drm/amd/display: check if REFCLK_CNTL register is present

Check before programming the register since it isn't present on
all IPs using this code.

Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Eric Bernstein <Eric.Bernstein@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
index 22f421e82733b04fa91ca859d5d8ab00646e4f4c..a023a4d59f412ed76cb1fc8308c358c8925f8711 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
@@ -2294,7 +2294,8 @@ void dcn20_fpga_init_hw(struct dc *dc)
 
        REG_UPDATE(DCHUBBUB_GLOBAL_TIMER_CNTL, DCHUBBUB_GLOBAL_TIMER_REFDIV, 2);
        REG_UPDATE(DCHUBBUB_GLOBAL_TIMER_CNTL, DCHUBBUB_GLOBAL_TIMER_ENABLE, 1);
-       REG_WRITE(REFCLK_CNTL, 0);
+       if (REG(REFCLK_CNTL))
+               REG_WRITE(REFCLK_CNTL, 0);
        //