diff options
| author | James Morse <james.morse@arm.com> | 2021-03-29 13:48:38 +0100 |
|---|---|---|
| committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2023-10-23 10:05:35 +0100 |
| commit | ad7ca47c457ca06064591688759c8bf5600b36b6 (patch) | |
| tree | 8a57bd308d374398eed11cb44e53a64dc1f5f0a2 | |
| parent | bd23876a347fbdd39ec57d13bd6d8a5561b18405 (diff) | |
arm64: setup: Switch over to GENERIC_CPU_DEVICES using arch_register_cpu()
To allow ACPI's _STA value to hide CPUs that are present, but not
available to online right now due to VMM or firmware policy, the
register_cpu() call needs to be made by the ACPI machinery when ACPI
is in use. This allows it to hide CPUs that are unavailable from sysfs.
Switching to GENERIC_CPU_DEVICES is an intermediate step to allow all
five ACPI architectures to be modified at once.
Switch over to GENERIC_CPU_DEVICES, and provide an arch_register_cpu()
that populates the hotpluggable flag. arch_register_cpu() is also the
interface the ACPI machinery expects.
The struct cpu in struct cpuinfo_arm64 is never used directly, remove
it to use the one GENERIC_CPU_DEVICES provides.
This changes the CPUs visible in sysfs from possible to present, but
on arm64 smp_prepare_cpus() ensures these are the same.
This patch also has the effect of moving the registration of CPUs from
subsys to driver core initialisation, prior to any initcalls running.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
Changes since RFC v2:
* Add note about initialisation order change.
| -rw-r--r-- | arch/arm64/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm64/include/asm/cpu.h | 1 | ||||
| -rw-r--r-- | arch/arm64/kernel/setup.c | 13 |
3 files changed, 5 insertions, 10 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 78f20e632712..4042cd6fc6b2 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -132,6 +132,7 @@ config ARM64 select GENERIC_ARCH_TOPOLOGY select GENERIC_CLOCKEVENTS_BROADCAST select GENERIC_CPU_AUTOPROBE + select GENERIC_CPU_DEVICES select GENERIC_CPU_VULNERABILITIES select GENERIC_EARLY_IOREMAP select GENERIC_IDLE_POLL_SETUP diff --git a/arch/arm64/include/asm/cpu.h b/arch/arm64/include/asm/cpu.h index e749838b9c5d..887bd0d992bb 100644 --- a/arch/arm64/include/asm/cpu.h +++ b/arch/arm64/include/asm/cpu.h @@ -38,7 +38,6 @@ struct cpuinfo_32bit { }; struct cpuinfo_arm64 { - struct cpu cpu; struct kobject kobj; u64 reg_ctr; u64 reg_cntfrq; diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 417a8a86b2db..165bd2c0dd5a 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -402,19 +402,14 @@ static inline bool cpu_can_disable(unsigned int cpu) return false; } -static int __init topology_init(void) +int arch_register_cpu(int num) { - int i; + struct cpu *cpu = &per_cpu(cpu_devices, num); - for_each_possible_cpu(i) { - struct cpu *cpu = &per_cpu(cpu_data.cpu, i); - cpu->hotpluggable = cpu_can_disable(i); - register_cpu(cpu, i); - } + cpu->hotpluggable = cpu_can_disable(num); - return 0; + return register_cpu(cpu, num); } -subsys_initcall(topology_init); static void dump_kernel_offset(void) { |