[PATCH RESEND v3 3/4] firmware: raspberrypi: Add reboot mode support

[Gregor Herburger]

On Thu, Sep 03, 2026 at 08:08:22PM +0200, Stefan Wahren wrote:
> Hi Gregor,
> 
> Am 03.09.26 um 16:48 schrieb Gregor Herburger:
> > The Raspberry Pi firmware has a tryboot mode where it tries to boot from
> > another partition. This can be used to create a A/B update scheme.
> > 
> > To enable this on the next boot, the RPI_FIRMWARE_SET_REBOOT_FLAGS
> > message must be sent to the firmware. Add support for this by
> > registering a reboot mode driver.
> > 
> > Furthermore, safely registering the reboot mode requires adjusting the
> > teardown sequence. Replace the manually called rpi_firmware_put() with a
> > devres-managed called (devm_add_action_or_reset). Without this, the
> > cleanup function of devm_reboot_mode_register() would trigger a
> > use-after-free error by attempting to access the firmware context after
> > it had already been freed by rpi_firmware_remove().
> > 
> > Signed-off-by: Gregor Herburger <gregor.herburger at linutronix.de>
> > ---
> >   drivers/firmware/Kconfig                   |  2 ++
> >   drivers/firmware/raspberrypi.c             | 40 ++++++++++++++++++++++++++----
> >   include/soc/bcm2835/raspberrypi-firmware.h |  2 ++
> >   3 files changed, 39 insertions(+), 5 deletions(-)
> > 
> > diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
> > index bbd2155d84838..34605bf7c9734 100644
> > --- a/drivers/firmware/Kconfig
> > +++ b/drivers/firmware/Kconfig
> > @@ -115,6 +115,8 @@ config ISCSI_IBFT
> >   config RASPBERRYPI_FIRMWARE
> >   	tristate "Raspberry Pi Firmware Driver"
> >   	depends on BCM2835_MBOX
> > +	select POWER_RESET
> > +	select REBOOT_MODE
> >   	help
> >   	  This option enables support for communicating with the firmware on the
> >   	  Raspberry Pi.
> > 
> this part doesn't apply anymore. Did you rebased against 7.3-rc1 ?
I have not rebased. I just sent the series out again to get some feedback. I
will rebase it and send it again. Sashiko found an issue anyways.

> 
> Best regards

Best regards
-- 
Gregor Herburger
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