drm/radeon/dpm: implement vblank_too_short callback for cayman

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>

diff --git a/drivers/gpu/drm/radeon/ni_dpm.c b/drivers/gpu/drm/radeon/ni_dpm.c
index bd96eaa..559cf24 100644 (file)
--- a/drivers/gpu/drm/radeon/ni_dpm.c
+++ b/drivers/gpu/drm/radeon/ni_dpm.c
@@ -765,6 +765,19 @@ static void ni_calculate_leakage_for_v_and_t(struct radeon_device *rdev,
        ni_calculate_leakage_for_v_and_t_formula(coeff, v, t, i_leakage, leakage);
 }
 
+bool ni_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;
+
+}
+
 static void ni_apply_state_adjust_rules(struct radeon_device *rdev,
                                        struct radeon_ps *rps)
 {
@@ -775,7 +788,8 @@ static void ni_apply_state_adjust_rules(struct radeon_device *rdev,
        u16 vddc, vddci;
        int i;
 
-       if (rdev->pm.dpm.new_active_crtc_count > 1)
+       if ((rdev->pm.dpm.new_active_crtc_count > 1) ||
+           ni_dpm_vblank_too_short(rdev))
                disable_mclk_switching = true;
        else
                disable_mclk_switching = false;

diff --git a/drivers/gpu/drm/radeon/radeon_asic.c b/drivers/gpu/drm/radeon/radeon_asic.c
index c42b367..c62428b 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_asic.c
+++ b/drivers/gpu/drm/radeon/radeon_asic.c
@@ -1945,6 +1945,7 @@ static struct radeon_asic cayman_asic = {
                .print_power_state = &ni_dpm_print_power_state,
                .debugfs_print_current_performance_level = &ni_dpm_debugfs_print_current_performance_level,
                .force_performance_level = &ni_dpm_force_performance_level,
+               .vblank_too_short = &ni_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 bca9a8b..45d0693 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_asic.h
+++ b/drivers/gpu/drm/radeon/radeon_asic.h
@@ -624,6 +624,7 @@ void ni_dpm_debugfs_print_current_performance_level(struct radeon_device *rdev,
                                                    struct seq_file *m);
 int ni_dpm_force_performance_level(struct radeon_device *rdev,
                                   enum radeon_dpm_forced_level level);
+bool ni_dpm_vblank_too_short(struct radeon_device *rdev);
 int trinity_dpm_init(struct radeon_device *rdev);
 int trinity_dpm_enable(struct radeon_device *rdev);
 void trinity_dpm_disable(struct radeon_device *rdev);