linux/drivers/pci/controller/pci-host-common.c
Jess 3a11167d91 PCI: host-generic: Avoid reporting incorrect 'missing reg property' error
When pci_host_common_ecam_create() calls of_address_to_resource(), it
assumes all errors are due to a missing "reg" property in the device tree
node, when they may be due to a malformed "reg" property.

This can manifest when running the qemu "virt" board with a 32-bit kernel
and `highmem=on` and leads to the very confusing error message:

  pci-host-generic 4010000000.pcie: host bridge /pcie@10000000 ranges:
  pci-host-generic 4010000000.pcie:       IO 0x003eff0000..0x003effffff -> 0x0000000000
  pci-host-generic 4010000000.pcie:      MEM 0x0010000000..0x003efeffff -> 0x0010000000
  pci-host-generic 4010000000.pcie:      MEM 0x8000000000..0xffffffffff -> 0x8000000000
  pci-host-generic 4010000000.pcie: missing "reg" property
  pci-host-generic 4010000000.pcie: probe with driver pci-host-generic failed with error -75

Make the error message more generic.

Link: https://www.qemu.org/docs/master/system/arm/virt.html
Signed-off-by: Jess <jess@jessie.cafe>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://patch.msgid.link/20260120004444.191093-1-jess@jessie.cafe
2026-02-06 16:44:00 -06:00

110 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Common library for PCI host controller drivers
*
* Copyright (C) 2014 ARM Limited
*
* Author: Will Deacon <will.deacon@arm.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/pci-ecam.h>
#include <linux/platform_device.h>
#include "pci-host-common.h"
static void gen_pci_unmap_cfg(void *ptr)
{
pci_ecam_free((struct pci_config_window *)ptr);
}
struct pci_config_window *pci_host_common_ecam_create(struct device *dev,
struct pci_host_bridge *bridge, const struct pci_ecam_ops *ops)
{
int err;
struct resource cfgres;
struct resource_entry *bus;
struct pci_config_window *cfg;
err = of_address_to_resource(dev->of_node, 0, &cfgres);
if (err) {
dev_err(dev, "missing or malformed \"reg\" property\n");
return ERR_PTR(err);
}
bus = resource_list_first_type(&bridge->windows, IORESOURCE_BUS);
if (!bus)
return ERR_PTR(-ENODEV);
cfg = pci_ecam_create(dev, &cfgres, bus->res, ops);
if (IS_ERR(cfg))
return cfg;
err = devm_add_action_or_reset(dev, gen_pci_unmap_cfg, cfg);
if (err)
return ERR_PTR(err);
return cfg;
}
EXPORT_SYMBOL_GPL(pci_host_common_ecam_create);
int pci_host_common_init(struct platform_device *pdev,
struct pci_host_bridge *bridge,
const struct pci_ecam_ops *ops)
{
struct device *dev = &pdev->dev;
struct pci_config_window *cfg;
of_pci_check_probe_only();
platform_set_drvdata(pdev, bridge);
/* Parse and map our Configuration Space windows */
cfg = pci_host_common_ecam_create(dev, bridge, ops);
if (IS_ERR(cfg))
return PTR_ERR(cfg);
bridge->sysdata = cfg;
bridge->ops = (struct pci_ops *)&ops->pci_ops;
bridge->enable_device = ops->enable_device;
bridge->disable_device = ops->disable_device;
bridge->msi_domain = true;
return pci_host_probe(bridge);
}
EXPORT_SYMBOL_GPL(pci_host_common_init);
int pci_host_common_probe(struct platform_device *pdev)
{
const struct pci_ecam_ops *ops;
struct pci_host_bridge *bridge;
ops = of_device_get_match_data(&pdev->dev);
if (!ops)
return -ENODEV;
bridge = devm_pci_alloc_host_bridge(&pdev->dev, 0);
if (!bridge)
return -ENOMEM;
return pci_host_common_init(pdev, bridge, ops);
}
EXPORT_SYMBOL_GPL(pci_host_common_probe);
void pci_host_common_remove(struct platform_device *pdev)
{
struct pci_host_bridge *bridge = platform_get_drvdata(pdev);
pci_lock_rescan_remove();
pci_stop_root_bus(bridge->bus);
pci_remove_root_bus(bridge->bus);
pci_unlock_rescan_remove();
}
EXPORT_SYMBOL_GPL(pci_host_common_remove);
MODULE_DESCRIPTION("Common library for PCI host controller drivers");
MODULE_LICENSE("GPL v2");