diff options
Diffstat (limited to 'src/cpu/x86')
| -rw-r--r-- | src/cpu/x86/smm/smm_stub.S | 31 |
1 files changed, 17 insertions, 14 deletions
diff --git a/src/cpu/x86/smm/smm_stub.S b/src/cpu/x86/smm/smm_stub.S index f479d62536..28b7d57635 100644 --- a/src/cpu/x86/smm/smm_stub.S +++ b/src/cpu/x86/smm/smm_stub.S @@ -98,28 +98,31 @@ smm_trampoline32: /* The CPU number is calculated by reading the initial APIC id. Since * the OS can maniuplate the APIC id use the non-changing cpuid result - * for APIC id (ax). A table is used to handle a discontiguous + * for APIC id (eax). A table is used to handle a discontiguous * APIC id space. */ apic_id: - mov $LAPIC_BASE_MSR, %ecx - rdmsr - andl $LAPIC_BASE_MSR_X2APIC_MODE, %eax - jz xapic + mov $LAPIC_BASE_MSR, %ecx + rdmsr + and $LAPIC_BASE_X2APIC_ENABLED, %eax + cmp $LAPIC_BASE_X2APIC_ENABLED, %eax + jne xapic x2apic: - mov $X2APIC_LAPIC_ID, %ecx - rdmsr - jmp apicid_end + mov $0xb, %eax + mov $0, %ecx + cpuid + mov %edx, %eax + jmp apicid_end xapic: - movl $(LOCAL_APIC_ADDR | LAPIC_ID), %esi - movl (%esi), %eax - shr $24, %eax + mov $1, %eax + cpuid + mov %ebx, %eax + shr $24, %eax apicid_end: - - mov $(apic_to_cpu_num), %ebx - xor %ecx, %ecx + mov $(apic_to_cpu_num), %ebx + xor %ecx, %ecx 1: cmp (%ebx, %ecx, 2), %ax |