drm/amd/display: Set DFS bypass flags for dce110

[Why]

While there is support for using and quering DFS bypass clocks the
hardware is never notified to enter DFS bypass mode for dce110.

[How]

Add a flag that can be set when programming the display engine PLL
to enable DFS bypass mode. If this flag is set then the hardware is
notified to enter DFS bypass mode and the correct display engine clock
frequency can be acquired.

Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/bios/command_table.c b/drivers/gpu/drm/amd/display/dc/bios/command_table.c
index a558bfa..2bd7cd9 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/bios/command_table.c
+++ b/drivers/gpu/drm/amd/display/dc/bios/command_table.c
@@ -2201,6 +2201,9 @@ static enum bp_result program_clock_v6(
        if (bp_params->flags.SET_EXTERNAL_REF_DIV_SRC)
                params.sPCLKInput.ucMiscInfo |= PIXEL_CLOCK_MISC_REF_DIV_SRC;
 
+       if (bp_params->flags.SET_DISPCLK_DFS_BYPASS)
+               params.sPCLKInput.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_DPREFCLK_BYPASS;
+
        if (EXEC_BIOS_CMD_TABLE(SetPixelClock, params)) {
                /* True display clock is returned by VBIOS if DFS bypass
                 * is enabled. */

diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_clocks.c b/drivers/gpu/drm/amd/display/dc/dce/dce_clocks.c
index fb1f373..0782b74 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_clocks.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_clocks.c
@@ -255,6 +255,9 @@ static int dce_set_clock(
        pxl_clk_params.target_pixel_clock = requested_clk_khz;
        pxl_clk_params.pll_id = CLOCK_SOURCE_ID_DFS;
 
+       if (clk_dce->dfs_bypass_enabled)
+               pxl_clk_params.flags.SET_DISPCLK_DFS_BYPASS = true;
+
        bp->funcs->program_display_engine_pll(bp, &pxl_clk_params);
 
        if (clk_dce->dfs_bypass_enabled) {

diff --git a/drivers/gpu/drm/amd/display/include/bios_parser_types.h b/drivers/gpu/drm/amd/display/include/bios_parser_types.h
index 0840f69..f8dbfa5 100644 (file)
--- a/drivers/gpu/drm/amd/display/include/bios_parser_types.h
+++ b/drivers/gpu/drm/amd/display/include/bios_parser_types.h
@@ -234,6 +234,8 @@ struct bp_pixel_clock_parameters {
                uint32_t USE_E_CLOCK_AS_SOURCE_FOR_D_CLOCK:1;
                /* Use external reference clock (refDivSrc for PLL) */
                uint32_t SET_EXTERNAL_REF_DIV_SRC:1;
+               /* Use DFS bypass for Display clock. */
+               uint32_t SET_DISPCLK_DFS_BYPASS:1;
                /* Force program PHY PLL only */
                uint32_t PROGRAM_PHY_PLL_ONLY:1;
                /* Support for YUV420 */