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[RFC 2/9] drivers/perf: riscv: Add a flag to indicate SBI v2.0 support

Atish Patra posted 9 patches 2 years, 2 months ago
There is a newer version of this series
[RFC 2/9] drivers/perf: riscv: Add a flag to indicate SBI v2.0 support
Posted by Atish Patra 2 years, 2 months ago 
SBI v2.0 added few functions to improve SBI PMU extension. In order
to be backward compatible, the driver must use these functions only
if SBI v2.0 is available.

Signed-off-by: Atish Patra <atishp@rivosinc.com>
---
 drivers/perf/riscv_pmu_sbi.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index 16acd4dcdb96..40a335350d08 100644
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -35,6 +35,8 @@
 PMU_FORMAT_ATTR(event, "config:0-47");
 PMU_FORMAT_ATTR(firmware, "config:63");
 
+static bool sbi_v2_available;
+
 static struct attribute *riscv_arch_formats_attr[] = {
 	&format_attr_event.attr,
 	&format_attr_firmware.attr,
@@ -1108,6 +1110,9 @@ static int __init pmu_sbi_devinit(void)
 		return 0;
 	}
 
+	if (sbi_spec_version >= sbi_mk_version(2, 0))
+		sbi_v2_available = true;
+
 	ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_RISCV_STARTING,
 				      "perf/riscv/pmu:starting",
 				      pmu_sbi_starting_cpu, pmu_sbi_dying_cpu);
-- 
2.34.1
Re: [RFC 2/9] drivers/perf: riscv: Add a flag to indicate SBI v2.0 support
Posted by Conor Dooley 2 years, 2 months ago 
On Mon, Dec 04, 2023 at 06:43:03PM -0800, Atish Patra wrote:
> SBI v2.0 added few functions to improve SBI PMU extension. In order
> to be backward compatible, the driver must use these functions only
> if SBI v2.0 is available.
> 
> Signed-off-by: Atish Patra <atishp@rivosinc.com>

IMO this does not make sense in a patch of its own and should probably
be squashed with the first user for it.

> ---
>  drivers/perf/riscv_pmu_sbi.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
> index 16acd4dcdb96..40a335350d08 100644
> --- a/drivers/perf/riscv_pmu_sbi.c
> +++ b/drivers/perf/riscv_pmu_sbi.c
> @@ -35,6 +35,8 @@
>  PMU_FORMAT_ATTR(event, "config:0-47");
>  PMU_FORMAT_ATTR(firmware, "config:63");
>  
> +static bool sbi_v2_available;
> +
>  static struct attribute *riscv_arch_formats_attr[] = {
>  	&format_attr_event.attr,
>  	&format_attr_firmware.attr,
> @@ -1108,6 +1110,9 @@ static int __init pmu_sbi_devinit(void)
>  		return 0;
>  	}
>  
> +	if (sbi_spec_version >= sbi_mk_version(2, 0))
> +		sbi_v2_available = true;
> +
>  	ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_RISCV_STARTING,
>  				      "perf/riscv/pmu:starting",
>  				      pmu_sbi_starting_cpu, pmu_sbi_dying_cpu);
> -- 
> 2.34.1
>
Re: [RFC 2/9] drivers/perf: riscv: Add a flag to indicate SBI v2.0 support
Posted by Anup Patel 2 years, 1 month ago 
On Thu, Dec 7, 2023 at 5:39 PM Conor Dooley <conor.dooley@microchip.com> wrote:
>
> On Mon, Dec 04, 2023 at 06:43:03PM -0800, Atish Patra wrote:
> > SBI v2.0 added few functions to improve SBI PMU extension. In order
> > to be backward compatible, the driver must use these functions only
> > if SBI v2.0 is available.
> >
> > Signed-off-by: Atish Patra <atishp@rivosinc.com>
>
> IMO this does not make sense in a patch of its own and should probably
> be squashed with the first user for it.

I agree. This patch should be squashed into patch4 where the
flag is first used.

Regards,
Anup

>
> > ---
> >  drivers/perf/riscv_pmu_sbi.c | 5 +++++
> >  1 file changed, 5 insertions(+)
> >
> > diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
> > index 16acd4dcdb96..40a335350d08 100644
> > --- a/drivers/perf/riscv_pmu_sbi.c
> > +++ b/drivers/perf/riscv_pmu_sbi.c
> > @@ -35,6 +35,8 @@
> >  PMU_FORMAT_ATTR(event, "config:0-47");
> >  PMU_FORMAT_ATTR(firmware, "config:63");
> >
> > +static bool sbi_v2_available;
> > +
> >  static struct attribute *riscv_arch_formats_attr[] = {
> >       &format_attr_event.attr,
> >       &format_attr_firmware.attr,
> > @@ -1108,6 +1110,9 @@ static int __init pmu_sbi_devinit(void)
> >               return 0;
> >       }
> >
> > +     if (sbi_spec_version >= sbi_mk_version(2, 0))
> > +             sbi_v2_available = true;
> > +
> >       ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_RISCV_STARTING,
> >                                     "perf/riscv/pmu:starting",
> >                                     pmu_sbi_starting_cpu, pmu_sbi_dying_cpu);
> > --
> > 2.34.1
> >
Re: [RFC 2/9] drivers/perf: riscv: Add a flag to indicate SBI v2.0 support
Posted by Atish Kumar Patra 2 years, 1 month ago 
On Thu, Dec 14, 2023 at 4:16 AM Anup Patel <anup@brainfault.org> wrote:
>
> On Thu, Dec 7, 2023 at 5:39 PM Conor Dooley <conor.dooley@microchip.com> wrote:
> >
> > On Mon, Dec 04, 2023 at 06:43:03PM -0800, Atish Patra wrote:
> > > SBI v2.0 added few functions to improve SBI PMU extension. In order
> > > to be backward compatible, the driver must use these functions only
> > > if SBI v2.0 is available.
> > >
> > > Signed-off-by: Atish Patra <atishp@rivosinc.com>
> >
> > IMO this does not make sense in a patch of its own and should probably
> > be squashed with the first user for it.
>
> I agree. This patch should be squashed into patch4 where the
> flag is first used.
>

Done. Thanks.


> Regards,
> Anup
>
> >
> > > ---
> > >  drivers/perf/riscv_pmu_sbi.c | 5 +++++
> > >  1 file changed, 5 insertions(+)
> > >
> > > diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
> > > index 16acd4dcdb96..40a335350d08 100644
> > > --- a/drivers/perf/riscv_pmu_sbi.c
> > > +++ b/drivers/perf/riscv_pmu_sbi.c
> > > @@ -35,6 +35,8 @@
> > >  PMU_FORMAT_ATTR(event, "config:0-47");
> > >  PMU_FORMAT_ATTR(firmware, "config:63");
> > >
> > > +static bool sbi_v2_available;
> > > +
> > >  static struct attribute *riscv_arch_formats_attr[] = {
> > >       &format_attr_event.attr,
> > >       &format_attr_firmware.attr,
> > > @@ -1108,6 +1110,9 @@ static int __init pmu_sbi_devinit(void)
> > >               return 0;
> > >       }
> > >
> > > +     if (sbi_spec_version >= sbi_mk_version(2, 0))
> > > +             sbi_v2_available = true;
> > > +
> > >       ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_RISCV_STARTING,
> > >                                     "perf/riscv/pmu:starting",
> > >                                     pmu_sbi_starting_cpu, pmu_sbi_dying_cpu);
> > > --
> > > 2.34.1
> > >

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