drm/amd/display: Set PSR level to enable ALPM by default

[Why & How]
While support ALPM, do ALPM state transition while PSR entry/exit.
ALPM is needed for PSR-SU feature, and since the function is ready,
we'd enable it by default.

- Add psr level definition to enable/disable ALPM and set ALPM
  powerdone mode.
- Enable ALPM by default
Signed-off-by: David Zhang <dingchen.zhang@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc_link.c

@@ -3364,6 +3364,10 @@ bool dc_link_setup_psr(struct dc_link *link,
 	 */
 	psr_context->psr_level.bits.DISABLE_PSR_ENTRY_ABORT = 1;
 
+	/* enable ALPM */
+	psr_context->psr_level.bits.DISABLE_ALPM = 0;
+	psr_context->psr_level.bits.ALPM_DEFAULT_PD_MODE = 1;
+
 	/* Controls additional delay after remote frame capture before
 	 * continuing power down, default = 0
 	 */

drivers/gpu/drm/amd/display/dc/dc_types.h

@@ -698,7 +698,9 @@ union dmcu_psr_level {
 		unsigned int SKIP_AUTO_STATE_ADVANCE:1;
 		unsigned int DISABLE_PSR_ENTRY_ABORT:1;
 		unsigned int SKIP_SINGLE_OTG_DISABLE:1;
-		unsigned int RESERVED:22;
+		unsigned int DISABLE_ALPM:1;
+		unsigned int ALPM_DEFAULT_PD_MODE:1;
+		unsigned int RESERVED:20;
 	} bits;
 	unsigned int u32all;
 };