1/*
2 * PPC476 board specific routines
3 *
4 * Copyright 2010 Torez Smith, IBM Corporation.
5 *
6 * Based on earlier code:
7 *    Matt Porter <mporter@kernel.crashing.org>
8 *    Copyright 2002-2005 MontaVista Software Inc.
9 *
10 *    Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
11 *    Copyright (c) 2003-2005 Zultys Technologies
12 *
13 *    Rewritten and ported to the merged powerpc tree:
14 *    Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
15 *
16 * This program is free software; you can redistribute  it and/or modify it
17 * under  the terms of  the GNU General  Public License as published by the
18 * Free Software Foundation;  either version 2 of the  License, or (at your
19 * option) any later version.
20 */
21
22#include <linux/init.h>
23#include <linux/of_platform.h>
24#include <linux/rtc.h>
25
26#include <asm/machdep.h>
27#include <asm/prom.h>
28#include <asm/udbg.h>
29#include <asm/time.h>
30#include <asm/uic.h>
31#include <asm/ppc4xx.h>
32#include <asm/mpic.h>
33#include <asm/mmu.h>
34
35static const struct of_device_id iss4xx_of_bus[] __initconst = {
36	{ .compatible = "ibm,plb4", },
37	{ .compatible = "ibm,plb6", },
38	{ .compatible = "ibm,opb", },
39	{ .compatible = "ibm,ebc", },
40	{},
41};
42
43static int __init iss4xx_device_probe(void)
44{
45	of_platform_bus_probe(NULL, iss4xx_of_bus, NULL);
46	of_instantiate_rtc();
47
48	return 0;
49}
50machine_device_initcall(iss4xx, iss4xx_device_probe);
51
52/* We can have either UICs or MPICs */
53static void __init iss4xx_init_irq(void)
54{
55	struct device_node *np;
56
57	/* Find top level interrupt controller */
58	for_each_node_with_property(np, "interrupt-controller") {
59		if (of_get_property(np, "interrupts", NULL) == NULL)
60			break;
61	}
62	if (np == NULL)
63		panic("Can't find top level interrupt controller");
64
65	/* Check type and do appropriate initialization */
66	if (of_device_is_compatible(np, "ibm,uic")) {
67		uic_init_tree();
68		ppc_md.get_irq = uic_get_irq;
69#ifdef CONFIG_MPIC
70	} else if (of_device_is_compatible(np, "chrp,open-pic")) {
71		/* The MPIC driver will get everything it needs from the
72		 * device-tree, just pass 0 to all arguments
73		 */
74		struct mpic *mpic = mpic_alloc(np, 0, MPIC_NO_RESET, 0, 0, " MPIC     ");
75		BUG_ON(mpic == NULL);
76		mpic_init(mpic);
77		ppc_md.get_irq = mpic_get_irq;
78#endif
79	} else
80		panic("Unrecognized top level interrupt controller");
81}
82
83#ifdef CONFIG_SMP
84static void smp_iss4xx_setup_cpu(int cpu)
85{
86	mpic_setup_this_cpu();
87}
88
89static int smp_iss4xx_kick_cpu(int cpu)
90{
91	struct device_node *cpunode = of_get_cpu_node(cpu, NULL);
92	const u64 *spin_table_addr_prop;
93	u32 *spin_table;
94	extern void start_secondary_47x(void);
95
96	BUG_ON(cpunode == NULL);
97
98	/* Assume spin table. We could test for the enable-method in
99	 * the device-tree but currently there's little point as it's
100	 * our only supported method
101	 */
102	spin_table_addr_prop = of_get_property(cpunode, "cpu-release-addr",
103					       NULL);
104	if (spin_table_addr_prop == NULL) {
105		pr_err("CPU%d: Can't start, missing cpu-release-addr !\n", cpu);
106		return -ENOENT;
107	}
108
109	/* Assume it's mapped as part of the linear mapping. This is a bit
110	 * fishy but will work fine for now
111	 */
112	spin_table = (u32 *)__va(*spin_table_addr_prop);
113	pr_debug("CPU%d: Spin table mapped at %p\n", cpu, spin_table);
114
115	spin_table[3] = cpu;
116	smp_wmb();
117	spin_table[1] = __pa(start_secondary_47x);
118	mb();
119
120	return 0;
121}
122
123static struct smp_ops_t iss_smp_ops = {
124	.probe		= smp_mpic_probe,
125	.message_pass	= smp_mpic_message_pass,
126	.setup_cpu	= smp_iss4xx_setup_cpu,
127	.kick_cpu	= smp_iss4xx_kick_cpu,
128	.give_timebase	= smp_generic_give_timebase,
129	.take_timebase	= smp_generic_take_timebase,
130};
131
132static void __init iss4xx_smp_init(void)
133{
134	if (mmu_has_feature(MMU_FTR_TYPE_47x))
135		smp_ops = &iss_smp_ops;
136}
137
138#else /* CONFIG_SMP */
139static void __init iss4xx_smp_init(void) { }
140#endif /* CONFIG_SMP */
141
142static void __init iss4xx_setup_arch(void)
143{
144	iss4xx_smp_init();
145}
146
147/*
148 * Called very early, MMU is off, device-tree isn't unflattened
149 */
150static int __init iss4xx_probe(void)
151{
152	unsigned long root = of_get_flat_dt_root();
153
154	if (!of_flat_dt_is_compatible(root, "ibm,iss-4xx"))
155		return 0;
156
157	return 1;
158}
159
160define_machine(iss4xx) {
161	.name			= "ISS-4xx",
162	.probe			= iss4xx_probe,
163	.progress		= udbg_progress,
164	.init_IRQ		= iss4xx_init_irq,
165	.setup_arch		= iss4xx_setup_arch,
166	.restart		= ppc4xx_reset_system,
167	.calibrate_decr		= generic_calibrate_decr,
168};
169