[PATCH v3 8/8] PCI/AER: Include DEVCTL in aer_print_error()

[Naveen Naidu]

Print the contents of Device Control Register of the device which
detected the error. This might help in faster error diagnosis.

Sample output from dummy error injected by aer-inject:

  pcieport 0000:00:03.0: AER: Corrected error received: 0000:00:03.0
  pcieport 0000:00:03.0: PCIe Bus Error: severity=Corrected, type=Data Link 
Layer, (Receiver)
  pcieport 0000:00:03.0:   device [1b36:000c] error 
status/mask=00000040/0000e000, devctl=0x000f
  pcieport 0000:00:03.0:    [ 6] BadTLP

Signed-off-by: Naveen Naidu <naveennaidu...@gmail.com>
---
 drivers/pci/pci.h      |  2 ++
 drivers/pci/pcie/aer.c | 10 ++++++++--
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index eb88d8bfeaf7..48ed7f91113b 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -437,6 +437,8 @@ struct aer_err_info {
        u32 status;             /* COR/UNCOR Error Status */
        u32 mask;               /* COR/UNCOR Error Mask */
        struct aer_header_log_regs tlp; /* TLP Header */
+
+       u16 devctl;
 };
 
 /* Preliminary AER error information processed from Root port */
diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index 91f91d6ab052..42cae01b6887 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -729,8 +729,8 @@ void aer_print_error(struct pci_dev *dev, struct 
aer_err_info *info)
                   aer_error_severity_string[info->severity],
                   aer_error_layer[layer], aer_agent_string[agent]);
 
-       pci_printk(level, dev, "  device [%04x:%04x] error 
status/mask=%08x/%08x\n",
-                  dev->vendor, dev->device, info->status, info->mask);
+       pci_printk(level, dev, "  device [%04x:%04x] error 
status/mask=%08x/%08x, devctl=%#06x\n",
+                  dev->vendor, dev->device, info->status, info->mask, 
info->devctl);
 
        __aer_print_error(dev, info);
 
@@ -1083,6 +1083,12 @@ int aer_get_device_error_info(struct pci_dev *dev, 
struct aer_err_info *info)
        if (!aer)
                return 0;
 
+       /*
+        * Cache the value of Device Control Register now, because later the
+        * device might not be available
+        */
+       pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &info->devctl);
+
        if (info->severity == AER_CORRECTABLE) {
                pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS,
                        &info->status);
-- 
2.25.1