[Mesa-dev] [PATCH] i965/Gen7: Fix HiZ ops for MSAA depth

Chris Forbes chrisf at ijw.co.nz
Sun Jun 15 14:17:38 PDT 2014


Ping.

This has been broken for ages, and at least tesseract is carrying
hacks to work around it (extra color buffer containing depth values,
in their g-buffer). Getting rid of that wins us about 15%.

-- Chris

On Sat, Feb 8, 2014 at 3:54 PM, Chris Forbes <chrisf at ijw.co.nz> wrote:
> Previously, we would program the sample count based on the blorp
> operation's dst sample count -- which is zero for a HiZ op; we'd also
> ignore the difference between physical and logical surface size for
> the depth surface.
>
> That kindof worked -- the two errors almost cancel out -- but produced
> strange blocky artifacts.
>
> Instead, program the sample count properly, and use the logical
> dimensions of the depth surface.
>
> Fixes broken rendering in `Tesseract` with msaa=4 glineardepth=0
>
> NOTE: I've hacked the BLORP depth alignment code a bit (at `Not quite
> sure ...`). This is almost certainly not the right thing.
>
> Signed-off-by: Chris Forbes <chrisf at ijw.co.nz>
> ---
>  src/mesa/drivers/dri/i965/gen7_blorp.cpp | 41 +++++++++++++++++++-------------
>  1 file changed, 25 insertions(+), 16 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/gen7_blorp.cpp b/src/mesa/drivers/dri/i965/gen7_blorp.cpp
> index 4bf9396..58dc497 100644
> --- a/src/mesa/drivers/dri/i965/gen7_blorp.cpp
> +++ b/src/mesa/drivers/dri/i965/gen7_blorp.cpp
> @@ -447,7 +447,8 @@ gen7_blorp_emit_streamout_disable(struct brw_context *brw,
>
>  static void
>  gen7_blorp_emit_sf_config(struct brw_context *brw,
> -                          const brw_blorp_params *params)
> +                          const brw_blorp_params *params,
> +                          int num_samples)
>  {
>     /* 3DSTATE_SF
>      *
> @@ -472,7 +473,7 @@ gen7_blorp_emit_sf_config(struct brw_context *brw,
>        OUT_BATCH(_3DSTATE_SF << 16 | (7 - 2));
>        OUT_BATCH(params->depth_format <<
>                  GEN7_SF_DEPTH_BUFFER_SURFACE_FORMAT_SHIFT);
> -      OUT_BATCH(params->dst.num_samples > 1 ? GEN6_SF_MSRAST_ON_PATTERN : 0);
> +      OUT_BATCH(num_samples > 1 ? GEN6_SF_MSRAST_ON_PATTERN : 0);
>        OUT_BATCH(0);
>        OUT_BATCH(0);
>        OUT_BATCH(0);
> @@ -500,7 +501,8 @@ gen7_blorp_emit_sf_config(struct brw_context *brw,
>  static void
>  gen7_blorp_emit_wm_config(struct brw_context *brw,
>                            const brw_blorp_params *params,
> -                          brw_blorp_prog_data *prog_data)
> +                          brw_blorp_prog_data *prog_data,
> +                          int num_samples)
>  {
>     uint32_t dw1 = 0, dw2 = 0;
>
> @@ -528,7 +530,7 @@ gen7_blorp_emit_wm_config(struct brw_context *brw,
>        dw1 |= GEN7_WM_DISPATCH_ENABLE; /* We are rendering */
>     }
>
> -      if (params->dst.num_samples > 1) {
> +      if (num_samples > 1) {
>           dw1 |= GEN7_WM_MSRAST_ON_PATTERN;
>           if (prog_data && prog_data->persample_msaa_dispatch)
>              dw2 |= GEN7_WM_MSDISPMODE_PERSAMPLE;
> @@ -562,7 +564,8 @@ static void
>  gen7_blorp_emit_ps_config(struct brw_context *brw,
>                            const brw_blorp_params *params,
>                            uint32_t prog_offset,
> -                          brw_blorp_prog_data *prog_data)
> +                          brw_blorp_prog_data *prog_data,
> +                          int num_samples)
>  {
>     uint32_t dw2, dw4, dw5;
>     const int max_threads_shift = brw->is_haswell ?
> @@ -579,8 +582,10 @@ gen7_blorp_emit_ps_config(struct brw_context *brw,
>      */
>     dw4 |= GEN7_PS_16_DISPATCH_ENABLE;
>
> -   if (brw->is_haswell)
> -      dw4 |= SET_FIELD(1, HSW_PS_SAMPLE_MASK); /* 1 sample for now */
> +   if (brw->is_haswell) {
> +      int sample_mask = (num_samples > 1) ? (1 << num_samples) - 1 : 1;
> +      dw4 |= SET_FIELD(sample_mask, HSW_PS_SAMPLE_MASK);
> +   }
>     if (params->use_wm_prog) {
>        dw2 |= 1 << GEN7_PS_SAMPLER_COUNT_SHIFT; /* Up to 4 samplers */
>        dw4 |= GEN7_PS_PUSH_CONSTANT_ENABLE;
> @@ -714,7 +719,9 @@ gen7_blorp_emit_depth_stencil_config(struct brw_context *brw,
>
>     lod = params->depth.level - params->depth.mt->first_level;
>
> -   if (params->hiz_op != GEN6_HIZ_OP_NONE && lod == 0) {
> +   /* not quite sure about the MSAA interaction here! */
> +   if (params->hiz_op != GEN6_HIZ_OP_NONE && lod == 0 &&
> +         params->depth.mt->num_samples <= 1) {
>        /* HIZ ops for lod 0 may set the width & height a little
>         * larger to allow the fast depth clear to fit the hardware
>         * alignment requirements. (8x4)
> @@ -722,8 +729,8 @@ gen7_blorp_emit_depth_stencil_config(struct brw_context *brw,
>        surfwidth = params->depth.width;
>        surfheight = params->depth.height;
>     } else {
> -      surfwidth = params->depth.mt->logical_width0;
> -      surfheight = params->depth.mt->logical_height0;
> +      surfwidth = ALIGN(params->depth.mt->logical_width0, 8);
> +      surfheight = ALIGN(params->depth.mt->logical_height0, 4);
>     }
>
>     /* 3DSTATE_DEPTH_BUFFER */
> @@ -863,10 +870,12 @@ gen7_blorp_exec(struct brw_context *brw,
>     uint32_t sampler_offset = 0;
>
>     uint32_t prog_offset = params->get_wm_prog(brw, &prog_data);
> -   gen6_emit_3dstate_multisample(brw, params->dst.num_samples);
> +   int num_samples = (params->hiz_op == GEN6_HIZ_OP_NONE) ?
> +      params->dst.num_samples : params->depth.mt->num_samples;
> +   gen6_emit_3dstate_multisample(brw, num_samples);
>     gen6_emit_3dstate_sample_mask(brw,
> -                                 params->dst.num_samples > 1 ?
> -                                 (1 << params->dst.num_samples) - 1 : 1);
> +                                 num_samples > 1 ?
> +                                 (1 << num_samples) - 1 : 1);
>     gen6_blorp_emit_state_base_address(brw, params);
>     gen6_blorp_emit_vertices(brw, params);
>     gen7_blorp_emit_urb_config(brw, params);
> @@ -908,8 +917,8 @@ gen7_blorp_exec(struct brw_context *brw,
>     gen7_blorp_emit_gs_disable(brw, params);
>     gen7_blorp_emit_streamout_disable(brw, params);
>     gen6_blorp_emit_clip_disable(brw, params);
> -   gen7_blorp_emit_sf_config(brw, params);
> -   gen7_blorp_emit_wm_config(brw, params, prog_data);
> +   gen7_blorp_emit_sf_config(brw, params, num_samples);
> +   gen7_blorp_emit_wm_config(brw, params, prog_data, num_samples);
>     if (params->use_wm_prog) {
>        gen7_blorp_emit_binding_table_pointers_ps(brw, params,
>                                                  wm_bind_bo_offset);
> @@ -918,7 +927,7 @@ gen7_blorp_exec(struct brw_context *brw,
>     } else {
>        gen7_blorp_emit_constant_ps_disable(brw, params);
>     }
> -   gen7_blorp_emit_ps_config(brw, params, prog_offset, prog_data);
> +   gen7_blorp_emit_ps_config(brw, params, prog_offset, prog_data, num_samples);
>     gen7_blorp_emit_cc_viewport(brw, params);
>
>     if (params->depth.mt)
> --
> 1.8.5.3
>


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