[PATCH v4 21/25] PCI: cpqphp: Use PCI_POSSIBLE_ERROR() to check read from hardware
From: Naveen Naidu
Date: Thu Nov 18 2021 - 09:09:24 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.
Signed-off-by: Naveen Naidu <naveennaidu479@xxxxxxxxx>
---
drivers/pci/hotplug/cpqphp_ctrl.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/hotplug/cpqphp_ctrl.c b/drivers/pci/hotplug/cpqphp_ctrl.c
index ed7b58eb64d2..93fd2a621822 100644
--- a/drivers/pci/hotplug/cpqphp_ctrl.c
+++ b/drivers/pci/hotplug/cpqphp_ctrl.c
@@ -2273,7 +2273,7 @@ static u32 configure_new_device(struct controller *ctrl, struct pci_func *func
while ((function < max_functions) && (!stop_it)) {
pci_bus_read_config_dword(ctrl->pci_bus, PCI_DEVFN(func->device, function), 0x00, &ID);
- if (ID == 0xFFFFFFFF) {
+ if (PCI_POSSIBLE_ERROR(ID)) {
function++;
} else {
/* Setup slot structure. */
@@ -2517,7 +2517,7 @@ static int configure_new_function(struct controller *ctrl, struct pci_func *func
pci_bus_read_config_dword(pci_bus, PCI_DEVFN(device, 0), 0x00, &ID);
pci_bus->number = func->bus;
- if (ID != 0xFFFFFFFF) { /* device present */
+ if (!PCI_POSSIBLE_ERROR(ID)) { /* device present */
/* Setup slot structure. */
new_slot = cpqhp_slot_create(hold_bus_node->base);
--
2.25.1