Commit 13983eb8 authored by Tomasz Nowicki's avatar Tomasz Nowicki Committed by Bjorn Helgaas
Browse files

PCI/ACPI: Extend pci_mcfg_lookup() to return ECAM config accessors 



pci_mcfg_lookup() is the external interface to the generic MCFG code.
Previously it merely looked up the ECAM base address for a given domain and
bus range.  We want a way to add MCFG quirks, some of which may require
special config accessors and adjustments to the ECAM address range.

Extend pci_mcfg_lookup() so it can return a pointer to a pci_ecam_ops
structure and a struct resource for the ECAM address space.  For now, it
always returns &pci_generic_ecam_ops (the standard accessor) and the
resource described by the MCFG.

No functional changes intended.

[bhelgaas: changelog]
Signed-off-by: default avatarTomasz Nowicki <tn@semihalf.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 8fd4391e

arch/arm64/kernel/pci.c

+5 −12
Original line number Diff line number Diff line
@@ -137,25 +137,18 @@ 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;

	struct pci_ecam_ops *ecam_ops;

	struct resource cfgres;

	struct acpi_device *adev;

	struct pci_config_window *cfg;

	unsigned int bsz;

	int ret;



	/* 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) {

	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;

	}



	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;



	adev = acpi_resource_consumer(&cfgres);

	if (adev)

		dev_info(dev, "ECAM area %pR reserved by %s\n", &cfgres,
@@ -164,7 +157,7 @@ pci_acpi_setup_ecam_mapping(struct acpi_pci_root *root) 
		dev_warn(dev, FW_BUG "ECAM area %pR not reserved in ACPI namespace\n",

			 &cfgres);



	cfg = pci_ecam_create(dev, &cfgres, bus_res, &pci_generic_ecam_ops);

	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));

drivers/acpi/pci_mcfg.c

+25 −3
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ 
#include <linux/kernel.h>

#include <linux/pci.h>

#include <linux/pci-acpi.h>

#include <linux/pci-ecam.h>



/* Structure to hold entries from the MCFG table */

struct mcfg_entry {
@@ -35,9 +36,18 @@ struct mcfg_entry { 
/* List to save MCFG entries */

static LIST_HEAD(pci_mcfg_list);



phys_addr_t pci_mcfg_lookup(u16 seg, struct resource *bus_res)

int pci_mcfg_lookup(struct acpi_pci_root *root, struct resource *cfgres,

		    struct pci_ecam_ops **ecam_ops)

{

	struct pci_ecam_ops *ops = &pci_generic_ecam_ops;

	struct resource *bus_res = &root->secondary;

	u16 seg = root->segment;

	struct mcfg_entry *e;

	struct resource res;



	/* Use address from _CBA if present, otherwise lookup MCFG */

	if (root->mcfg_addr)

		goto skip_lookup;



	/*

	 * We expect exact match, unless MCFG entry end bus covers more than
@@ -45,10 +55,22 @@ phys_addr_t pci_mcfg_lookup(u16 seg, struct resource *bus_res) 
	 */

	list_for_each_entry(e, &pci_mcfg_list, list) {

		if (e->segment == seg && e->bus_start == bus_res->start &&

		    e->bus_end >= bus_res->end)

			return e->addr;

		    e->bus_end >= bus_res->end) {

			root->mcfg_addr = e->addr;

		}



	}



	if (!root->mcfg_addr)

		return -ENXIO;



skip_lookup:

	memset(&res, 0, sizeof(res));

	res.start = root->mcfg_addr + (bus_res->start << 20);

	res.end = res.start + (resource_size(bus_res) << 20) - 1;

	res.flags = IORESOURCE_MEM;

	*cfgres = res;

	*ecam_ops = ops;

	return 0;

}

include/linux/pci-acpi.h

+3 −1
Original line number Diff line number Diff line
@@ -24,7 +24,9 @@ static inline acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev) 
}

extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle);



extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource *bus_res);

struct pci_ecam_ops;

extern int pci_mcfg_lookup(struct acpi_pci_root *root, struct resource *cfgres,

			   struct pci_ecam_ops **ecam_ops);



static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)

{

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