On Tue, Jul 09, 2013 at 01:40:37PM +0300, Imre Deak wrote: > DP 1.2 compatible displays may report a 5.4Gbps maximum bandwidth which > the driver will treat as an invalid value and use 1.62Gbps instead. Fix > this by capping to 2.7Gbps anything beyond the DP 1.1 bandwidth range.
Comments inline. > Signed-off-by: Imre Deak <[email protected]> > --- > drivers/gpu/drm/i915/intel_dp.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c > index 11eb697..c6dd61f 100644 > --- a/drivers/gpu/drm/i915/intel_dp.c > +++ b/drivers/gpu/drm/i915/intel_dp.c > @@ -71,11 +71,16 @@ intel_dp_max_link_bw(struct intel_dp *intel_dp) > { > int max_link_bw = intel_dp->dpcd[DP_MAX_LINK_RATE]; > > + if (max_link_bw > DP_LINK_BW_2_7) > + return DP_LINK_BW_2_7; > + > switch (max_link_bw) { I think putting it here is preferrable: case DP_LINK_BW_5_4: /* 1.2 capable displays may advertise higher bw */ max_link_bw = DP_LINK_BW_2_7; break; Then we still get the WARN for unknown values greater than 0xa. > case DP_LINK_BW_1_62: > case DP_LINK_BW_2_7: > break; > default: > + WARN(1, "invalid max DP link bw val %x, using 1.62Gbps\n", > + max_link_bw); > max_link_bw = DP_LINK_BW_1_62; > break; -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
