diff options
| -rw-r--r-- | arch/arm64/kernel/pci.c | 13 | ||||
| -rw-r--r-- | drivers/acpi/pci_root.c | 12 | ||||
| -rw-r--r-- | drivers/pci/setup-bus.c | 60 | ||||
| -rw-r--r-- | include/linux/pci-acpi.h | 7 | ||||
| -rw-r--r-- | include/linux/pci.h | 2 |
5 files changed, 62 insertions, 32 deletions
diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c index bb85e2f4603f..16fcb8d72553 100644 --- a/arch/arm64/kernel/pci.c +++ b/arch/arm64/kernel/pci.c @@ -168,6 +168,7 @@ 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) @@ -193,8 +194,16 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) if (!bus) return NULL; - pci_bus_size_bridges(bus); - pci_bus_assign_resources(bus); + /* 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); diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index c36781a9b493..0d57f817ef1e 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -894,6 +894,7 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root, int node = acpi_get_node(device->handle); struct pci_bus *bus; struct pci_host_bridge *host_bridge; + union acpi_object *obj; info->root = root; info->bridge = device; @@ -930,6 +931,17 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root, if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL)) host_bridge->native_ltr = 0; + /* + * Evaluate the "PCI Boot Configuration" _DSM Function. If it + * exists and returns 0, we must preserve any PCI resource + * assignments made by firmware for this host bridge. + */ + obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1, + IGNORE_PCI_BOOT_CONFIG_DSM, NULL); + if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0) + host_bridge->preserve_config = 1; + ACPI_FREE(obj); + pci_scan_child_bus(bus); pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info, info); diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 0cdd5ff389de..79b1fa6519be 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1684,10 +1684,15 @@ static enum enable_type pci_realloc_detect(struct pci_bus *bus, enum enable_type enable_local) { bool unassigned = false; + struct pci_host_bridge *host; if (enable_local != undefined) return enable_local; + host = pci_find_host_bridge(bus); + if (host->preserve_config) + return auto_disabled; + pci_walk_bus(bus, iov_resources_unassigned, &unassigned); if (unassigned) return auto_enabled; @@ -1861,16 +1866,6 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, available_mmio_pref); /* - * Calculate the total amount of extra resource space we can - * pass to bridges below this one. This is basically the - * extra space reduced by the minimal required space for the - * non-hotplug bridges. - */ - remaining_io = available_io; - remaining_mmio = available_mmio; - remaining_mmio_pref = available_mmio_pref; - - /* * Calculate how many hotplug bridges and normal bridges there * are on this bus. We will distribute the additional available * resources between hotplug bridges. @@ -1882,6 +1877,34 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, normal_bridges++; } + /* + * There is only one bridge on the bus so it gets all available + * resources which it can then distribute to the possible hotplug + * bridges below. + */ + if (hotplug_bridges + normal_bridges == 1) { + dev = list_first_entry(&bus->devices, struct pci_dev, bus_list); + if (dev->subordinate) { + pci_bus_distribute_available_resources(dev->subordinate, + add_list, available_io, available_mmio, + available_mmio_pref); + } + return; + } + + if (hotplug_bridges == 0) + return; + + /* + * Calculate the total amount of extra resource space we can + * pass to bridges below this one. This is basically the + * extra space reduced by the minimal required space for the + * non-hotplug bridges. + */ + remaining_io = available_io; + remaining_mmio = available_mmio; + remaining_mmio_pref = available_mmio_pref; + for_each_pci_bridge(dev, bus) { const struct resource *res; @@ -1906,21 +1929,6 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, } /* - * There is only one bridge on the bus so it gets all available - * resources which it can then distribute to the possible hotplug - * bridges below. - */ - if (hotplug_bridges + normal_bridges == 1) { - dev = list_first_entry(&bus->devices, struct pci_dev, bus_list); - if (dev->subordinate) { - pci_bus_distribute_available_resources(dev->subordinate, - add_list, available_io, available_mmio, - available_mmio_pref); - } - return; - } - - /* * Go over devices on this bus and distribute the remaining * resource space between hotplug bridges. */ @@ -1936,8 +1944,6 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, * Distribute available extra resources equally between * hotplug-capable downstream ports taking alignment into * account. - * - * Here hotplug_bridges is always != 0. */ align = pci_resource_alignment(bridge, io_res); io = div64_ul(available_io, hotplug_bridges); diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h index 8082b612f561..62b7fdcc661c 100644 --- a/include/linux/pci-acpi.h +++ b/include/linux/pci-acpi.h @@ -107,9 +107,10 @@ static inline void acpiphp_check_host_bridge(struct acpi_device *adev) { } #endif extern const guid_t pci_acpi_dsm_guid; -#define DEVICE_LABEL_DSM 0x07 -#define RESET_DELAY_DSM 0x08 -#define FUNCTION_DELAY_DSM 0x09 +#define IGNORE_PCI_BOOT_CONFIG_DSM 0x05 +#define DEVICE_LABEL_DSM 0x07 +#define RESET_DELAY_DSM 0x08 +#define FUNCTION_DELAY_DSM 0x09 #else /* CONFIG_ACPI */ static inline void acpi_pci_add_bus(struct pci_bus *bus) { } diff --git a/include/linux/pci.h b/include/linux/pci.h index ea91e79d0ba6..bf6ea6fe39ff 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -508,6 +508,8 @@ struct pci_host_bridge { unsigned int native_shpc_hotplug:1; /* OS may use SHPC hotplug */ unsigned int native_pme:1; /* OS may use PCIe PME */ unsigned int native_ltr:1; /* OS may use PCIe LTR */ + unsigned int preserve_config:1; /* Preserve FW resource setup */ + /* Resource alignment requirements */ resource_size_t (*align_resource)(struct pci_dev *dev, const struct resource *res, |