diff options
Diffstat (limited to 'arch/x86/include/asm/xen/hypervisor.h')
| -rw-r--r-- | arch/x86/include/asm/xen/hypervisor.h | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/x86/include/asm/xen/hypervisor.h b/arch/x86/include/asm/xen/hypervisor.h index 396ff4cc8ed4..66d0fff1ee84 100644 --- a/arch/x86/include/asm/xen/hypervisor.h +++ b/arch/x86/include/asm/xen/hypervisor.h @@ -37,4 +37,39 @@ extern struct shared_info *HYPERVISOR_shared_info; extern struct start_info *xen_start_info; +#include <asm/processor.h> + +static inline uint32_t xen_cpuid_base(void) +{ + uint32_t base, eax, ebx, ecx, edx; + char signature[13]; + + for (base = 0x40000000; base < 0x40010000; base += 0x100) { + cpuid(base, &eax, &ebx, &ecx, &edx); + *(uint32_t *)(signature + 0) = ebx; + *(uint32_t *)(signature + 4) = ecx; + *(uint32_t *)(signature + 8) = edx; + signature[12] = 0; + + if (!strcmp("XenVMMXenVMM", signature) && ((eax - base) >= 2)) + return base; + } + + return 0; +} + +#ifdef CONFIG_XEN +extern bool xen_hvm_need_lapic(void); + +static inline bool xen_x2apic_para_available(void) +{ + return xen_hvm_need_lapic(); +} +#else +static inline bool xen_x2apic_para_available(void) +{ + return (xen_cpuid_base() != 0); +} +#endif + #endif /* _ASM_X86_XEN_HYPERVISOR_H */ |