1 files changed, 22 insertions, 9 deletions
diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h
index 439f6b5d31f6..c5f89442785c 100644
--- a/arch/arm64/include/asm/virt.h
+++ b/arch/arm64/include/asm/virt.h
@@ -19,25 +19,38 @@
 #define __ASM__VIRT_H
 
 /*
- * The arm64 hcall implementation uses x0 to specify the hcall type. A value
- * less than 0xfff indicates a special hcall, such as get/set vector.
- * Any other value is used as a pointer to the function to call.
+ * The arm64 hcall implementation uses x0 to specify the hcall
+ * number. A value less than HVC_STUB_HCALL_NR indicates a special
+ * hcall, such as set vector. Any other value is handled in a
+ * hypervisor specific way.
+ *
+ * The hypercall is allowed to clobber any of the caller-saved
+ * registers (x0-x18), so it is advisable to use it through the
+ * indirection of a function call (as implemented in hyp-stub.S).
  */
 
-/* HVC_GET_VECTORS - Return the value of the vbar_el2 register. */
-#define HVC_GET_VECTORS 0
-
 /*
  * HVC_SET_VECTORS - Set the value of the vbar_el2 register.
  *
  * @x1: Physical address of the new vector table.
  */
-#define HVC_SET_VECTORS 1
+#define HVC_SET_VECTORS 0
 
 /*
  * HVC_SOFT_RESTART - CPU soft reset, used by the cpu_soft_restart routine.
  */
-#define HVC_SOFT_RESTART 2
+#define HVC_SOFT_RESTART 1
+
+/*
+ * HVC_RESET_VECTORS - Restore the vectors to the original HYP stubs
+ */
+#define HVC_RESET_VECTORS 2
+
+/* Max number of HYP stub hypercalls */
+#define HVC_STUB_HCALL_NR 3
+
+/* Error returned when an invalid stub number is passed into x0 */
+#define HVC_STUB_ERR	0xbadca11
 
 #define BOOT_CPU_MODE_EL1	(0xe11)
 #define BOOT_CPU_MODE_EL2	(0xe12)
@@ -61,7 +74,7 @@
 extern u32 __boot_cpu_mode[2];
 
 void __hyp_set_vectors(phys_addr_t phys_vector_base);
-phys_addr_t __hyp_get_vectors(void);
+void __hyp_reset_vectors(void);
 
 /* Reports the availability of HYP mode */
 static inline bool is_hyp_mode_available(void)