linux/drivers/cxl/pci.c

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// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2020 Intel Corporation. All rights reserved. */
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/moduleparam.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/sizes.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/io.h>
#include "cxlmem.h"
#include "pci.h"
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
#include "cxl.h"
/**
cxl: Rename mem to pci As the driver has undergone development, it's become clear that the majority [entirety?] of the current functionality in mem.c is actually a layer encapsulating functionality exposed through PCI based interactions. This layer can be used either in isolation or to provide functionality for higher level functionality. CXL capabilities exist in a parallel domain to PCIe. CXL devices are enumerable and controllable via "legacy" PCIe mechanisms; however, their CXL capabilities are a superset of PCIe. For example, a CXL device may be connected to a non-CXL capable PCIe root port, and therefore will not be able to participate in CXL.mem or CXL.cache operations, but can still be accessed through PCIe mechanisms for CXL.io operations. To properly represent the PCI nature of this driver, and in preparation for introducing a new driver for the CXL.mem / HDM decoder (Host-managed Device Memory) capabilities of a CXL memory expander, rename mem.c to pci.c so that mem.c is available for this new driver. The result of the change is that there is a clear layering distinction in the driver, and a systems administrator may load only the cxl_pci module and gain access to such operations as, firmware update, offline provisioning of devices, and error collection. In addition to freeing up the file name for another purpose, there are two primary reasons this is useful, 1. Acting upon devices which don't have full CXL capabilities. This may happen for instance if the CXL device is connected in a CXL unaware part of the platform topology. 2. Userspace-first provisioning for devices without kernel driver interference. This may be useful when provisioning a new device in a specific manner that might otherwise be blocked or prevented by the real CXL mem driver. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Link: https://lore.kernel.org/r/20210526174413.802913-1-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-05-26 17:44:13 +00:00
* DOC: cxl pci
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
*
cxl: Rename mem to pci As the driver has undergone development, it's become clear that the majority [entirety?] of the current functionality in mem.c is actually a layer encapsulating functionality exposed through PCI based interactions. This layer can be used either in isolation or to provide functionality for higher level functionality. CXL capabilities exist in a parallel domain to PCIe. CXL devices are enumerable and controllable via "legacy" PCIe mechanisms; however, their CXL capabilities are a superset of PCIe. For example, a CXL device may be connected to a non-CXL capable PCIe root port, and therefore will not be able to participate in CXL.mem or CXL.cache operations, but can still be accessed through PCIe mechanisms for CXL.io operations. To properly represent the PCI nature of this driver, and in preparation for introducing a new driver for the CXL.mem / HDM decoder (Host-managed Device Memory) capabilities of a CXL memory expander, rename mem.c to pci.c so that mem.c is available for this new driver. The result of the change is that there is a clear layering distinction in the driver, and a systems administrator may load only the cxl_pci module and gain access to such operations as, firmware update, offline provisioning of devices, and error collection. In addition to freeing up the file name for another purpose, there are two primary reasons this is useful, 1. Acting upon devices which don't have full CXL capabilities. This may happen for instance if the CXL device is connected in a CXL unaware part of the platform topology. 2. Userspace-first provisioning for devices without kernel driver interference. This may be useful when provisioning a new device in a specific manner that might otherwise be blocked or prevented by the real CXL mem driver. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Link: https://lore.kernel.org/r/20210526174413.802913-1-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-05-26 17:44:13 +00:00
* This implements the PCI exclusive functionality for a CXL device as it is
* defined by the Compute Express Link specification. CXL devices may surface
* certain functionality even if it isn't CXL enabled. While this driver is
* focused around the PCI specific aspects of a CXL device, it binds to the
* specific CXL memory device class code, and therefore the implementation of
* cxl_pci is focused around CXL memory devices.
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
*
* The driver has several responsibilities, mainly:
* - Create the memX device and register on the CXL bus.
* - Enumerate device's register interface and map them.
* - Registers nvdimm bridge device with cxl_core.
* - Registers a CXL mailbox with cxl_core.
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
*/
#define cxl_doorbell_busy(cxlds) \
(readl((cxlds)->regs.mbox + CXLDEV_MBOX_CTRL_OFFSET) & \
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
CXLDEV_MBOX_CTRL_DOORBELL)
/* CXL 2.0 - 8.2.8.4 */
#define CXL_MAILBOX_TIMEOUT_MS (2 * HZ)
/*
* CXL 2.0 ECN "Add Mailbox Ready Time" defines a capability field to
* dictate how long to wait for the mailbox to become ready. The new
* field allows the device to tell software the amount of time to wait
* before mailbox ready. This field per the spec theoretically allows
* for up to 255 seconds. 255 seconds is unreasonably long, its longer
* than the maximum SATA port link recovery wait. Default to 60 seconds
* until someone builds a CXL device that needs more time in practice.
*/
static unsigned short mbox_ready_timeout = 60;
module_param(mbox_ready_timeout, ushort, 0644);
MODULE_PARM_DESC(mbox_ready_timeout,
"seconds to wait for mailbox ready status");
static int cxl_pci_mbox_wait_for_doorbell(struct cxl_dev_state *cxlds)
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
{
const unsigned long start = jiffies;
unsigned long end = start;
while (cxl_doorbell_busy(cxlds)) {
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
end = jiffies;
if (time_after(end, start + CXL_MAILBOX_TIMEOUT_MS)) {
/* Check again in case preempted before timeout test */
if (!cxl_doorbell_busy(cxlds))
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
break;
return -ETIMEDOUT;
}
cpu_relax();
}
dev_dbg(cxlds->dev, "Doorbell wait took %dms",
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
jiffies_to_msecs(end) - jiffies_to_msecs(start));
return 0;
}
static void cxl_pci_mbox_timeout(struct cxl_dev_state *cxlds,
struct cxl_mbox_cmd *mbox_cmd)
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
{
struct device *dev = cxlds->dev;
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
dev_dbg(dev, "Mailbox command (opcode: %#x size: %zub) timed out\n",
mbox_cmd->opcode, mbox_cmd->size_in);
}
/**
* __cxl_pci_mbox_send_cmd() - Execute a mailbox command
* @cxlds: The device state to communicate with.
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
* @mbox_cmd: Command to send to the memory device.
*
* Context: Any context. Expects mbox_mutex to be held.
* Return: -ETIMEDOUT if timeout occurred waiting for completion. 0 on success.
* Caller should check the return code in @mbox_cmd to make sure it
* succeeded.
*
* This is a generic form of the CXL mailbox send command thus only using the
* registers defined by the mailbox capability ID - CXL 2.0 8.2.8.4. Memory
* devices, and perhaps other types of CXL devices may have further information
* available upon error conditions. Driver facilities wishing to send mailbox
* commands should use the wrapper command.
*
* The CXL spec allows for up to two mailboxes. The intention is for the primary
* mailbox to be OS controlled and the secondary mailbox to be used by system
* firmware. This allows the OS and firmware to communicate with the device and
* not need to coordinate with each other. The driver only uses the primary
* mailbox.
*/
static int __cxl_pci_mbox_send_cmd(struct cxl_dev_state *cxlds,
struct cxl_mbox_cmd *mbox_cmd)
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
{
void __iomem *payload = cxlds->regs.mbox + CXLDEV_MBOX_PAYLOAD_OFFSET;
struct device *dev = cxlds->dev;
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
u64 cmd_reg, status_reg;
size_t out_len;
int rc;
lockdep_assert_held(&cxlds->mbox_mutex);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
/*
* Here are the steps from 8.2.8.4 of the CXL 2.0 spec.
* 1. Caller reads MB Control Register to verify doorbell is clear
* 2. Caller writes Command Register
* 3. Caller writes Command Payload Registers if input payload is non-empty
* 4. Caller writes MB Control Register to set doorbell
* 5. Caller either polls for doorbell to be clear or waits for interrupt if configured
* 6. Caller reads MB Status Register to fetch Return code
* 7. If command successful, Caller reads Command Register to get Payload Length
* 8. If output payload is non-empty, host reads Command Payload Registers
*
* Hardware is free to do whatever it wants before the doorbell is rung,
* and isn't allowed to change anything after it clears the doorbell. As
* such, steps 2 and 3 can happen in any order, and steps 6, 7, 8 can
* also happen in any order (though some orders might not make sense).
*/
/* #1 */
if (cxl_doorbell_busy(cxlds)) {
dev_err_ratelimited(dev, "Mailbox re-busy after acquiring\n");
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
return -EBUSY;
}
cmd_reg = FIELD_PREP(CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK,
mbox_cmd->opcode);
if (mbox_cmd->size_in) {
if (WARN_ON(!mbox_cmd->payload_in))
return -EINVAL;
cmd_reg |= FIELD_PREP(CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK,
mbox_cmd->size_in);
memcpy_toio(payload, mbox_cmd->payload_in, mbox_cmd->size_in);
}
/* #2, #3 */
writeq(cmd_reg, cxlds->regs.mbox + CXLDEV_MBOX_CMD_OFFSET);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
/* #4 */
dev_dbg(dev, "Sending command\n");
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
writel(CXLDEV_MBOX_CTRL_DOORBELL,
cxlds->regs.mbox + CXLDEV_MBOX_CTRL_OFFSET);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
/* #5 */
rc = cxl_pci_mbox_wait_for_doorbell(cxlds);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
if (rc == -ETIMEDOUT) {
cxl_pci_mbox_timeout(cxlds, mbox_cmd);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
return rc;
}
/* #6 */
status_reg = readq(cxlds->regs.mbox + CXLDEV_MBOX_STATUS_OFFSET);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
mbox_cmd->return_code =
FIELD_GET(CXLDEV_MBOX_STATUS_RET_CODE_MASK, status_reg);
if (mbox_cmd->return_code != 0) {
dev_dbg(dev, "Mailbox operation had an error\n");
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
return 0;
}
/* #7 */
cmd_reg = readq(cxlds->regs.mbox + CXLDEV_MBOX_CMD_OFFSET);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
out_len = FIELD_GET(CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK, cmd_reg);
/* #8 */
if (out_len && mbox_cmd->payload_out) {
/*
* Sanitize the copy. If hardware misbehaves, out_len per the
* spec can actually be greater than the max allowed size (21
* bits available but spec defined 1M max). The caller also may
* have requested less data than the hardware supplied even
* within spec.
*/
size_t n = min3(mbox_cmd->size_out, cxlds->payload_size, out_len);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
memcpy_fromio(mbox_cmd->payload_out, payload, n);
mbox_cmd->size_out = n;
} else {
mbox_cmd->size_out = 0;
}
return 0;
}
/**
* cxl_pci_mbox_get() - Acquire exclusive access to the mailbox.
* @cxlds: The device state to gain access to.
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
*
* Context: Any context. Takes the mbox_mutex.
* Return: 0 if exclusive access was acquired.
*/
static int cxl_pci_mbox_get(struct cxl_dev_state *cxlds)
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
{
struct device *dev = cxlds->dev;
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
u64 md_status;
int rc;
mutex_lock_io(&cxlds->mbox_mutex);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
/*
* XXX: There is some amount of ambiguity in the 2.0 version of the spec
* around the mailbox interface ready (8.2.8.5.1.1). The purpose of the
* bit is to allow firmware running on the device to notify the driver
* that it's ready to receive commands. It is unclear if the bit needs
* to be read for each transaction mailbox, ie. the firmware can switch
* it on and off as needed. Second, there is no defined timeout for
* mailbox ready, like there is for the doorbell interface.
*
* Assumptions:
* 1. The firmware might toggle the Mailbox Interface Ready bit, check
* it for every command.
*
* 2. If the doorbell is clear, the firmware should have first set the
* Mailbox Interface Ready bit. Therefore, waiting for the doorbell
* to be ready is sufficient.
*/
rc = cxl_pci_mbox_wait_for_doorbell(cxlds);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
if (rc) {
dev_warn(dev, "Mailbox interface not ready\n");
goto out;
}
md_status = readq(cxlds->regs.memdev + CXLMDEV_STATUS_OFFSET);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
if (!(md_status & CXLMDEV_MBOX_IF_READY && CXLMDEV_READY(md_status))) {
dev_err(dev, "mbox: reported doorbell ready, but not mbox ready\n");
rc = -EBUSY;
goto out;
}
/*
* Hardware shouldn't allow a ready status but also have failure bits
* set. Spit out an error, this should be a bug report
*/
rc = -EFAULT;
if (md_status & CXLMDEV_DEV_FATAL) {
dev_err(dev, "mbox: reported ready, but fatal\n");
goto out;
}
if (md_status & CXLMDEV_FW_HALT) {
dev_err(dev, "mbox: reported ready, but halted\n");
goto out;
}
if (CXLMDEV_RESET_NEEDED(md_status)) {
dev_err(dev, "mbox: reported ready, but reset needed\n");
goto out;
}
/* with lock held */
return 0;
out:
mutex_unlock(&cxlds->mbox_mutex);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
return rc;
}
/**
* cxl_pci_mbox_put() - Release exclusive access to the mailbox.
* @cxlds: The device state to communicate with.
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
*
* Context: Any context. Expects mbox_mutex to be held.
*/
static void cxl_pci_mbox_put(struct cxl_dev_state *cxlds)
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
{
mutex_unlock(&cxlds->mbox_mutex);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
}
static int cxl_pci_mbox_send(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
{
int rc;
rc = cxl_pci_mbox_get(cxlds);
if (rc)
return rc;
rc = __cxl_pci_mbox_send_cmd(cxlds, cmd);
cxl_pci_mbox_put(cxlds);
return rc;
}
static int cxl_pci_setup_mailbox(struct cxl_dev_state *cxlds)
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
{
const int cap = readl(cxlds->regs.mbox + CXLDEV_MBOX_CAPS_OFFSET);
unsigned long timeout;
u64 md_status;
timeout = jiffies + mbox_ready_timeout * HZ;
do {
md_status = readq(cxlds->regs.memdev + CXLMDEV_STATUS_OFFSET);
if (md_status & CXLMDEV_MBOX_IF_READY)
break;
if (msleep_interruptible(100))
break;
} while (!time_after(jiffies, timeout));
if (!(md_status & CXLMDEV_MBOX_IF_READY)) {
dev_err(cxlds->dev,
"timeout awaiting mailbox ready, device state:%s%s\n",
md_status & CXLMDEV_DEV_FATAL ? " fatal" : "",
md_status & CXLMDEV_FW_HALT ? " firmware-halt" : "");
return -EIO;
}
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
cxlds->mbox_send = cxl_pci_mbox_send;
cxlds->payload_size =
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
1 << FIELD_GET(CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK, cap);
/*
* CXL 2.0 8.2.8.4.3 Mailbox Capabilities Register
*
* If the size is too small, mandatory commands will not work and so
* there's no point in going forward. If the size is too large, there's
* no harm is soft limiting it.
*/
cxlds->payload_size = min_t(size_t, cxlds->payload_size, SZ_1M);
if (cxlds->payload_size < 256) {
dev_err(cxlds->dev, "Mailbox is too small (%zub)",
cxlds->payload_size);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
return -ENXIO;
}
dev_dbg(cxlds->dev, "Mailbox payload sized %zu",
cxlds->payload_size);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
return 0;
}
static int cxl_map_regblock(struct pci_dev *pdev, struct cxl_register_map *map)
{
void __iomem *addr;
int bar = map->barno;
struct device *dev = &pdev->dev;
resource_size_t offset = map->block_offset;
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
/* Basic sanity check that BAR is big enough */
if (pci_resource_len(pdev, bar) < offset) {
dev_err(dev, "BAR%d: %pr: too small (offset: %pa)\n", bar,
&pdev->resource[bar], &offset);
return -ENXIO;
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
}
addr = pci_iomap(pdev, bar, 0);
if (!addr) {
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
dev_err(dev, "failed to map registers\n");
return -ENOMEM;
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
}
dev_dbg(dev, "Mapped CXL Memory Device resource bar %u @ %pa\n",
bar, &offset);
map->base = addr + map->block_offset;
return 0;
}
static void cxl_unmap_regblock(struct pci_dev *pdev,
struct cxl_register_map *map)
{
pci_iounmap(pdev, map->base - map->block_offset);
map->base = NULL;
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
}
static int cxl_probe_regs(struct pci_dev *pdev, struct cxl_register_map *map)
{
struct cxl_component_reg_map *comp_map;
struct cxl_device_reg_map *dev_map;
struct device *dev = &pdev->dev;
void __iomem *base = map->base;
switch (map->reg_type) {
case CXL_REGLOC_RBI_COMPONENT:
comp_map = &map->component_map;
cxl_probe_component_regs(dev, base, comp_map);
if (!comp_map->hdm_decoder.valid) {
dev_err(dev, "HDM decoder registers not found\n");
return -ENXIO;
}
dev_dbg(dev, "Set up component registers\n");
break;
case CXL_REGLOC_RBI_MEMDEV:
dev_map = &map->device_map;
cxl_probe_device_regs(dev, base, dev_map);
if (!dev_map->status.valid || !dev_map->mbox.valid ||
!dev_map->memdev.valid) {
dev_err(dev, "registers not found: %s%s%s\n",
!dev_map->status.valid ? "status " : "",
!dev_map->mbox.valid ? "mbox " : "",
!dev_map->memdev.valid ? "memdev " : "");
return -ENXIO;
}
dev_dbg(dev, "Probing device registers...\n");
break;
default:
break;
}
return 0;
}
static int cxl_map_regs(struct cxl_dev_state *cxlds, struct cxl_register_map *map)
{
struct device *dev = cxlds->dev;
struct pci_dev *pdev = to_pci_dev(dev);
switch (map->reg_type) {
case CXL_REGLOC_RBI_COMPONENT:
cxl_map_component_regs(pdev, &cxlds->regs.component, map);
dev_dbg(dev, "Mapping component registers...\n");
break;
case CXL_REGLOC_RBI_MEMDEV:
cxl_map_device_regs(pdev, &cxlds->regs.device_regs, map);
dev_dbg(dev, "Probing device registers...\n");
break;
default:
break;
}
return 0;
}
static void cxl_decode_regblock(u32 reg_lo, u32 reg_hi,
struct cxl_register_map *map)
{
map->block_offset =
((u64)reg_hi << 32) | (reg_lo & CXL_REGLOC_ADDR_MASK);
map->barno = FIELD_GET(CXL_REGLOC_BIR_MASK, reg_lo);
map->reg_type = FIELD_GET(CXL_REGLOC_RBI_MASK, reg_lo);
}
/**
* cxl_find_regblock() - Locate register blocks by type
* @pdev: The CXL PCI device to enumerate.
* @type: Register Block Indicator id
* @map: Enumeration output, clobbered on error
*
* Return: 0 if register block enumerated, negative error code otherwise
*
* A CXL DVSEC may point to one or more register blocks, search for them
* by @type.
*/
static int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
struct cxl_register_map *map)
{
u32 regloc_size, regblocks;
int regloc, i;
regloc = pci_find_dvsec_capability(pdev, PCI_DVSEC_VENDOR_ID_CXL,
PCI_DVSEC_ID_CXL_REGLOC_DVSEC_ID);
if (!regloc)
return -ENXIO;
pci_read_config_dword(pdev, regloc + PCI_DVSEC_HEADER1, &regloc_size);
regloc_size = FIELD_GET(PCI_DVSEC_HEADER1_LENGTH_MASK, regloc_size);
regloc += PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET;
regblocks = (regloc_size - PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET) / 8;
for (i = 0; i < regblocks; i++, regloc += 8) {
u32 reg_lo, reg_hi;
pci_read_config_dword(pdev, regloc, &reg_lo);
pci_read_config_dword(pdev, regloc + 4, &reg_hi);
cxl_decode_regblock(reg_lo, reg_hi, map);
if (map->reg_type == type)
return 0;
}
return -ENODEV;
}
static int cxl_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
struct cxl_register_map *map)
{
int rc;
rc = cxl_find_regblock(pdev, type, map);
if (rc)
return rc;
rc = cxl_map_regblock(pdev, map);
if (rc)
return rc;
rc = cxl_probe_regs(pdev, map);
cxl_unmap_regblock(pdev, map);
return rc;
}
static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct cxl_register_map map;
struct cxl_memdev *cxlmd;
struct cxl_dev_state *cxlds;
int rc;
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
/*
* Double check the anonymous union trickery in struct cxl_regs
* FIXME switch to struct_group()
*/
BUILD_BUG_ON(offsetof(struct cxl_regs, memdev) !=
offsetof(struct cxl_regs, device_regs.memdev));
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
rc = pcim_enable_device(pdev);
if (rc)
return rc;
cxlds = cxl_dev_state_create(&pdev->dev);
if (IS_ERR(cxlds))
return PTR_ERR(cxlds);
rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map);
if (rc)
return rc;
rc = cxl_map_regs(cxlds, &map);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
if (rc)
return rc;
rc = cxl_pci_setup_mailbox(cxlds);
cxl/mem: Find device capabilities Provide enough functionality to utilize the mailbox of a memory device. The mailbox is used to interact with the firmware running on the memory device. The flow is proven with one implemented command, "identify". Because the class code has already told the driver this is a memory device and the identify command is mandatory. CXL devices contain an array of capabilities that describe the interactions software can have with the device or firmware running on the device. A CXL compliant device must implement the device status and the mailbox capability. Additionally, a CXL compliant memory device must implement the memory device capability. Each of the capabilities can [will] provide an offset within the MMIO region for interacting with the CXL device. The capabilities tell the driver how to find and map the register space for CXL Memory Devices. The registers are required to utilize the CXL spec defined mailbox interface. The spec outlines two mailboxes, primary and secondary. The secondary mailbox is earmarked for system firmware, and not handled in this driver. Primary mailboxes are capable of generating an interrupt when submitting a background command. That implementation is saved for a later time. Reported-by: Colin Ian King <colin.king@canonical.com> (coverity) Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Link: https://www.computeexpresslink.org/download-the-specification Link: https://lore.kernel.org/r/20210217040958.1354670-3-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:51 +00:00
if (rc)
return rc;
rc = cxl_enumerate_cmds(cxlds);
cxl/mem: Enable commands via CEL CXL devices identified by the memory-device class code must implement the Device Command Interface (described in 8.2.9 of the CXL 2.0 spec). While the driver already maintains a list of commands it supports, there is still a need to be able to distinguish between commands that the driver knows about from commands that are optionally supported by the hardware. The Command Effects Log (CEL) is specified in the CXL 2.0 specification. The CEL is one of two types of logs, the other being vendor specific. They are distinguished in hardware/spec via UUID. The CEL is useful for 2 things: 1. Determine which optional commands are supported by the CXL device. 2. Enumerate any vendor specific commands The CEL is used by the driver to determine which commands are available in the hardware and therefore which commands userspace is allowed to execute. The set of enabled commands might be a subset of commands which are advertised in UAPI via CXL_MEM_SEND_COMMAND IOCTL. With the CEL enabling comes a internal flag to indicate a base set of commands that are enabled regardless of CEL. Such commands are required for basic interaction with the hardware and thus can be useful in debug cases, for example if the CEL is corrupted. The implementation leaves the statically defined table of commands and supplements it with a bitmap to determine commands that are enabled. This organization was chosen for the following reasons: - Smaller memory footprint. Doesn't need a table per device. - Reduce memory allocation complexity. - Fixed command IDs to opcode mapping for all devices makes development and debugging easier. - Certain helpers are easily achievable, like cxl_for_each_cmd(). Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2) Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> (v3) Link: https://lore.kernel.org/r/20210217040958.1354670-7-ben.widawsky@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-02-17 04:09:55 +00:00
if (rc)
return rc;
rc = cxl_dev_state_identify(cxlds);
if (rc)
return rc;
rc = cxl_mem_create_range_info(cxlds);
if (rc)
return rc;
cxlmd = devm_cxl_add_memdev(cxlds);
if (IS_ERR(cxlmd))
return PTR_ERR(cxlmd);
if (range_len(&cxlds->pmem_range) && IS_ENABLED(CONFIG_CXL_PMEM))
rc = devm_cxl_add_nvdimm(&pdev->dev, cxlmd);
return rc;
}
static const struct pci_device_id cxl_mem_pci_tbl[] = {
/* PCI class code for CXL.mem Type-3 Devices */
{ PCI_DEVICE_CLASS((PCI_CLASS_MEMORY_CXL << 8 | CXL_MEMORY_PROGIF), ~0)},
{ /* terminate list */ },
};
MODULE_DEVICE_TABLE(pci, cxl_mem_pci_tbl);
static struct pci_driver cxl_pci_driver = {
.name = KBUILD_MODNAME,
.id_table = cxl_mem_pci_tbl,
.probe = cxl_pci_probe,
.driver = {
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
};
MODULE_LICENSE("GPL v2");
module_pci_driver(cxl_pci_driver);
MODULE_IMPORT_NS(CXL);