drm/amd/display: add a func to disable accelerated mode

[Why]
When driver disabled, we driver force the YCbCr420 to RGB,
which means some register will be changed, such as
RDPCS_PHY_DP_MPLLB_TX_CLK_DIV changed from 1 to 0
When driver re-enabled, OS will Set Mode YCbCr420 again,
which means the register RDPCS_PHY_DP_MPLLB_TX_CLK_DIV
should to be 1 again, but dmub fw can’t update the
register to 1 due to the mpll is not off

[How]
Adds an interface to disable accelerated mode bit,
which allows DM to decide to call during driver
disable/unload scenarios.

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Yao Wang1 <Yao.Wang1@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Solomon Chiu <solomon.chiu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index dffd150180ec..8e6c815b55d2 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -41,6 +41,7 @@
 #include "dc_bios_types.h"
 
 #include "bios_parser_interface.h"
+#include "bios/bios_parser_helper.h"
 #include "include/irq_service_interface.h"
 #include "transform.h"
 #include "dmcu.h"
@@ -3372,3 +3373,20 @@ bool dc_process_dmub_aux_transfer_async(struct dc *dc,
 
 	return true;
 }
+
+/**
+ *****************************************************************************
+ *  Function: dc_disable_accelerated_mode
+ *
+ *  @brief
+ *		disable accelerated mode
+ *
+ *  @param
+ *		[in] dc: dc structure
+ *
+ *****************************************************************************
+ */
+void dc_disable_accelerated_mode(struct dc *dc)
+{
+	bios_set_scratch_acc_mode_change(dc->ctx->dc_bios, 0);
+}