From mboxrd@z Thu Jan 1 00:00:00 1970 From: khilman@baylibre.com (Kevin Hilman) Date: Wed, 27 Jan 2016 17:16:45 -0800 Subject: MTK mt8173-evb: mainline unstable, and big-endian boot failures In-Reply-To: (Kevin Hilman's message of "Wed, 27 Jan 2016 16:55:25 -0800") References: Message-ID: <7hsi1ilczm.fsf@baylibre.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Kevin Hilman writes: [...] > It seems to be pretty stable up through v4.4 but > unreliable/unpredictable in v4.5-rc1 and lots of places in between. > It's hard to bisect because it doesn't reliably fail, but when it does > fail to finish booting, it's typically after it reaches a shell, and > trying to run various simple shell commands fails to complete, like > this example from next-20160125[2]. > > To me this suggests possibly an issue with the idle driver where > characters might be getting lost on the serial console, which causes > the automated boot scripts to fail because the shell is still waiting > for the command to be finished. FWIW, I think I confirmed my suspicion that it's an idle driver issue because adding 'nohlt' on the cmdline, which forces cpuidle_poll mode (essentially disabling cpuidle) makes mainline boot quite reliably on my mt8173-evb board now. Kevin