Hi Kukjin, Please consider this patch for your branch. This patch is important for Display for Exynos5 boards. Regards, Rahul Sharma. On 9 July 2014 17:00, Rahul Sharma <rahul.sharma@xxxxxxxxxxx> wrote: > Hi Tomasz, > > On 8 July 2014 21:04, Tomasz Figa <t.figa@xxxxxxxxxxx> wrote: >> Hi Rahul, >> >> On 07.07.2014 15:37, Rahul Sharma wrote: >>> Hi Andrej, Inki, >>> >>> On 18 June 2014 12:06, Rahul Sharma <rahul.sharma@xxxxxxxxxxx> wrote: >>>> Hi Andrej, >>>> >>>> On 18 June 2014 11:46, Andrzej Hajda <a.hajda@xxxxxxxxxxx> wrote: >>>>> On 06/17/2014 07:49 AM, Rahul Sharma wrote: >>>>>> Hi All, >>>>>> >>>>>> Please review this patch. >>>>>> >>>>>> Regards, >>>>>> Rahul Sharma >>>>>> >>>>>> On 9 June 2014 16:58, Rahul Sharma <rahul.sharma@xxxxxxxxxxx> wrote: >>>>>>> Display domain is removed due to instability issues. Explaining >>>>>>> the problem below: >>>>>>> >>>>>>> exynos_init_late triggers the pm_genpd_poweroff_unused which >>>>>>> powers off the unused power domains. This call hits before >>>>>>> the trigger to deferred probes. >>>>>>> >>>>>>> DRM DP Panel defers the probe due to supply get failure. By the >>>>>>> time, deferred probe is scheduled again, Display Power Domain is >>>>>>> powered off by pm_genpd_poweroff_unused. >>>>>>> >>>>>>> FIMD and DP drivers are accessing registers during Probe and Bind >>>>>>> callbacks. If display domain is enabled/disabled around register >>>>>>> accesses, display domain gets unstable and we are getting Power >>>>>>> Domain Disable fail notification. Increasing the Timeout also >>>>>>> didn't help. >>>>> >>>>> As I understand the problem is that fimd and dp drivers access hw >>>>> registers without enabling power domain. So the proper solution is to >>>>> fix these drivers. >>>> >>>> That is also a problem but I fixed those accesses in my local kernel before >>>> hitting this issue. If we do register accesses in FIMD/DP probe/bind we >>>> observes "Prefetch abort" exception. But here the problem is that 'DP >>>> domain disable' starts failing if we enable/disable multiple times. >>>> >>>>> >>>>> Btw. there are already patches removing hw access from probe/bind of >>>>> fimd. I guess removing also hw access from dp probe/bind could be a good >>>>> solution. >>>> >>>> Please let me know the links for posted patches. I will test with those patches. >>> >>> Is there any update on this? Please share the patches which fixes the >>> above issue or avoid the above scenario of multiple PM Domain enable/disable. >>> I will test them for exynos5 based boards. Otherwise we should get this change >>> merged else display will remain broken for exynos5 based boards. >> >> Andrzej is on holidays right now, so he won't be able to reply in this >> thread until he's back. Here are two patches I was able to find on the >> related MLs that might be fixing the cause of your issues: > > Ok. thanks for the update. > > We should test with Ajay's patches which includes DP probe deferring > based on availability of bridge chip. + > > few patches which cleanup register access in FIMD and DP probe/bind > OR > few patches to enable Display power domain and clocks just before the > register access. As done in https://lkml.org/lkml/2014/7/4/188. > > Later solution results into display power domain enable failure in case of DRM > probe defer. > > I am just curious if Andrej has some solution for the first approach which can > be tested for defer probe and S2R scenarios. > > Regards, > Rahul Sharma. > >> >> [PATCH] drm/exynos: remove hardware overlays disable from fimd probe >> (https://www.mail-archive.com/linux-samsung-soc@xxxxxxxxxxxxxxx/msg31629.html) >> >> [PATCH] drm/exynos: fimd: Keep power enabled during fimd_bind >> (https://lkml.org/lkml/2014/7/4/188) >> >> Best regards, >> Tomasz >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
