[PATCH 03/22] PCI: thunder: Use SET_PCI_ERROR_RESPONSE() when device not found

From: Naveen Naidu
Date: Mon Oct 11 2021 - 13:45:38 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 SET_PCI_ERROR_RESPONSE() to set the error response, when a faulty
read occurs.

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

Signed-off-by: Naveen Naidu <naveennaidu479@xxxxxxxxx>
---
drivers/pci/controller/pci-thunder-ecam.c | 20 ++++++++++----------
drivers/pci/controller/pci-thunder-pem.c | 2 +-
2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/controller/pci-thunder-ecam.c b/drivers/pci/controller/pci-thunder-ecam.c
index ffd84656544f..4c57ad2aa9aa 100644
--- a/drivers/pci/controller/pci-thunder-ecam.c
+++ b/drivers/pci/controller/pci-thunder-ecam.c
@@ -42,7 +42,7 @@ static int handle_ea_bar(u32 e0, int bar, struct pci_bus *bus,
if (where_a == 0x4) {
addr = bus->ops->map_bus(bus, devfn, bar); /* BAR 0 */
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}
v = readl(addr);
@@ -57,7 +57,7 @@ static int handle_ea_bar(u32 e0, int bar, struct pci_bus *bus,

addr = bus->ops->map_bus(bus, devfn, bar); /* BAR 0 */
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}
barl_orig = readl(addr + 0);
@@ -73,7 +73,7 @@ static int handle_ea_bar(u32 e0, int bar, struct pci_bus *bus,
if (where_a == 0xc) {
addr = bus->ops->map_bus(bus, devfn, bar + 4); /* BAR 1 */
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}
v = readl(addr); /* EA entry-3. Base-H */
@@ -105,7 +105,7 @@ static int thunder_ecam_p2_config_read(struct pci_bus *bus, unsigned int devfn,

addr = bus->ops->map_bus(bus, devfn, where_a);
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}

@@ -136,7 +136,7 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn,

addr = bus->ops->map_bus(bus, devfn, 0xc);
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}

@@ -147,7 +147,7 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn,

addr = bus->ops->map_bus(bus, devfn, 8);
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}

@@ -177,7 +177,7 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn,

addr = bus->ops->map_bus(bus, devfn, 0);
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}

@@ -197,7 +197,7 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn,

addr = bus->ops->map_bus(bus, devfn, 0x70);
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}
/* E_CAP */
@@ -212,7 +212,7 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn,
if (where_a == 0xb0) {
addr = bus->ops->map_bus(bus, devfn, where_a);
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}
v = readl(addr);
@@ -269,7 +269,7 @@ static int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn,
if (where_a == 0x70) {
addr = bus->ops->map_bus(bus, devfn, where_a);
if (!addr) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}
v = readl(addr);
diff --git a/drivers/pci/controller/pci-thunder-pem.c b/drivers/pci/controller/pci-thunder-pem.c
index 0660b9da204f..a463a1b61f23 100644
--- a/drivers/pci/controller/pci-thunder-pem.c
+++ b/drivers/pci/controller/pci-thunder-pem.c
@@ -42,7 +42,7 @@ static int thunder_pem_bridge_read(struct pci_bus *bus, unsigned int devfn,
struct thunder_pem_pci *pem_pci = (struct thunder_pem_pci *)cfg->priv;

if (devfn != 0 || where >= 2048) {
- *val = ~0;
+ SET_PCI_ERROR_RESPONSE(val);
return PCIBIOS_DEVICE_NOT_FOUND;
}

--
2.25.1