From d127db1a23c94a876557b5bf8ca8bea49e8debb6 Mon Sep 17 00:00:00 2001 From: James Morse Date: Tue, 21 Nov 2023 13:44:51 +0000 Subject: 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 Reviewed-by: "Russell King (Oracle)" Reviewed-by: Shaoqin Huang Reviewed-by: Gavin Shan Signed-off-by: "Russell King (Oracle)" Reviewed-by: Jonathan Cameron Reviewed-by: Thomas Gleixner Link: https://lore.kernel.org/r/E1r5R3b-00Csza-Ku@rmk-PC.armlinux.org.uk Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/setup.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) (limited to 'arch/arm64/kernel/setup.c') 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) { -- cgit