powerpc/4xx: Simple platform for the ISS 4xx simulator

This is a trivial 4xx plaform that uses the new simple bsp from
Josh and is handy to use in simulators such as ISS or even Mambo
who don't properly implement most of the actual devices in the
SoC but really only the core.

Signed-off-by: Torez Smith  <lnxtorez@linux.vnet.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>

3 files changed, 179 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/44x/Kconfig b/arch/powerpc/platforms/44x/Kconfig
index 9365e530ac5..eeba0a70e46 100644
--- a/arch/powerpc/platforms/44x/Kconfig
+++ b/arch/powerpc/platforms/44x/Kconfig
@@ -160,6 +160,17 @@ config YOSEMITE
 	help
 	  This option enables support for the AMCC PPC440EP evaluation board.
 
+config ISS4xx
+	bool "ISS 4xx Simulator"
+	depends on (44x || 40x)
+	default n
+	select 405GP if 40x
+	select 440GP if 44x && !PPC_47x
+	select PPC_FPU
+	select OF_RTC
+	help
+	  This option enables support for the IBM ISS simulation environment
+
 #config LUAN
 #	bool "Luan"
 #	depends on 44x
diff --git a/arch/powerpc/platforms/44x/Makefile b/arch/powerpc/platforms/44x/Makefile
index ee6185aeaa3..82ff326e079 100644
--- a/arch/powerpc/platforms/44x/Makefile
+++ b/arch/powerpc/platforms/44x/Makefile
@@ -5,3 +5,4 @@ obj-$(CONFIG_SAM440EP) 	+= sam440ep.o
 obj-$(CONFIG_WARP)	+= warp.o
 obj-$(CONFIG_XILINX_VIRTEX_5_FXT) += virtex.o
 obj-$(CONFIG_XILINX_ML510) += virtex_ml510.o
+obj-$(CONFIG_ISS4xx)	+= iss4xx.o
diff --git a/arch/powerpc/platforms/44x/iss4xx.c b/arch/powerpc/platforms/44x/iss4xx.c
new file mode 100644
index 00000000000..aa46e9d1e77
--- /dev/null
+++ b/arch/powerpc/platforms/44x/iss4xx.c
@@ -0,0 +1,167 @@
+/*
+ * PPC476 board specific routines
+ *
+ * Copyright 2010 Torez Smith, IBM Corporation.
+ *
+ * Based on earlier code:
+ *    Matt Porter <mporter@kernel.crashing.org>
+ *    Copyright 2002-2005 MontaVista Software Inc.
+ *
+ *    Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
+ *    Copyright (c) 2003-2005 Zultys Technologies
+ *
+ *    Rewritten and ported to the merged powerpc tree:
+ *    Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/of_platform.h>
+#include <linux/rtc.h>
+
+#include <asm/machdep.h>
+#include <asm/prom.h>
+#include <asm/udbg.h>
+#include <asm/time.h>
+#include <asm/uic.h>
+#include <asm/ppc4xx.h>
+#include <asm/mpic.h>
+#include <asm/mmu.h>
+
+static __initdata struct of_device_id iss4xx_of_bus[] = {
+	{ .compatible = "ibm,plb4", },
+	{ .compatible = "ibm,plb6", },
+	{ .compatible = "ibm,opb", },
+	{ .compatible = "ibm,ebc", },
+	{},
+};
+
+static int __init iss4xx_device_probe(void)
+{
+	of_platform_bus_probe(NULL, iss4xx_of_bus, NULL);
+	of_instantiate_rtc();
+
+	return 0;
+}
+machine_device_initcall(iss4xx, iss4xx_device_probe);
+
+/* We can have either UICs or MPICs */
+static void __init iss4xx_init_irq(void)
+{
+	struct device_node *np;
+
+	/* Find top level interrupt controller */
+	for_each_node_with_property(np, "interrupt-controller") {
+		if (of_get_property(np, "interrupts", NULL) == NULL)
+			break;
+	}
+	if (np == NULL)
+		panic("Can't find top level interrupt controller");
+
+	/* Check type and do appropriate initialization */
+	if (of_device_is_compatible(np, "ibm,uic")) {
+		uic_init_tree();
+		ppc_md.get_irq = uic_get_irq;
+#ifdef CONFIG_MPIC
+	} else if (of_device_is_compatible(np, "chrp,open-pic")) {
+		/* The MPIC driver will get everything it needs from the
+		 * device-tree, just pass 0 to all arguments
+		 */
+		struct mpic *mpic = mpic_alloc(np, 0, MPIC_PRIMARY, 0, 0,
+					       " MPIC     ");
+		BUG_ON(mpic == NULL);
+		mpic_init(mpic);
+		ppc_md.get_irq = mpic_get_irq;
+#endif
+	} else
+		panic("Unrecognized top level interrupt controller");
+}
+
+#ifdef CONFIG_SMP
+static void __cpuinit smp_iss4xx_setup_cpu(int cpu)
+{
+	mpic_setup_this_cpu();
+}
+
+static void __cpuinit smp_iss4xx_kick_cpu(int cpu)
+{
+	struct device_node *cpunode = of_get_cpu_node(cpu, NULL);
+	const u64 *spin_table_addr_prop;
+	u32 *spin_table;
+	extern void start_secondary_47x(void);
+
+	BUG_ON(cpunode == NULL);
+
+	/* Assume spin table. We could test for the enable-method in
+	 * the device-tree but currently there's little point as it's
+	 * our only supported method
+	 */
+	spin_table_addr_prop = of_get_property(cpunode, "cpu-release-addr",
+					       NULL);
+	if (spin_table_addr_prop == NULL) {
+		pr_err("CPU%d: Can't start, missing cpu-release-addr !\n", cpu);
+		return;
+	}
+
+	/* Assume it's mapped as part of the linear mapping. This is a bit
+	 * fishy but will work fine for now
+	 */
+	spin_table = (u32 *)__va(*spin_table_addr_prop);
+	pr_debug("CPU%d: Spin table mapped at %p\n", cpu, spin_table);
+
+	spin_table[3] = cpu;
+	smp_wmb();
+	spin_table[1] = __pa(start_secondary_47x);
+	mb();
+}
+
+static struct smp_ops_t iss_smp_ops = {
+	.probe		= smp_mpic_probe,
+	.message_pass	= smp_mpic_message_pass,
+	.setup_cpu	= smp_iss4xx_setup_cpu,
+	.kick_cpu	= smp_iss4xx_kick_cpu,
+	.give_timebase	= smp_generic_give_timebase,
+	.take_timebase	= smp_generic_take_timebase,
+};
+
+static void __init iss4xx_smp_init(void)
+{
+	if (mmu_has_feature(MMU_FTR_TYPE_47x))
+		smp_ops = &iss_smp_ops;
+}
+
+#else /* CONFIG_SMP */
+static void __init iss4xx_smp_init(void) { }
+#endif /* CONFIG_SMP */
+
+static void __init iss4xx_setup_arch(void)
+{
+	iss4xx_smp_init();
+}
+
+/*
+ * Called very early, MMU is off, device-tree isn't unflattened
+ */
+static int __init iss4xx_probe(void)
+{
+	unsigned long root = of_get_flat_dt_root();
+
+	if (!of_flat_dt_is_compatible(root, "ibm,iss-4xx"))
+		return 0;
+
+	return 1;
+}
+
+define_machine(iss4xx) {
+	.name			= "ISS-4xx",
+	.probe			= iss4xx_probe,
+	.progress		= udbg_progress,
+	.init_IRQ		= iss4xx_init_irq,
+	.setup_arch		= iss4xx_setup_arch,
+	.restart		= ppc4xx_reset_system,
+	.calibrate_decr		= generic_calibrate_decr,
+};