Re: [PATCH v4 1/2] dt-bindings: timer: thead,c900-aclint-mtimer: separate mtime and mtimecmp regs

From: Anup Patel
Date: Thu Nov 30 2023 - 07:25:05 EST


On Thu, Nov 30, 2023 at 5:40 PM Conor Dooley <conor@xxxxxxxxxx> wrote:
>
> On Thu, Nov 30, 2023 at 05:18:15PM +0530, Anup Patel wrote:
> > On Thu, Nov 30, 2023 at 5:15 PM Conor Dooley <conor@xxxxxxxxxx> wrote:
>
> > > > and add separate "riscv" prefixed DT binding for RISC-V mtimer.
> > >
> > > Do you know of any users for a "riscv,mtimer" binding that are not
> > > covered by existing bindings for the clint?
> >
> > Ventana Veyron-v1 implements a mtimer per-cluster (or chiplet)
> > which is compatible to "riscv,mtimer" (i.e. we have both mtime
> > and mtimecmp MMIO registers).
>
> Okay, thanks. I guess iff veyron-v1 DT support shows up (or other
> similar devices) we can go ahead with a "riscv,mtimer" binding then.
> I had thought that you guys were going to be using ACPI though, so
> I guess the "other similar devices" applies.

We use ACPI from EDK2 onwards in our boot-flow. The booting
stages prior to EDK2 (such as OpenSBI) use DT. In fact, EDK2
also uses information in DT to populate static parts of the ACPI
table.

Regards,
Anup