[RFC PATCH] ARM64/PCI: Set dev->irq=0 before calling acpi_pci_irq_enable()

[Dongdong Liu <liudongdong3@huawei.com>]

The init value of dev->irq is from PCI_INTERRUPT_LINE register.The default
value of dev->irq usually is 255 before calling acpi_pci_irq_enable().
This will cause a problem When the platform does not support INTx well.
For example, we do not config _PRT on our HIP07 platform, we met irq 255
confilict.

The error message is as below.
snd_hda_intel 000d:33:00.1: PCI INT B: no GSI
snd_hda_intel 000d:33:00.1: enabling device (0000 -> 0002)
snd_hda_intel 000d:33:00.1: Force to snoop mode by module option
snd_hda_intel 000d:33:00.1: Device has broken 64-bit MSI but arch tried to
assign one above 4G
genirq: Flags mismatch irq 255. 00000001 (enahisic2i0-tx1) vs. 00000081
(snd_hda_intel:card0)
hns-nic HISI00C2:00 enahisic2i0: request irq(255) fail

enahisic2i0-tx1: this device is a platform device.
snd_hda_intel:card0: this device is a PCI device.

Signed-off-by: Dongdong Liu <liudongdong3@huawei.com>
---
 arch/arm64/kernel/pci.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index 0e2ea1c..6a77bef 100644
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -28,8 +28,11 @@
  */
 int pcibios_alloc_irq(struct pci_dev *dev)
 {
-	if (!acpi_disabled)
+	if (!acpi_disabled) {
+		dev->irq = 0;
 		acpi_pci_irq_enable(dev);
+	}
+
 
 	return 0;
 }
-- 
1.9.1