| Message ID | c576d5ab04e2f4d79c5eaa8f3564c3053c079716.1634306198.git.naveennaidu479@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Unify PCI error response checking | expand |
diff --git a/drivers/pci/controller/dwc/pci-exynos.c b/drivers/pci/controller/dwc/pci-exynos.c index c24dab383654..f9526d6de160 100644 --- a/drivers/pci/controller/dwc/pci-exynos.c +++ b/drivers/pci/controller/dwc/pci-exynos.c @@ -216,10 +216,8 @@ static int exynos_pcie_rd_own_conf(struct pci_bus *bus, unsigned int devfn, { struct dw_pcie *pci = to_dw_pcie_from_pp(bus->sysdata); - if (PCI_SLOT(devfn)) { - *val = ~0; + if (PCI_SLOT(devfn)) return PCIBIOS_DEVICE_NOT_FOUND; - } *val = dw_pcie_read_dbi(pci, where, size); return PCIBIOS_SUCCESSFUL;
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. The host controller drivers sets the error response values (~0) and returns an error when faulty hardware read occurs. But the error response value (~0) is already being set in PCI_OP_READ and PCI_USER_READ_CONFIG whenever a read by host controller driver fails. Thus, it's no longer necessary for the host controller drivers to fabricate any error response. This helps unify PCI error response checking and make error check consistent and easier to find. Signed-off-by: Naveen Naidu <naveennaidu479@gmail.com> --- drivers/pci/controller/dwc/pci-exynos.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)