drm/radeon: replace vmram_mutex with mclk_lock v2

It is a rw_semaphore now and only write locked
while changing the clock. Also the lock is renamed
to better reflect what it is protecting.

v2: Keep the ttm_vm_ops on IGPs
Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>

drivers/gpu/drm/radeon/radeon.h

@@ -1059,6 +1059,8 @@ struct radeon_power_state {
 
 struct radeon_pm {
 	struct mutex		mutex;
+	/* write locked while reprogramming mclk */
+	struct rw_semaphore	mclk_lock;
 	u32			active_crtcs;
 	int			active_crtc_count;
 	int			req_vblank;
@@ -1554,7 +1556,6 @@ struct radeon_device {
 	struct work_struct audio_work;
 	int num_crtc; /* number of crtcs */
 	struct mutex dc_hw_i2c_mutex; /* display controller hw i2c mutex */
-	struct mutex vram_mutex;
 	bool audio_enabled;
 	struct r600_audio audio_status; /* audio stuff */
 	struct notifier_block acpi_nb;

drivers/gpu/drm/radeon/radeon_device.c

@@ -735,7 +735,7 @@ int radeon_device_init(struct radeon_device *rdev,
 		spin_lock_init(&rdev->ih.lock);
 	mutex_init(&rdev->gem.mutex);
 	mutex_init(&rdev->pm.mutex);
-	mutex_init(&rdev->vram_mutex);
+	init_rwsem(&rdev->pm.mclk_lock);
 	init_waitqueue_head(&rdev->irq.vblank_queue);
 	init_waitqueue_head(&rdev->irq.idle_queue);
 	r = radeon_gem_init(rdev);

drivers/gpu/drm/radeon/radeon_object.c

@@ -154,11 +154,11 @@ int radeon_bo_create(struct radeon_device *rdev,
 	INIT_LIST_HEAD(&bo->va);
 	radeon_ttm_placement_from_domain(bo, domain);
 	/* Kernel allocation are uninterruptible */
-	mutex_lock(&rdev->vram_mutex);
+	down_read(&rdev->pm.mclk_lock);
 	r = ttm_bo_init(&rdev->mman.bdev, &bo->tbo, size, type,
 			&bo->placement, page_align, 0, !kernel, NULL,
 			acc_size, sg, &radeon_ttm_bo_destroy);
-	mutex_unlock(&rdev->vram_mutex);
+	up_read(&rdev->pm.mclk_lock);
 	if (unlikely(r != 0)) {
 		if (r != -ERESTARTSYS) {
 			if (domain == RADEON_GEM_DOMAIN_VRAM) {
@@ -219,9 +219,9 @@ void radeon_bo_unref(struct radeon_bo **bo)
 		return;
 	rdev = (*bo)->rdev;
 	tbo = &((*bo)->tbo);
-	mutex_lock(&rdev->vram_mutex);
+	down_read(&rdev->pm.mclk_lock);
 	ttm_bo_unref(&tbo);
-	mutex_unlock(&rdev->vram_mutex);
+	up_read(&rdev->pm.mclk_lock);
 	if (tbo == NULL)
 		*bo = NULL;
 }

drivers/gpu/drm/radeon/radeon_pm.c

@@ -251,7 +251,7 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev)
 		return;
 
 	mutex_lock(&rdev->ddev->struct_mutex);
-	mutex_lock(&rdev->vram_mutex);
+	down_write(&rdev->pm.mclk_lock);
 	mutex_lock(&rdev->ring_lock);
 
 	/* gui idle int has issues on older chips it seems */
@@ -303,7 +303,7 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev)
 	rdev->pm.dynpm_planned_action = DYNPM_ACTION_NONE;
 
 	mutex_unlock(&rdev->ring_lock);
-	mutex_unlock(&rdev->vram_mutex);
+	up_write(&rdev->pm.mclk_lock);
 	mutex_unlock(&rdev->ddev->struct_mutex);
 }
 

drivers/gpu/drm/radeon/radeon_ttm.c

@@ -797,9 +797,9 @@ static int radeon_ttm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 		return VM_FAULT_NOPAGE;
 	}
 	rdev = radeon_get_rdev(bo->bdev);
-	mutex_lock(&rdev->vram_mutex);
+	down_read(&rdev->pm.mclk_lock);
 	r = ttm_vm_ops->fault(vma, vmf);
-	mutex_unlock(&rdev->vram_mutex);
+	up_read(&rdev->pm.mclk_lock);
 	return r;
 }