[patch 7/8] powerpc: hvc backend for systemsim

[Arnd Bergmann]

The IBM full system simulator for PowerPC has its own
set of calls used for console interaction, when not
simulating actual serial port hardware.

This is needed to run the simulator for Cell and can
also be used for the PowerPC 970 simulator.

It also adds the generic asm/systemsim.h header file
that is also used by other device drivers for the
system simulator, i.e. the block and network drivers.

Signed-off-by: "Ryan S. Arnold" <rsa at us.ibm.com>
Signed-off-by: Arnd Bergmann <arndb at de.ibm.com>

Index: linux-2.6.16-rc/drivers/char/hvc_fss.c
===================================================================
--- /dev/null
+++ linux-2.6.16-rc/drivers/char/hvc_fss.c
@@ -0,0 +1,109 @@
+/*
+ * IBM Full System Simulator driver interface to hvc_console.c
+ *
+ * (C) Copyright IBM Corporation 2001-2005
+ * Author(s): Maximino Augilar <IBM STI Design Center>
+ *          : Ryan S. Arnold <rsa at us.ibm.com>
+ *
+ *    inspired by drivers/char/hvc_console.c
+ *    written by Anton Blanchard and Paul Mackerras
+ *
+ * Some code is from the IBM Full System Simulator Group in ARL.
+ * Author: Patrick Bohrer <IBM Austin Research Lab>
+ *
+ * Much of this code was moved here from the IBM Full System Simulator
+ * Bogus console driver in order to reuse the framework provided by the hvc
+ * console driver. Ryan S. Arnold <rsa at us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/console.h>
+
+#include <asm/prom.h>
+#include <asm/irq.h>
+#include <asm/systemsim.h>
+
+#include "hvc_console.h"
+
+#define SIM_WRITE_CONSOLE_CODE 0
+#define SIM_READ_CONSOLE_CODE 60
+
+#define hvc_fss_cookie 0x1aa70e29
+
+static int hvc_fss_write_console(uint32_t vtermno, const char *buf, int count)
+{
+	int ret;
+	ret = callthru3(SIM_WRITE_CONSOLE_CODE, (unsigned long)buf, count, 1);
+	if (ret != 0)
+		return (count - ret); /* is this right? */
+
+	/* the calling routine expects to receive the number of bytes sent */
+	return count;
+}
+
+static int hvc_fss_read_console(uint32_t vtermno, char *buf, int count)
+{
+	unsigned long got;
+	int c, i;
+
+	got = 0;
+	for (i = 0; i < count; i++) {
+		if ((c = callthru0(SIM_READ_CONSOLE_CODE)) != -1) {
+			buf[i] = c;
+			++got;
+		}
+		else
+			break;
+	}
+	return got;
+}
+
+static struct hv_ops hvc_fss_get_put_ops = {
+	.get_chars = hvc_fss_read_console,
+	.put_chars = hvc_fss_write_console,
+};
+
+static int __init hvc_fss_init(void)
+{
+	struct hvc_struct *hp;
+
+	/* Allocate an hvc_struct for the console device we instantiated
+	 * earlier.  Save off hp so that we can return it on exit */
+	hp = hvc_alloc(hvc_fss_cookie, NO_IRQ, &hvc_fss_get_put_ops);
+	if (IS_ERR(hp))
+		return PTR_ERR(hp);
+
+	return 0;
+}
+module_init(hvc_fss_init);
+
+/* This will happen prior to module init.  There is no tty at this time? */
+static int __init hvc_fss_console_init(void)
+{
+	/* Don't register if we aren't running on the simulator */
+	if (of_find_node_by_path("/mambo")) {
+		/* Tell the driver we know of one console device.  We
+		 * shouldn't get a collision on the index as long as no-one
+		 * else instantiates on hardware they don't have. */
+		hvc_instantiate(hvc_fss_cookie, 0, &hvc_fss_get_put_ops );
+		add_preferred_console("hvc", 0, NULL);
+	}
+	return 0;
+}
+console_initcall(hvc_fss_console_init);
Index: linux-2.6.16-rc/drivers/char/Kconfig
===================================================================
--- linux-2.6.16-rc.orig/drivers/char/Kconfig
+++ linux-2.6.16-rc/drivers/char/Kconfig
@@ -578,6 +578,14 @@ config HVC_CONSOLE
 	  console. This driver allows each pSeries partition to have a console
 	  which is accessed via the HMC.
 
+config HVC_FSS
+	bool "IBM Full System Simulator Console support"
+	depends on PPC_SYSTEMSIM
+	select HVC_DRIVER
+	help
+	  IBM Full System Simulator Console device driver which makes use of
+	  the HVC_DRIVER front end.
+
 config HVCS
 	tristate "IBM Hypervisor Virtual Console Server support"
 	depends on PPC_PSERIES
Index: linux-2.6.16-rc/drivers/char/Makefile
===================================================================
--- linux-2.6.16-rc.orig/drivers/char/Makefile
+++ linux-2.6.16-rc/drivers/char/Makefile
@@ -43,6 +43,7 @@ obj-$(CONFIG_SX)		+= sx.o generic_serial
 obj-$(CONFIG_RIO)		+= rio/ generic_serial.o
 obj-$(CONFIG_HVC_DRIVER)	+= hvc_console.o
 obj-$(CONFIG_HVC_CONSOLE)	+= hvc_vio.o hvsi.o
+obj-$(CONFIG_HVC_FSS)		+= hvc_fss.o
 obj-$(CONFIG_RAW_DRIVER)	+= raw.o
 obj-$(CONFIG_SGI_SNSC)		+= snsc.o snsc_event.o
 obj-$(CONFIG_MMTIMER)		+= mmtimer.o

--