On Mon, 26 Oct 2015 10:18:14 -0700 Ray Jui <rjui@xxxxxxxxxxxx> wrote: > Hi Jisheng, > > On 10/26/2015 4:02 AM, Jisheng Zhang wrote: > > Inspired by Russell King's patch[1], I found current iproc also has the > > same issue of "reading 32-bits from the command register, modifying the > > command register, and then writing it back has the effect of clearing > > any status bits that were indicating at that time" as pointed out by > > Russell. This patch fix this issue by using the pci_generic_config_write. > > > > [1]http://www.spinics.net/lists/linux-pci/msg44869.html > > > > Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx> > > --- > > drivers/pci/host/pcie-iproc.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c > > index fe2efb1..0c423f2 100644 > > --- a/drivers/pci/host/pcie-iproc.c > > +++ b/drivers/pci/host/pcie-iproc.c > > @@ -111,7 +111,7 @@ static void __iomem *iproc_pcie_map_cfg_bus(struct pci_bus *bus, > > static struct pci_ops iproc_pcie_ops = { > > .map_bus = iproc_pcie_map_cfg_bus, > > .read = pci_generic_config_read32, > > - .write = pci_generic_config_write32, > > + .write = pci_generic_config_write, > > }; > > > > static void iproc_pcie_reset(struct iproc_pcie *pcie) > > > > I have already confirmed with the ASIC team that the current iProc PCIe > controller requires 32-bit aligned access into the configuration space > due to the way how it was integrated into various iProc SoCs including > NSP, Cygnus, and NS2. > > This change will prevent the driver from working properly. > > I've informed our ASIC team about this issue and all future iProc based > SoCs should be able to support 8-bit, 16-bit access and therefore > pci_generic_config_write/read can be used for those SoCs. > > Thanks, > > Ray Got it. Thanks for the information, Jisheng -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
