arch/loongarch/Kconfig | 6 ++-- arch/loongarch/include/asm/acpi.h | 2 +- arch/loongarch/include/asm/loongarch.h | 4 +-- arch/loongarch/kernel/acpi.c | 41 ++++++++++++++++++++++---- 4 files changed, 41 insertions(+), 12 deletions(-)
Increase max supported CPUs up to 2048, including:
1. Increase CSR.CPUID register's effective width;
2. Define MAX_CORE_PIC (a.k.a. max physical ID) to 2048;
3. Allow NR_CPUS (a.k.a. max logical ID) to be as large as 2048;
4. Introduce acpi_numa_x2apic_affinity_init() to handle ACPI SRAT
for CPUID >= 256.
Note: The reason of increasing to 2048 rather than 4096/8192 is because
the IPI hardware can only support 2048 as a maximum.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---
arch/loongarch/Kconfig | 6 ++--
arch/loongarch/include/asm/acpi.h | 2 +-
arch/loongarch/include/asm/loongarch.h | 4 +--
arch/loongarch/kernel/acpi.c | 41 ++++++++++++++++++++++----
4 files changed, 41 insertions(+), 12 deletions(-)
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 38706186cf13..0c356de91bc4 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -496,10 +496,10 @@ config HOTPLUG_CPU
Say N if you want to disable CPU hotplug.
config NR_CPUS
- int "Maximum number of CPUs (2-256)"
- range 2 256
+ int "Maximum number of CPUs (2-2048)"
+ range 2 2048
+ default "2048"
depends on SMP
- default "64"
help
This allows you to specify the maximum number of CPUs which this
kernel will support.
diff --git a/arch/loongarch/include/asm/acpi.h b/arch/loongarch/include/asm/acpi.h
index 313f66f7913a..7376840fa9f7 100644
--- a/arch/loongarch/include/asm/acpi.h
+++ b/arch/loongarch/include/asm/acpi.h
@@ -33,7 +33,7 @@ static inline bool acpi_has_cpu_in_madt(void)
return true;
}
-#define MAX_CORE_PIC 256
+#define MAX_CORE_PIC 2048
extern struct list_head acpi_wakeup_device_list;
extern struct acpi_madt_core_pic acpi_core_pic[MAX_CORE_PIC];
diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h
index 52651aa0e583..d84dac88a584 100644
--- a/arch/loongarch/include/asm/loongarch.h
+++ b/arch/loongarch/include/asm/loongarch.h
@@ -411,8 +411,8 @@
/* Config CSR registers */
#define LOONGARCH_CSR_CPUID 0x20 /* CPU core id */
-#define CSR_CPUID_COREID_WIDTH 9
-#define CSR_CPUID_COREID _ULCAST_(0x1ff)
+#define CSR_CPUID_COREID_WIDTH 11
+#define CSR_CPUID_COREID _ULCAST_(0x7ff)
#define LOONGARCH_CSR_PRCFG1 0x21 /* Config1 */
#define CSR_CONF1_VSMAX_SHIFT 12
diff --git a/arch/loongarch/kernel/acpi.c b/arch/loongarch/kernel/acpi.c
index 1120ac2824f6..fba4bb93e1bd 100644
--- a/arch/loongarch/kernel/acpi.c
+++ b/arch/loongarch/kernel/acpi.c
@@ -244,11 +244,6 @@ void __init acpi_boot_table_init(void)
#ifdef CONFIG_ACPI_NUMA
-static __init int setup_node(int pxm)
-{
- return acpi_map_pxm_to_node(pxm);
-}
-
void __init numa_set_distance(int from, int to, int distance)
{
if ((u8)distance != distance || (from == to && distance != LOCAL_DISTANCE)) {
@@ -280,7 +275,41 @@ acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa)
pxm |= (pa->proximity_domain_hi[1] << 16);
pxm |= (pa->proximity_domain_hi[2] << 24);
}
- node = setup_node(pxm);
+ node = acpi_map_pxm_to_node(pxm);
+ if (node < 0) {
+ pr_err("SRAT: Too many proximity domains %x\n", pxm);
+ bad_srat();
+ return;
+ }
+
+ if (pa->apic_id >= CONFIG_NR_CPUS) {
+ pr_info("SRAT: PXM %u -> CPU 0x%02x -> Node %u skipped apicid that is too big\n",
+ pxm, pa->apic_id, node);
+ return;
+ }
+
+ early_numa_add_cpu(pa->apic_id, node);
+
+ set_cpuid_to_node(pa->apic_id, node);
+ node_set(node, numa_nodes_parsed);
+ pr_info("SRAT: PXM %u -> CPU 0x%02x -> Node %u\n", pxm, pa->apic_id, node);
+}
+
+void __init
+acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa)
+{
+ int pxm, node;
+
+ if (srat_disabled())
+ return;
+ if (pa->header.length < sizeof(struct acpi_srat_x2apic_cpu_affinity)) {
+ bad_srat();
+ return;
+ }
+ if ((pa->flags & ACPI_SRAT_CPU_ENABLED) == 0)
+ return;
+ pxm = pa->proximity_domain;
+ node = acpi_map_pxm_to_node(pxm);
if (node < 0) {
pr_err("SRAT: Too many proximity domains %x\n", pxm);
bad_srat();
--
2.47.1在 5/7/25 3:34 PM, Huacai Chen 写道: > Increase max supported CPUs up to 2048, including: > 1. Increase CSR.CPUID register's effective width; > 2. Define MAX_CORE_PIC (a.k.a. max physical ID) to 2048; > 3. Allow NR_CPUS (a.k.a. max logical ID) to be as large as 2048; > 4. Introduce acpi_numa_x2apic_affinity_init() to handle ACPI SRAT > for CPUID >= 256. > > Note: The reason of increasing to 2048 rather than 4096/8192 is because > the IPI hardware can only support 2048 as a maximum. > > Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> > --- > arch/loongarch/Kconfig | 6 ++-- > arch/loongarch/include/asm/acpi.h | 2 +- > arch/loongarch/include/asm/loongarch.h | 4 +-- > arch/loongarch/kernel/acpi.c | 41 ++++++++++++++++++++++---- > 4 files changed, 41 insertions(+), 12 deletions(-) > > diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig > index 38706186cf13..0c356de91bc4 100644 > --- a/arch/loongarch/Kconfig > +++ b/arch/loongarch/Kconfig > @@ -496,10 +496,10 @@ config HOTPLUG_CPU > Say N if you want to disable CPU hotplug. > > config NR_CPUS > - int "Maximum number of CPUs (2-256)" > - range 2 256 > + int "Maximum number of CPUs (2-2048)" > + range 2 2048 > + default "2048" I'm curious. As a new architecture, why did you write such a small value at the beginning? Reviewed-by: Yanteng Si <si.yanteng@linux.dev> Thanks, Yanteng
On Wed, May 7, 2025 at 6:07 PM Yanteng Si <si.yanteng@linux.dev> wrote: > > 在 5/7/25 3:34 PM, Huacai Chen 写道: > > Increase max supported CPUs up to 2048, including: > > 1. Increase CSR.CPUID register's effective width; > > 2. Define MAX_CORE_PIC (a.k.a. max physical ID) to 2048; > > 3. Allow NR_CPUS (a.k.a. max logical ID) to be as large as 2048; > > 4. Introduce acpi_numa_x2apic_affinity_init() to handle ACPI SRAT > > for CPUID >= 256. > > > > Note: The reason of increasing to 2048 rather than 4096/8192 is because > > the IPI hardware can only support 2048 as a maximum. > > > > Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> > > --- > > arch/loongarch/Kconfig | 6 ++-- > > arch/loongarch/include/asm/acpi.h | 2 +- > > arch/loongarch/include/asm/loongarch.h | 4 +-- > > arch/loongarch/kernel/acpi.c | 41 ++++++++++++++++++++++---- > > 4 files changed, 41 insertions(+), 12 deletions(-) > > > > diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig > > index 38706186cf13..0c356de91bc4 100644 > > --- a/arch/loongarch/Kconfig > > +++ b/arch/loongarch/Kconfig > > @@ -496,10 +496,10 @@ config HOTPLUG_CPU > > Say N if you want to disable CPU hotplug. > > > > > config NR_CPUS > > - int "Maximum number of CPUs (2-256)" > > - range 2 256 > > + int "Maximum number of CPUs (2-2048)" > > + range 2 2048 > > + default "2048" > I'm curious. As a new architecture, why did you write > such a small value at the beginning? Good question. Just because there are many limits at the beginning, hardware register, irqchips, acpi tables, and so on. Huacai > > > Reviewed-by: Yanteng Si <si.yanteng@linux.dev> > > Thanks, > Yanteng >
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