Re: [PATCH] PCI: iproc: Fix incorrect MSI address alignment

From: Bjorn Helgaas
Date: Wed Nov 23 2016 - 18:16:32 EST


On Mon, Nov 21, 2016 at 05:48:30PM -0800, Ray Jui wrote:
> In the code to handle PAXB v2 based MSI steering, the logic aligns the
> MSI register address to the size of supported inbound mapping range.
> This is incorrect since it rounds "up" the starting address to the next
> aligned address, but what we want is the starting address to be rounded
> "down" to the aligned address.
>
> This patch fixes the issue and allows MSI writes to be properly steered
> to the GIC
>
> Fixes: 4b073155fbd3 ("PCI: iproc: Add support for the next-gen PAXB
> controller")
>
> Signed-off-by: Ray Jui <ray.jui@xxxxxxxxxxxx>

Applied to pci/host-iproc for v4.10, thanks, Ray!

> ---
> 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 8ffb9d4..fb09668 100644
> --- a/drivers/pci/host/pcie-iproc.c
> +++ b/drivers/pci/host/pcie-iproc.c
> @@ -1018,7 +1018,7 @@ static int iproc_pcie_paxb_v2_msi_steer(struct iproc_pcie *pcie, u64 msi_addr)
>
> memset(&range, 0, sizeof(range));
> range.size = SZ_32K;
> - range.pci_addr = range.cpu_addr = ALIGN(msi_addr, range.size);
> + range.pci_addr = range.cpu_addr = msi_addr & ~(range.size - 1);
>
> ret = iproc_pcie_setup_ib(pcie, &range, IPROC_PCIE_IB_MAP_IO);
> return ret;
> --
> 2.1.4
>