summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-vexpress/platsmp.c
blob: 3bc0e38d70f75d197e8bd55ee0c1437c5fbb14d6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
/*
 *  linux/arch/arm/mach-vexpress/platsmp.c
 *
 *  Copyright (C) 2002 ARM Ltd.
 *  All Rights Reserved
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <linux/of_fdt.h>
#include <linux/vexpress.h>

#include <asm/smp_scu.h>
#include <asm/hardware/gic.h>
#include <asm/mach/map.h>

#include <mach/motherboard.h>

#include <plat/platsmp.h>

#include "core.h"

#if defined(CONFIG_OF)

static enum {
	GENERIC_SCU,
	CORTEX_A9_SCU,
} vexpress_dt_scu __initdata = GENERIC_SCU;

static struct map_desc vexpress_dt_cortex_a9_scu_map __initdata = {
	.virtual	= V2T_PERIPH,
	/* .pfn	set in vexpress_dt_init_cortex_a9_scu() */
	.length		= SZ_128,
	.type		= MT_DEVICE,
};

static void *vexpress_dt_cortex_a9_scu_base __initdata;

const static char *vexpress_dt_cortex_a9_match[] __initconst = {
	"arm,cortex-a5-scu",
	"arm,cortex-a9-scu",
	NULL
};

static int __init vexpress_dt_find_scu(unsigned long node,
		const char *uname, int depth, void *data)
{
	if (of_flat_dt_match(node, vexpress_dt_cortex_a9_match)) {
		phys_addr_t phys_addr;
		__be32 *reg = of_get_flat_dt_prop(node, "reg", NULL);

		if (WARN_ON(!reg))
			return -EINVAL;

		phys_addr = be32_to_cpup(reg);
		vexpress_dt_scu = CORTEX_A9_SCU;

		vexpress_dt_cortex_a9_scu_map.pfn = __phys_to_pfn(phys_addr);
		iotable_init(&vexpress_dt_cortex_a9_scu_map, 1);
		vexpress_dt_cortex_a9_scu_base = ioremap(phys_addr, SZ_256);
		if (WARN_ON(!vexpress_dt_cortex_a9_scu_base))
			return -EFAULT;
	}

	return 0;
}

void __init vexpress_dt_smp_map_io(void)
{
	if (initial_boot_params)
		WARN_ON(of_scan_flat_dt(vexpress_dt_find_scu, NULL));
}

static int __init vexpress_dt_cpus_num(unsigned long node, const char *uname,
		int depth, void *data)
{
	static int prev_depth = -1;
	static int nr_cpus = -1;

	if (prev_depth > depth && nr_cpus > 0)
		return nr_cpus;

	if (nr_cpus < 0 && strcmp(uname, "cpus") == 0)
		nr_cpus = 0;

	if (nr_cpus >= 0) {
		const char *device_type = of_get_flat_dt_prop(node,
				"device_type", NULL);

		if (device_type && strcmp(device_type, "cpu") == 0)
			nr_cpus++;
	}

	prev_depth = depth;

	return 0;
}

static void __init vexpress_dt_smp_init_cpus(void)
{
	int ncores = 0, i;

	switch (vexpress_dt_scu) {
	case GENERIC_SCU:
		ncores = of_scan_flat_dt(vexpress_dt_cpus_num, NULL);
		break;
	case CORTEX_A9_SCU:
		ncores = scu_get_core_count(vexpress_dt_cortex_a9_scu_base);
		break;
	default:
		WARN_ON(1);
		break;
	}

	if (ncores < 2)
		return;

	if (ncores > nr_cpu_ids) {
		pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
				ncores, nr_cpu_ids);
		ncores = nr_cpu_ids;
	}

	for (i = 0; i < ncores; ++i)
		set_cpu_possible(i, true);
}

static void __init vexpress_dt_smp_prepare_cpus(unsigned int max_cpus)
{
	int i;

	switch (vexpress_dt_scu) {
	case GENERIC_SCU:
		for (i = 0; i < max_cpus; i++)
			set_cpu_present(i, true);
		break;
	case CORTEX_A9_SCU:
		scu_enable(vexpress_dt_cortex_a9_scu_base);
		break;
	default:
		WARN_ON(1);
		break;
	}
}

#else

static void __init vexpress_dt_smp_init_cpus(void)
{
	WARN_ON(1);
}

void __init vexpress_dt_smp_prepare_cpus(unsigned int max_cpus)
{
	WARN_ON(1);
}

#endif

/*
 * Initialise the CPU possible map early - this describes the CPUs
 * which may be present or become present in the system.
 */
static void __init vexpress_smp_init_cpus(void)
{
	if (ct_desc)
		ct_desc->init_cpu_map();
	else
		vexpress_dt_smp_init_cpus();

}

static void __init vexpress_smp_prepare_cpus(unsigned int max_cpus)
{
	/*
	 * Initialise the present map, which describes the set of CPUs
	 * actually populated at the present time.
	 */
	if (ct_desc)
		ct_desc->smp_enable(max_cpus);
	else
		vexpress_dt_smp_prepare_cpus(max_cpus);

	/*
	 * Write the address of secondary startup into the
	 * system-wide flags register. The boot monitor waits
	 * until it receives a soft interrupt, and then the
	 * secondary CPU branches to this address.
	 */
	vexpress_flags_set(virt_to_phys(versatile_secondary_startup));
}

struct smp_operations __initdata vexpress_smp_ops = {
	.smp_init_cpus		= vexpress_smp_init_cpus,
	.smp_prepare_cpus	= vexpress_smp_prepare_cpus,
	.smp_secondary_init	= versatile_secondary_init,
	.smp_boot_secondary	= versatile_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
	.cpu_die		= vexpress_cpu_die,
#endif
};