cca61191a8
[ Upstream commit ab47d0bfdf88faac0eb02749e5bfaa306e004300 ]
Some services explicitly return an error code in their response, but
others rely on the system controller to set a status in its status
register. The meaning of the bits varies based on what service is
requested, so pass it back up to the driver that requested the service
in the first place. The field in the message struct already existed, but
was unused until now.
If the system controller is busy, in which case we should never actually
be in the interrupt handler, or if the service fails the mailbox itself
should not be read. Callers should check the status before operating on
the response.
There's an existing, but unused, #define for the mailbox mask - but it
was incorrect. It was doing a GENMASK_ULL(32, 16) which should've just
been a GENMASK(31, 16), so fix that up and start using it.
Fixes: 83d7b1560810 ("mbox: add polarfire soc system controller mailbox")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.