| From ff0bd441bdfbfa09d05fdba9829a0401a46635c1 Mon Sep 17 00:00:00 2001 |
| From: Alex Deucher <alexander.deucher@amd.com> |
| Date: Wed, 11 May 2016 16:16:53 -0400 |
| Subject: drm/radeon: fix DP mode validation |
| |
| From: Alex Deucher <alexander.deucher@amd.com> |
| |
| commit ff0bd441bdfbfa09d05fdba9829a0401a46635c1 upstream. |
| |
| Switch the order of the loops to walk the rates on the top |
| so we exhaust all DP 1.1 rate/lane combinations before trying |
| DP 1.2 rate/lane combos. |
| |
| This avoids selecting rates that are supported by the monitor, |
| but not the connector leading to valid modes getting rejected. |
| |
| bug: |
| https://bugs.freedesktop.org/show_bug.cgi?id=95206 |
| |
| Signed-off-by: Alex Deucher <alexander.deucher@amd.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/gpu/drm/radeon/atombios_dp.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/gpu/drm/radeon/atombios_dp.c |
| +++ b/drivers/gpu/drm/radeon/atombios_dp.c |
| @@ -326,8 +326,8 @@ int radeon_dp_get_dp_link_config(struct |
| } |
| } |
| } 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++) { |
| + for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) { |
| + for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) { |
| max_pix_clock = (lane_num * link_rates[i] * 8) / bpp; |
| if (max_pix_clock >= pix_clock) { |
| *dp_lanes = lane_num; |
