Re: [PATCH v3 41/47] arm_mpam: Generate a configuration for min controls

Jonathan Cameron
2026-01-13T15:39:44Z

On Mon, 12 Jan 2026 16:59:08 +0000
Ben Horgan <ben.horgan@arm.com> wrote:

> From: James Morse <james.morse@arm.com>
>
> MPAM supports a minimum and maximum control for memory bandwidth. The
> purpose of the minimum control is to give priority to tasks that are below
> their minimum value. Resctrl only provides one value for the bandwidth
> configuration, which is used for the maximum.
>
> The minimum control is always programmed to zero on hardware that supports
> it.
>
> Generate a minimum bandwidth value that is 5% lower than the value provided
> by resctrl. This means tasks that are not receiving their target bandwidth
> can be prioritised by the hardware.
>
> For component reset reuse the same calculation so that the default is a
> value resctrl can set.
>
> CC: Zeng Heng <zengheng4@huawei.com>
> Signed-off-by: James Morse <james.morse@arm.com>
> Signed-off-by: Ben Horgan <ben.horgan@arm.com>

I'm interested to see how this plays out as a default choice
vs what people elect to run. Seems harmless to start with this.

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>