Re: [Intel-xe] [PATCH v4] drm/xe: remove gucrc disable from suspend path

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Mon, Jul 17, 2023 at 03:29:00PM +0530, Riana Tauro wrote:
> Currently GuCRC is disabled in suspend path for xe.
> Rc6 is a prerequiste to enable s0ix and
> should not be disabled for s2idle. There is no requirement
> to disable GuCRC for S3+.
> 
> Remove it from xe_guc_pc_stop, thus removing from suspend path.
> Retain the call in other places where xe_guc_pc_stop is
> called.
> 
> v2: add description and return statement to kernel-doc (Rodrigo)
> v3: update commit message (Rodrigo)
> v4: add mem_access_get to the gucrc disable function

it looks safer now. pushed. Thanks

> 
> Signed-off-by: Riana Tauro <riana.tauro@intel.com>
> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_gt.c     |  1 +
>  drivers/gpu/drm/xe/xe_guc_pc.c | 20 +++++++++++++-------
>  drivers/gpu/drm/xe/xe_guc_pc.h |  1 +
>  drivers/gpu/drm/xe/xe_uc.c     |  5 +++++
>  drivers/gpu/drm/xe/xe_uc.h     |  1 +
>  5 files changed, 21 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_gt.c b/drivers/gpu/drm/xe/xe_gt.c
> index a21d44bfe9e8..b31ef2a8ff17 100644
> --- a/drivers/gpu/drm/xe/xe_gt.c
> +++ b/drivers/gpu/drm/xe/xe_gt.c
> @@ -517,6 +517,7 @@ static int gt_reset(struct xe_gt *gt)
>  	if (err)
>  		goto err_msg;
>  
> +	xe_uc_gucrc_disable(&gt->uc);
>  	xe_uc_stop_prepare(&gt->uc);
>  	xe_gt_pagefault_reset(gt);
>  
> diff --git a/drivers/gpu/drm/xe/xe_guc_pc.c b/drivers/gpu/drm/xe/xe_guc_pc.c
> index 3093cfeff0c2..03dfbde29fe5 100644
> --- a/drivers/gpu/drm/xe/xe_guc_pc.c
> +++ b/drivers/gpu/drm/xe/xe_guc_pc.c
> @@ -730,12 +730,20 @@ static int pc_adjust_requested_freq(struct xe_guc_pc *pc)
>  	return ret;
>  }
>  
> -static int pc_gucrc_disable(struct xe_guc_pc *pc)
> +/**
> + * xe_guc_pc_gucrc_disable - Disable GuC RC
> + * @pc: Xe_GuC_PC instance
> + *
> + * Disables GuC RC by taking control of RC6 back from GuC.
> + *
> + * Return: 0 on success, negative error code on error.
> + */
> +int xe_guc_pc_gucrc_disable(struct xe_guc_pc *pc)
>  {
>  	struct xe_gt *gt = pc_to_gt(pc);
>  	int ret;
>  
> -	xe_device_assert_mem_access(pc_to_xe(pc));
> +	xe_device_mem_access_get(pc_to_xe(pc));
>  
>  	ret = pc_action_setup_gucrc(pc, XE_GUCRC_HOST_CONTROL);
>  	if (ret)
> @@ -750,6 +758,7 @@ static int pc_gucrc_disable(struct xe_guc_pc *pc)
>  	xe_mmio_write32(gt, RC_STATE, 0);
>  
>  	XE_WARN_ON(xe_force_wake_put(gt_to_fw(gt), XE_FORCEWAKE_ALL));
> +	xe_device_mem_access_put(pc_to_xe(pc));
>  	return 0;
>  }
>  
> @@ -827,7 +836,7 @@ int xe_guc_pc_start(struct xe_guc_pc *pc)
>  		goto out;
>  
>  	if (xe->info.platform == XE_PVC) {
> -		pc_gucrc_disable(pc);
> +		xe_guc_pc_gucrc_disable(pc);
>  		ret = 0;
>  		goto out;
>  	}
> @@ -850,10 +859,6 @@ int xe_guc_pc_stop(struct xe_guc_pc *pc)
>  
>  	xe_device_mem_access_get(pc_to_xe(pc));
>  
> -	ret = pc_gucrc_disable(pc);
> -	if (ret)
> -		goto out;
> -
>  	mutex_lock(&pc->freq_lock);
>  	pc->freq_ready = false;
>  	mutex_unlock(&pc->freq_lock);
> @@ -876,6 +881,7 @@ static void pc_fini(struct drm_device *drm, void *arg)
>  {
>  	struct xe_guc_pc *pc = arg;
>  
> +	XE_WARN_ON(xe_guc_pc_gucrc_disable(pc));
>  	XE_WARN_ON(xe_guc_pc_stop(pc));
>  	sysfs_remove_files(pc_to_gt(pc)->sysfs, pc_attrs);
>  	xe_bo_unpin_map_no_vm(pc->bo);
> diff --git a/drivers/gpu/drm/xe/xe_guc_pc.h b/drivers/gpu/drm/xe/xe_guc_pc.h
> index 370353a40a17..81833a53b3c9 100644
> --- a/drivers/gpu/drm/xe/xe_guc_pc.h
> +++ b/drivers/gpu/drm/xe/xe_guc_pc.h
> @@ -11,6 +11,7 @@
>  int xe_guc_pc_init(struct xe_guc_pc *pc);
>  int xe_guc_pc_start(struct xe_guc_pc *pc);
>  int xe_guc_pc_stop(struct xe_guc_pc *pc);
> +int xe_guc_pc_gucrc_disable(struct xe_guc_pc *pc);
>  
>  enum xe_gt_idle_state xe_guc_pc_c_status(struct xe_guc_pc *pc);
>  u64 xe_guc_pc_rc6_residency(struct xe_guc_pc *pc);
> diff --git a/drivers/gpu/drm/xe/xe_uc.c b/drivers/gpu/drm/xe/xe_uc.c
> index 70eabf567156..f8cbd292d6d0 100644
> --- a/drivers/gpu/drm/xe/xe_uc.c
> +++ b/drivers/gpu/drm/xe/xe_uc.c
> @@ -176,6 +176,11 @@ int xe_uc_reset_prepare(struct xe_uc *uc)
>  	return xe_guc_reset_prepare(&uc->guc);
>  }
>  
> +void xe_uc_gucrc_disable(struct xe_uc *uc)
> +{
> +	XE_WARN_ON(xe_guc_pc_gucrc_disable(&uc->guc.pc));
> +}
> +
>  void xe_uc_stop_prepare(struct xe_uc *uc)
>  {
>  	xe_guc_stop_prepare(&uc->guc);
> diff --git a/drivers/gpu/drm/xe/xe_uc.h b/drivers/gpu/drm/xe/xe_uc.h
> index d6efc9ef00d3..42219b361df5 100644
> --- a/drivers/gpu/drm/xe/xe_uc.h
> +++ b/drivers/gpu/drm/xe/xe_uc.h
> @@ -12,6 +12,7 @@ int xe_uc_init(struct xe_uc *uc);
>  int xe_uc_init_hwconfig(struct xe_uc *uc);
>  int xe_uc_init_post_hwconfig(struct xe_uc *uc);
>  int xe_uc_init_hw(struct xe_uc *uc);
> +void xe_uc_gucrc_disable(struct xe_uc *uc);
>  int xe_uc_reset_prepare(struct xe_uc *uc);
>  void xe_uc_stop_prepare(struct xe_uc *uc);
>  int xe_uc_stop(struct xe_uc *uc);
> -- 
> 2.40.0
>