[Intel-gfx] [PATCH 21/67] drm/i915/cnl: Update the context size

[Daniele Ceraolo Spurio]

On 06/04/17 12:15, Rodrigo Vivi wrote:
> From: Ben Widawsky <benjamin.widawsky at intel.com>
>
> The docs are not yet correct, so I cannot provide a reference to it. In the
> current docs, the size is actually smaller than SKL. This seems unlikely given
> that in another part of the docs there are clearly more engines stored within
> the context image.
>
> !UPSTREAM: I got this number from the Windows driver, but we should add the right
> reference to the docs when we have it..
>
> v2: (Rodrigo) Fixup the missing break identified by Tvrtko.
>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Signed-off-by: Ben Widawsky <benjamin.widawsky at intel.com>
> Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_lrc.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index 23e2bed..058d5f2 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -138,6 +138,7 @@
>  #include "i915_drv.h"
>  #include "intel_mocs.h"
>
> +#define GEN10_LR_CONTEXT_RENDER_SIZE ((1 + 33) * PAGE_SIZE)

1+33 looks really big compared to what's in the specs. I agree that the 
specs are unclear, but something around 1+18 should still be a safe 
setting. Unfortunately I don't have a setup to verify, so I'm happy to 
merge this as it is as long as we remember to come and re-assess it 
(maybe add a TODO?)

Thanks,
Daniele

>  #define GEN9_LR_CONTEXT_RENDER_SIZE (22 * PAGE_SIZE)
>  #define GEN8_LR_CONTEXT_RENDER_SIZE (20 * PAGE_SIZE)
>  #define GEN8_LR_CONTEXT_OTHER_SIZE (2 * PAGE_SIZE)
> @@ -1930,10 +1931,19 @@ uint32_t intel_lr_context_size(struct intel_engine_cs *engine)
>
>  	switch (engine->id) {
>  	case RCS:
> -		if (INTEL_GEN(engine->i915) >= 9)
> +		switch (INTEL_GEN(engine->i915)) {
> +		default:
> +			DRM_ERROR("Unknown context size for GEN\n");
> +		case 10:
> +			ret = GEN10_LR_CONTEXT_RENDER_SIZE;
> +			break;
> +		case 9:
>  			ret = GEN9_LR_CONTEXT_RENDER_SIZE;
> -		else
> +			break;
> +		case 8:
>  			ret = GEN8_LR_CONTEXT_RENDER_SIZE;
> +			break;
> +		}
>  		break;
>  	case VCS:
>  	case BCS:
>