[Mesa-dev] [PATCH v4 4/4] r600g: use do_endian_swap in texture swapping function

[Marek Olšák]

For the series:

Reviewed-by: Marek Olšák <marek.olsak at amd.com>

Marek

On Sat, Apr 23, 2016 at 11:36 AM, Oded Gabbay <oded.gabbay at gmail.com> wrote:
> For some texture formats we need to take "do_endian_swap" into account
> when configuring their swizzling.
>
> Signed-off-by: Oded Gabbay <oded.gabbay at gmail.com>
> ---
>  src/gallium/drivers/r600/r600_state_common.c | 35 +++++++++++++++++++++++++++-
>  1 file changed, 34 insertions(+), 1 deletion(-)
>
> diff --git a/src/gallium/drivers/r600/r600_state_common.c b/src/gallium/drivers/r600/r600_state_common.c
> index 21f71fc..e8ec20f 100644
> --- a/src/gallium/drivers/r600/r600_state_common.c
> +++ b/src/gallium/drivers/r600/r600_state_common.c
> @@ -2227,6 +2227,9 @@ uint32_t r600_translate_texformat(struct pipe_screen *screen,
>         bool is_srgb_valid = FALSE;
>         const unsigned char swizzle_xxxx[4] = {0, 0, 0, 0};
>         const unsigned char swizzle_yyyy[4] = {1, 1, 1, 1};
> +       const unsigned char swizzle_xxxy[4] = {0, 0, 0, 1};
> +       const unsigned char swizzle_zyx1[4] = {2, 1, 0, 5};
> +       const unsigned char swizzle_zyxw[4] = {2, 1, 0, 3};
>
>         int i;
>         const uint32_t sign_bit[4] = {
> @@ -2235,11 +2238,41 @@ uint32_t r600_translate_texformat(struct pipe_screen *screen,
>                 S_038010_FORMAT_COMP_Z(V_038010_SQ_FORMAT_COMP_SIGNED),
>                 S_038010_FORMAT_COMP_W(V_038010_SQ_FORMAT_COMP_SIGNED)
>         };
> +
> +       /* Need to replace the specified texture formats in case of big-endian.
> +        * These formats are formats that have channels with number of bits
> +        * not divisible by 8.
> +        * Mesa conversion functions don't swap bits for those formats, and because
> +        * we transmit this over a serial bus to the GPU (PCIe), the
> +        * bit-endianess is important!!!
> +        * In case we have an "opposite" format, just use that for the swizzling
> +        * information. If we don't have such an "opposite" format, we need
> +        * to use a fixed swizzle info instead (see below)
> +        */
> +       if (format == PIPE_FORMAT_R4A4_UNORM && do_endian_swap)
> +               format = PIPE_FORMAT_A4R4_UNORM;
> +
>         desc = util_format_description(format);
>
>         /* Depth and stencil swizzling is handled separately. */
>         if (desc->colorspace != UTIL_FORMAT_COLORSPACE_ZS) {
> -               word4 |= r600_get_swizzle_combined(desc->swizzle, swizzle_view, FALSE);
> +               /* Need to check for specific texture formats that don't have
> +                * an "opposite" format we can use. For those formats, we directly
> +                * specify the swizzling, which is the LE swizzling as defined in
> +                * u_format.csv
> +                */
> +               if (do_endian_swap) {
> +                       if (format == PIPE_FORMAT_L4A4_UNORM)
> +                               word4 |= r600_get_swizzle_combined(swizzle_xxxy, swizzle_view, FALSE);
> +                       else if (format == PIPE_FORMAT_B4G4R4A4_UNORM)
> +                               word4 |= r600_get_swizzle_combined(swizzle_zyxw, swizzle_view, FALSE);
> +                       else if (format == PIPE_FORMAT_B4G4R4X4_UNORM || format == PIPE_FORMAT_B5G6R5_UNORM)
> +                               word4 |= r600_get_swizzle_combined(swizzle_zyx1, swizzle_view, FALSE);
> +                       else
> +                               word4 |= r600_get_swizzle_combined(desc->swizzle, swizzle_view, FALSE);
> +               } else {
> +                       word4 |= r600_get_swizzle_combined(desc->swizzle, swizzle_view, FALSE);
> +               }
>         }
>
>         /* Colorspace (return non-RGB formats directly). */
> --
> 2.5.5
>