Merge tag 'pci-v4.1-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI changes from Bjorn Helgaas:
 "Enumeration
    - Read capability list as dwords, not bytes (Sean O. Stalley)

  Resource management
    - Don't check for PNP overlaps with unassigned PCI BARs (Bjorn Helgaas)
    - Mark invalid BARs as unassigned (Bjorn Helgaas)
    - Show driver, BAR#, and resource on pci_ioremap_bar() failure (Bjorn Helgaas)
    - Fail pci_ioremap_bar() on unassigned resources (Bjorn Helgaas)
    - Assign resources before drivers claim devices (Yijing Wang)
    - Claim bus resources before pci_bus_add_devices() (Yijing Wang)

  Power management
    - Optimize device state transition delays (Aaron Lu)
    - Don't clear ASPM bits when the FADT declares it's unsupported (Matthew Garrett)

  Virtualization
    - Add ACS quirks for Intel 1G NICs (Alex Williamson)

  IOMMU
    - Add ptr to OF node arg to of_iommu_configure() (Murali Karicheri)
    - Move of_dma_configure() to device.c to help re-use (Murali Karicheri)
    - Fix size when dma-range is not used (Murali Karicheri)
    - Add helper functions pci_get[put]_host_bridge_device() (Murali Karicheri)
    - Add of_pci_dma_configure() to update DMA configuration (Murali Karicheri)
    - Update DMA configuration from DT (Murali Karicheri)
    - dma-mapping: limit IOMMU mapping size (Murali Karicheri)
    - Calculate device DMA masks based on DT dma-range size (Murali Karicheri)

  ARM Versatile host bridge driver
    - Check for devm_ioremap_resource() failures (Jisheng Zhang)

  Broadcom iProc host bridge driver
    - Add Broadcom iProc PCIe driver (Ray Jui)

  Marvell MVEBU host bridge driver
    - Add suspend/resume support (Thomas Petazzoni)

  Renesas R-Car host bridge driver
    - Fix position of MSI enable bit (Nobuhiro Iwamatsu)
    - Write zeroes to reserved PCIEPARL bits (Nobuhiro Iwamatsu)
    - Change PCIEPARL and PCIEPARH to PCIEPALR and PCIEPAUR (Nobuhiro Iwamatsu)
    - Verify that mem_res is 64K-aligned (Nobuhiro Iwamatsu)

  Samsung Exynos host bridge driver
    - Fix INTx enablement statement termination error (Jaehoon Chung)

  Miscellaneous
    - Make a shareable UUID for PCI firmware ACPI _DSM (Aaron Lu)
    - Clarify policy for vendor IDs in pci.txt (Michael S. Tsirkin)"

* tag 'pci-v4.1-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (36 commits)
  PCI: Read capability list as dwords, not bytes
  PCI: layerscape: Simplify platform_get_resource_byname() failure checking
  PCI: keystone: Don't dereference possible NULL pointer
  PCI: versatile: Check for devm_ioremap_resource() failures
  PCI: Don't clear ASPM bits when the FADT declares it's unsupported
  PCI: Clarify policy for vendor IDs in pci.txt
  PCI/ACPI: Optimize device state transition delays
  PCI: Export pci_find_host_bridge() for use inside PCI core
  PCI: Make a shareable UUID for PCI firmware ACPI _DSM
  PCI: Fix typo in Thunderbolt kernel message
  PCI: exynos: Fix INTx enablement statement termination error
  PCI: iproc: Add Broadcom iProc PCIe support
  PCI: iproc: Add DT docs for Broadcom iProc PCIe driver
  PCI: Export symbols required for loadable host driver modules
  PCI: Add ACS quirks for Intel 1G NICs
  PCI: mvebu: Add suspend/resume support
  PCI: Cleanup control flow
  sparc/PCI: Claim bus resources before pci_bus_add_devices()
  PCI: Assign resources before drivers claim devices (pci_scan_root_bus())
  PCI: Fail pci_ioremap_bar() on unassigned resources
  ...

drivers/pci/pci-acpi.c

@@ -18,6 +18,15 @@
 #include <linux/pm_qos.h>
 #include "pci.h"
 
+/*
+ * The UUID is defined in the PCI Firmware Specification available here:
+ * https://www.pcisig.com/members/downloads/pcifw_r3_1_13Dec10.pdf
+ */
+const u8 pci_acpi_dsm_uuid[] = {
+	0xd0, 0x37, 0xc9, 0xe5, 0x53, 0x35, 0x7a, 0x4d,
+	0x91, 0x17, 0xea, 0x4d, 0x19, 0xc3, 0x43, 0x4d
+};
+
 phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
 {
 	acpi_status status = AE_NOT_EXIST;
@@ -531,11 +540,32 @@ static struct pci_platform_pm_ops acpi_pci_platform_pm = {
 
 void acpi_pci_add_bus(struct pci_bus *bus)
 {
+	union acpi_object *obj;
+	struct pci_host_bridge *bridge;
+
 	if (acpi_pci_disabled || !bus->bridge)
 		return;
 
 	acpi_pci_slot_enumerate(bus);
 	acpiphp_enumerate_slots(bus);
+
+	/*
+	 * For a host bridge, check its _DSM for function 8 and if
+	 * that is available, mark it in pci_host_bridge.
+	 */
+	if (!pci_is_root_bus(bus))
+		return;
+
+	obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), pci_acpi_dsm_uuid, 3,
+				RESET_DELAY_DSM, NULL);
+	if (!obj)
+		return;
+
+	if (obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 1) {
+		bridge = pci_find_host_bridge(bus);
+		bridge->ignore_reset_delay = 1;
+	}
+	ACPI_FREE(obj);
 }
 
 void acpi_pci_remove_bus(struct pci_bus *bus)
@@ -561,6 +591,57 @@ static struct acpi_device *acpi_pci_find_companion(struct device *dev)
 				      check_children);
 }
 
+/**
+ * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI
+ * @pdev: the PCI device whose delay is to be updated
+ * @adev: the companion ACPI device of this PCI device
+ *
+ * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM
+ * control method of either the device itself or the PCI host bridge.
+ *
+ * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
+ * host bridge.  If it returns one, the OS may assume that all devices in
+ * the hierarchy have already completed power-on reset delays.
+ *
+ * Function 9, "Device Readiness Durations," applies only to the object
+ * where it is located.  It returns delay durations required after various
+ * events if the device requires less time than the spec requires.  Delays
+ * from this function take precedence over the Reset Delay function.
+ *
+ * These _DSM functions are defined by the draft ECN of January 28, 2014,
+ * titled "ACPI additions for FW latency optimizations."
+ */
+static void pci_acpi_optimize_delay(struct pci_dev *pdev,
+				    acpi_handle handle)
+{
+	struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
+	int value;
+	union acpi_object *obj, *elements;
+
+	if (bridge->ignore_reset_delay)
+		pdev->d3cold_delay = 0;
+
+	obj = acpi_evaluate_dsm(handle, pci_acpi_dsm_uuid, 3,
+				FUNCTION_DELAY_DSM, NULL);
+	if (!obj)
+		return;
+
+	if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) {
+		elements = obj->package.elements;
+		if (elements[0].type == ACPI_TYPE_INTEGER) {
+			value = (int)elements[0].integer.value / 1000;
+			if (value < PCI_PM_D3COLD_WAIT)
+				pdev->d3cold_delay = value;
+		}
+		if (elements[3].type == ACPI_TYPE_INTEGER) {
+			value = (int)elements[3].integer.value / 1000;
+			if (value < PCI_PM_D3_WAIT)
+				pdev->d3_delay = value;
+		}
+	}
+	ACPI_FREE(obj);
+}
+
 static void pci_acpi_setup(struct device *dev)
 {
 	struct pci_dev *pci_dev = to_pci_dev(dev);
@@ -569,6 +650,8 @@ static void pci_acpi_setup(struct device *dev)
 	if (!adev)
 		return;
 
+	pci_acpi_optimize_delay(pci_dev, adev->handle);
+
 	pci_acpi_add_pm_notifier(adev, pci_dev);
 	if (!adev->wakeup.flags.valid)
 		return;