linux/drivers/pci/host/pci-host-common.c

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/*
* Generic PCI host driver common code
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright (C) 2014 ARM Limited
*
* Author: Will Deacon <will.deacon@arm.com>
*/
#include <linux/kernel.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/pci-ecam.h>
#include <linux/platform_device.h>
static int gen_pci_parse_request_of_pci_ranges(struct device *dev,
struct list_head *resources, struct resource **bus_range)
{
int err, res_valid = 0;
struct device_node *np = dev->of_node;
resource_size_t iobase;
PCI: generic: Fix pci_remap_iospace() failure path On ARM/ARM64 architectures, PCI IO ports are emulated through memory mapped IO, by reserving a chunk of virtual address space starting at PCI_IOBASE and by mapping the PCI host bridges memory address space driving PCI IO cycles to it. PCI host bridge drivers that enable downstream PCI IO cycles map the host bridge memory address responding to PCI IO cycles to the fixed virtual address space through the pci_remap_iospace() API. This means that if the pci_remap_iospace() function fails, the corresponding host bridge PCI IO resource must be considered invalid, in that there is no way for the kernel to actually drive PCI IO transactions if the memory addresses responding to PCI IO cycles cannot be mapped into the CPU virtual address space. The PCI common host bridge driver does not remove the PCI IO resource from the host bridge resource windows if the pci_remap_iospace() call fails; this is an actual bug in that the PCI host bridge would consider the PCI IO resource valid (and possibly assign it to downstream devices) even if the kernel was not able to map the PCI host bridge memory address driving IO cycle to the CPU virtual address space (ie pci_remap_iospace() failures). Fix the PCI host bridge driver pci_remap_iospace() failure path, by destroying the PCI host bridge PCI IO resources retrieved through firmware when the pci_remap_iospace() function call fails, therefore preventing the kernel from adding the respective PCI IO resource to the list of PCI host bridge valid resources, fixing the issue. Fixes: 4e64dbe226e7 ("PCI: generic: Expose pci_host_common_probe() for use by other drivers") Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Will Deacon <will.deacon@arm.com>
2016-08-15 16:50:45 +00:00
struct resource_entry *win, *tmp;
err = of_pci_get_host_bridge_resources(np, 0, 0xff, resources, &iobase);
if (err)
return err;
err = devm_request_pci_bus_resources(dev, resources);
if (err)
return err;
PCI: generic: Fix pci_remap_iospace() failure path On ARM/ARM64 architectures, PCI IO ports are emulated through memory mapped IO, by reserving a chunk of virtual address space starting at PCI_IOBASE and by mapping the PCI host bridges memory address space driving PCI IO cycles to it. PCI host bridge drivers that enable downstream PCI IO cycles map the host bridge memory address responding to PCI IO cycles to the fixed virtual address space through the pci_remap_iospace() API. This means that if the pci_remap_iospace() function fails, the corresponding host bridge PCI IO resource must be considered invalid, in that there is no way for the kernel to actually drive PCI IO transactions if the memory addresses responding to PCI IO cycles cannot be mapped into the CPU virtual address space. The PCI common host bridge driver does not remove the PCI IO resource from the host bridge resource windows if the pci_remap_iospace() call fails; this is an actual bug in that the PCI host bridge would consider the PCI IO resource valid (and possibly assign it to downstream devices) even if the kernel was not able to map the PCI host bridge memory address driving IO cycle to the CPU virtual address space (ie pci_remap_iospace() failures). Fix the PCI host bridge driver pci_remap_iospace() failure path, by destroying the PCI host bridge PCI IO resources retrieved through firmware when the pci_remap_iospace() function call fails, therefore preventing the kernel from adding the respective PCI IO resource to the list of PCI host bridge valid resources, fixing the issue. Fixes: 4e64dbe226e7 ("PCI: generic: Expose pci_host_common_probe() for use by other drivers") Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Will Deacon <will.deacon@arm.com>
2016-08-15 16:50:45 +00:00
resource_list_for_each_entry_safe(win, tmp, resources) {
struct resource *res = win->res;
switch (resource_type(res)) {
case IORESOURCE_IO:
err = pci_remap_iospace(res, iobase);
PCI: generic: Fix pci_remap_iospace() failure path On ARM/ARM64 architectures, PCI IO ports are emulated through memory mapped IO, by reserving a chunk of virtual address space starting at PCI_IOBASE and by mapping the PCI host bridges memory address space driving PCI IO cycles to it. PCI host bridge drivers that enable downstream PCI IO cycles map the host bridge memory address responding to PCI IO cycles to the fixed virtual address space through the pci_remap_iospace() API. This means that if the pci_remap_iospace() function fails, the corresponding host bridge PCI IO resource must be considered invalid, in that there is no way for the kernel to actually drive PCI IO transactions if the memory addresses responding to PCI IO cycles cannot be mapped into the CPU virtual address space. The PCI common host bridge driver does not remove the PCI IO resource from the host bridge resource windows if the pci_remap_iospace() call fails; this is an actual bug in that the PCI host bridge would consider the PCI IO resource valid (and possibly assign it to downstream devices) even if the kernel was not able to map the PCI host bridge memory address driving IO cycle to the CPU virtual address space (ie pci_remap_iospace() failures). Fix the PCI host bridge driver pci_remap_iospace() failure path, by destroying the PCI host bridge PCI IO resources retrieved through firmware when the pci_remap_iospace() function call fails, therefore preventing the kernel from adding the respective PCI IO resource to the list of PCI host bridge valid resources, fixing the issue. Fixes: 4e64dbe226e7 ("PCI: generic: Expose pci_host_common_probe() for use by other drivers") Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Will Deacon <will.deacon@arm.com>
2016-08-15 16:50:45 +00:00
if (err) {
dev_warn(dev, "error %d: failed to map resource %pR\n",
err, res);
PCI: generic: Fix pci_remap_iospace() failure path On ARM/ARM64 architectures, PCI IO ports are emulated through memory mapped IO, by reserving a chunk of virtual address space starting at PCI_IOBASE and by mapping the PCI host bridges memory address space driving PCI IO cycles to it. PCI host bridge drivers that enable downstream PCI IO cycles map the host bridge memory address responding to PCI IO cycles to the fixed virtual address space through the pci_remap_iospace() API. This means that if the pci_remap_iospace() function fails, the corresponding host bridge PCI IO resource must be considered invalid, in that there is no way for the kernel to actually drive PCI IO transactions if the memory addresses responding to PCI IO cycles cannot be mapped into the CPU virtual address space. The PCI common host bridge driver does not remove the PCI IO resource from the host bridge resource windows if the pci_remap_iospace() call fails; this is an actual bug in that the PCI host bridge would consider the PCI IO resource valid (and possibly assign it to downstream devices) even if the kernel was not able to map the PCI host bridge memory address driving IO cycle to the CPU virtual address space (ie pci_remap_iospace() failures). Fix the PCI host bridge driver pci_remap_iospace() failure path, by destroying the PCI host bridge PCI IO resources retrieved through firmware when the pci_remap_iospace() function call fails, therefore preventing the kernel from adding the respective PCI IO resource to the list of PCI host bridge valid resources, fixing the issue. Fixes: 4e64dbe226e7 ("PCI: generic: Expose pci_host_common_probe() for use by other drivers") Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Will Deacon <will.deacon@arm.com>
2016-08-15 16:50:45 +00:00
resource_list_destroy_entry(win);
}
break;
case IORESOURCE_MEM:
res_valid |= !(res->flags & IORESOURCE_PREFETCH);
break;
case IORESOURCE_BUS:
*bus_range = res;
break;
}
}
if (res_valid)
return 0;
dev_err(dev, "non-prefetchable memory resource required\n");
return -EINVAL;
}
static void gen_pci_unmap_cfg(void *ptr)
{
pci_ecam_free((struct pci_config_window *)ptr);
}
static struct pci_config_window *gen_pci_init(struct device *dev,
struct list_head *resources, struct pci_ecam_ops *ops)
{
int err;
struct resource cfgres;
struct resource *bus_range = NULL;
struct pci_config_window *cfg;
/* Parse our PCI ranges and request their resources */
err = gen_pci_parse_request_of_pci_ranges(dev, resources, &bus_range);
if (err)
goto err_out;
err = of_address_to_resource(dev->of_node, 0, &cfgres);
if (err) {
dev_err(dev, "missing \"reg\" property\n");
goto err_out;
}
cfg = pci_ecam_create(dev, &cfgres, bus_range, ops);
if (IS_ERR(cfg)) {
err = PTR_ERR(cfg);
goto err_out;
}
err = devm_add_action(dev, gen_pci_unmap_cfg, cfg);
if (err) {
gen_pci_unmap_cfg(cfg);
goto err_out;
}
return cfg;
err_out:
pci_free_resource_list(resources);
return ERR_PTR(err);
}
int pci_host_common_probe(struct platform_device *pdev,
struct pci_ecam_ops *ops)
{
const char *type;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct pci_bus *bus, *child;
struct pci_host_bridge *bridge;
struct pci_config_window *cfg;
struct list_head resources;
int ret;
bridge = devm_pci_alloc_host_bridge(dev, 0);
if (!bridge)
return -ENOMEM;
type = of_get_property(np, "device_type", NULL);
if (!type || strcmp(type, "pci")) {
dev_err(dev, "invalid \"device_type\" %s\n", type);
return -EINVAL;
}
of_pci_check_probe_only();
/* Parse and map our Configuration Space windows */
INIT_LIST_HEAD(&resources);
cfg = gen_pci_init(dev, &resources, ops);
if (IS_ERR(cfg))
return PTR_ERR(cfg);
/* Do not reassign resources if probe only */
if (!pci_has_flag(PCI_PROBE_ONLY))
pci_add_flags(PCI_REASSIGN_ALL_RSRC | PCI_REASSIGN_ALL_BUS);
list_splice_init(&resources, &bridge->windows);
bridge->dev.parent = dev;
bridge->sysdata = cfg;
bridge->busnr = cfg->busr.start;
bridge->ops = &ops->pci_ops;
bridge->map_irq = of_irq_parse_and_map_pci;
bridge->swizzle_irq = pci_common_swizzle;
ret = pci_scan_root_bus_bridge(bridge);
if (ret < 0) {
dev_err(dev, "Scanning root bridge failed");
return ret;
}
bus = bridge->bus;
/*
* We insert PCI resources into the iomem_resource and
* ioport_resource trees in either pci_bus_claim_resources()
* or pci_bus_assign_resources().
*/
if (pci_has_flag(PCI_PROBE_ONLY)) {
pci_bus_claim_resources(bus);
} else {
pci_bus_size_bridges(bus);
pci_bus_assign_resources(bus);
list_for_each_entry(child, &bus->children, node)
pcie_bus_configure_settings(child);
}
pci_bus_add_devices(bus);
return 0;
}