| Message ID | 20180425233121.13270-5-jeremy.linton@arm.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | None | expand |
Hi, On 04/26/2018 05:27 AM, Sudeep Holla wrote: > > > On 26/04/18 00:31, Jeremy Linton wrote: >> Its helpful to be able to lookup the acpi_processor_id associated >> with a logical cpu. Provide an arm64 helper to do this. >> > > As I pointed out in the earlier version, this patch is not required. > The acpi_id stored in the acpi_processor can be used for this. > Won't the below change make it work ? I can't think of any reason why it > shouldn't. So, I only noticed your previous email last night on the mail archive, as I was applying your review/ack tags and couldn't find a response for this patch, seem the spam/etc filters need some further tweaking! At that point, I was pretty sure the suggestion wasn't going to work out of the box as a lot of this code is running fairly early in the boot process. I spent a bit of time and plugged the change in to verify that assertion, and yes the per_cpu processor/acpi bits aren't setup early enough to be used by much of this code. It is being called from init_cpu_topology()/smp_prepare_cpus() which precedes do_basic_setup/do_initcalls() which is what runs the acpi_init() sequence which ends up eventually allocating the required data structures. So without restructuring the core boot sequence, this seems like a reasonable solution. Thanks, > > Regards, > Sudeep > > -->8 > > diff --git i/drivers/acpi/pptt.c w/drivers/acpi/pptt.c > index 0fc4b2654665..f421f58b4ae6 100644 > --- i/drivers/acpi/pptt.c > +++ w/drivers/acpi/pptt.c > @@ -432,7 +432,7 @@ static void cache_setup_acpi_cpu(struct > acpi_table_header *table, > { > struct acpi_pptt_cache *found_cache; > struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); > - u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); > + u32 acpi_cpu_id = per_cpu(processors, cpu)->acpi_id; > struct cacheinfo *this_leaf; > unsigned int index = 0; > struct acpi_pptt_processor *cpu_node = NULL; >
diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index 32f465a80e4e..0db62a4cbce2 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -86,6 +86,10 @@ static inline bool acpi_has_cpu_in_madt(void) } struct acpi_madt_generic_interrupt *acpi_cpu_get_madt_gicc(int cpu); +static inline u32 get_acpi_id_for_cpu(unsigned int cpu) +{ + return acpi_cpu_get_madt_gicc(cpu)->uid; +} static inline void arch_fix_phys_package_id(int num, u32 slot) { } void __init acpi_init_cpus(void);
Its helpful to be able to lookup the acpi_processor_id associated with a logical cpu. Provide an arm64 helper to do this. Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> --- arch/arm64/include/asm/acpi.h | 4 ++++ 1 file changed, 4 insertions(+) -- 2.13.6