drm/amdgpu: adjust default display clock

Increase the default display clock on newer asics to
accomodate some high res modes with really high refresh
rates.

bug: https://bugs.freedesktop.org/show_bug.cgi?id=93826
Acked-by: Chunming Zhou <david1.zhou@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c

@@ -693,6 +693,10 @@ int amdgpu_atombios_get_clock_info(struct amdgpu_device *adev)
 			DRM_INFO("Changing default dispclk from %dMhz to 600Mhz\n",
 				 adev->clock.default_dispclk / 100);
 			adev->clock.default_dispclk = 60000;
+		} else if (adev->clock.default_dispclk <= 60000) {
+			DRM_INFO("Changing default dispclk from %dMhz to 625Mhz\n",
+				 adev->clock.default_dispclk / 100);
+			adev->clock.default_dispclk = 62500;
 		}
 		adev->clock.dp_extclk =
 			le16_to_cpu(firmware_info->info_21.usUniphyDPModeExtClkFreq);