[Intel-gfx] [RFC PATCH 103/162] drm/i915: allocate context from LMEM

[Chris Wilson]

Quoting Matthew Auld (2020-11-27 12:06:19)
> Based on a patch from Michel Thierry.
> 
> Signed-off-by: Matthew Auld <matthew.auld at intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> Cc: Abdiel Janulgue <abdiel.janulgue at linux.intel.com>
> ---
>  .../drm/i915/gt/intel_execlists_submission.c  | 31 ++++++++++++++++++-
>  1 file changed, 30 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> index 582a9044727e..c640b90711fd 100644
> --- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> @@ -108,6 +108,8 @@
>   */
>  #include <linux/interrupt.h>
>  
> +#include "gem/i915_gem_lmem.h"
> +
>  #include "i915_drv.h"
>  #include "i915_perf.h"
>  #include "i915_trace.h"
> @@ -4660,6 +4662,21 @@ static struct intel_timeline *pinned_timeline(struct intel_context *ce)
>                                                  page_unmask_bits(tl));
>  }
>  
> +static int context_clear_lmem(struct drm_i915_gem_object *ctx_obj)
> +{
> +       void *vaddr;
> +
> +       vaddr = i915_gem_object_pin_map(ctx_obj, I915_MAP_WC);
> +       if (IS_ERR(vaddr))
> +               return PTR_ERR(vaddr);
> +
> +       memset64(vaddr, 0, ctx_obj->base.size / sizeof(u64));
> +
> +       i915_gem_object_unpin_map(ctx_obj);

What? We copy over the entire object with the default state.
-Chris