Commit 8c6af6f0 authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

Merge branch 'pci/resource' 

  - Evaluate ACPI "PCI Boot Configuration"_DSM (Benjamin Herrenschmidt)

  - Don't auto-realloc if we're preserving firmware config (Benjamin
    Herrenschmidt)

  - Allow arm64 to reallocate resources if necessary (Benjamin
    Herrenschmidt)

  - Preserve firmware config on arm64 when desired (Benjamin Herrenschmidt)

  - Simplify resource distribution to hotplug bridges (Nicholas Johnson)

* pci/resource:
  PCI: Skip resource distribution when no hotplug bridges
  PCI: Simplify pci_bus_distribute_available_resources()
  arm64: PCI: Preserve firmware configuration when desired
  arm64: PCI: Allow resource reallocation if necessary
  PCI: Don't auto-realloc if we're preserving firmware config
  PCI/ACPI: Evaluate PCI Boot Configuration _DSM
parents 3306e99e 6a381ea6

arch/arm64/kernel/pci.c

+11 −2
Original line number Diff line number Diff line
@@ -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);

drivers/acpi/pci_root.c

+12 −0
Original line number Diff line number Diff line
@@ -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);

drivers/pci/setup-bus.c

+33 −27
Original line number Diff line number Diff line
@@ -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;
@@ -1860,16 +1865,6 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, 
	extend_bridge_window(bridge, mmio_pref_res, add_list,

			     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
@@ -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;
@@ -1905,21 +1928,6 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, 
			remaining_mmio_pref -= resource_size(res);

	}



	/*

	 * 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);

include/linux/pci-acpi.h

+4 −3
Original line number Diff line number Diff line
@@ -107,6 +107,7 @@ static inline void acpiphp_check_host_bridge(struct acpi_device *adev) { } 
#endif



extern const guid_t pci_acpi_dsm_guid;

#define IGNORE_PCI_BOOT_CONFIG_DSM	0x05

#define DEVICE_LABEL_DSM		0x07

#define RESET_DELAY_DSM			0x08

#define FUNCTION_DELAY_DSM		0x09

include/linux/pci.h

+2 −0
Original line number Diff line number Diff line
@@ -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,

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