Commit 292e4fb0 authored by Vinay Belgaumkar's avatar Vinay Belgaumkar Committed by John Harrison
Browse files

drm/i915/guc/slpc: Define and initialize boost frequency 



Define helpers and struct members required to record boost info.
Boost frequency is initialized to RP0 at SLPC init. Also define num_waiters
which can track the pending boost requests.

Boost will be done by scheduling a worker thread. This will avoid
the need to make H2G calls inside an interrupt context. Initialize the
worker function during SLPC init as well. Had to move intel_guc_slpc_init
a few lines below to accommodate this.

v2: Add a workqueue to handle waitboost
v3: Code review comments (Ashutosh)

Cc: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: default avatarVinay Belgaumkar <vinay.belgaumkar@intel.com>
Reviewed-by: default avatarAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: default avatarJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211102012608.8609-2-vinay.belgaumkar@intel.com
parent c1f110ee

drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c

+79 −23
Original line number Diff line number Diff line
@@ -79,29 +79,6 @@ static void slpc_mem_set_disabled(struct slpc_shared_data *data, 
	slpc_mem_set_param(data, enable_id, 0);

}



int intel_guc_slpc_init(struct intel_guc_slpc *slpc)

{

	struct intel_guc *guc = slpc_to_guc(slpc);

	struct drm_i915_private *i915 = slpc_to_i915(slpc);

	u32 size = PAGE_ALIGN(sizeof(struct slpc_shared_data));

	int err;



	GEM_BUG_ON(slpc->vma);



	err = intel_guc_allocate_and_map_vma(guc, size, &slpc->vma, (void **)&slpc->vaddr);

	if (unlikely(err)) {

		drm_err(&i915->drm,

			"Failed to allocate SLPC struct (err=%pe)\n",

			ERR_PTR(err));

		return err;

	}



	slpc->max_freq_softlimit = 0;

	slpc->min_freq_softlimit = 0;



	return err;

}



static u32 slpc_get_state(struct intel_guc_slpc *slpc)

{

	struct slpc_shared_data *data;
@@ -203,6 +180,82 @@ static int slpc_unset_param(struct intel_guc_slpc *slpc, 
	return guc_action_slpc_unset_param(guc, id);

}



static int slpc_force_min_freq(struct intel_guc_slpc *slpc, u32 freq)

{

	struct drm_i915_private *i915 = slpc_to_i915(slpc);

	intel_wakeref_t wakeref;

	int ret = 0;



	lockdep_assert_held(&slpc->lock);



	/*

	 * This function is a little different as compared to

	 * intel_guc_slpc_set_min_freq(). Softlimit will not be updated

	 * here since this is used to temporarily change min freq,

	 * for example, during a waitboost. Caller is responsible for

	 * checking bounds.

	 */



	with_intel_runtime_pm(&i915->runtime_pm, wakeref) {

		ret = slpc_set_param(slpc,

				     SLPC_PARAM_GLOBAL_MIN_GT_UNSLICE_FREQ_MHZ,

				     freq);

		if (ret)

			drm_err(&i915->drm, "Unable to force min freq to %u: %d",

				freq, ret);

	}



	return ret;

}



static void slpc_boost_work(struct work_struct *work)

{

	struct intel_guc_slpc *slpc = container_of(work, typeof(*slpc), boost_work);



	/*

	 * Raise min freq to boost. It's possible that

	 * this is greater than current max. But it will

	 * certainly be limited by RP0. An error setting

	 * the min param is not fatal.

	 */

	mutex_lock(&slpc->lock);

	if (atomic_read(&slpc->num_waiters)) {

		slpc_force_min_freq(slpc, slpc->boost_freq);

		slpc->num_boosts++;

	}

	mutex_unlock(&slpc->lock);

}



int intel_guc_slpc_init(struct intel_guc_slpc *slpc)

{

	struct intel_guc *guc = slpc_to_guc(slpc);

	struct drm_i915_private *i915 = slpc_to_i915(slpc);

	u32 size = PAGE_ALIGN(sizeof(struct slpc_shared_data));

	int err;



	GEM_BUG_ON(slpc->vma);



	err = intel_guc_allocate_and_map_vma(guc, size, &slpc->vma, (void **)&slpc->vaddr);

	if (unlikely(err)) {

		drm_err(&i915->drm,

			"Failed to allocate SLPC struct (err=%pe)\n",

			ERR_PTR(err));

		return err;

	}



	slpc->max_freq_softlimit = 0;

	slpc->min_freq_softlimit = 0;



	slpc->boost_freq = 0;

	atomic_set(&slpc->num_waiters, 0);

	slpc->num_boosts = 0;



	mutex_init(&slpc->lock);

	INIT_WORK(&slpc->boost_work, slpc_boost_work);



	return err;

}



static const char *slpc_global_state_to_string(enum slpc_global_state state)

{

	switch (state) {
@@ -522,6 +575,9 @@ static void slpc_get_rp_values(struct intel_guc_slpc *slpc) 
					GT_FREQUENCY_MULTIPLIER;

	slpc->min_freq = REG_FIELD_GET(RPN_CAP_MASK, rp_state_cap) *

					GT_FREQUENCY_MULTIPLIER;



	if (!slpc->boost_freq)

		slpc->boost_freq = slpc->rp0_freq;

}



/*

drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h

+1 −0
Original line number Diff line number Diff line
@@ -38,5 +38,6 @@ 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);

int intel_guc_slpc_print_info(struct intel_guc_slpc *slpc, struct drm_printer *p);

void intel_guc_pm_intrmsk_enable(struct intel_gt *gt);

void intel_guc_slpc_boost(struct intel_guc_slpc *slpc);



#endif

drivers/gpu/drm/i915/gt/uc/intel_guc_slpc_types.h

+13 −0
Original line number Diff line number Diff line
@@ -6,6 +6,9 @@ 
#ifndef _INTEL_GUC_SLPC_TYPES_H_

#define _INTEL_GUC_SLPC_TYPES_H_



#include <linux/atomic.h>

#include <linux/workqueue.h>

#include <linux/mutex.h>

#include <linux/types.h>



#define SLPC_RESET_TIMEOUT_MS 5
@@ -20,10 +23,20 @@ struct intel_guc_slpc { 
	u32 min_freq;

	u32 rp0_freq;

	u32 rp1_freq;

	u32 boost_freq;



	/* frequency softlimits */

	u32 min_freq_softlimit;

	u32 max_freq_softlimit;



	/* Protects set/reset of boost freq

	 * and value of num_waiters

	 */

	struct mutex lock;



	struct work_struct boost_work;

	atomic_t num_waiters;

	u32 num_boosts;

};



#endif