This is a note to let you know that I've just added the patch titled drm/panfrost: devfreq: set opp to the recommended one to configure regulator to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-panfrost-devfreq-set-opp-to-the-recommended-one-.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2d9b89a5a3bc2c99427213c084fe477a381fcb49 Author: Clément Péron <peron.clem@xxxxxxxxx> Date: Tue Sep 6 17:30:33 2022 +0200 drm/panfrost: devfreq: set opp to the recommended one to configure regulator [ Upstream commit d76034a427a2660b080bc155e4fd8f6393eefb48 ] Enabling panfrost GPU OPP with dynamic regulator will make OPP responsible to enable and configure it. Unfortunately OPP configure and enable the regulator when an OPP is asked to be set, which is not the case during panfrost_devfreq_init(). This leave the regulator unconfigured and if no GPU load is triggered, no OPP is asked to be set which make the regulator framework switching it off during regulator_late_cleanup() without noticing and therefore make the board hang as any access to GPU memory space make bus locks up. Call dev_pm_opp_set_opp() with the recommend OPP in panfrost_devfreq_init() to enable the regulator, this will properly configure and enable the regulator and will avoid any switch off by regulator_late_cleanup(). Suggested-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx> Signed-off-by: Clément Péron <peron.clem@xxxxxxxxx> Reviewed-by: Steven Price <steven.price@xxxxxxx> Signed-off-by: Steven Price <steven.price@xxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20220906153034.153321-5-peron.clem@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c index 194af7f607a6..be36dd060a2b 100644 --- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c @@ -132,6 +132,17 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev) return PTR_ERR(opp); panfrost_devfreq_profile.initial_freq = cur_freq; + + /* + * Set the recommend OPP this will enable and configure the regulator + * if any and will avoid a switch off by regulator_late_cleanup() + */ + ret = dev_pm_opp_set_opp(dev, opp); + if (ret) { + DRM_DEV_ERROR(dev, "Couldn't set recommended OPP\n"); + return ret; + } + dev_pm_opp_put(opp); /*