linuxdebug/arch/arm64/kernel/pci.c

236 lines
5.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Code borrowed from powerpc/kernel/pci-common.c
*
* Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
* Copyright (C) 2014 ARM Ltd.
*/
#include <linux/acpi.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/pci-acpi.h>
#include <linux/pci-ecam.h>
#include <linux/slab.h>
#ifdef CONFIG_ACPI
/*
* Try to assign the IRQ number when probing a new device
*/
int pcibios_alloc_irq(struct pci_dev *dev)
{
if (!acpi_disabled)
acpi_pci_irq_enable(dev);
return 0;
}
#endif
/*
* raw_pci_read/write - Platform-specific PCI config space access.
*/
int raw_pci_read(unsigned int domain, unsigned int bus,
unsigned int devfn, int reg, int len, u32 *val)
{
struct pci_bus *b = pci_find_bus(domain, bus);
if (!b)
return PCIBIOS_DEVICE_NOT_FOUND;
return b->ops->read(b, devfn, reg, len, val);
}
int raw_pci_write(unsigned int domain, unsigned int bus,
unsigned int devfn, int reg, int len, u32 val)
{
struct pci_bus *b = pci_find_bus(domain, bus);
if (!b)
return PCIBIOS_DEVICE_NOT_FOUND;
return b->ops->write(b, devfn, reg, len, val);
}
#ifdef CONFIG_NUMA
int pcibus_to_node(struct pci_bus *bus)
{
return dev_to_node(&bus->dev);
}
EXPORT_SYMBOL(pcibus_to_node);
#endif
#ifdef CONFIG_ACPI
struct acpi_pci_generic_root_info {
struct acpi_pci_root_info common;
struct pci_config_window *cfg; /* config space mapping */
};
int acpi_pci_bus_find_domain_nr(struct pci_bus *bus)
{
struct pci_config_window *cfg = bus->sysdata;
struct acpi_device *adev = to_acpi_device(cfg->parent);
struct acpi_pci_root *root = acpi_driver_data(adev);
return root->segment;
}
int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
{
struct pci_config_window *cfg;
struct acpi_device *adev;
struct device *bus_dev;
if (acpi_disabled)
return 0;
cfg = bridge->bus->sysdata;
/*
* On Hyper-V there is no corresponding ACPI device for a root bridge,
* therefore ->parent is set as NULL by the driver. And set 'adev' as
* NULL in this case because there is no proper ACPI device.
*/
if (!cfg->parent)
adev = NULL;
else
adev = to_acpi_device(cfg->parent);
bus_dev = &bridge->bus->dev;
ACPI_COMPANION_SET(&bridge->dev, adev);
set_dev_node(bus_dev, acpi_get_node(acpi_device_handle(adev)));
return 0;
}
static int pci_acpi_root_prepare_resources(struct acpi_pci_root_info *ci)
{
struct resource_entry *entry, *tmp;
int status;
status = acpi_pci_probe_root_resources(ci);
resource_list_for_each_entry_safe(entry, tmp, &ci->resources) {
if (!(entry->res->flags & IORESOURCE_WINDOW))
resource_list_destroy_entry(entry);
}
return status;
}
/*
* Lookup the bus range for the domain in MCFG, and set up config space
* mapping.
*/
static struct pci_config_window *
pci_acpi_setup_ecam_mapping(struct acpi_pci_root *root)
{
struct device *dev = &root->device->dev;
struct resource *bus_res = &root->secondary;
u16 seg = root->segment;
const struct pci_ecam_ops *ecam_ops;
struct resource cfgres;
struct acpi_device *adev;
struct pci_config_window *cfg;
int ret;
ret = pci_mcfg_lookup(root, &cfgres, &ecam_ops);
if (ret) {
dev_err(dev, "%04x:%pR ECAM region not found\n", seg, bus_res);
return NULL;
}
adev = acpi_resource_consumer(&cfgres);
if (adev)
dev_info(dev, "ECAM area %pR reserved by %s\n", &cfgres,
dev_name(&adev->dev));
else
dev_warn(dev, FW_BUG "ECAM area %pR not reserved in ACPI namespace\n",
&cfgres);
cfg = pci_ecam_create(dev, &cfgres, bus_res, ecam_ops);
if (IS_ERR(cfg)) {
dev_err(dev, "%04x:%pR error %ld mapping ECAM\n", seg, bus_res,
PTR_ERR(cfg));
return NULL;
}
return cfg;
}
/* release_info: free resources allocated by init_info */
static void pci_acpi_generic_release_info(struct acpi_pci_root_info *ci)
{
struct acpi_pci_generic_root_info *ri;
ri = container_of(ci, struct acpi_pci_generic_root_info, common);
pci_ecam_free(ri->cfg);
kfree(ci->ops);
kfree(ri);
}
/* Interface called from ACPI code to setup PCI host controller */
struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
{
struct acpi_pci_generic_root_info *ri;
struct pci_bus *bus, *child;
struct acpi_pci_root_ops *root_ops;
struct pci_host_bridge *host;
ri = kzalloc(sizeof(*ri), GFP_KERNEL);
if (!ri)
return NULL;
root_ops = kzalloc(sizeof(*root_ops), GFP_KERNEL);
if (!root_ops) {
kfree(ri);
return NULL;
}
ri->cfg = pci_acpi_setup_ecam_mapping(root);
if (!ri->cfg) {
kfree(ri);
kfree(root_ops);
return NULL;
}
root_ops->release_info = pci_acpi_generic_release_info;
root_ops->prepare_resources = pci_acpi_root_prepare_resources;
root_ops->pci_ops = (struct pci_ops *)&ri->cfg->ops->pci_ops;
bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg);
if (!bus)
return NULL;
/* If we must preserve the resource configuration, claim now */
host = pci_find_host_bridge(bus);
if (host->preserve_config)
pci_bus_claim_resources(bus);
/*
* Assign whatever was left unassigned. If we didn't claim above,
* this will reassign everything.
*/
pci_assign_unassigned_root_bus_resources(bus);
list_for_each_entry(child, &bus->children, node)
pcie_bus_configure_settings(child);
return bus;
}
void pcibios_add_bus(struct pci_bus *bus)
{
acpi_pci_add_bus(bus);
}
void pcibios_remove_bus(struct pci_bus *bus)
{
acpi_pci_remove_bus(bus);
}
#endif