Re: [PATCH v2 10/45] arm64: mpam: Add cpu_pm notifier to restore MPAM sysregs

[Jonathan Cameron]

On Fri, 19 Dec 2025 18:11:12 +0000
Ben Horgan <ben.horgan@xxxxxxx> wrote:

> From: James Morse <james.morse@xxxxxxx>
> 
> The MPAM system registers will be lost if the CPU is reset during PSCI's
> CPU_SUSPEND.
> 
> Add a PM notifier to restore them.
> 
> mpam_thread_switch(current) can't be used as this won't make any changes if
> the in-memory copy says the register already has the correct value. In
> reality the system register is UNKNOWN out of reset.
> 
> Signed-off-by: James Morse <james.morse@xxxxxxx>
> Signed-off-by: Ben Horgan <ben.horgan@xxxxxxx>
Reviewed-by: Jonathan Cameron <jonathan.cameron@xxxxxxxxxx>