[kvm-unit-tests,v2,13/14] powerpc/ppc64: add RTAS support

diff --git a/lib/powerpc/asm/rtas.h b/lib/powerpc/asm/rtas.h
new file mode 100644
index 0000000000000..522225bcb6de3
--- /dev/null
+++ b/lib/powerpc/asm/rtas.h
@@ -0,0 +1,26 @@ 
+#ifndef _ASMPOWERPC_RTAS_H_
+#define _ASMPOWERPC_RTAS_H_
+/*
+ * Copyright (C) 2016, Red Hat Inc, Andrew Jones <drjones@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.
+ */
+#include <libcflat.h>
+
+#define RTAS_UNKNOWN_SERVICE	(-1)
+
+struct rtas_args {
+	u32 token;
+	u32 nargs;
+	u32 nret;
+	u32 args[16];
+	u32 *rets;
+};
+
+extern void rtas_init(void);
+extern int rtas_token(const char *service);
+extern int rtas_call(int token, int nargs, int nret, int *outputs, ...);
+
+extern void rtas_power_off(void);
+
+#endif /* _ASMPOWERPC_RTAS_H_ */
diff --git a/lib/powerpc/io.c b/lib/powerpc/io.c
index 5e1fa8dd96ab6..e57a28c583eb0 100644
--- a/lib/powerpc/io.c
+++ b/lib/powerpc/io.c
@@ -7,6 +7,7 @@ 
  */
 #include <libcflat.h>
 #include <asm/spinlock.h>
+#include <asm/rtas.h>
 
 extern void halt(int code);
 extern void putchar(int c);
@@ -15,6 +16,7 @@  static struct spinlock uart_lock;
 
 void io_init(void)
 {
+	rtas_init();
 }
 
 void puts(const char *s)
diff --git a/lib/powerpc/rtas.c b/lib/powerpc/rtas.c
new file mode 100644
index 0000000000000..7fcd667513087
--- /dev/null
+++ b/lib/powerpc/rtas.c
@@ -0,0 +1,120 @@ 
+/*
+ * powerpc RTAS
+ *
+ * Copyright (C) 2016, Red Hat Inc, Andrew Jones <drjones@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.
+ */
+#include <libcflat.h>
+#include <libfdt/libfdt.h>
+#include <devicetree.h>
+#include <asm/spinlock.h>
+#include <asm/io.h>
+#include <asm/rtas.h>
+
+#if defined(__powerpc64__)
+struct func_ptr {
+	unsigned long ptr;
+	unsigned long toc;
+};
+static struct func_ptr rtas_entry_funcptr;
+#endif
+typedef void (*rtas_entry_t)(unsigned long);
+static rtas_entry_t enter_rtas;
+static struct rtas_args rtas_args;
+static struct spinlock lock;
+
+static int rtas_node(void)
+{
+	int node = fdt_path_offset(dt_fdt(), "/rtas");
+
+	if (node < 0) {
+		printf("%s: /rtas: %s\n", __func__, fdt_strerror(node));
+		abort();
+	}
+
+	return node;
+}
+
+void rtas_init(void)
+{
+	const struct fdt_property *prop;
+	unsigned long entry;
+	u32 *data;
+	int len;
+
+	if (!dt_available()) {
+		printf("%s: No device tree!\n", __func__);
+		abort();
+	}
+
+	prop = fdt_get_property(dt_fdt(), rtas_node(),
+				"linux,rtas-entry", &len);
+	if (!prop) {
+		printf("%s: /rtas/linux,rtas-entry: %s\n",
+				__func__, fdt_strerror(len));
+		abort();
+	}
+
+	data = (u32 *)prop->data;
+	entry = (unsigned long)fdt32_to_cpu(*data);
+
+#if defined(__powerpc64__)
+	rtas_entry_funcptr.ptr = entry;
+	enter_rtas = (rtas_entry_t)&rtas_entry_funcptr;
+#else
+	enter_rtas = (rtas_entry_t)entry;
+#endif
+}
+
+int rtas_token(const char *service)
+{
+	const struct fdt_property *prop;
+	u32 *token;
+
+	prop = fdt_get_property(dt_fdt(), rtas_node(), service, NULL);
+	if (prop) {
+		token = (u32 *)prop->data;
+		return fdt32_to_cpu(*token);
+	}
+	return RTAS_UNKNOWN_SERVICE;
+}
+
+int rtas_call(int token, int nargs, int nret, int *outputs, ...)
+{
+	va_list list;
+	int ret, i;
+
+	spin_lock(&lock);
+
+	rtas_args.token = cpu_to_be32(token);
+	rtas_args.nargs = cpu_to_be32(nargs);
+	rtas_args.nret = cpu_to_be32(nret);
+	rtas_args.rets = &rtas_args.args[nargs];
+
+	va_start(list, outputs);
+	for (i = 0; i < nargs; ++i)
+		rtas_args.args[i] = cpu_to_be32(va_arg(list, u32));
+	va_end(list);
+
+	for (i = 0; i < nret; ++i)
+		rtas_args.rets[i] = 0;
+
+	enter_rtas(__pa(&rtas_args));
+
+	if (nret > 1 && outputs != NULL)
+		for (i = 0; i < nret - 1; ++i)
+			outputs[i] = be32_to_cpu(rtas_args.rets[i + 1]);
+
+	ret = nret > 0 ? be32_to_cpu(rtas_args.rets[0]) : 0;
+
+	spin_unlock(&lock);
+	return ret;
+}
+
+void rtas_power_off(void)
+{
+	printf("RTAS power-off returned %d\n",
+		rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
+	assert(0);
+}
diff --git a/lib/ppc64/asm/rtas.h b/lib/ppc64/asm/rtas.h
new file mode 100644
index 0000000000000..fe77f635cd860
--- /dev/null
+++ b/lib/ppc64/asm/rtas.h
@@ -0,0 +1 @@ 
+#include "../../powerpc/asm/rtas.h"
diff --git a/powerpc/Makefile.common b/powerpc/Makefile.common
index 074f5672356b1..27b2bcad74865 100644
--- a/powerpc/Makefile.common
+++ b/powerpc/Makefile.common
@@ -34,6 +34,7 @@  cflatobjs += lib/powerpc/io.o
 cflatobjs += lib/powerpc/setup.o
 cflatobjs += lib/powerpc/mmu.o
 cflatobjs += lib/powerpc/smp.o
+cflatobjs += lib/powerpc/rtas.o
 
 libgcc := $(shell $(CC) $(machine) --print-libgcc-file-name)
 start_addr := $(shell printf "%x\n" $$(( $(phys_base) + $(kernel_offset) )))