Add hypercall for guest to get CPU frequency

diff --git a/palacios/include/palacios/vmm_hypercall.h b/palacios/include/palacios/vmm_hypercall.h
index 8a7fc5d..a7c79f2 100644 (file)
--- a/palacios/include/palacios/vmm_hypercall.h
+++ b/palacios/include/palacios/vmm_hypercall.h
@@ -50,7 +50,8 @@ typedef enum {
     TELEMETRY_HCALL =      0x3001,         // no args
     BALLOON_START_HCALL =  0xba00,         // RAX: size
     BALLOON_QUERY_HCALL =  0xba01,         // RCX: req_pgs(out), RDX: alloc_pgs(out)
-    OS_DEBUG_HCALL =       0xc0c0          // RBX: msg_gpa, RCX: msg_len, RDX: buf_is_va (flag)
+    OS_DEBUG_HCALL =       0xc0c0,          // RBX: msg_gpa, RCX: msg_len, RDX: buf_is_va (flag)
+    TIME_CPUFREQ_HCALL   =  0xd000       //RCX: cpu freq (out)
 } hcall_id_t;
 
 

diff --git a/palacios/src/palacios/vmm_time.c b/palacios/src/palacios/vmm_time.c
index 44d5d02..b169669 100644 (file)
--- a/palacios/src/palacios/vmm_time.c
+++ b/palacios/src/palacios/vmm_time.c
@@ -21,6 +21,18 @@
 #include <palacios/vmm.h>
 #include <palacios/vm_guest.h>
 
+static int handle_cpufreq_hcall(struct guest_info * info, uint_t hcall_id, void * priv_data) {
+    struct vm_time * time_state = &(info->time_state);
+
+    info->vm_regs.rbx = time_state->cpu_freq;
+
+    PrintDebug("Guest request cpu frequency: return %ld\n", (long)info->vm_regs.rbx);
+    
+    return 0;
+}
+
+
+
 void v3_init_time(struct guest_info * info) {
     struct vm_time * time_state = &(info->time_state);
 
@@ -32,6 +44,8 @@ void v3_init_time(struct guest_info * info) {
   
     INIT_LIST_HEAD(&(time_state->timers));
     time_state->num_timers = 0;
+
+    v3_register_hypercall(info->vm_info, TIME_CPUFREQ_HCALL, handle_cpufreq_hcall, NULL);
 }