From 02d27234759dc4fe14a880ec1e1dee108cb0b503 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Thu, 3 Mar 2016 19:34:28 -0500 Subject: [PATCH] drm/amdgpu/dp: add back special handling for NUTMEG MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When I fixed the dp rate selection in: 3b73b168cffd9c392584d3f665021fa2190f8612 drm/amdgpu: fix dp link rate selection (v2) I accidently dropped the special handling for NUTMEG DP bridge chips. They require a fixed link rate. Reviewed-by: Christian König Reviewed-by: Ken Wang Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/amd/amdgpu/atombios_dp.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c index 21aacc1f45c1..bf731e9f643e 100644 --- a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c +++ b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c @@ -265,15 +265,27 @@ static int amdgpu_atombios_dp_get_dp_link_config(struct drm_connector *connector unsigned max_lane_num = drm_dp_max_lane_count(dpcd); unsigned lane_num, i, max_pix_clock; - for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) { - for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) { - max_pix_clock = (lane_num * link_rates[i] * 8) / bpp; + if (amdgpu_connector_encoder_get_dp_bridge_encoder_id(connector) == + ENCODER_OBJECT_ID_NUTMEG) { + for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) { + max_pix_clock = (lane_num * 270000 * 8) / bpp; if (max_pix_clock >= pix_clock) { *dp_lanes = lane_num; - *dp_rate = link_rates[i]; + *dp_rate = 270000; return 0; } } + } else { + for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) { + for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) { + max_pix_clock = (lane_num * link_rates[i] * 8) / bpp; + if (max_pix_clock >= pix_clock) { + *dp_lanes = lane_num; + *dp_rate = link_rates[i]; + return 0; + } + } + } } return -EINVAL; -- 2.20.1