Re: [PATCH v4 2/6] PCI: rcar: Fix calculating mask for PCIEPAMR register

From: Bjorn Helgaas
Date: Wed Feb 12 2020 - 09:04:38 EST


On Sat, Feb 08, 2020 at 06:36:37PM +0000, Lad Prabhakar wrote:
> The mask value was calculated incorrectly for PCIEPAMR register if the
> size was less the 128bytes, this patch fixes the above by adding a check
> on size.

s/less the/less than/
s/128bytes,/128 bytes./
s/this patch fixes the above/Fix this issue/

> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> ---
> drivers/pci/controller/pcie-rcar.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c
> index d5568db..c76a92a 100644
> --- a/drivers/pci/controller/pcie-rcar.c
> +++ b/drivers/pci/controller/pcie-rcar.c
> @@ -71,7 +71,7 @@ void rcar_pcie_set_outbound(int win, void __iomem *base,
> /* Setup PCIe address space mappings for each resource */
> resource_size_t res_start;
> resource_size_t size;
> - u32 mask;
> + u32 mask = 0x0;
>
> rcar_pci_write_reg(base, 0x00000000, PCIEPTCTLR(win));
>
> @@ -80,7 +80,8 @@ void rcar_pcie_set_outbound(int win, void __iomem *base,
> * keeps things pretty simple.
> */
> size = resource_size(res);
> - mask = (roundup_pow_of_two(size) / SZ_128) - 1;
> + if (size > 128)
> + mask = (roundup_pow_of_two(size) / SZ_128) - 1;

I would put the "mask = 0x0" right here so it's all in one place,
i.e.,

if (size > 128)
mask = (roundup_pow_of_two(size) / SZ_128) - 1;
else
mask = 0x0;

> rcar_pci_write_reg(base, mask << 7, PCIEPAMR(win));
>
> if (!host) {
> --
> 2.7.4
>