[PATCH] pci-e: ignore unknown capability and continue searching

Zhang, Yanmin
2008-09-30T04:33:15Z

﻿Subject: pci-e: ignore unknown capability and continue searching
﻿From: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>

Tomasz reported AER driver couldn't work on his machine. With the output
of "lcpsi -vvv", I found the root port's extended capabilities are
Capabilities: [100] Unknown (11)
Capabilities: [150] Advanced Error Reporting
Capabilities: [190] Unknown (13)
Such Unknown capability is not expected. During pci-e initialization,function
get_port_device_capability just returns if it hits an unknown capability when
searching the AER capability.

I worked out a patch against 2.6.27-rc7. When hitting an unkown capability,
function get_port_device_capability continues the searching.

Tomasz tested it and the patch does work well.

Signed-off-by Zhang Yanmin <yanmin.zhang@linux.intel.com>
Reported-by Tomasz Czernecki <czernecki@gmail.com>

---

--- linux-2.6.27-rc7/drivers/pci/pcie/portdrv_core.c 2008-09-27 09:35:32.000000000 +0800
+++ linux-2.6.27-rc7_aer/drivers/pci/pcie/portdrv_core.c 2008-09-27 10:10:39.000000000 +0800
@@ -195,23 +195,25 @@ static int get_port_device_capability(st
/* PME Capable - root port capability */
if (((reg16 >> 4) & PORT_TYPE_MASK) == PCIE_RC_PORT)
services |= PCIE_PORT_SERVICE_PME;
-
+
pos = PCI_CFG_SPACE_SIZE;
while (pos) {
- pci_read_config_dword(dev, pos, &reg32);
- switch (reg32 & 0xffff) {
+ if (pci_read_config_dword(dev, pos, &reg32))
+ break;
+
+ /* some broken boards return ~0 */
+ if (reg32 == 0xffffffff)
+ break;
+
+ switch (PCI_EXT_CAP_ID(reg32)) {
case PCI_EXT_CAP_ID_ERR:
services |= PCIE_PORT_SERVICE_AER;
- pos = reg32 >> 20;
break;
case PCI_EXT_CAP_ID_VC:
services |= PCIE_PORT_SERVICE_VC;
- pos = reg32 >> 20;
- break;
- default:
- pos = 0;
break;
}
+ pos = PCI_EXT_CAP_NEXT(reg32);
}

return services;