[PATCH V2 02/16] mailbox: bcm2835: Fix timeout during suspend mode

[Stefan Wahren]

Hi Jassi,

Am 28.07.24 um 13:41 schrieb Stefan Wahren:
> During noirq suspend phase the Raspberry Pi power driver suffer of
> firmware property timeouts. The reason is that the IRQ of the underlying
> BCM2835 mailbox is disabled and rpi_firmware_property_list() will always
> run into a timeout [1].
>
> Since the VideoCore side isn't consider as a wakeup source, set the
> IRQF_NO_SUSPEND flag for the mailbox IRQ in order to keep it enabled
> during suspend-resume cycle.
>
> [1]
> PM: late suspend of devices complete after 1.754 msecs
> WARNING: CPU: 0 PID: 438 at drivers/firmware/raspberrypi.c:128
>   rpi_firmware_property_list+0x204/0x22c
> Firmware transaction 0x00028001 timeout
> Modules linked in:
> CPU: 0 PID: 438 Comm: bash Tainted: G         C         6.9.3-dirty #17
> Hardware name: BCM2835
> Call trace:
> unwind_backtrace from show_stack+0x18/0x1c
> show_stack from dump_stack_lvl+0x34/0x44
> dump_stack_lvl from __warn+0x88/0xec
> __warn from warn_slowpath_fmt+0x7c/0xb0
> warn_slowpath_fmt from rpi_firmware_property_list+0x204/0x22c
> rpi_firmware_property_list from rpi_firmware_property+0x68/0x8c
> rpi_firmware_property from rpi_firmware_set_power+0x54/0xc0
> rpi_firmware_set_power from _genpd_power_off+0xe4/0x148
> _genpd_power_off from genpd_sync_power_off+0x7c/0x11c
> genpd_sync_power_off from genpd_finish_suspend+0xcc/0xe0
> genpd_finish_suspend from dpm_run_callback+0x78/0xd0
> dpm_run_callback from device_suspend_noirq+0xc0/0x238
> device_suspend_noirq from dpm_suspend_noirq+0xb0/0x168
> dpm_suspend_noirq from suspend_devices_and_enter+0x1b8/0x5ac
> suspend_devices_and_enter from pm_suspend+0x254/0x2e4
> pm_suspend from state_store+0xa8/0xd4
> state_store from kernfs_fop_write_iter+0x154/0x1a0
> kernfs_fop_write_iter from vfs_write+0x12c/0x184
> vfs_write from ksys_write+0x78/0xc0
> ksys_write from ret_fast_syscall+0x0/0x54
> Exception stack(0xcc93dfa8 to 0xcc93dff0)
> [...]
> PM: noirq suspend of devices complete after 3095.584 msecs
>
> Link: https://github.com/raspberrypi/firmware/issues/1894
> Fixes: 0bae6af6d704 ("mailbox: Enable BCM2835 mailbox support")
> Signed-off-by: Stefan Wahren <wahrenst at gmx.net>
> Reviewed-by: Florian Fainelli <florian.fainelli at broadcom.com>
Are there any objections with this patch?

I consider this solution as settled.

Best regards
> ---
>   drivers/mailbox/bcm2835-mailbox.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mailbox/bcm2835-mailbox.c b/drivers/mailbox/bcm2835-mailbox.c
> index fbfd0202047c..ea12fb8d2401 100644
> --- a/drivers/mailbox/bcm2835-mailbox.c
> +++ b/drivers/mailbox/bcm2835-mailbox.c
> @@ -145,7 +145,8 @@ static int bcm2835_mbox_probe(struct platform_device *pdev)
>   	spin_lock_init(&mbox->lock);
>
>   	ret = devm_request_irq(dev, irq_of_parse_and_map(dev->of_node, 0),
> -			       bcm2835_mbox_irq, 0, dev_name(dev), mbox);
> +			       bcm2835_mbox_irq, IRQF_NO_SUSPEND, dev_name(dev),
> +			       mbox);
>   	if (ret) {
>   		dev_err(dev, "Failed to register a mailbox IRQ handler: %d\n",
>   			ret);
> --
> 2.34.1
>