[PATCH 01/15] ARM: OMAP2+: mailbox: Add an API for flushing the FIFO

Tony Lindgren tony at atomide.com
Fri Nov 2 15:00:04 EDT 2012


* Vaibhav Bedia <vaibhav.bedia at ti.com> [121102 05:35]:
> On AM33XX, the mailbox module between the MPU and the
> WKUP-M3 co-processor facilitates a one-way communication.
> MPU uses the assigned mailbox sub-module to issue the
> interrupt to the WKUP-M3 co-processor which then goes
> and reads the the IPC data from registers in the control
> module.
> 
> WKUP-M3 is in the L4_WKUP and does not have any access to
> the Mailbox module. Due to this limitation, the MPU is
> completely responsible for FIFO maintenance and interrupt
> generation. MPU needs to ensure that the FIFO does not
> overflow by reading by the assigned mailbox sub-module.
> 
> This patch adds an API in the mailbox code which the MPU
> can use to empty the FIFO by issuing a readback command.
> 
> Signed-off-by: Vaibhav Bedia <vaibhav.bedia at ti.com>
> ---
>  arch/arm/mach-omap2/mailbox.c             |   42 ++++++++++++++++++++---------
>  arch/arm/plat-omap/include/plat/mailbox.h |    3 ++
>  arch/arm/plat-omap/mailbox.c              |   35 ++++++++++++++++++++++++

Patches have been posted to move the mailbox related
files out of arch/arm, so you'll have to update those
for that. Please see thread "[PATCH 0/2] ARM: OMAP:
mailbox out of plat code" for more information.

Regards,

Tony



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