arm/arm64: add some PSCI API

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

config/config-arm-common.mak

@@ -35,6 +35,7 @@ cflatobjs += lib/arm/io.o
 cflatobjs += lib/arm/setup.o
 cflatobjs += lib/arm/mmu.o
 cflatobjs += lib/arm/bitops.o
+cflatobjs += lib/arm/psci.o
 
 libeabi = lib/arm/libeabi.a
 eabiobjs = lib/arm/eabi_compat.o

lib/arm/asm/psci.h

+#ifndef _ASMARM_PSCI_H_
+#define _ASMARM_PSCI_H_
+#include <libcflat.h>
+#include <asm/uapi-psci.h>
+
+#define PSCI_INVOKE_ARG_TYPE	u32
+#define PSCI_FN_CPU_ON		PSCI_0_2_FN_CPU_ON
+
+extern int psci_invoke(u32 function_id, u32 arg0, u32 arg1, u32 arg2);
+extern int psci_cpu_on(unsigned long cpuid, unsigned long entry_point);
+extern void psci_sys_reset(void);
+
+#endif /* _ASMARM_PSCI_H_ */

lib/arm/psci.c

+/*
+ * PSCI API
+ * From arch/arm[64]/kernel/psci.c
+ *
+ * Copyright (C) 2015, Red Hat Inc, Andrew Jones <drjones@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.
+ */
+#include <asm/psci.h>
+
+#define T PSCI_INVOKE_ARG_TYPE
+__attribute__((noinline))
+int psci_invoke(T function_id, T arg0, T arg1, T arg2)
+{
+	asm volatile(
+		"hvc #0"
+	: "+r" (function_id)
+	: "r" (arg0), "r" (arg1), "r" (arg2));
+	return function_id;
+}
+
+int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
+{
+	return psci_invoke(PSCI_FN_CPU_ON, cpuid, entry_point, 0);
+}
+
+void psci_sys_reset(void)
+{
+	psci_invoke(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
+}

lib/arm64/asm/psci.h

+#ifndef _ASMARM64_PSCI_H_
+#define _ASMARM64_PSCI_H_
+#include <libcflat.h>
+#include <asm/uapi-psci.h>
+
+#define PSCI_INVOKE_ARG_TYPE	u64
+#define PSCI_FN_CPU_ON		PSCI_0_2_FN64_CPU_ON
+
+extern int psci_invoke(u64 function_id, u64 arg0, u64 arg1, u64 arg2);
+extern int psci_cpu_on(unsigned long cpuid, unsigned long entry_point);
+extern void psci_sys_reset(void);
+
+#endif /* _ASMARM64_PSCI_H_ */