drm/radeon/dpm: implement vblank_too_short callback for evergreen

Check if we can switch the mclk during the vblank time otherwise
we may get artifacts on the screen when the mclk changes.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

3 files changed, 15 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/cypress_dpm.c b/drivers/gpu/drm/radeon/cypress_dpm.c
index 9ef840807dd1..9bcdd174780f 100644
--- a/drivers/gpu/drm/radeon/cypress_dpm.c
+++ b/drivers/gpu/drm/radeon/cypress_dpm.c
@@ -2174,3 +2174,16 @@ void cypress_dpm_fini(struct radeon_device *rdev)
         kfree(rdev->pm.dpm.ps);
         kfree(rdev->pm.dpm.priv);
 }
+
+bool cypress_dpm_vblank_too_short(struct radeon_device *rdev)
+{
+        struct rv7xx_power_info *pi = rv770_get_pi(rdev);
+        u32 vblank_time = r600_dpm_get_vblank_time(rdev);
+        u32 switch_limit = pi->mem_gddr5 ? 450 : 300;
+
+        if (vblank_time < switch_limit)
+                return true;
+        else
+                return false;
+
+}
diff --git a/drivers/gpu/drm/radeon/radeon_asic.c b/drivers/gpu/drm/radeon/radeon_asic.c
index c3b2f9605f6d..e73026393a46 100644
--- a/drivers/gpu/drm/radeon/radeon_asic.c
+++ b/drivers/gpu/drm/radeon/radeon_asic.c
@@ -1519,6 +1519,7 @@ static struct radeon_asic evergreen_asic = {
                 .print_power_state = &rv770_dpm_print_power_state,
                 .debugfs_print_current_performance_level = &rv770_dpm_debugfs_print_current_performance_level,
                 .force_performance_level = &rv770_dpm_force_performance_level,
+                .vblank_too_short = &cypress_dpm_vblank_too_short,
         },
         .pflip = {
                 .pre_page_flip = &evergreen_pre_page_flip,
diff --git a/drivers/gpu/drm/radeon/radeon_asic.h b/drivers/gpu/drm/radeon/radeon_asic.h
index ca219e9fc2b4..0ef8b4967b9c 100644
--- a/drivers/gpu/drm/radeon/radeon_asic.h
+++ b/drivers/gpu/drm/radeon/radeon_asic.h
@@ -545,6 +545,7 @@ void cypress_dpm_disable(struct radeon_device *rdev);
 int cypress_dpm_set_power_state(struct radeon_device *rdev);
 void cypress_dpm_display_configuration_changed(struct radeon_device *rdev);
 void cypress_dpm_fini(struct radeon_device *rdev);
+bool cypress_dpm_vblank_too_short(struct radeon_device *rdev);
 int btc_dpm_init(struct radeon_device *rdev);
 void btc_dpm_setup_asic(struct radeon_device *rdev);
 int btc_dpm_enable(struct radeon_device *rdev);