2015-04-13 5:30 GMT+09:00 Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx>: > Commit ea08de16eb1b ("ARM: dts: Add DISP1 power domain for exynos5420") > added a device node for the Exynos5420 DISP1 power domain but dit not > make the DP controller a consumer of that power domain. > > This causes an "Unhandled fault: imprecise external abort" error if the > exynos-dp driver tries to access the DP controller registers and the PD > was turned off. This lead to a kernel panic and a complete system hang. > > Make the DP controller device node a consumer of the DISP1 power domain > to ensure that the PD is turned on when the exynos-dp driver is probed. > > Fixes: ea08de16eb1b ("ARM: dts: Add DISP1 power domain for exynos5420") > Signed-off-by: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx> > --- > > Hello, > > This latent bug was not exposed before since drivers for other devices > marked as DISP1 power domain consumers were probed before exynos-dp so > the PD was already on which made possible to access the DP registers. > > But "regulator: Defer lookup of supply to regulator_get" [0] that is in > linux-next from a couple of days now, changed the order on which the > drivers' probes succeed so the PD was disabled during exynos-dp probe. > > Exynos5420 machines with a display such as the Exynos5420 Peach Pit and > Exynos5800 Peach Pi were failing to boot due this issue, i.e: [1]. > > Olof, > > Could you please confirm $subject fixes the issue catched by your farm? > > Krzysztof, > > This patch conflicts with your Exynos5 phandle notation cleanup [2] but > I preferred to send it on top of linux-next instead of making your series > a dependency since it fixes a very important bug that had caused -next to > be broken on these matchines for days now. Sure, I don't mind. My patchset is just a cleanup so it can wait and should not block important stuff. Best regards, Krzysztof -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html