From 9ea5487ea51a2279633410ee7a70168e0253223c Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Fri, 11 Aug 2023 17:49:58 -0700 Subject: [PATCH] ipq806x: chromium: Disable kernel's CONFIG_QCOM_SPM The qcom spm driver is currently broken for IPQ8064 OnHub devices on kernel 6.1, such that it hangs the system when booting, much to the consternation of users. This is especially bad as these devices don't yet have a fully-supported release branch, and are still sometimes landing on snapshot builds. OnHub devices have their own kernel config, so it's not that wide of an impact to disable this. I haven't fully gotten to the bottom of this, but: (a) The vendor kernel didn't have any SPM driver at all, and didn't utilize cpuidle. (b) The device tree has never included any (non-disabled) cpuidle states, so even when this driver was present on 5.15 (last known-working kernel), it didn't actually do anything -- it bailed early, before ever doing any SPM initialization. (c) Refactoring in Linux 5.16 [1] caused the SPM driver to be activated unconditionally, including setting us into standby mode (PM_SLEEP_MODE_STBY) by default. Removing the one PM_SLEEP_MODE_STBY line from drivers/soc/qcom/spm.c seems to fix the problem, but that isn't much different than simply disabling the driver, so I go with that for now. I also disable CONFIG_ARM_QCOM_SPM_CPUIDLE, becuase it 'select's QCOM_SPM. NB: it's possible there's some other deeper root cause involved in here. For one, I notice that CPU hotplug (e.g., echo 0 > /sys/devices/system/cpu/cpu1/online, echo 1 > ...) doesn't work right either. Perhaps there's some mismatch on upstream Linux qcom-scm behavior and the old boot firmware used for these systems? It wouldn't be the first time, as we've had some similar incompatibilities on the next generation of these devices, Google WiFi [2]. [1] Commit 60f3692b5f0b ("cpuidle: qcom_spm: Detach state machine from main SPM handling") [2] [RFC] qcom_scm: IPQ4019 firmware does not support atomic API? https://lore.kernel.org/linux-arm-kernel/20200913201608.GA3162100@bDebian/ Signed-off-by: Brian Norris --- target/linux/ipq806x/chromium/config-default | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/linux/ipq806x/chromium/config-default b/target/linux/ipq806x/chromium/config-default index d7db9f7db3..927aba360f 100644 --- a/target/linux/ipq806x/chromium/config-default +++ b/target/linux/ipq806x/chromium/config-default @@ -1,7 +1,9 @@ +# CONFIG_ARM_QCOM_SPM_CPUIDLE is not set CONFIG_BLK_DEV_SD=y CONFIG_LEDS_LP5523=y CONFIG_LEDS_LP55XX_COMMON=y CONFIG_PHY_QCOM_IPQ806X_USB=y +# CONFIG_QCOM_SPM is not set CONFIG_SCSI=y CONFIG_SCSI_COMMON=y CONFIG_SG_POOL=y -- 2.30.2