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arm64: Kconfig: Enable hotplug CPU on arm64 if ACPI_PROCESSOR is enabled.

In order to move arch_register_cpu() to be called via the same path
for initially present CPUs described by ACPI and hotplugged CPUs
ACPI_HOTPLUG_CPU needs to be enabled.

The protection against invalid IDs in acpi_map_cpu() is needed as
at least one production BIOS is in the wild which reports entries
in DSDT (with no _STA method, so assumed enabled and present)
that don't match MADT.

Tested-by: Miguel Luis <miguel.luis@oracle.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20240529133446.28446-18-Jonathan.Cameron@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Jonathan Cameron 2024-05-29 14:34:44 +01:00 committed by Catalin Marinas
parent eba4675008
commit 9d0873892f
2 changed files with 23 additions and 0 deletions

View File

@ -5,6 +5,7 @@ config ARM64
select ACPI_CCA_REQUIRED if ACPI
select ACPI_GENERIC_GSI if ACPI
select ACPI_GTDT if ACPI
select ACPI_HOTPLUG_CPU if ACPI_PROCESSOR
select ACPI_IORT if ACPI
select ACPI_REDUCED_HARDWARE_ONLY if ACPI
select ACPI_MCFG if (ACPI && PCI)

View File

@ -30,6 +30,7 @@
#include <linux/pgtable.h>
#include <acpi/ghes.h>
#include <acpi/processor.h>
#include <asm/cputype.h>
#include <asm/cpu_ops.h>
#include <asm/daifflags.h>
@ -423,6 +424,27 @@ void arch_reserve_mem_area(acpi_physical_address addr, size_t size)
memblock_mark_nomap(addr, size);
}
#ifdef CONFIG_ACPI_HOTPLUG_CPU
int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 apci_id,
int *pcpu)
{
/* If an error code is passed in this stub can't fix it */
if (*pcpu < 0) {
pr_warn_once("Unable to map CPU to valid ID\n");
return *pcpu;
}
return 0;
}
EXPORT_SYMBOL(acpi_map_cpu);
int acpi_unmap_cpu(int cpu)
{
return 0;
}
EXPORT_SYMBOL(acpi_unmap_cpu);
#endif /* CONFIG_ACPI_HOTPLUG_CPU */
#ifdef CONFIG_ACPI_FFH
/*
* Implements ARM64 specific callbacks to support ACPI FFH Operation Region as