[Intel-gfx] [PATCH v13 19/21] drm/i915/guc: Fix enable/disable of GuC GGTT invalidate functions

[Michal Wajdeczko]

On Wed, 11 Oct 2017 10:54:14 +0200, Sagar Arun Kamble  
<sagar.a.kamble at intel.com> wrote:

> i915_ggtt_enable_guc has to happen first during i915_gem_resume
> if GuC loading is enabled before GTT restore. In case GuC is not
> loaded this enabling happening during intel_uc_init_hw need to
> skipped. (avoid the GEM_BUG_ON)
> i915_ggtt_disable_guc at the end of reset/suspend/unload is needed
> post GGTT suspend operations. Calling it during uc_sanitize covers
> all scenarios. Hence, it is removed from intel_uc_fini_hw. Also these
> needto be protected by struct_mutex. Hence struct_mutex locking is
> added in i915_gem_sanitize while sanitizing uC. struct_mutex is already
> held during i915_gem_reset_prepare.
>
> Signed-off-by: Sagar Arun Kamble <sagar.a.kamble at intel.com>
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Michał Winiarski <michal.winiarski at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/i915_gem.c |  4 ++++
>  drivers/gpu/drm/i915/intel_uc.c | 16 +++++++++++-----
>  2 files changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem.c  
> b/drivers/gpu/drm/i915/i915_gem.c
> index a4bbf6c..77a0746 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -4759,6 +4759,10 @@ void i915_gem_resume(struct drm_i915_private  
> *dev_priv)
>  	WARN_ON(dev_priv->gt.awake);
> 	mutex_lock(&dev->struct_mutex);
> +	/* We need to notify the guc whenever we change the GGTT */
> +	if (i915_modparams.enable_guc_loading)
> +		i915_ggtt_enable_guc(dev_priv);
> +
>  	i915_gem_restore_gtt_mappings(dev_priv);
>  	i915_gem_restore_fences(dev_priv);
> diff --git a/drivers/gpu/drm/i915/intel_uc.c  
> b/drivers/gpu/drm/i915/intel_uc.c
> index 9010ab5..0b799fe 100644
> --- a/drivers/gpu/drm/i915/intel_uc.c
> +++ b/drivers/gpu/drm/i915/intel_uc.c
> @@ -184,8 +184,14 @@ int intel_uc_init_hw(struct drm_i915_private  
> *dev_priv)
>  	guc_disable_communication(guc);
>  	gen9_reset_guc_interrupts(dev_priv);
> -	/* We need to notify the guc whenever we change the GGTT */
> -	i915_ggtt_enable_guc(dev_priv);
> +	/*
> +	 * We need to notify the guc whenever we change the GGTT.
> +	 * During resume from sleep we would have already updated the
> +	 * GGTT invalidate function for GuC during i915_gem_resume so
> +	 * we need to skip here. Will enable here on driver load/reset.
> +	 */
> +	if (!guc->suspended)
> +		i915_ggtt_enable_guc(dev_priv);
> 	if (i915_modparams.enable_guc_submission) {
>  		/*
> @@ -309,9 +315,6 @@ void intel_uc_cleanup(struct drm_i915_private  
> *dev_priv)
>  	guc_free_load_err_log(guc);
> 	i915_guc_submission_cleanup(dev_priv);
> -
> -	if (i915_modparams.enable_guc_loading)
> -		i915_ggtt_disable_guc(dev_priv);
>  }
> /**
> @@ -452,6 +455,9 @@ void intel_uc_sanitize(struct drm_i915_private  
> *dev_priv)
>  	struct intel_uc_fw *huc_fw = &dev_priv->huc.fw;
> 	if (i915_modparams.enable_guc_loading) {
> +		if (guc_fw->load_status == INTEL_UC_FIRMWARE_SUCCESS)

Hmm, isn't that check redundant ?

> +			i915_ggtt_disable_guc(dev_priv);
> +
>  		guc_fw->load_status = INTEL_UC_FIRMWARE_NONE;
>  		huc_fw->load_status = INTEL_UC_FIRMWARE_NONE;
>  	}

Btw, what should we do with "suspended" flag during sanitize ?