[Intel-gfx] [PATCH 2/2] drm/i915: kill resource streamer

[Chris Wilson]

Quoting Lucas De Marchi (2018-07-10 01:06:58)
> diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> index 1932bc227942..a5eec97a40fe 100644
> --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> @@ -2221,19 +2221,8 @@ i915_gem_do_execbuffer(struct drm_device *dev,
>         if (!eb.engine)
>                 return -EINVAL;
>  
> -       if (args->flags & I915_EXEC_RESOURCE_STREAMER) {
> -               if (!HAS_RESOURCE_STREAMER(eb.i915)) {
> -                       DRM_DEBUG("RS is only allowed for Haswell and Gen8 - Gen10\n");
> -                       return -EINVAL;
> -               }
> -               if (eb.engine->id != RCS) {
> -                       DRM_DEBUG("RS is not available on %s\n",
> -                                eb.engine->name);
> -                       return -EINVAL;
> -               }
> -
> -               eb.batch_flags |= I915_DISPATCH_RS;
> -       }
> +       if (args->flags & I915_EXEC_RESOURCE_STREAMER)
> +               DRM_DEBUG("RS is removed from all Gens: ignoring.\n");

return -EINVAL;

If userspace set up its batch on the assumption that RS is enabled, it
will fail.

> @@ -2657,10 +2656,7 @@ static void execlists_init_reg_state(u32 *regs,
>  
>         CTX_REG(regs, CTX_CONTEXT_CONTROL, RING_CONTEXT_CONTROL(engine),
>                 _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT |
> -                                   CTX_CTRL_ENGINE_CTX_SAVE_INHIBIT) |
> -               _MASKED_BIT_ENABLE(CTX_CTRL_INHIBIT_SYN_CTX_SWITCH |

Bring back INHIBIT_SYNC_CTX_SWITCH.

> diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
> index 7f5634ce8e88..179e0477dbc6 100644
> --- a/include/uapi/drm/i915_drm.h
> +++ b/include/uapi/drm/i915_drm.h
> @@ -449,6 +449,7 @@ typedef struct drm_i915_irq_wait {
>  #define I915_PARAM_SUBSLICE_TOTAL       33
>  #define I915_PARAM_EU_TOTAL             34
>  #define I915_PARAM_HAS_GPU_RESET        35
> +/* Deprecated: do not use */

Don't bother. As written it implies all subsequent param are deprecated.
Userspace knows simply by the query return.

>  #define I915_PARAM_HAS_RESOURCE_STREAMER 36
>  #define I915_PARAM_HAS_EXEC_SOFTPIN     37
>  #define I915_PARAM_HAS_POOLED_EU        38