drm/amd/powerplay/smu7: add vblank check for mclk switching (v2)

Check to make sure the vblank period is long enough to support
mclk switching.

v2: drop needless initial assignment (Nils)

bug: https://bugs.freedesktop.org/show_bug.cgi?id=96868

Cc: stable@vger.kernel.org
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c b/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c
index a74a3db..1445c51 100644 (file)
--- a/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c
@@ -2655,6 +2655,28 @@ static int smu7_get_power_state_size(struct pp_hwmgr *hwmgr)
        return sizeof(struct smu7_power_state);
 }
 
+static int smu7_vblank_too_short(struct pp_hwmgr *hwmgr,
+                                uint32_t vblank_time_us)
+{
+       struct smu7_hwmgr *data = (struct smu7_hwmgr *)(hwmgr->backend);
+       uint32_t switch_limit_us;
+
+       switch (hwmgr->chip_id) {
+       case CHIP_POLARIS10:
+       case CHIP_POLARIS11:
+       case CHIP_POLARIS12:
+               switch_limit_us = data->is_memory_gddr5 ? 190 : 150;
+               break;
+       default:
+               switch_limit_us = data->is_memory_gddr5 ? 450 : 150;
+               break;
+       }
+
+       if (vblank_time_us < switch_limit_us)
+               return true;
+       else
+               return false;
+}
 
 static int smu7_apply_state_adjust_rules(struct pp_hwmgr *hwmgr,
                                struct pp_power_state *request_ps,
@@ -2669,6 +2691,7 @@ static int smu7_apply_state_adjust_rules(struct pp_hwmgr *hwmgr,
        bool disable_mclk_switching;
        bool disable_mclk_switching_for_frame_lock;
        struct cgs_display_info info = {0};
+       struct cgs_mode_info mode_info = {0};
        const struct phm_clock_and_voltage_limits *max_limits;
        uint32_t i;
        struct smu7_hwmgr *data = (struct smu7_hwmgr *)(hwmgr->backend);
@@ -2677,6 +2700,7 @@ static int smu7_apply_state_adjust_rules(struct pp_hwmgr *hwmgr,
        int32_t count;
        int32_t stable_pstate_sclk = 0, stable_pstate_mclk = 0;
 
+       info.mode_info = &mode_info;
        data->battery_state = (PP_StateUILabel_Battery ==
                        request_ps->classification.ui_label);
 
@@ -2703,8 +2727,6 @@ static int smu7_apply_state_adjust_rules(struct pp_hwmgr *hwmgr,
 
        cgs_get_active_displays_info(hwmgr->device, &info);
 
-       /*TO DO result = PHM_CheckVBlankTime(hwmgr, &vblankTooShort);*/
-
        minimum_clocks.engineClock = hwmgr->display_config.min_core_set_clock;
        minimum_clocks.memoryClock = hwmgr->display_config.min_mem_set_clock;
 
@@ -2769,8 +2791,9 @@ static int smu7_apply_state_adjust_rules(struct pp_hwmgr *hwmgr,
                                    PHM_PlatformCaps_DisableMclkSwitchingForFrameLock);
 
 
-       disable_mclk_switching = (1 < info.display_count) ||
-                                   disable_mclk_switching_for_frame_lock;
+       disable_mclk_switching = ((1 < info.display_count) ||
+                                 disable_mclk_switching_for_frame_lock ||
+                                 smu7_vblank_too_short(hwmgr, mode_info.vblank_time_us));
 
        sclk = smu7_ps->performance_levels[0].engine_clock;
        mclk = smu7_ps->performance_levels[0].memory_clock;