[Mesa-dev] [PATCHv2 08/14] i965: Define and initialize image parameter structure.

[Pohjolainen, Topi]

On Mon, Jul 20, 2015 at 07:17:48PM +0300, Francisco Jerez wrote:
> This will be used to pass image meta-data to the shader when we cannot
> use typed surface reads and writes.  All entries except surface_idx
> and size are otherwise unused and will get eliminated by the uniform
> packing pass.  size will be used for bounds checking with some image
> formats and will be useful for ARB_shader_image_size too.  surface_idx
> is always used.
> 
> v2: Add CS support.  Move the image_params array back to
>     brw_stage_prog_data.
> ---
> I'm resending this (and also patches 9 and 10) because I had to make
> some rather intrusive changes during one of my last rebases -- The
> image_param array is now part of brw_stage_prog_data again instead of
> brw_stage_state (ironically as it was in my very first submission of
> these patches) because the compiler no longer has access to
> brw_stage_state since the brw_context pointer was removed from the
> visitors.
> 
>  src/mesa/drivers/dri/i965/brw_context.h          | 54 ++++++++++++++++
>  src/mesa/drivers/dri/i965/brw_cs.cpp             |  3 +
>  src/mesa/drivers/dri/i965/brw_gs.c               |  3 +
>  src/mesa/drivers/dri/i965/brw_vs.c               |  5 +-
>  src/mesa/drivers/dri/i965/brw_wm.c               |  4 ++
>  src/mesa/drivers/dri/i965/brw_wm_surface_state.c | 82 ++++++++++++++++++++++++
>  6 files changed, 150 insertions(+), 1 deletion(-)
> 
> diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
> index e16ad10..9ebad5b 100644
> --- a/src/mesa/drivers/dri/i965/brw_context.h
> +++ b/src/mesa/drivers/dri/i965/brw_context.h
> @@ -361,6 +361,7 @@ struct brw_stage_prog_data {
>  
>     GLuint nr_params;       /**< number of float params/constants */
>     GLuint nr_pull_params;
> +   unsigned nr_image_params;
>  
>     unsigned curb_read_length;
>     unsigned total_scratch;
> @@ -381,6 +382,59 @@ struct brw_stage_prog_data {
>      */
>     const gl_constant_value **param;
>     const gl_constant_value **pull_param;
> +
> +   /**
> +    * Image metadata passed to the shader as uniforms.  This is deliberately
> +    * ignored by brw_stage_prog_data_compare() because its contents don't have
> +    * any influence on program compilation.
> +    */
> +   struct brw_image_param *image_param;
> +};
> +
> +/*
> + * Image metadata structure as laid out in the shader parameter
> + * buffer.  Entries have to be 16B-aligned for the vec4 back-end to be
> + * able to use them.  That's okay because the padding and any unused
> + * entries [most of them except when we're doing untyped surface
> + * access] will be removed by the uniform packing pass.
> + */
> +#define BRW_IMAGE_PARAM_SURFACE_IDX_OFFSET      0
> +#define BRW_IMAGE_PARAM_OFFSET_OFFSET           4
> +#define BRW_IMAGE_PARAM_SIZE_OFFSET             8
> +#define BRW_IMAGE_PARAM_STRIDE_OFFSET           12
> +#define BRW_IMAGE_PARAM_TILING_OFFSET           16
> +#define BRW_IMAGE_PARAM_SWIZZLING_OFFSET        20
> +#define BRW_IMAGE_PARAM_SIZE                    24
> +
> +struct brw_image_param {
> +   /** Surface binding table index. */
> +   uint32_t surface_idx;
> +
> +   /** Surface X, Y and Z dimensions. */
> +   uint32_t size[3];
> +
> +   /** Offset applied to the X and Y surface coordinates. */
> +   uint32_t offset[2];
> +
> +   /** X-stride in bytes, Y-stride in bytes, horizontal slice stride in
> +    * pixels, vertical slice stride in pixels.
> +    */
> +   uint32_t stride[4];
> +
> +   /** Log2 of the tiling modulus in the X, Y and Z dimension. */
> +   uint32_t tiling[3];
> +
> +   /**
> +    * Right shift to apply for bit 6 address swizzling.  Two different
> +    * swizzles can be specified and will be applied one after the other.  The
> +    * resulting address will be:
> +    *
> +    *  addr' = addr ^ ((1 << 6) & ((addr >> swizzling[0]) ^
> +    *                              (addr >> swizzling[1])))
> +    *
> +    * Use \c 0xff if any of the swizzles is not required.
> +    */
> +   uint32_t swizzling[2];

I couldn't find any patches actually reading the swizzle values (only found
writes to it). Hence I checked your branch "image-load-store-lower" and still
couldn't find any users for it. Could you help me?