diff options
| author | Adam Jackson <ajax@redhat.com> | 2011-12-14 03:41:00 +0400 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2011-12-16 20:49:59 +0400 |
| commit | 3b5c78a35cf7511c15e09a9b0ffab290a42d9bcf (patch) | |
| tree | 1ac33469f850f6c84df493974cf6034991dcd0c1 /drivers/gpu/drm/i915/intel_dp.c | |
| parent | f45b55575cedb7efa782e43f1ea74338456d0381 (diff) | |
| download | linux-3b5c78a35cf7511c15e09a9b0ffab290a42d9bcf.tar.xz | |
drm/i915/dp: Dither down to 6bpc if it makes the mode fit
Some active adaptors (VGA usually) only have two lanes at 2.7GHz.
That's a maximum pixel clock of 144MHz at 8bpc, but 192MHz at 6bpc.
Fixes Asus UX31 panel being black at startup due to no valid modes since
dc22ee6fc18ce0f15424e753e8473c306ece95c1.
v2: Rebased to current code, resulting in the fix applying to EDP panels as
well. Also changed from spatio-temporal to just spatial dithering on
pre-ironlake, to be conssitent (and less visual flicker)
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Tested-by: Eric Anholt <eric@anholt.net>
Tested-by: Dirk Hohndel <hohndel@infradead.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_dp.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_dp.c | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 294f55788f0b..92b041b66e49 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -208,13 +208,15 @@ intel_dp_link_clock(uint8_t link_bw) */ static int -intel_dp_link_required(struct intel_dp *intel_dp, int pixel_clock) +intel_dp_link_required(struct intel_dp *intel_dp, int pixel_clock, int check_bpp) { struct drm_crtc *crtc = intel_dp->base.base.crtc; struct intel_crtc *intel_crtc = to_intel_crtc(crtc); int bpp = 24; - if (intel_crtc) + if (check_bpp) + bpp = check_bpp; + else if (intel_crtc) bpp = intel_crtc->bpp; return (pixel_clock * bpp + 9) / 10; @@ -233,6 +235,7 @@ intel_dp_mode_valid(struct drm_connector *connector, struct intel_dp *intel_dp = intel_attached_dp(connector); int max_link_clock = intel_dp_link_clock(intel_dp_max_link_bw(intel_dp)); int max_lanes = intel_dp_max_lane_count(intel_dp); + int max_rate, mode_rate; if (is_edp(intel_dp) && intel_dp->panel_fixed_mode) { if (mode->hdisplay > intel_dp->panel_fixed_mode->hdisplay) @@ -242,9 +245,17 @@ intel_dp_mode_valid(struct drm_connector *connector, return MODE_PANEL; } - if (intel_dp_link_required(intel_dp, mode->clock) - > intel_dp_max_data_rate(max_link_clock, max_lanes)) - return MODE_CLOCK_HIGH; + mode_rate = intel_dp_link_required(intel_dp, mode->clock, 0); + max_rate = intel_dp_max_data_rate(max_link_clock, max_lanes); + + if (mode_rate > max_rate) { + mode_rate = intel_dp_link_required(intel_dp, + mode->clock, 18); + if (mode_rate > max_rate) + return MODE_CLOCK_HIGH; + else + mode->private_flags |= INTEL_MODE_DP_FORCE_6BPC; + } if (mode->clock < 10000) return MODE_CLOCK_LOW; @@ -672,6 +683,7 @@ intel_dp_mode_fixup(struct drm_encoder *encoder, struct drm_display_mode *mode, int lane_count, clock; int max_lane_count = intel_dp_max_lane_count(intel_dp); int max_clock = intel_dp_max_link_bw(intel_dp) == DP_LINK_BW_2_7 ? 1 : 0; + int bpp = mode->private_flags & INTEL_MODE_DP_FORCE_6BPC ? 18 : 0; static int bws[2] = { DP_LINK_BW_1_62, DP_LINK_BW_2_7 }; if (is_edp(intel_dp) && intel_dp->panel_fixed_mode) { @@ -689,7 +701,7 @@ intel_dp_mode_fixup(struct drm_encoder *encoder, struct drm_display_mode *mode, for (clock = 0; clock <= max_clock; clock++) { int link_avail = intel_dp_max_data_rate(intel_dp_link_clock(bws[clock]), lane_count); - if (intel_dp_link_required(intel_dp, mode->clock) + if (intel_dp_link_required(intel_dp, mode->clock, bpp) <= link_avail) { intel_dp->link_bw = bws[clock]; intel_dp->lane_count = lane_count; |