Merge tag 'pci-v3.14-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI changes for the v3.14 merge window:

  Resource management
    - Change pci_bus_region addresses to dma_addr_t (Bjorn Helgaas)
    - Support 64-bit AGP BARs (Bjorn Helgaas, Yinghai Lu)
    - Add pci_bus_address() to get bus address of a BAR (Bjorn Helgaas)
    - Use pci_resource_start() for CPU address of AGP BARs (Bjorn Helgaas)
    - Enforce bus address limits in resource allocation (Yinghai Lu)
    - Allocate 64-bit BARs above 4G when possible (Yinghai Lu)
    - Convert pcibios_resource_to_bus() to take pci_bus, not pci_dev (Yinghai Lu)

  PCI device hotplug
    - Major rescan/remove locking update (Rafael J. Wysocki)
    - Make ioapic builtin only (not modular) (Yinghai Lu)
    - Fix release/free issues (Yinghai Lu)
    - Clean up pciehp (Bjorn Helgaas)
    - Announce pciehp slot info during enumeration (Bjorn Helgaas)

  MSI
    - Add pci_msi_vec_count(), pci_msix_vec_count() (Alexander Gordeev)
    - Add pci_enable_msi_range(), pci_enable_msix_range() (Alexander Gordeev)
    - Deprecate "tri-state" interfaces: fail/success/fail+info (Alexander Gordeev)
    - Export MSI mode using attributes, not kobjects (Greg Kroah-Hartman)
    - Drop "irq" param from *_restore_msi_irqs() (DuanZhenzhong)

  SR-IOV
    - Clear NumVFs when disabling SR-IOV in sriov_init() (ethan.zhao)

  Virtualization
    - Add support for save/restore of extended capabilities (Alex Williamson)
    - Add Virtual Channel to save/restore support (Alex Williamson)
    - Never treat a VF as a multifunction device (Alex Williamson)
    - Add pci_try_reset_function(), et al (Alex Williamson)

  AER
    - Ignore non-PCIe error sources (Betty Dall)
    - Support ACPI HEST error sources for domains other than 0 (Betty Dall)
    - Consolidate HEST error source parsers (Bjorn Helgaas)
    - Add a TLP header print helper (Borislav Petkov)

  Freescale i.MX6
    - Remove unnecessary code (Fabio Estevam)
    - Make reset-gpio optional (Marek Vasut)
    - Report "link up" only after link training completes (Marek Vasut)
    - Start link in Gen1 before negotiating for Gen2 mode (Marek Vasut)
    - Fix PCIe startup code (Richard Zhu)

  Marvell MVEBU
    - Remove duplicate of_clk_get_by_name() call (Andrew Lunn)
    - Drop writes to bridge Secondary Status register (Jason Gunthorpe)
    - Obey bridge PCI_COMMAND_MEM and PCI_COMMAND_IO bits (Jason Gunthorpe)
    - Support a bridge with no IO port window (Jason Gunthorpe)
    - Use max_t() instead of max(resource_size_t,) (Jingoo Han)
    - Remove redundant of_match_ptr (Sachin Kamat)
    - Call pci_ioremap_io() at startup instead of dynamically (Thomas Petazzoni)

  NVIDIA Tegra
    - Disable Gen2 for Tegra20 and Tegra30 (Eric Brower)

  Renesas R-Car
    - Add runtime PM support (Valentine Barshak)
    - Fix rcar_pci_probe() return value check (Wei Yongjun)

  Synopsys DesignWare
    - Fix crash in dw_msi_teardown_irq() (Bjørn Erik Nilsen)
    - Remove redundant call to pci_write_config_word() (Bjørn Erik Nilsen)
    - Fix missing MSI IRQs (Harro Haan)
    - Add dw_pcie prefix before cfg_read/write (Pratyush Anand)
    - Fix I/O transfers by using CPU (not realio) address (Pratyush Anand)
    - Whitespace cleanup (Jingoo Han)

  EISA
    - Call put_device() if device_register() fails (Levente Kurusa)
    - Revert EISA initialization breakage ((Bjorn Helgaas)

  Miscellaneous
    - Remove unused code, including PCIe 3.0 interfaces (Stephen Hemminger)
    - Prevent bus conflicts while checking for bridge apertures (Bjorn Helgaas)
    - Stop clearing bridge Secondary Status when setting up I/O aperture (Bjorn Helgaas)
    - Use dev_is_pci() to identify PCI devices (Yijing Wang)
    - Deprecate DEFINE_PCI_DEVICE_TABLE (Joe Perches)
    - Update documentation 00-INDEX (Erik Ekman)"

* tag 'pci-v3.14-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (119 commits)
  Revert "EISA: Initialize device before its resources"
  Revert "EISA: Log device resources in dmesg"
  vfio-pci: Use pci "try" reset interface
  PCI: Check parent kobject in pci_destroy_dev()
  xen/pcifront: Use global PCI rescan-remove locking
  powerpc/eeh: Use global PCI rescan-remove locking
  PCI: Fix pci_check_and_unmask_intx() comment typos
  PCI: Add pci_try_reset_function(), pci_try_reset_slot(), pci_try_reset_bus()
  MPT / PCI: Use pci_stop_and_remove_bus_device_locked()
  platform / x86: Use global PCI rescan-remove locking
  PCI: hotplug: Use global PCI rescan-remove locking
  pcmcia: Use global PCI rescan-remove locking
  ACPI / hotplug / PCI: Use global PCI rescan-remove locking
  ACPI / PCI: Use global PCI rescan-remove locking in PCI root hotplug
  PCI: Add global pci_lock_rescan_remove()
  PCI: Cleanup pci.h whitespace
  PCI: Reorder so actual code comes before stubs
  PCI/AER: Support ACPI HEST AER error sources for PCI domains other than 0
  ACPICA: Add helper macros to extract bus/segment numbers from HEST table.
  PCI: Make local functions static
  ...

1 files changed, 35 insertions, 21 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 74911c2cb1d..dc2756fb6f3 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -1148,26 +1148,40 @@ static inline void ahci_gtf_filter_workaround(struct ata_host *host)
 {}
 #endif
 
-static int ahci_init_interrupts(struct pci_dev *pdev, struct ahci_host_priv *hpriv)
+static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
+			 struct ahci_host_priv *hpriv)
 {
-	int rc;
-	unsigned int maxvec;
+	int rc, nvec;
 
-	if (!(hpriv->flags & AHCI_HFLAG_NO_MSI)) {
-		rc = pci_enable_msi_block_auto(pdev, &maxvec);
-		if (rc > 0) {
-			if ((rc == maxvec) || (rc == 1))
-				return rc;
-			/*
-			 * Assume that advantage of multipe MSIs is negated,
-			 * so fallback to single MSI mode to save resources
-			 */
-			pci_disable_msi(pdev);
-			if (!pci_enable_msi(pdev))
-				return 1;
-		}
-	}
+	if (hpriv->flags & AHCI_HFLAG_NO_MSI)
+		goto intx;
+
+	rc = pci_msi_vec_count(pdev);
+	if (rc < 0)
+		goto intx;
+
+	/*
+	 * If number of MSIs is less than number of ports then Sharing Last
+	 * Message mode could be enforced. In this case assume that advantage
+	 * of multipe MSIs is negated and use single MSI mode instead.
+	 */
+	if (rc < n_ports)
+		goto single_msi;
+
+	nvec = rc;
+	rc = pci_enable_msi_block(pdev, nvec);
+	if (rc)
+		goto intx;
 
+	return nvec;
+
+single_msi:
+	rc = pci_enable_msi(pdev);
+	if (rc)
+		goto intx;
+	return 1;
+
+intx:
 	pci_intx(pdev, 1);
 	return 0;
 }
@@ -1328,10 +1342,6 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	hpriv->mmio = pcim_iomap_table(pdev)[ahci_pci_bar];
 
-	n_msis = ahci_init_interrupts(pdev, hpriv);
-	if (n_msis > 1)
-		hpriv->flags |= AHCI_HFLAG_MULTI_MSI;
-
 	/* save initial config */
 	ahci_pci_save_initial_config(pdev, hpriv);
 
@@ -1386,6 +1396,10 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	 */
 	n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));
 
+	n_msis = ahci_init_interrupts(pdev, n_ports, hpriv);
+	if (n_msis > 1)
+		hpriv->flags |= AHCI_HFLAG_MULTI_MSI;
+
 	host = ata_host_alloc_pinfo(&pdev->dev, ppi, n_ports);
 	if (!host)
 		return -ENOMEM;