From: jbeulich@novell.com
Subject: make /proc/cpuinfo track CPU speed
Patch-mainline: obsolete

--- head.orig/arch/x86/kernel/acpi/processor_extcntl_xen.c	2012-04-11 17:03:00.000000000 +0200
+++ head/arch/x86/kernel/acpi/processor_extcntl_xen.c	2012-04-11 17:05:41.000000000 +0200
@@ -27,7 +27,7 @@
 #include <linux/acpi.h>
 #include <linux/pm.h>
 #include <linux/cpu.h>
-
+#include <linux/export.h>
 #include <linux/cpufreq.h>
 #include <acpi/processor.h>
 #include <asm/hypercall.h>
@@ -280,3 +280,22 @@ static int __init init_extcntl(void)
 	return 0;
 }
 arch_initcall(init_extcntl);
+
+unsigned int cpufreq_quick_get(unsigned int cpu)
+{
+	xen_platform_op_t op;
+
+	op.cmd = XENPF_get_cpu_freq;
+	op.u.get_cpu_freq.vcpu = cpu;
+	return HYPERVISOR_platform_op(&op) == 0 ? op.u.get_cpu_freq.freq : 0;
+}
+
+unsigned int cpufreq_quick_get_max(unsigned int cpu)
+{
+	xen_platform_op_t op;
+
+	op.cmd = XENPF_get_cpu_freq_max;
+	op.u.get_cpu_freq.vcpu = cpu;
+	return HYPERVISOR_platform_op(&op) == 0 ? op.u.get_cpu_freq.freq : 0;
+}
+EXPORT_SYMBOL(cpufreq_quick_get_max);
--- head.orig/include/linux/cpufreq.h	2012-04-10 14:24:30.000000000 +0200
+++ head/include/linux/cpufreq.h	2012-04-11 17:05:49.000000000 +0200
@@ -323,7 +323,7 @@ static inline unsigned int cpufreq_get(u
 #endif
 
 /* query the last known CPU freq (in kHz). If zero, cpufreq couldn't detect it */
-#ifdef CONFIG_CPU_FREQ
+#if defined(CONFIG_CPU_FREQ) || defined(CONFIG_PROCESSOR_EXTERNAL_CONTROL)
 unsigned int cpufreq_quick_get(unsigned int cpu);
 unsigned int cpufreq_quick_get_max(unsigned int cpu);
 #else
--- head.orig/include/xen/interface/platform.h	2011-11-17 17:36:32.000000000 +0100
+++ head/include/xen/interface/platform.h	2012-04-04 13:36:46.000000000 +0200
@@ -513,6 +513,16 @@ struct xenpf_core_parking {
 typedef struct xenpf_core_parking xenpf_core_parking_t;
 DEFINE_XEN_GUEST_HANDLE(xenpf_core_parking_t);
 
+#define XENPF_get_cpu_freq        ('N' << 24)
+#define XENPF_get_cpu_freq_min    (XENPF_get_cpu_freq + 1)
+#define XENPF_get_cpu_freq_max    (XENPF_get_cpu_freq_min + 1)
+struct xenpf_get_cpu_freq {
+    /* IN variables */
+    uint32_t vcpu;
+    /* OUT variables */
+    uint32_t freq; /* in kHz */
+};
+
 struct xen_platform_op {
 	uint32_t cmd;
 	uint32_t interface_version; /* XENPF_INTERFACE_VERSION */
@@ -535,6 +545,7 @@ struct xen_platform_op {
 		struct xenpf_cpu_hotadd        cpu_add;
 		struct xenpf_mem_hotadd        mem_add;
 		struct xenpf_core_parking      core_parking;
+		struct xenpf_get_cpu_freq      get_cpu_freq;
 		uint8_t                        pad[128];
 	} u;
 };