Messages in this thread Patch in this message | | | Date | Tue, 30 Apr 2024 14:26:06 +1000 | Subject | Re: [PATCH v8 05/16] ACPI: processor: Add acpi_get_processor_handle() helper | From | Gavin Shan <> |
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On 4/26/24 23:51, Jonathan Cameron wrote: > If CONFIG_ACPI_PROCESSOR provide a helper to retrieve the > acpi_handle for a given CPU allowing access to methods > in DSDT. > > Tested-by: Miguel Luis <miguel.luis@oracle.com> > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > --- > v8: Code simplification suggested by Rafael. > Fixup ;; spotted by Gavin > --- > drivers/acpi/acpi_processor.c | 11 +++++++++++ > include/linux/acpi.h | 7 +++++++ > 2 files changed, 18 insertions(+) >
Reviewed-by: Gavin Shan <gshan@redhat.com>
> diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c > index 3b180e21f325..ecc2721fecae 100644 > --- a/drivers/acpi/acpi_processor.c > +++ b/drivers/acpi/acpi_processor.c > @@ -35,6 +35,17 @@ EXPORT_PER_CPU_SYMBOL(processors); > struct acpi_processor_errata errata __read_mostly; > EXPORT_SYMBOL_GPL(errata); > > +acpi_handle acpi_get_processor_handle(int cpu) > +{ > + struct acpi_processor *pr; > + > + pr = per_cpu(processors, cpu); > + if (pr) > + return pr->handle; > + > + return NULL; > +} > +
Maybe it's worthy to have more check here, something like below. However, it's also fine without the extra check.
if (cpu >= nr_cpu_ids || !cpu_possible(cpu)) return NULL;
> static int acpi_processor_errata_piix4(struct pci_dev *dev) > { > u8 value1 = 0; > diff --git a/include/linux/acpi.h b/include/linux/acpi.h > index 34829f2c517a..9844a3f9c4e5 100644 > --- a/include/linux/acpi.h > +++ b/include/linux/acpi.h > @@ -309,6 +309,8 @@ int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 acpi_id, > int acpi_unmap_cpu(int cpu); > #endif /* CONFIG_ACPI_HOTPLUG_CPU */ > > +acpi_handle acpi_get_processor_handle(int cpu); > + > #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC > int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr); > #endif > @@ -1077,6 +1079,11 @@ static inline bool acpi_sleep_state_supported(u8 sleep_state) > return false; > } > > +static inline acpi_handle acpi_get_processor_handle(int cpu) > +{ > + return NULL; > +} > + > #endif /* !CONFIG_ACPI */ > > extern void arch_post_acpi_subsys_init(void);
Thanks, Gavin
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