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> | 2023-12-11 09:43:12 +0000 |
| commit | 339a65179abaef6ab8bf84ebe15d6e7036946d5c (patch) | |
| tree | 23b62d0ec814b48b09f5a02dd65e20426f586d4d | |
| parent | 631ca19da4c6687a4c88d56378c1ecba48916206 (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.
In the next patch, we will use arch_cpu_is_hotpluggable().
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Shaoqin Huang <shahuang@redhat.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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 7b071a00425d..84bce830e365 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 f3034099fd95..b1e43f56ee46 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) { |