drm/amd/display: Add BLNDGAM memory shutdown support

[Why]
The BLNDGAM memory blocks should be powered down when they're not in
use. This will reduce power consumption.

[How]
1. Write to BLNDGAM_MEM_PWR_FORCE to put memory to shutdown when BLNDGAM
is not used.
2. Added a debug option to allow this behaviour to be turned off

Signed-off-by: Jacky Liao <[e-mail]>
Reviewed-by: Eric Yang <[e-mail]>
Acked-by: Rodrigo Siqueira <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/display/dc/dcn30/dcn30_dpp.c

···
 {
 	struct dcn3_dpp *dpp = TO_DCN30_DPP(dpp_base);
 
-	REG_SET(CM_MEM_PWR_CTRL, 0,
-			BLNDGAM_MEM_PWR_FORCE, power_on == true ? 0:1);
-
+	if (dpp_base->ctx->dc->debug.enable_mem_low_power.bits.cm) {
+		REG_UPDATE(CM_MEM_PWR_CTRL, BLNDGAM_MEM_PWR_FORCE, power_on ? 0 : 3);
+		if (power_on)
+			REG_WAIT(CM_MEM_PWR_STATUS, BLNDGAM_MEM_PWR_STATE, 0, 1, 5);
+	} else {
+		REG_SET(CM_MEM_PWR_CTRL, 0,
+				BLNDGAM_MEM_PWR_FORCE, power_on == true ? 0 : 1);
+	}
 }
 
 static void dpp3_configure_blnd_lut(
···
 
 	if (params == NULL) {
 		REG_SET(CM_BLNDGAM_CONTROL, 0, CM_BLNDGAM_MODE, 0);
+		if (dpp_base->ctx->dc->debug.enable_mem_low_power.bits.cm)
+			dpp3_power_on_blnd_lut(dpp_base, false);
 		return false;
 	}
 

drivers/gpu/drm/amd/display/dc/dcn30/dcn30_dpp.h

···
 	TF_SF(DSCL0_DSCL_MEM_PWR_CTRL, LUT_MEM_PWR_FORCE, mask_sh)
 
 #define DPP_REG_LIST_SH_MASK_DCN30_UPDATED(mask_sh)\
+	TF_SF(CM0_CM_MEM_PWR_STATUS, BLNDGAM_MEM_PWR_STATE, mask_sh), \
 	TF_SF(CM0_CM_BLNDGAM_CONTROL, CM_BLNDGAM_MODE, mask_sh), \
 	TF_SF(CM0_CM_BLNDGAM_CONTROL, CM_BLNDGAM_MODE_CURRENT, mask_sh), \
 	TF_SF(CM0_CM_BLNDGAM_CONTROL, CM_BLNDGAM_SELECT_CURRENT, mask_sh), \
···
 	type CM_BLNDGAM_MODE_CURRENT; \
 	type CM_BLNDGAM_SELECT_CURRENT; \
 	type CM_BLNDGAM_SELECT; \
-	type GAMCOR_MEM_PWR_STATE
+	type GAMCOR_MEM_PWR_STATE; \
+	type BLNDGAM_MEM_PWR_STATE
 
 struct dcn3_dpp_shift {
 	DPP_REG_FIELD_LIST_DCN3(uint8_t);