Hi Fabio,
On 9 October 2015 at 14:36, Fabio Estevam festevam@gmail.com wrote:
On Fri, Oct 9, 2015 at 10:31 AM, Simon Glass sjg@chromium.org wrote:
If you look down one more level, these end up calling imx_pcie_read_config() which calls imx_pcie_addr_valid():
static int imx_pcie_addr_valid(pci_dev_t d) { if ((PCI_BUS(d) == 0) && (PCI_DEV(d) > 1)) return -EINVAL; if ((PCI_BUS(d) == 1) && (PCI_DEV(d) > 0)) return -EINVAL; return 0; }
I can understand the bus check, but why return an access error if the device does not exist on the bus? That seems like a bug to me.
Is your suggestion like this?
--- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -67,7 +67,7 @@ int pci_hose_read_config_##size##_via_dword(struct pci_control \ if (pci_hose_read_config_dword(hose, dev, offset & 0xfc, &val32) < 0) { *val = -1; \
return -1; \
return 0; \ } \ \ *val = (val32 >> ((offset & (int)off_mask) * 8));
Not really.
I don't understand the hardware so I don't know what exactly is wrong.
To me, imx_pcie_addr_valid() should ideally not fail when the device number is in range (0..31) but references a missing device. It should be possible for its caller (imx_pcie_read_config()) to read from that address and get 0xffff as expected.
If that works, then I'd suggest changing to imx_pcie_addr_valid() to ignore PCI_DEV(f).
If not, then I'd suggest changing imx_pcie_read_config() to return 0 even when imx_pcie_addr_valid() does not, and add a comment as to why the error is being squashed.
Regards, Simon