Re: [PATCH v7 01/11] arm_mpam: let low level MSC accessors return an error

[Gavin Shan]

On 8/1/26 3:03 AM, Andre Przywara wrote:
> The upcoming MPAM-Fb support does not use MMIO primitives to access an
> MSC, but employs a shared-memory/doorbell based firmware protocol.
> Its complexity means that it must be able to handle errors, whereas we
> always assume an MMIO based MSC access succeeds today.
>
> Change the __mpam_read_reg() low level accessor function to return the
> requested data through a pointer, and return an error code instead.
> Also change the __mpam_write_reg() accessor function to return an error
> code. At the moment this is always 0, so all error handling paths are
> not exercised at the moment. This will change later when alternative
> MSC access methods like MPAM-Fb are activated.
>
> Change all direct users of those MSC wrappers to comply with the new
> prototypes, though the errors are not propagated all the way up yet.
>
> Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx>
> Reviewed-by: Jonathan Cameron <jonathan.cameron@xxxxxxxxxxxxxxxx>
> Reviewed-by: Ben Horgan <ben.horgan@xxxxxxx>
> ---
>   drivers/resctrl/mpam_devices.c | 208 +++++++++++++++++++++------------
>   1 file changed, 134 insertions(+), 74 deletions(-)
Reviewed-by: Gavin Shan <gshan@xxxxxxxxxx>