[PATCH v4 17/25] PCI: vmd: Use PCI_POSSIBLE_ERROR() to check read from hardware

From: Naveen Naidu
Date: Thu Nov 18 2021 - 09:09:00 EST

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.

Reviewed-by: Jonathan Derrick <jonathan.derrick@xxxxxxxxx>
Signed-off-by: Naveen Naidu <naveennaidu479@xxxxxxxxx>
drivers/pci/controller/vmd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index a45e8e59d3d4..515d05605204 100644
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -541,7 +541,7 @@ static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint,
int ret;

ret = pci_read_config_dword(dev, PCI_REG_VMLOCK, &vmlock);
- if (ret || vmlock == ~0)
+ if (ret || PCI_POSSIBLE_ERROR(vmlock))
return -ENODEV;

if (MB2_SHADOW_EN(vmlock)) {