[tip:x86/paravirt] xen: Switch to use hypervisor_cpuid_base()

[tip-bot for Jason Wang <tipbot@zytor.com>]

Commit-ID:  448ac44d561f0aba5baac54bac62fe40d07230b6
Gitweb:     http://git.kernel.org/tip/448ac44d561f0aba5baac54bac62fe40d07230b6
Author:     Jason Wang <jasowang@redhat.com>
AuthorDate: Thu, 25 Jul 2013 16:54:33 +0800
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Mon, 5 Aug 2013 06:34:09 -0700

xen: Switch to use hypervisor_cpuid_base()

Switch to use hypervisor_cpuid_base() to detect Xen.

Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: http://lkml.kernel.org/r/1374742475-2485-2-git-send-email-jasowang@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/include/asm/xen/hypervisor.h | 16 +---------------
 1 file changed, 1 insertion(+), 15 deletions(-)

diff --git a/arch/x86/include/asm/xen/hypervisor.h b/arch/x86/include/asm/xen/hypervisor.h
index 125f344..d866959 100644
--- a/arch/x86/include/asm/xen/hypervisor.h
+++ b/arch/x86/include/asm/xen/hypervisor.h
@@ -40,21 +40,7 @@ extern struct start_info *xen_start_info;
 
 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;
+	return hypervisor_cpuid_base("XenVMMXenVMM", 2);
 }
 
 #ifdef CONFIG_XEN