From d9b8ca8474fd4fdd43ba6d97a4fee8b49b978067 Mon Sep 17 00:00:00 2001 From: Sheng Yang Date: Tue, 21 Dec 2010 14:18:49 +0800 Subject: xen: HVM X2APIC support This patch is similiar to Gleb Natapov's patch for KVM, which enable the hypervisor to emulate x2apic feature for the guest. By this way, the emulation of lapic would be simpler with x2apic interface(MSR), and faster. [v2: Re-organized 'xen_hvm_need_lapic' per Ian Campbell suggestion] Acked-by: Jeremy Fitzhardinge Signed-off-by: Sheng Yang Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/include/asm/xen/hypervisor.h | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) (limited to 'arch/x86/include/asm/xen/hypervisor.h') 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 + +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 */ -- cgit v1.2.3-59-g8ed1b