Merge tag 'pci-v3.17-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI fixes from Bjorn Helgaas:
 "These fix:

   - Boot video device detection on dual-GPU Apple systems
   - Hotplug fiascos on VGA switcheroo with radeon & nouveau drivers
   - Boot hang on Freescale i.MX6 systems
   - Excessive "no hotplug settings from platform" warnings

  In particular:

  Enumeration
    - Don't default exclusively to first video device (Bruno Prémont)

  PCI device hotplug
    - Remove "no hotplug settings from platform" warning (Bjorn Helgaas)
    - Add pci_ignore_hotplug() for VGA switcheroo (Bjorn Helgaas)

  Freescale i.MX6
    - Put LTSSM in "Detect" state before disabling (Lucas Stach)"

* tag 'pci-v3.17-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  vgaarb: Drop obsolete #ifndef
  vgaarb: Don't default exclusively to first video device with mem+io
  ACPIPHP / radeon / nouveau: Remove acpi_bus_no_hotplug()
  PCI: Remove "no hotplug settings from platform" warning
  PCI: Add pci_ignore_hotplug() to ignore hotplug events for a device
  PCI: imx6: Put LTSSM in "Detect" state before disabling it
  MAINTAINERS: Add Lucas Stach as co-maintainer for i.MX6 PCI driver

4 files changed, 57 insertions, 15 deletions

diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index a568efa..35fc73a 100644
--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -49,6 +49,9 @@ struct imx6_pcie {
 
 /* PCIe Port Logic registers (memory-mapped) */
 #define PL_OFFSET 0x700
+#define PCIE_PL_PFLR (PL_OFFSET + 0x08)
+#define PCIE_PL_PFLR_LINK_STATE_MASK		(0x3f << 16)
+#define PCIE_PL_PFLR_FORCE_LINK			(1 << 15)
 #define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
 #define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
 #define PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING	(1 << 29)
@@ -214,6 +217,32 @@ static int imx6q_pcie_abort_handler(unsigned long addr,
 static int imx6_pcie_assert_core_reset(struct pcie_port *pp)
 {
 	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+	u32 val, gpr1, gpr12;
+
+	/*
+	 * If the bootloader already enabled the link we need some special
+	 * handling to get the core back into a state where it is safe to
+	 * touch it for configuration.  As there is no dedicated reset signal
+	 * wired up for MX6QDL, we need to manually force LTSSM into "detect"
+	 * state before completely disabling LTSSM, which is a prerequisite
+	 * for core configuration.
+	 *
+	 * If both LTSSM_ENABLE and REF_SSP_ENABLE are active we have a strong
+	 * indication that the bootloader activated the link.
+	 */
+	regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, &gpr1);
+	regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, &gpr12);
+
+	if ((gpr1 & IMX6Q_GPR1_PCIE_REF_CLK_EN) &&
+	    (gpr12 & IMX6Q_GPR12_PCIE_CTL_2)) {
+		val = readl(pp->dbi_base + PCIE_PL_PFLR);
+		val &= ~PCIE_PL_PFLR_LINK_STATE_MASK;
+		val |= PCIE_PL_PFLR_FORCE_LINK;
+		writel(val, pp->dbi_base + PCIE_PL_PFLR);
+
+		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+				IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
+	}
 
 	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
 			IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
@@ -589,6 +618,14 @@ static int __init imx6_pcie_probe(struct platform_device *pdev)
 	return 0;
 }
 
+static void imx6_pcie_shutdown(struct platform_device *pdev)
+{
+	struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
+
+	/* bring down link, so bootloader gets clean state in case of reboot */
+	imx6_pcie_assert_core_reset(&imx6_pcie->pp);
+}
+
 static const struct of_device_id imx6_pcie_of_match[] = {
 	{ .compatible = "fsl,imx6q-pcie", },
 	{},
@@ -601,6 +638,7 @@ static struct platform_driver imx6_pcie_driver = {
 		.owner	= THIS_MODULE,
 		.of_match_table = imx6_pcie_of_match,
 	},
+	.shutdown = imx6_pcie_shutdown,
 };
 
 /* Freescale PCIe driver does not allow module unload */
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 70741c8..6cd5160 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -560,19 +560,15 @@ static void disable_slot(struct acpiphp_slot *slot)
 	slot->flags &= (~SLOT_ENABLED);
 }
 
-static bool acpiphp_no_hotplug(struct acpi_device *adev)
-{
-	return adev && adev->flags.no_hotplug;
-}
-
 static bool slot_no_hotplug(struct acpiphp_slot *slot)
 {
-	struct acpiphp_func *func;
+	struct pci_bus *bus = slot->bus;
+	struct pci_dev *dev;
 
-	list_for_each_entry(func, &slot->funcs, sibling)
-		if (acpiphp_no_hotplug(func_to_acpi_device(func)))
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		if (PCI_SLOT(dev->devfn) == slot->device && dev->ignore_hotplug)
 			return true;
-
+	}
 	return false;
 }
 
@@ -645,7 +641,7 @@ static void trim_stale_devices(struct pci_dev *dev)
 
 		status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
 		alive = (ACPI_SUCCESS(status) && device_status_valid(sta))
-			|| acpiphp_no_hotplug(adev);
+			|| dev->ignore_hotplug;
 	}
 	if (!alive)
 		alive = pci_device_is_present(dev);
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 9da84b8..5e01ae3 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -506,6 +506,8 @@ static irqreturn_t pcie_isr(int irq, void *dev_id)
 {
 	struct controller *ctrl = (struct controller *)dev_id;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
+	struct pci_bus *subordinate = pdev->subordinate;
+	struct pci_dev *dev;
 	struct slot *slot = ctrl->slot;
 	u16 detected, intr_loc;
 
@@ -539,6 +541,16 @@ static irqreturn_t pcie_isr(int irq, void *dev_id)
 		wake_up(&ctrl->queue);
 	}
 
+	if (subordinate) {
+		list_for_each_entry(dev, &subordinate->devices, bus_list) {
+			if (dev->ignore_hotplug) {
+				ctrl_dbg(ctrl, "ignoring hotplug event %#06x (%s requested no hotplug)\n",
+					 intr_loc, pci_name(dev));
+				return IRQ_HANDLED;
+			}
+		}
+	}
+
 	if (!(intr_loc & ~PCI_EXP_SLTSTA_CC))
 		return IRQ_HANDLED;
 
diff --git a/drivers/pci/hotplug/pcihp_slot.c b/drivers/pci/hotplug/pcihp_slot.c
index e246a10..3e36ec8 100644
--- a/drivers/pci/hotplug/pcihp_slot.c
+++ b/drivers/pci/hotplug/pcihp_slot.c
@@ -46,7 +46,6 @@ static void program_hpp_type0(struct pci_dev *dev, struct hpp_type0 *hpp)
 		 */
 		if (pci_is_pcie(dev))
 			return;
-		dev_info(&dev->dev, "using default PCI settings\n");
 		hpp = &pci_default_type0;
 	}
 
@@ -153,7 +152,6 @@ void pci_configure_slot(struct pci_dev *dev)
 {
 	struct pci_dev *cdev;
 	struct hotplug_params hpp;
-	int ret;
 
 	if (!(dev->hdr_type == PCI_HEADER_TYPE_NORMAL ||
 			(dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
@@ -163,9 +161,7 @@ void pci_configure_slot(struct pci_dev *dev)
 	pcie_bus_configure_settings(dev->bus);
 
 	memset(&hpp, 0, sizeof(hpp));
-	ret = pci_get_hp_params(dev, &hpp);
-	if (ret)
-		dev_warn(&dev->dev, "no hotplug settings from platform\n");
+	pci_get_hp_params(dev, &hpp);
 
 	program_hpp_type2(dev, hpp.t2);
 	program_hpp_type1(dev, hpp.t1);