display_bpc might not have been set before comparing with the
requested mode, so wait until afterwards before comparing with the
supported fdi bandwidth. Not a significant change as any case that
mattered would have worked; this just makes the debug messages look nicer.
Signed-off-by: Keith Packard <keithp at keithp.com>
---
drivers/gpu/drm/i915/intel_display.c | 39 ++++++++++++++++++++--------------
1 file changed, 23 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 95248bd..b099a17 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3804,15 +3804,6 @@ static bool intel_choose_pipe_bpp_dither(struct drm_crtc *crtc,
display_bpc = 6;
}
- if (display_bpc * 3 > max_fdi_bpp) {
- if (max_fdi_bpp < 24)
- display_bpc = 6;
- else if (max_fdi_bpp < 30)
- display_bpc = 8;
- else if (max_fdi_bpp < 36)
- display_bpc = 10;
- DRM_DEBUG_KMS("Dithering FDI to %dbpc\n", display_bpc);
- }
/*
* We could just drive the pipe at the highest bpc all the time and
* enable dithering as needed, but that costs bandwidth. So choose
@@ -3845,8 +3836,20 @@ static bool intel_choose_pipe_bpp_dither(struct drm_crtc *crtc,
display_bpc = min(display_bpc, bpc);
- DRM_DEBUG_KMS("setting pipe bpc to %d (max display bpc %d)\n",
- bpc, display_bpc);
+ display_bpc = 6;
+
+ if (display_bpc * 3 > max_fdi_bpp) {
+ if (max_fdi_bpp < 24)
+ display_bpc = 6;
+ else if (max_fdi_bpp < 30)
+ display_bpc = 8;
+ else if (max_fdi_bpp < 36)
+ display_bpc = 10;
+ DRM_DEBUG_KMS("Dithering FDI to %dbpc\n", display_bpc);
+ }
+
+ DRM_DEBUG_KMS("setting pipe bpc to %d (max display bpc %d) (max_fdi_bpp %d)\n",
+ bpc, display_bpc, max_fdi_bpp);
*pipe_bpp = display_bpc * 3;
@@ -4737,8 +4740,7 @@ static int ironlake_crtc_mode_set(struct drm_crtc *crtc,
max_fdi_bpp = 0;
max_lane = lane;
} else {
- u32 fdi_bw;
-
+ u32 fdi_bw, pps;
/* [e]DP over FDI requires target mode clock
instead of link clock */
if (is_dp)
@@ -4763,9 +4765,12 @@ static int ironlake_crtc_mode_set(struct drm_crtc *crtc,
* Compute the available FDI bandwidth, use that
* to compute the maximum supported BPP
*/
- fdi_bw = link_bw * max_lane * 19 / 20;
- max_fdi_bpp = fdi_bw / target_clock;
- DRM_DEBUG_KMS("max lane %d yields max fdi bpp %d\n", max_lane, max_fdi_bpp);
+ fdi_bw = (link_bw * 8) * max_lane;
+ pps = target_clock * 21 / 20;
+
+ max_fdi_bpp = fdi_bw / pps;
+ DRM_DEBUG_KMS("link_bw %d max_lane %d fdi_bw %u pps %u max_fdi_bpp %d\n",
+ link_bw, max_lane, fdi_bw, pps, max_fdi_bpp);
}
/* [e]DP over FDI requires target mode clock instead of link clock. */
@@ -4809,6 +4814,8 @@ static int ironlake_crtc_mode_set(struct drm_crtc *crtc,
*/
u32 bps = target_clock * pipe_bpp * 21 / 20;
lane = bps / (link_bw * 8) + 1;
+ DRM_DEBUG_KMS("target_clock %u pipe_bpp %u bps %u link_bw %u lane %u\n",
+ target_clock, pipe_bpp, bps, link_bw, lane);
if (lane > max_lane) {
DRM_ERROR("Not enough lanes available for mode! (want %d have %d)\n",
lane, max_lane);
--
1.7.10.4
