From: Imre Deak Date: Wed, 29 Nov 2017 17:51:37 +0000 (+0200) Subject: drm/i915: Avoid PPS HW/SW state mismatch due to rounding X-Git-Tag: archive/raspbian/4.9.82-1+deb9u3+rpi1_jessie~7^2~6 X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/%22mailto:kde%40ewsoftware.de//%22style.css/%22/%22http:/www.example.com/%22mailto:kde%40ewsoftware.de/%22style.css/%22?a=commitdiff_plain;h=3169a7c06e913d3575713753f0807554b1165996;p=linux-4.9.git drm/i915: Avoid PPS HW/SW state mismatch due to rounding commit 5643205c6340b565a3be0fe0e7305dc4aa551c74 upstream. We store a SW state of the t11_t12 timing in 100usec units but have to program it in 100msec as required by HW. The rounding used during programming means there will be a mismatch between the SW and HW states of this value triggering a "PPS state mismatch" error. Avoid this by storing the already rounded-up value in the SW state. Note that we still calculate panel_power_cycle_delay with the finer 100usec granularity to avoid any needless waits using that version of the delay. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103903 Cc: joks Signed-off-by: Imre Deak Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20171129175137.2889-1-imre.deak@intel.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 7fdc42e5aac8..74163a928cba 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -5063,6 +5063,12 @@ intel_dp_init_panel_power_sequencer(struct drm_device *dev, */ final->t8 = 1; final->t9 = 1; + + /* + * HW has only a 100msec granularity for t11_t12 so round it up + * accordingly. + */ + final->t11_t12 = roundup(final->t11_t12, 100 * 10); } static void