Commit 0cb0786b authored by Tomasz Nowicki's avatar Tomasz Nowicki Committed by Bjorn Helgaas

ARM64: PCI: Support ACPI-based PCI host controller

Implement pci_acpi_scan_root() and other arch-specific calls so ARM64 can
use ACPI to setup and enumerate PCI buses.

Use memory-mapped configuration space information from either the ACPI
_CBA method or the MCFG table and the ECAM library and generic ECAM config
accessor ops.

Implement acpi_pci_bus_find_domain_nr() to retrieve the domain number from
the acpi_pci_root structure.

Implement pcibios_add_bus() and pcibios_remove_bus() to call
acpi_pci_add_bus() and acpi_pci_remove_bus() for ACPI slot management and
other configuration.
Signed-off-by: default avatarTomasz Nowicki <tn@semihalf.com>
Signed-off-by: default avatarJayachandran C <jchandra@broadcom.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
parent f058f4fb
......@@ -3,6 +3,7 @@ config ARM64
select ACPI_CCA_REQUIRED if ACPI
select ACPI_GENERIC_GSI if ACPI
select ACPI_REDUCED_HARDWARE_ONLY if ACPI
select ACPI_MCFG if ACPI
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
select ARCH_HAS_ELF_RANDOMIZE
......@@ -96,6 +97,7 @@ config ARM64
select OF_EARLY_FLATTREE
select OF_NUMA if NUMA && OF
select OF_RESERVED_MEM
select PCI_ECAM if ACPI
select PERF_USE_VMALLOC
select POWER_RESET
select POWER_SUPPLY
......
......@@ -18,6 +18,8 @@
#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>
/*
......@@ -100,15 +102,123 @@ EXPORT_SYMBOL(pcibus_to_node);
#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)
{
if (!acpi_disabled) {
struct pci_config_window *cfg = bridge->bus->sysdata;
struct acpi_device *adev = to_acpi_device(cfg->parent);
ACPI_COMPANION_SET(&bridge->dev, adev);
}
return 0;
}
/* Root bridge scanning */
/*
* 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 resource *bus_res = &root->secondary;
u16 seg = root->segment;
struct pci_config_window *cfg;
struct resource cfgres;
unsigned int bsz;
/* Use address from _CBA if present, otherwise lookup MCFG */
if (!root->mcfg_addr)
root->mcfg_addr = pci_mcfg_lookup(seg, bus_res);
if (!root->mcfg_addr) {
dev_err(&root->device->dev, "%04x:%pR ECAM region not found\n",
seg, bus_res);
return NULL;
}
bsz = 1 << pci_generic_ecam_ops.bus_shift;
cfgres.start = root->mcfg_addr + bus_res->start * bsz;
cfgres.end = cfgres.start + resource_size(bus_res) * bsz - 1;
cfgres.flags = IORESOURCE_MEM;
cfg = pci_ecam_create(&root->device->dev, &cfgres, bus_res,
&pci_generic_ecam_ops);
if (IS_ERR(cfg)) {
dev_err(&root->device->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(ri);
}
static struct acpi_pci_root_ops acpi_pci_root_ops = {
.release_info = pci_acpi_generic_release_info,
};
/* Interface called from ACPI code to setup PCI host controller */
struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
{
/* TODO: Should be revisited when implementing PCI on ACPI */
return NULL;
int node = acpi_get_node(root->device->handle);
struct acpi_pci_generic_root_info *ri;
struct pci_bus *bus, *child;
ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node);
if (!ri)
return NULL;
ri->cfg = pci_acpi_setup_ecam_mapping(root);
if (!ri->cfg) {
kfree(ri);
return NULL;
}
acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops;
bus = acpi_pci_root_create(root, &acpi_pci_root_ops, &ri->common,
ri->cfg);
if (!bus)
return NULL;
pci_bus_size_bridges(bus);
pci_bus_assign_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
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