[PATCH 19/22] PCI: cpqphp: Use RESPONSE_IS_PCI_ERROR() to check read from hardware
From: Naveen Naidu <hidden>
Date: 2021-10-11 18:11:24
Also in:
linux-pci, lkml
Subsystem:
pci subsystem, the rest · Maintainers:
Bjorn Helgaas, Linus Torvalds
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 RESPONSE_IS_PCI_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 <redacted> --- 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 1b26ca0b3701..d5274b9b06a5 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 (RESPONSE_IS_PCI_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 (!RESPONSE_IS_PCI_ERROR(&ID)) { /* device present */ /* Setup slot structure. */ new_slot = cpqhp_slot_create(hold_bus_node->base);
--
2.25.1
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees