LPT is pch, so might run into the fdi bandwidth constraint (especially since it has only 2 lanes). But right now we just force pipe_bpp back to 24, resulting in a nice loop (which we bail out with a loud WARN_ON). Fix this. Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> References: https://bugs.freedesktop.org/show_bug.cgi?id=93477 Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_crt.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c index a2a31fd01d1d..3fbb6fc66451 100644 --- a/drivers/gpu/drm/i915/intel_crt.c +++ b/drivers/gpu/drm/i915/intel_crt.c @@ -261,8 +261,14 @@ static bool intel_crt_compute_config(struct intel_encoder *encoder, pipe_config->has_pch_encoder = true; /* LPT FDI RX only supports 8bpc. */ - if (HAS_PCH_LPT(dev)) + if (HAS_PCH_LPT(dev)) { + if (pipe_config->bw_constrained && pipe_config->pipe_bpp < 24) { + DRM_DEBUG_KMS("LPT only supports 24bpp\n"); + return false; + } + pipe_config->pipe_bpp = 24; + } /* FDI must always be 2.7 GHz */ if (HAS_DDI(dev)) -- 2.8.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx