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authorAndy Shevchenko <andriy.shevchenko@linux.intel.com>2015-07-29 11:16:47 +0200
committerThomas Gleixner <tglx@linutronix.de>2015-07-29 21:23:50 +0200
commit39d9b77b8debb4746e189aa5b61ae6e81ec5eab8 (patch)
tree0c9a3d55d2fcb918a9834fa3e1d0edaa5b935914 /arch/x86
parentx86/platform/iosf_mbi: Add Intel Tangier PCI id (diff)
downloadlinux-39d9b77b8debb4746e189aa5b61ae6e81ec5eab8.tar.xz
linux-39d9b77b8debb4746e189aa5b61ae6e81ec5eab8.zip
x86/pci/intel_mid_pci: Work around for IRQ0 assignment
On Intel Tangier the MMC host controller is wired up to irq 0. But several other devices have irq 0 associated as well due to a bogus PCI configuration. The first initialized driver will acquire irq 0 and make it unavailable for other devices. If the sdhci driver is not the first one it will fail to acquire the interrupt and therefor be non functional. Add a quirk to the pci irq enable function which denies irq 0 to anything else than the MMC host controller driver on Tangier platforms. Fixes: 90b9aacf912a (serial: 8250_pci: add Intel Tangier support) Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Link: http://lkml.kernel.org/r/1438161409-4671-2-git-send-email-andriy.shevchenko@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/pci/intel_mid_pci.c24
1 files changed, 22 insertions, 2 deletions
diff --git a/arch/x86/pci/intel_mid_pci.c b/arch/x86/pci/intel_mid_pci.c
index 27062303c881..7553921c146c 100644
--- a/arch/x86/pci/intel_mid_pci.c
+++ b/arch/x86/pci/intel_mid_pci.c
@@ -35,6 +35,9 @@
#define PCIE_CAP_OFFSET 0x100
+/* Quirks for the listed devices */
+#define PCI_DEVICE_ID_INTEL_MRFL_MMC 0x1190
+
/* Fixed BAR fields */
#define PCIE_VNDR_CAP_ID_FIXED_BAR 0x00 /* Fixed BAR (TBD) */
#define PCI_FIXED_BAR_0_SIZE 0x04
@@ -214,10 +217,27 @@ static int intel_mid_pci_irq_enable(struct pci_dev *dev)
if (dev->irq_managed && dev->irq > 0)
return 0;
- if (intel_mid_identify_cpu() == INTEL_MID_CPU_CHIP_TANGIER)
+ switch (intel_mid_identify_cpu()) {
+ case INTEL_MID_CPU_CHIP_TANGIER:
polarity = 0; /* active high */
- else
+
+ /* Special treatment for IRQ0 */
+ if (dev->irq == 0) {
+ /*
+ * TNG has IRQ0 assigned to eMMC controller. But there
+ * are also other devices with bogus PCI configuration
+ * that have IRQ0 assigned. This check ensures that
+ * eMMC gets it.
+ */
+ if (dev->device != PCI_DEVICE_ID_INTEL_MRFL_MMC)
+ return -EBUSY;
+ }
+ break;
+ default:
polarity = 1; /* active low */
+ break;
+ }
+
ioapic_set_alloc_attr(&info, dev_to_node(&dev->dev), 1, polarity);
/*