linux/drivers/scsi/ufs/ufshcd-pci.c
Adrian Hunter c763729a10 scsi: ufs-pci: Fix restore from S4 for Intel controllers
Currently, ufshcd-pci is the only UFS driver with support for
suspend-to-disk PM callbacks (i.e. freeze/thaw/restore/poweroff). These
callbacks are set by the macro SET_SYSTEM_SLEEP_PM_OPS to the same
functions as system suspend/resume. That will work with spm_lvl 5 because
spm_lvl 5 will result in a full restore for the ->restore() callback.  In
the absence of a full restore, the host controller registers will have
values set up by the restore kernel (the kernel that boots and loads the
restore image) which are not necessarily the same. However it turns out,
the only registers that sometimes need restore are the base address
registers. This has gone un-noticed because, depending on IOMMU settings,
the kernel can end up allocating the same addresses every time.

For Intel controllers, an spm_lvl other than 5 can be used, so to support
S4 (suspend-to-disk) with spm_lvl other than 5, restore the base address
registers.

Link: https://lore.kernel.org/r/20201207083120.26732-2-adrian.hunter@intel.com
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-12-09 11:34:20 -05:00

360 lines
8.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Universal Flash Storage Host controller PCI glue driver
*
* This code is based on drivers/scsi/ufs/ufshcd-pci.c
* Copyright (C) 2011-2013 Samsung India Software Operations
*
* Authors:
* Santosh Yaraganavi <santosh.sy@samsung.com>
* Vinayak Holikatti <h.vinayak@samsung.com>
*/
#include "ufshcd.h"
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include <linux/pm_qos.h>
#include <linux/debugfs.h>
struct intel_host {
u32 active_ltr;
u32 idle_ltr;
struct dentry *debugfs_root;
};
static int ufs_intel_disable_lcc(struct ufs_hba *hba)
{
u32 attr = UIC_ARG_MIB(PA_LOCAL_TX_LCC_ENABLE);
u32 lcc_enable = 0;
ufshcd_dme_get(hba, attr, &lcc_enable);
if (lcc_enable)
ufshcd_disable_host_tx_lcc(hba);
return 0;
}
static int ufs_intel_link_startup_notify(struct ufs_hba *hba,
enum ufs_notify_change_status status)
{
int err = 0;
switch (status) {
case PRE_CHANGE:
err = ufs_intel_disable_lcc(hba);
break;
case POST_CHANGE:
break;
default:
break;
}
return err;
}
#define INTEL_ACTIVELTR 0x804
#define INTEL_IDLELTR 0x808
#define INTEL_LTR_REQ BIT(15)
#define INTEL_LTR_SCALE_MASK GENMASK(11, 10)
#define INTEL_LTR_SCALE_1US (2 << 10)
#define INTEL_LTR_SCALE_32US (3 << 10)
#define INTEL_LTR_VALUE_MASK GENMASK(9, 0)
static void intel_cache_ltr(struct ufs_hba *hba)
{
struct intel_host *host = ufshcd_get_variant(hba);
host->active_ltr = readl(hba->mmio_base + INTEL_ACTIVELTR);
host->idle_ltr = readl(hba->mmio_base + INTEL_IDLELTR);
}
static void intel_ltr_set(struct device *dev, s32 val)
{
struct ufs_hba *hba = dev_get_drvdata(dev);
struct intel_host *host = ufshcd_get_variant(hba);
u32 ltr;
pm_runtime_get_sync(dev);
/*
* Program latency tolerance (LTR) accordingly what has been asked
* by the PM QoS layer or disable it in case we were passed
* negative value or PM_QOS_LATENCY_ANY.
*/
ltr = readl(hba->mmio_base + INTEL_ACTIVELTR);
if (val == PM_QOS_LATENCY_ANY || val < 0) {
ltr &= ~INTEL_LTR_REQ;
} else {
ltr |= INTEL_LTR_REQ;
ltr &= ~INTEL_LTR_SCALE_MASK;
ltr &= ~INTEL_LTR_VALUE_MASK;
if (val > INTEL_LTR_VALUE_MASK) {
val >>= 5;
if (val > INTEL_LTR_VALUE_MASK)
val = INTEL_LTR_VALUE_MASK;
ltr |= INTEL_LTR_SCALE_32US | val;
} else {
ltr |= INTEL_LTR_SCALE_1US | val;
}
}
if (ltr == host->active_ltr)
goto out;
writel(ltr, hba->mmio_base + INTEL_ACTIVELTR);
writel(ltr, hba->mmio_base + INTEL_IDLELTR);
/* Cache the values into intel_host structure */
intel_cache_ltr(hba);
out:
pm_runtime_put(dev);
}
static void intel_ltr_expose(struct device *dev)
{
dev->power.set_latency_tolerance = intel_ltr_set;
dev_pm_qos_expose_latency_tolerance(dev);
}
static void intel_ltr_hide(struct device *dev)
{
dev_pm_qos_hide_latency_tolerance(dev);
dev->power.set_latency_tolerance = NULL;
}
static void intel_add_debugfs(struct ufs_hba *hba)
{
struct dentry *dir = debugfs_create_dir(dev_name(hba->dev), NULL);
struct intel_host *host = ufshcd_get_variant(hba);
intel_cache_ltr(hba);
host->debugfs_root = dir;
debugfs_create_x32("active_ltr", 0444, dir, &host->active_ltr);
debugfs_create_x32("idle_ltr", 0444, dir, &host->idle_ltr);
}
static void intel_remove_debugfs(struct ufs_hba *hba)
{
struct intel_host *host = ufshcd_get_variant(hba);
debugfs_remove_recursive(host->debugfs_root);
}
static int ufs_intel_common_init(struct ufs_hba *hba)
{
struct intel_host *host;
host = devm_kzalloc(hba->dev, sizeof(*host), GFP_KERNEL);
if (!host)
return -ENOMEM;
ufshcd_set_variant(hba, host);
intel_ltr_expose(hba->dev);
intel_add_debugfs(hba);
return 0;
}
static void ufs_intel_common_exit(struct ufs_hba *hba)
{
intel_remove_debugfs(hba);
intel_ltr_hide(hba->dev);
}
static int ufs_intel_resume(struct ufs_hba *hba, enum ufs_pm_op op)
{
/*
* To support S4 (suspend-to-disk) with spm_lvl other than 5, the base
* address registers must be restored because the restore kernel can
* have used different addresses.
*/
ufshcd_writel(hba, lower_32_bits(hba->utrdl_dma_addr),
REG_UTP_TRANSFER_REQ_LIST_BASE_L);
ufshcd_writel(hba, upper_32_bits(hba->utrdl_dma_addr),
REG_UTP_TRANSFER_REQ_LIST_BASE_H);
ufshcd_writel(hba, lower_32_bits(hba->utmrdl_dma_addr),
REG_UTP_TASK_REQ_LIST_BASE_L);
ufshcd_writel(hba, upper_32_bits(hba->utmrdl_dma_addr),
REG_UTP_TASK_REQ_LIST_BASE_H);
return 0;
}
static int ufs_intel_ehl_init(struct ufs_hba *hba)
{
hba->quirks |= UFSHCD_QUIRK_BROKEN_AUTO_HIBERN8;
return ufs_intel_common_init(hba);
}
static struct ufs_hba_variant_ops ufs_intel_cnl_hba_vops = {
.name = "intel-pci",
.init = ufs_intel_common_init,
.exit = ufs_intel_common_exit,
.link_startup_notify = ufs_intel_link_startup_notify,
.resume = ufs_intel_resume,
};
static struct ufs_hba_variant_ops ufs_intel_ehl_hba_vops = {
.name = "intel-pci",
.init = ufs_intel_ehl_init,
.exit = ufs_intel_common_exit,
.link_startup_notify = ufs_intel_link_startup_notify,
.resume = ufs_intel_resume,
};
#ifdef CONFIG_PM_SLEEP
/**
* ufshcd_pci_suspend - suspend power management function
* @dev: pointer to PCI device handle
*
* Returns 0 if successful
* Returns non-zero otherwise
*/
static int ufshcd_pci_suspend(struct device *dev)
{
return ufshcd_system_suspend(dev_get_drvdata(dev));
}
/**
* ufshcd_pci_resume - resume power management function
* @dev: pointer to PCI device handle
*
* Returns 0 if successful
* Returns non-zero otherwise
*/
static int ufshcd_pci_resume(struct device *dev)
{
return ufshcd_system_resume(dev_get_drvdata(dev));
}
#endif /* !CONFIG_PM_SLEEP */
#ifdef CONFIG_PM
static int ufshcd_pci_runtime_suspend(struct device *dev)
{
return ufshcd_runtime_suspend(dev_get_drvdata(dev));
}
static int ufshcd_pci_runtime_resume(struct device *dev)
{
return ufshcd_runtime_resume(dev_get_drvdata(dev));
}
static int ufshcd_pci_runtime_idle(struct device *dev)
{
return ufshcd_runtime_idle(dev_get_drvdata(dev));
}
#endif /* !CONFIG_PM */
/**
* ufshcd_pci_shutdown - main function to put the controller in reset state
* @pdev: pointer to PCI device handle
*/
static void ufshcd_pci_shutdown(struct pci_dev *pdev)
{
ufshcd_shutdown((struct ufs_hba *)pci_get_drvdata(pdev));
}
/**
* ufshcd_pci_remove - de-allocate PCI/SCSI host and host memory space
* data structure memory
* @pdev: pointer to PCI handle
*/
static void ufshcd_pci_remove(struct pci_dev *pdev)
{
struct ufs_hba *hba = pci_get_drvdata(pdev);
pm_runtime_forbid(&pdev->dev);
pm_runtime_get_noresume(&pdev->dev);
ufshcd_remove(hba);
ufshcd_dealloc_host(hba);
}
/**
* ufshcd_pci_probe - probe routine of the driver
* @pdev: pointer to PCI device handle
* @id: PCI device id
*
* Returns 0 on success, non-zero value on failure
*/
static int
ufshcd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct ufs_hba *hba;
void __iomem *mmio_base;
int err;
err = pcim_enable_device(pdev);
if (err) {
dev_err(&pdev->dev, "pcim_enable_device failed\n");
return err;
}
pci_set_master(pdev);
err = pcim_iomap_regions(pdev, 1 << 0, UFSHCD);
if (err < 0) {
dev_err(&pdev->dev, "request and iomap failed\n");
return err;
}
mmio_base = pcim_iomap_table(pdev)[0];
err = ufshcd_alloc_host(&pdev->dev, &hba);
if (err) {
dev_err(&pdev->dev, "Allocation failed\n");
return err;
}
pci_set_drvdata(pdev, hba);
hba->vops = (struct ufs_hba_variant_ops *)id->driver_data;
err = ufshcd_init(hba, mmio_base, pdev->irq);
if (err) {
dev_err(&pdev->dev, "Initialization failed\n");
ufshcd_dealloc_host(hba);
return err;
}
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_allow(&pdev->dev);
return 0;
}
static const struct dev_pm_ops ufshcd_pci_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(ufshcd_pci_suspend,
ufshcd_pci_resume)
SET_RUNTIME_PM_OPS(ufshcd_pci_runtime_suspend,
ufshcd_pci_runtime_resume,
ufshcd_pci_runtime_idle)
};
static const struct pci_device_id ufshcd_pci_tbl[] = {
{ PCI_VENDOR_ID_SAMSUNG, 0xC00C, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
{ PCI_VDEVICE(INTEL, 0x9DFA), (kernel_ulong_t)&ufs_intel_cnl_hba_vops },
{ PCI_VDEVICE(INTEL, 0x4B41), (kernel_ulong_t)&ufs_intel_ehl_hba_vops },
{ PCI_VDEVICE(INTEL, 0x4B43), (kernel_ulong_t)&ufs_intel_ehl_hba_vops },
{ } /* terminate list */
};
MODULE_DEVICE_TABLE(pci, ufshcd_pci_tbl);
static struct pci_driver ufshcd_pci_driver = {
.name = UFSHCD,
.id_table = ufshcd_pci_tbl,
.probe = ufshcd_pci_probe,
.remove = ufshcd_pci_remove,
.shutdown = ufshcd_pci_shutdown,
.driver = {
.pm = &ufshcd_pci_pm_ops
},
};
module_pci_driver(ufshcd_pci_driver);
MODULE_AUTHOR("Santosh Yaragnavi <santosh.sy@samsung.com>");
MODULE_AUTHOR("Vinayak Holikatti <h.vinayak@samsung.com>");
MODULE_DESCRIPTION("UFS host controller PCI glue driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(UFSHCD_DRIVER_VERSION);