drm/radeon/dpm: fixup dynamic state adjust for btc (v2)

Use a dedicated copy of the current power state since
we may have to adjust it on the fly.

v2: fix up redundant state sets

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/rv770_dpm.c b/drivers/gpu/drm/radeon/rv770_dpm.c
index 75062c4..d3a55b7 100644
--- a/drivers/gpu/drm/radeon/rv770_dpm.c
+++ b/drivers/gpu/drm/radeon/rv770_dpm.c
@@ -2177,6 +2177,16 @@
 		pl->vddc = vddc;
 		pl->vddci = vddci;
 	}
+
+	if (rdev->family >= CHIP_BARTS) {
+		if ((rps->class & ATOM_PPLIB_CLASSIFICATION_UI_MASK) ==
+		    ATOM_PPLIB_CLASSIFICATION_UI_PERFORMANCE) {
+			rdev->pm.dpm.dyn_state.max_clock_voltage_on_ac.sclk = pl->sclk;
+			rdev->pm.dpm.dyn_state.max_clock_voltage_on_ac.mclk = pl->mclk;
+			rdev->pm.dpm.dyn_state.max_clock_voltage_on_ac.vddc = pl->vddc;
+			rdev->pm.dpm.dyn_state.max_clock_voltage_on_ac.vddci = pl->vddci;
+		}
+	}
 }
 
 int rv7xx_parse_power_table(struct radeon_device *rdev)