drm/radeon/kms/pm: add support for SetVoltage cmd table (V2)

- This enables voltage adjustment on r6xx+ and certain
r5xx asics.
- Voltage drop support is already available for most
r1xx-r5xx asics.

V2: endian fix for voltage table.

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index 79887ca..7bb4c3e 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -74,7 +74,8 @@
 			if (voltage->delay)
 				udelay(voltage->delay);
 		}
-	}
+	} else if (voltage->type == VOLTAGE_VDDC)
+		radeon_atom_set_voltage(rdev, voltage->vddc_id);
 
 	dyn_pwrmgt_sclk_length = RREG32_PLL(DYN_PWRMGT_SCLK_LENGTH);
 	dyn_pwrmgt_sclk_length &= ~REDUCED_POWER_SCLK_HILEN(0xf);