[Intel-gfx] [PATCH 17/17] drm/i915/selftests: Exercise rc6 handling

[Andi Shyti]

Hi Chris,

On Tue, Nov 19, 2019 at 10:09:29AM +0000, Chris Wilson wrote:
> Reading from CTX_INFO upsets rc6, requiring us to detect and prevent
> possible rc6 context corruption. Poke at the bear!
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Imre Deak <imre.deak at intel.com>
> Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>

it looks good,

Reviewed-by: Andi Shyti <andi.shyti at intel.com>
Tested-by: Andi Shyti <andi.shyti at intel.com>

just a question, though

> diff --git a/drivers/gpu/drm/i915/gt/selftest_gt_pm.c b/drivers/gpu/drm/i915/gt/selftest_gt_pm.c
> index d1752f15702a..1d5bf93d1258 100644
> --- a/drivers/gpu/drm/i915/gt/selftest_gt_pm.c
> +++ b/drivers/gpu/drm/i915/gt/selftest_gt_pm.c
> @@ -6,6 +6,7 @@
>   */
>  
>  #include "selftest_llc.h"
> +#include "selftest_rc6.h"
>  
>  static int live_gt_resume(void *arg)
>  {
> @@ -58,3 +59,15 @@ int intel_gt_pm_live_selftests(struct drm_i915_private *i915)
>  
>  	return intel_gt_live_subtests(tests, &i915->gt);
>  }
> +
> +int intel_gt_pm_late_selftests(struct drm_i915_private *i915)
> +{
> +	static const struct i915_subtest tests[] = {
> +		SUBTEST(live_rc6_ctx),
> +	};
> +
> +	if (intel_gt_is_wedged(&i915->gt))
> +		return 0;
> +
> +	return intel_gt_live_subtests(tests, &i915->gt);
> +}

are you thinking of making this file a hub for all power
management selftests? wouldn't it be more neat if rc6, rps and
others have their own selftests declared independently,
considering that we might want to add more of them?

> +static const u32 *__live_rc6_ctx(struct intel_context *ce)
> +{
> +	struct i915_request *rq;
> +	u32 const *result;

'const' here? you like reckless life! :)

Andi