Re: [PATCH 16/24] RISC-V: ACPI: clocksource/timer-riscv: Add ACPI support

From: Sunil V L
Date: Mon Feb 13 2023 - 12:39:39 EST


On Thu, Feb 09, 2023 at 08:58:25PM +0000, Conor Dooley wrote:
> On Mon, Jan 30, 2023 at 11:52:17PM +0530, Sunil V L wrote:
> > timer-riscv driver needs to get the timebase-frequency from
> > RISC-V Hart Capabilities Table (RHCT) on ACPI platforms. Add
> > support to read the information from RHCT.
> >
> > Signed-off-by: Sunil V L <sunilvl@xxxxxxxxxxxxxxxx>
> > ---
> > drivers/clocksource/timer-riscv.c | 9 +++++++++
> > 1 file changed, 9 insertions(+)
> >
> > diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
> > index 4016c065a01c..8079666753a6 100644
> > --- a/drivers/clocksource/timer-riscv.c
> > +++ b/drivers/clocksource/timer-riscv.c
> > @@ -10,6 +10,7 @@
> >
> > #define pr_fmt(fmt) "riscv-timer: " fmt
> >
> > +#include <linux/acpi.h>
> > #include <linux/clocksource.h>
> > #include <linux/clockchips.h>
> > #include <linux/cpu.h>
> > @@ -198,3 +199,11 @@ static int __init riscv_timer_init_dt(struct device_node *n)
> > }
> >
> > TIMER_OF_DECLARE(riscv_timer, "riscv", riscv_timer_init_dt);
> > +
> > +#ifdef CONFIG_ACPI
> > +static int __init riscv_timer_acpi_init(struct acpi_table_header *table)
> > +{
> > + return riscv_timer_init_common();
>
> I feel like I need to ask as it was deleted in the previous patch, how
> does ACPI determine whether the arch timer can wake the CPUs?
>
We have plans to add a flag in RHCT. But that still needs approval.

Thanks
Sunil