[PATCH v3 2/3] x86: devicetree: enable multiprocessing in DT

From: Ivan Gorinov
Date: Thu Mar 01 2018 - 18:14:14 EST


Adding code to register the processors described in Device Tree.
APIC ID is specified in 'intel-apic_id' propery as used in U-Boot.
First address specified in 'reg' is used as default APIC ID.

Signed-off-by: Ivan Gorinov <ivan.gorinov@xxxxxxxxx>
---
arch/x86/kernel/devicetree.c | 26 ++++++++++++++++++++++++--
1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
index 44189ee..ef1cd85 100644
--- a/arch/x86/kernel/devicetree.c
+++ b/arch/x86/kernel/devicetree.c
@@ -130,6 +130,29 @@ static void __init dtb_setup_hpet(void)
#endif
}

+static void __init dtb_cpu_setup(void)
+{
+ struct device_node *dn;
+ struct resource r;
+ const void *prop;
+ int apic_id, version;
+ int ret;
+
+ version = GET_APIC_VERSION(apic_read(APIC_LVR));
+ for_each_node_by_type(dn, "cpu") {
+ prop = of_get_property(dn, "intel,apic-id", NULL);
+ if (prop) {
+ apic_id = be32_to_cpup(prop);
+ } else {
+ ret = of_address_to_resource(dn, 0, &r);
+ if (WARN_ON_ONCE(ret))
+ continue;
+ apic_id = r.start;
+ }
+ generic_processor_info(apic_id, version);
+ }
+}
+
static void __init dtb_lapic_setup(void)
{
#ifdef CONFIG_X86_LOCAL_APIC
@@ -153,8 +176,6 @@ static void __init dtb_lapic_setup(void)
smp_found_config = 1;
pic_mode = 1;
register_lapic_address(r.start);
- generic_processor_info(boot_cpu_physical_apicid,
- GET_APIC_VERSION(apic_read(APIC_LVR)));
#endif
}

@@ -256,6 +277,7 @@ static void __init dtb_ioapic_setup(void) {}
static void __init dtb_apic_setup(void)
{
dtb_lapic_setup();
+ dtb_cpu_setup();
dtb_ioapic_setup();
}

--
2.7.4