drm/amd/display: program fbc for scatter/gather

Fixing screen flickering when FBC enabled on Stoney

Signed-off-by: Roman Li <Roman.Li@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dce110/dce110_compressor.c b/drivers/gpu/drm/amd/display/dc/dce110/dce110_compressor.c
index 2e97e57..f82c269 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce110/dce110_compressor.c
+++ b/drivers/gpu/drm/amd/display/dc/dce110/dce110_compressor.c
@@ -189,7 +189,7 @@ void dce110_compressor_enable_fbc(
                (!dce110_compressor_is_fbc_enabled_in_hw(compressor, NULL))) {
 
                uint32_t addr;
-               uint32_t value;
+               uint32_t value, misc_value;
 
 
                addr = mmFBC_CNTL;
@@ -206,9 +206,23 @@ void dce110_compressor_enable_fbc(
                compressor->attached_inst = params->inst;
                cp110->offsets = reg_offsets[params->inst];
 
-               /*Toggle it as there is bug in HW */
+               /* Toggle it as there is bug in HW */
                set_reg_field_value(value, 0, FBC_CNTL, FBC_GRPH_COMP_EN);
                dm_write_reg(compressor->ctx, addr, value);
+
+               /* FBC usage with scatter & gather for dce110 */
+               misc_value = dm_read_reg(compressor->ctx, mmFBC_MISC);
+
+               set_reg_field_value(misc_value, 1,
+                               FBC_MISC, FBC_INVALIDATE_ON_ERROR);
+               set_reg_field_value(misc_value, 1,
+                               FBC_MISC, FBC_DECOMPRESS_ERROR_CLEAR);
+               set_reg_field_value(misc_value, 0x14,
+                               FBC_MISC, FBC_SLOW_REQ_INTERVAL);
+
+               dm_write_reg(compressor->ctx, mmFBC_MISC, misc_value);
+
+               /* Enable FBC */
                set_reg_field_value(value, 1, FBC_CNTL, FBC_GRPH_COMP_EN);
                dm_write_reg(compressor->ctx, addr, value);