m68k/atari: Initial ARAnyM support

Add improved support for running under the ARAnyM emulator
(Atari Running on Any Machine - http://aranym.org/).

[michael, geert: Cleanups and updates]

Signed-off-by: Petr Stehlik <pstehlik@sophics.cz>
Signed-off-by: Michael Schmitz <schmitz@debian.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

2 files changed, 121 insertions, 0 deletions

diff --git a/arch/m68k/emu/Makefile b/arch/m68k/emu/Makefile
new file mode 100644
index 000000000000..34cfa348ca2b
--- /dev/null
+++ b/arch/m68k/emu/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for Linux arch/m68k/emu source directory
+#
+
+obj-y			+= natfeat.o
diff --git a/arch/m68k/emu/natfeat.c b/arch/m68k/emu/natfeat.c
new file mode 100644
index 000000000000..987d77322178
--- /dev/null
+++ b/arch/m68k/emu/natfeat.c
@@ -0,0 +1,116 @@
+/*
+ * natfeat.c - ARAnyM hardware support via Native Features (natfeats)
+ *
+ * Copyright (c) 2005 Petr Stehlik of ARAnyM dev team
+ *
+ * Reworked for Linux by Roman Zippel <zippel@linux-m68k.org>
+ *
+ * This software may be used and distributed according to the terms of
+ * the GNU General Public License (GPL), incorporated herein by reference.
+ */
+
+#include <linux/types.h>
+#include <linux/console.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <asm/machdep.h>
+#include <asm/natfeat.h>
+
+asm("\n"
+"	.global nf_get_id,nf_call\n"
+"nf_get_id:\n"
+"	.short	0x7300\n"
+"	rts\n"
+"nf_call:\n"
+"	.short	0x7301\n"
+"	rts\n"
+"1:	moveq.l	#0,%d0\n"
+"	rts\n"
+"	.section __ex_table,\"a\"\n"
+"	.long	nf_get_id,1b\n"
+"	.long	nf_call,1b\n"
+"	.previous");
+EXPORT_SYMBOL_GPL(nf_get_id);
+EXPORT_SYMBOL_GPL(nf_call);
+
+static int stderr_id;
+
+static void nf_write(struct console *co, const char *str, unsigned int count)
+{
+	char buf[68];
+
+	buf[64] = 0;
+	while (count > 64) {
+		memcpy(buf, str, 64);
+		nf_call(stderr_id, buf);
+		str += 64;
+		count -= 64;
+	}
+	memcpy(buf, str, count);
+	buf[count] = 0;
+	nf_call(stderr_id, buf);
+}
+
+void nfprint(const char *fmt, ...)
+{
+	static char buf[256];
+	va_list ap;
+	int n;
+
+	va_start(ap, fmt);
+	n = vsnprintf(buf, 256, fmt, ap);
+	nf_call(nf_get_id("NF_STDERR"), buf);
+	va_end(ap);
+}
+
+static struct console nf_console_driver = {
+	.name	= "debug",
+	.write	= nf_write,
+	.flags	= CON_PRINTBUFFER,
+	.index	= -1,
+};
+
+static int __init nf_debug_setup(char *arg)
+{
+	if (strcmp(arg, "emu"))
+		return 0;
+
+	stderr_id = nf_get_id("NF_STDERR");
+	if (stderr_id)
+		register_console(&nf_console_driver);
+	return 0;
+}
+
+early_param("debug", nf_debug_setup);
+
+static void nf_poweroff(void)
+{
+	long id = nf_get_id("NF_SHUTDOWN");
+
+	if (id)
+		nf_call(id);
+}
+
+void nf_init(void)
+{
+	unsigned long id, version;
+	char buf[256];
+
+	id = nf_get_id("NF_VERSION");
+	if (!id)
+		return;
+	version = nf_call(id);
+
+	id = nf_get_id("NF_NAME");
+	if (!id)
+		return;
+	nf_call(id, buf, 256);
+	buf[255] = 0;
+
+	pr_info("NatFeats found (%s, %lu.%lu)\n", buf, version >> 16,
+		version & 0xffff);
+
+	mach_power_off = nf_poweroff;
+}