diff options
author | Zhenyu Wang <zhenyuw@linux.intel.com> | 2009-09-25 08:01:28 +0000 |
---|---|---|
committer | Eric Anholt <eric@anholt.net> | 2009-10-13 10:57:10 -0700 |
commit | 58a27471d00dc09945cbcfbbc5cbcdcd3c28211d (patch) | |
tree | f1679ecad026b8f6cb6440156167808195543881 /drivers/gpu/drm/i915/intel_display.c | |
parent | c03342fa6d4617a77cb867ee0ec71665d520eb69 (diff) |
drm/i915: Fix FDI M/N setting according with correct color depth
FDI M/N calculation hasn't taken the current pipe color depth into account,
but always set as 24bpp. This one checks current pipe color depth setting,
and change FDI M/N calculation a little to use bits_per_pixel first, then
convert to bytes_per_pixel later.
This fixes display corrupt issue on Arrandle LVDS with 1600x900 panel
in 18bpp dual-channel mode.
Cc: Stable Team <stable@kernel.org>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_display.c')
-rw-r--r-- | drivers/gpu/drm/i915/intel_display.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index be7fada590d..8278d9d163a 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -2082,7 +2082,7 @@ fdi_reduce_ratio(u32 *num, u32 *den) #define LINK_N 0x80000 static void -igdng_compute_m_n(int bytes_per_pixel, int nlanes, +igdng_compute_m_n(int bits_per_pixel, int nlanes, int pixel_clock, int link_clock, struct fdi_m_n *m_n) { @@ -2092,7 +2092,8 @@ igdng_compute_m_n(int bytes_per_pixel, int nlanes, temp = (u64) DATA_N * pixel_clock; temp = div_u64(temp, link_clock); - m_n->gmch_m = div_u64(temp * bytes_per_pixel, nlanes); + m_n->gmch_m = div_u64(temp * bits_per_pixel, nlanes); + m_n->gmch_m >>= 3; /* convert to bytes_per_pixel */ m_n->gmch_n = DATA_N; fdi_reduce_ratio(&m_n->gmch_m, &m_n->gmch_n); @@ -2766,7 +2767,7 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc, /* FDI link */ if (IS_IGDNG(dev)) { - int lane, link_bw; + int lane, link_bw, bpp; /* eDP doesn't require FDI link, so just set DP M/N according to current link config */ if (is_edp) { @@ -2785,7 +2786,29 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc, lane = 4; link_bw = 270000; } - igdng_compute_m_n(3, lane, target_clock, + + /* determine panel color depth */ + temp = I915_READ(pipeconf_reg); + + switch (temp & PIPE_BPC_MASK) { + case PIPE_8BPC: + bpp = 24; + break; + case PIPE_10BPC: + bpp = 30; + break; + case PIPE_6BPC: + bpp = 18; + break; + case PIPE_12BPC: + bpp = 36; + break; + default: + DRM_ERROR("unknown pipe bpc value\n"); + bpp = 24; + } + + igdng_compute_m_n(bpp, lane, target_clock, link_bw, &m_n); } |