Commit 655bd3b9 authored by Ashutosh Dixit's avatar Ashutosh Dixit Committed by Rodrigo Vivi
Browse files

drm/i915/hwmon: Block waiting for GuC reset to complete 



Instead of erroring out when GuC reset is in progress, block waiting for
GuC reset to complete which is a more reasonable uapi behavior.

v2: Avoid race between wake_up_all and waiting for wakeup (Rodrigo)
v3: Remove timeout when blocked (Tvrtko)

Signed-off-by: default avatarAshutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230420164041.1428455-4-ashutosh.dixit@intel.com
parent 1b44019a

drivers/gpu/drm/i915/i915_hwmon.c

+25 −4
Original line number Diff line number Diff line
@@ -51,6 +51,7 @@ struct hwm_drvdata { 
	char name[12];

	int gt_n;

	bool reset_in_progress;

	wait_queue_head_t waitq;

};



struct i915_hwmon {
@@ -397,14 +398,32 @@ hwm_power_max_write(struct hwm_drvdata *ddat, long val) 
{

	struct i915_hwmon *hwmon = ddat->hwmon;

	intel_wakeref_t wakeref;

	DEFINE_WAIT(wait);

	int ret = 0;

	u32 nval;



	/* Block waiting for GuC reset to complete when needed */

	for (;;) {

		mutex_lock(&hwmon->hwmon_lock);

	if (hwmon->ddat.reset_in_progress) {

		ret = -EAGAIN;

		goto unlock;



		prepare_to_wait(&ddat->waitq, &wait, TASK_INTERRUPTIBLE);



		if (!hwmon->ddat.reset_in_progress)

			break;



		if (signal_pending(current)) {

			ret = -EINTR;

			break;

		}



		mutex_unlock(&hwmon->hwmon_lock);



		schedule();

	}

	finish_wait(&ddat->waitq, &wait);

	if (ret)

		goto unlock;



	wakeref = intel_runtime_pm_get(ddat->uncore->rpm);



	/* Disable PL1 limit and verify, because the limit cannot be disabled on all platforms */
@@ -508,6 +527,7 @@ void i915_hwmon_power_max_restore(struct drm_i915_private *i915, bool old) 
	intel_uncore_rmw(hwmon->ddat.uncore, hwmon->rg.pkg_rapl_limit,

			 PKG_PWR_LIM_1_EN, old ? PKG_PWR_LIM_1_EN : 0);

	hwmon->ddat.reset_in_progress = false;

	wake_up_all(&hwmon->ddat.waitq);



	mutex_unlock(&hwmon->hwmon_lock);

}
@@ -784,6 +804,7 @@ void i915_hwmon_register(struct drm_i915_private *i915) 
	ddat->uncore = &i915->uncore;

	snprintf(ddat->name, sizeof(ddat->name), "i915");

	ddat->gt_n = -1;

	init_waitqueue_head(&ddat->waitq);



	for_each_gt(gt, i915, i) {

		ddat_gt = hwmon->ddat_gt + i;