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: Tomasz Nowicki <tn@semihalf.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index 266a7b2..4f0e3eb 100644 (file)
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -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));

diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
index b5b376e..ffcc651 100644 (file)
--- a/drivers/acpi/pci_mcfg.c
+++ b/drivers/acpi/pci_mcfg.c
@@ -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;
 }
 

diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
index 7d63a66..7a4e83a 100644 (file)
--- a/include/linux/pci-acpi.h
+++ b/include/linux/pci-acpi.h
@@ -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)
 {