drm/amd/display: Enable Dynamic DTBCLK Switch

[WHAT]
Since dcn35, DTBCLK can be disabled when no DP2 sink connected for
power saving purpose.

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 8e1622bf7a429f538ab27508a8f307ebb6ee15ca..0d03e324d5b9b403c4fe2783f228e8ce53686e17 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2000,6 +2000,10 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
 
        init_data.flags.disable_ips_in_vpb = 0;
 
+       /* DCN35 and above supports dynamic DTBCLK switch */
+       if (amdgpu_ip_version(adev, DCE_HWIP, 0) >= IP_VERSION(3, 5, 0))
+               init_data.flags.allow_0_dtb_clk = true;
+
        /* Enable DWB for tested platforms only */
        if (amdgpu_ip_version(adev, DCE_HWIP, 0) >= IP_VERSION(3, 0, 0))
                init_data.num_virtual_links = 1;