[PATCH 1/2] adreno: Shutdown the GPU properly

From: Joel Fernandes (Google)
Date: Fri Nov 11 2022 - 14:50:21 EST


During kexec on ARM device, we notice that device_shutdown() only calls
pm_runtime_force_suspend() while shutting down the GPU. This means the GPU
kthread is still running and further, there maybe active submits.

This causes all kinds of issues during a kexec reboot:

Warning from shutdown path:

[ 292.509662] WARNING: CPU: 0 PID: 6304 at [...] adreno_runtime_suspend+0x3c/0x44
[ 292.509863] Hardware name: Google Lazor (rev3 - 8) with LTE (DT)
[ 292.509872] pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 292.509881] pc : adreno_runtime_suspend+0x3c/0x44
[ 292.509891] lr : pm_generic_runtime_suspend+0x30/0x44
[ 292.509905] sp : ffffffc014473bf0
[...]
[ 292.510043] Call trace:
[ 292.510051] adreno_runtime_suspend+0x3c/0x44
[ 292.510061] pm_generic_runtime_suspend+0x30/0x44
[ 292.510071] pm_runtime_force_suspend+0x54/0xc8
[ 292.510081] adreno_shutdown+0x1c/0x28
[ 292.510090] platform_shutdown+0x2c/0x38
[ 292.510104] device_shutdown+0x158/0x210
[ 292.510119] kernel_restart_prepare+0x40/0x4c

And here from GPU kthread, an SError OOPs:

[ 192.648789] el1h_64_error+0x7c/0x80
[ 192.648812] el1_interrupt+0x20/0x58
[ 192.648833] el1h_64_irq_handler+0x18/0x24
[ 192.648854] el1h_64_irq+0x7c/0x80
[ 192.648873] local_daif_inherit+0x10/0x18
[ 192.648900] el1h_64_sync_handler+0x48/0xb4
[ 192.648921] el1h_64_sync+0x7c/0x80
[ 192.648941] a6xx_gmu_set_oob+0xbc/0x1fc
[ 192.648968] a6xx_hw_init+0x44/0xe38
[ 192.648991] msm_gpu_hw_init+0x48/0x80
[ 192.649013] msm_gpu_submit+0x5c/0x1a8
[ 192.649034] msm_job_run+0xb0/0x11c
[ 192.649058] drm_sched_main+0x170/0x434
[ 192.649086] kthread+0x134/0x300
[ 192.649114] ret_from_fork+0x10/0x20

Fix by calling adreno_system_suspend() in the device_shutdown() path.

Cc: Rob Clark <robdclark@xxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
Cc: Ross Zwisler <zwisler@xxxxxxxxxx>
Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/msm/adreno/adreno_device.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c b/drivers/gpu/drm/msm/adreno/adreno_device.c
index 24b489b6129a..f0cff62812c3 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_device.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_device.c
@@ -607,9 +607,12 @@ static int adreno_remove(struct platform_device *pdev)
return 0;
}

+static int adreno_system_suspend(struct device *dev);
static void adreno_shutdown(struct platform_device *pdev)
{
- pm_runtime_force_suspend(&pdev->dev);
+ struct msm_gpu *gpu = dev_to_gpu(&pdev->dev);
+
+ WARN_ON_ONCE(adreno_system_suspend(&pdev->dev));
}

static const struct of_device_id dt_match[] = {
--
2.38.1.493.g58b659f92b-goog