Re: [Intel-gfx] [PATCH 08/14] drm/i915/guc/slpc: Add get max/min freq hooks

Michal Wajdeczko
2021-07-21T18:00:19Z

On 21.07.2021 18:11, Vinay Belgaumkar wrote:
> Add helpers to read the min/max frequency being used
> by SLPC. This is done by send a H2G command which forces
> SLPC to update the shared data struct which can then be
> read.

add note that functions will be used later

>
> v2: Address review comments (Michal W)
>
> Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
> Signed-off-by: Sundaresan Sujaritha <sujaritha.sundaresan@intel.com>
> ---
> drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c | 52 +++++++++++++++++++++
> drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h | 2 +
> 2 files changed, 54 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
> index b40c39ba4049..c1cf8d46e360 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
> @@ -290,6 +290,32 @@ int intel_guc_slpc_set_max_freq(struct intel_guc_slpc *slpc, u32 val)
> return ret;
> }
>
> +/**
> + * intel_guc_slpc_get_max_freq() - Get max frequency limit for SLPC.
> + * @slpc: pointer to intel_guc_slpc.
> + * @val: pointer to val which will hold max frequency (MHz)
> + *
> + * This function will invoke GuC SLPC action to read the max frequency
> + * limit for unslice.
> + *
> + * Return: 0 on success, non-zero error code on failure.
> + */
> +int intel_guc_slpc_get_max_freq(struct intel_guc_slpc *slpc, u32 *val)
> +{
> + intel_wakeref_t wakeref;
> + struct drm_i915_private *i915 = guc_to_gt(slpc_to_guc(slpc))->i915;
> + int ret = 0;

struct drm_i915_private *i915 = slpc_to_i915(slpc);
intel_wakeref_t wakeref;
int ret = 0;

> +
> + with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
> + /* Force GuC to update task data */
> + slpc_query_task_state(slpc);

what if this call fails ?

> +
> + *val = slpc_decode_max_freq(slpc);
> + }
> +
> + return ret;
> +}
> +
> /**
> * intel_guc_slpc_set_min_freq() - Set min frequency limit for SLPC.
> * @slpc: pointer to intel_guc_slpc.
> @@ -322,6 +348,32 @@ int intel_guc_slpc_set_min_freq(struct intel_guc_slpc *slpc, u32 val)
> return ret;
> }
>
> +/**
> + * intel_guc_slpc_get_min_freq() - Get min frequency limit for SLPC.
> + * @slpc: pointer to intel_guc_slpc.
> + * @val: pointer to val which will hold min frequency (MHz)
> + *
> + * This function will invoke GuC SLPC action to read the min frequency
> + * limit for unslice.
> + *
> + * Return: 0 on success, non-zero error code on failure.
> + */
> +int intel_guc_slpc_get_min_freq(struct intel_guc_slpc *slpc, u32 *val)
> +{
> + intel_wakeref_t wakeref;
> + struct drm_i915_private *i915 = guc_to_gt(slpc_to_guc(slpc))->i915;
> + int ret = 0;
> +
> + with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
> + /* Force GuC to update task data */
> + slpc_query_task_state(slpc);

same here

Michal

> +
> + *val = slpc_decode_min_freq(slpc);
> + }
> +
> + return ret;
> +}
> +
> /*
> * intel_guc_slpc_enable() - Start SLPC
> * @slpc: pointer to intel_guc_slpc.
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h
> index 3a1a7eaafc12..627c71a95777 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h
> @@ -32,5 +32,7 @@ int intel_guc_slpc_enable(struct intel_guc_slpc *slpc);
> void intel_guc_slpc_fini(struct intel_guc_slpc *slpc);
> int intel_guc_slpc_set_max_freq(struct intel_guc_slpc *slpc, u32 val);
> int intel_guc_slpc_set_min_freq(struct intel_guc_slpc *slpc, u32 val);
> +int intel_guc_slpc_get_max_freq(struct intel_guc_slpc *slpc, u32 *val);
> +int intel_guc_slpc_get_min_freq(struct intel_guc_slpc *slpc, u32 *val);
>
> #endif
>