MIPS: Add functions for hypervisor call

Introduce kvm_hypercall[0-3].
Define three new hypercalls for MIPS: GET_CLOCK_FREQ, EXIT_VM, and
CONSOLE_OUTPUT.

[andreas.herrmann:
* Properly define hypercalls and HC numbers for MIPS
in kvm_para.h header files]

Signed-off-by: David Daney <[e-mail]>
Signed-off-by: Andreas Herrmann <[e-mail]>
Cc: [e-mail]
Cc: James Hogan <[e-mail]>
Cc: [e-mail]
Patchwork: https://patchwork.linux-mips.org/patch/7005/
Signed-off-by: Ralf Baechle <[e-mail]>

arch/mips/include/asm/kvm_para.h

···
+#ifndef _ASM_MIPS_KVM_PARA_H
+#define _ASM_MIPS_KVM_PARA_H
+
+#include <uapi/asm/kvm_para.h>
+
+#define KVM_HYPERCALL ".word 0x42000028"
+
+/*
+ * Hypercalls for KVM.
+ *
+ * Hypercall number is passed in v0.
+ * Return value will be placed in v0.
+ * Up to 3 arguments are passed in a0, a1, and a2.
+ */
+static inline unsigned long kvm_hypercall0(unsigned long num)
+{
+	register unsigned long n asm("v0");
+	register unsigned long r asm("v0");
+
+	n = num;
+	__asm__ __volatile__(
+		KVM_HYPERCALL
+		: "=r" (r) : "r" (n) : "memory"
+		);
+
+	return r;
+}
+
+static inline unsigned long kvm_hypercall1(unsigned long num,
+					unsigned long arg0)
+{
+	register unsigned long n asm("v0");
+	register unsigned long r asm("v0");
+	register unsigned long a0 asm("a0");
+
+	n = num;
+	a0 = arg0;
+	__asm__ __volatile__(
+		KVM_HYPERCALL
+		: "=r" (r) : "r" (n), "r" (a0) : "memory"
+		);
+
+	return r;
+}
+
+static inline unsigned long kvm_hypercall2(unsigned long num,
+					unsigned long arg0, unsigned long arg1)
+{
+	register unsigned long n asm("v0");
+	register unsigned long r asm("v0");
+	register unsigned long a0 asm("a0");
+	register unsigned long a1 asm("a1");
+
+	n = num;
+	a0 = arg0;
+	a1 = arg1;
+	__asm__ __volatile__(
+		KVM_HYPERCALL
+		: "=r" (r) : "r" (n), "r" (a0), "r" (a1) : "memory"
+		);
+
+	return r;
+}
+
+static inline unsigned long kvm_hypercall3(unsigned long num,
+	unsigned long arg0, unsigned long arg1, unsigned long arg2)
+{
+	register unsigned long n asm("v0");
+	register unsigned long r asm("v0");
+	register unsigned long a0 asm("a0");
+	register unsigned long a1 asm("a1");
+	register unsigned long a2 asm("a2");
+
+	n = num;
+	a0 = arg0;
+	a1 = arg1;
+	a2 = arg2;
+	__asm__ __volatile__(
+		KVM_HYPERCALL
+		: "=r" (r) : "r" (n), "r" (a0), "r" (a1), "r" (a2) : "memory"
+		);
+
+	return r;
+}
+
+static inline bool kvm_check_and_clear_guest_paused(void)
+{
+	return false;
+}
+
+static inline unsigned int kvm_arch_para_features(void)
+{
+	return 0;
+}
+
+#ifdef CONFIG_MIPS_PARAVIRT
+static inline bool kvm_para_available(void)
+{
+	return true;
+}
+#else
+static inline bool kvm_para_available(void)
+{
+	return false;
+}
+#endif
+
+
+#endif /* _ASM_MIPS_KVM_PARA_H */

arch/mips/include/uapi/asm/kvm_para.h

···
-#include <asm-generic/kvm_para.h>
+#ifndef _UAPI_ASM_MIPS_KVM_PARA_H
+#define _UAPI_ASM_MIPS_KVM_PARA_H
+
+
+#endif /* _UAPI_ASM_MIPS_KVM_PARA_H */

include/uapi/linux/kvm_para.h

···
 #define KVM_HC_FEATURES			3
 #define KVM_HC_PPC_MAP_MAGIC_PAGE	4
 #define KVM_HC_KICK_CPU			5
+#define KVM_HC_MIPS_GET_CLOCK_FREQ	6
+#define KVM_HC_MIPS_EXIT_VM		7
+#define KVM_HC_MIPS_CONSOLE_OUTPUT	8
 
 /*
  * hypercalls use architecture specific