Re: [PATCH 24/33] arm_mpam: Probe and reset the rest of the features

Gavin Shan
2025-11-09T23:01:29Z

On 11/7/25 10:34 PM, Ben Horgan wrote:
> From: James Morse <james.morse@arm.com>
>
> MPAM supports more features than are going to be exposed to resctrl.
> For partid other than 0, the reset values of these controls isn't
> known.
>
> Discover the rest of the features so they can be reset to avoid any
> side effects when resctrl is in use.
>
> PARTID narrowing allows MSC/RIS to support less configuration space than
> is usable. If this feature is found on a class of device we are likely
> to use, then reduce the partid_max to make it usable. This allows us
> to map a PARTID to itself.
>
> CC: Rohit Mathew <Rohit.Mathew@arm.com>
> CC: Zeng Heng <zengheng4@huawei.com>
> CC: Dave Martin <Dave.Martin@arm.com>
> Signed-off-by: James Morse <james.morse@arm.com>
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> Tested-by: Fenghua Yu <fenghuay@nvidia.com>
> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
> Tested-by: Peter Newman <peternewman@google.com>
> Signed-off-by: Ben Horgan <ben.horgan@arm.com>
> ---
> Changes since v3:
> enum order and commas
> ---
> drivers/resctrl/mpam_devices.c | 188 ++++++++++++++++++++++++++++++++
> drivers/resctrl/mpam_internal.h | 18 +++
> 2 files changed, 206 insertions(+)
>
Reviewed-by: Gavin Shan <gshan@redhat.com>