Re: [PATCH v15 6/8] cxl/mem: Configure dynamic capacity interrupts
From: Alison Schofield
Date: Wed Oct 07 2026 - 19:46:58 EST
On Wed, Oct 07, 2026 at 01:16:39PM -0700, Anisa Su wrote:
> From: Ira Weiny <iweiny@xxxxxxxxxx>
>
> Dynamic Capacity Devices (DCD) support extent change notifications
> through the event log mechanism. The interrupt mailbox commands were
> extended in CXL 3.1 to support these notifications. Firmware can't
> configure DCD events to be FW controlled but can retain control of
> memory events.
>
> Configure DCD event log interrupts on devices supporting dynamic
> capacity. Disable DCD if interrupts are not supported.
>
> The DCD event log is not drained here. cxl_event_drain_mask() reports
> only the logs the driver can service, and the DCD bit is added by
> the patch introducing DCD event handling. Until then a DCD interrupt
> wakes the event thread, which finds no log it owns and returns.
>
> Care is taken to preserve the interrupt policy set by the FW if FW first
> has been selected by the BIOS.
>
> Based on an original patch by Navneet Singh.
>
> Signed-off-by: Ira Weiny <iweiny@xxxxxxxxxx>
> Co-developed-by: Anisa Su <anisa.su@xxxxxxxxxxx>
> Signed-off-by: Anisa Su <anisa.su@xxxxxxxxxxx>
Reviewed-by: Alison Schofield <alison.schofield@xxxxxxxxx>