diff mbox series

[v4,19/25] PCI/DPC: Use PCI_POSSIBLE_ERROR() to check read from hardware

Message ID 9b0632f1f183432149f495cf12bdd5a72cc597a4.1637243717.git.naveennaidu479@gmail.com (mailing list archive)
State Accepted
Headers show
Series Unify PCI error response checking | expand

Commit Message

Naveen Naidu Nov. 18, 2021, 2:03 p.m. UTC 
An MMIO read from a PCI device that doesn't exist or doesn't respond
causes a PCI error.  There's no real data to return to satisfy the
CPU read, so most hardware fabricates ~0 data.

Use PCI_POSSIBLE_ERROR() to check the response we get when we read
data from hardware.

This helps unify PCI error response checking and make error checks
consistent and easier to find.

Compile tested only.

Signed-off-by: Naveen Naidu <naveennaidu479@gmail.com>
---
 drivers/pci/pcie/dpc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
index c556e7beafe3..3e9afee02e8d 100644
--- a/drivers/pci/pcie/dpc.c
+++ b/drivers/pci/pcie/dpc.c
@@ -79,7 +79,7 @@  static bool dpc_completed(struct pci_dev *pdev)
 	u16 status;
 
 	pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_STATUS, &status);
-	if ((status != 0xffff) && (status & PCI_EXP_DPC_STATUS_TRIGGER))
+	if ((!PCI_POSSIBLE_ERROR(status)) && (status & PCI_EXP_DPC_STATUS_TRIGGER))
 		return false;
 
 	if (test_bit(PCI_DPC_RECOVERING, &pdev->priv_flags))
@@ -312,7 +312,7 @@  static irqreturn_t dpc_irq(int irq, void *context)
 
 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 
-	if (!(status & PCI_EXP_DPC_STATUS_INTERRUPT) || status == (u16)(~0))
+	if (!(status & PCI_EXP_DPC_STATUS_INTERRUPT) || PCI_POSSIBLE_ERROR(status))
 		return IRQ_NONE;
 
 	pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS,