summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-socfpga/platsmp.c
blob: 0ee76772b50743f099637e18b4859d5736644b23 (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
/*
 * Copyright 2010-2011 Calxeda, Inc.
 * Copyright 2012 Pavel Machek <pavel@denx.de>
 * Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
 * Copyright (C) 2012 Altera Corporation
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
 */
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>

#include <asm/cacheflush.h>
#include <asm/smp_scu.h>
#include <asm/smp_plat.h>

#include "core.h"

static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
	int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;

	if (socfpga_cpu1start_addr) {
		/* This will put CPU #1 into reset. */
		writel(RSTMGR_MPUMODRST_CPU1,
		       rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);

		memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);

		writel(__pa_symbol(secondary_startup),
		       sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff));

		flush_cache_all();
		smp_wmb();
		outer_clean_range(0, trampoline_size);

		/* This will release CPU #1 out of reset. */
		writel(0, rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
	}

	return 0;
}

static int socfpga_a10_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
	int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;

	if (socfpga_cpu1start_addr) {
		writel(RSTMGR_MPUMODRST_CPU1, rst_manager_base_addr +
		       SOCFPGA_A10_RSTMGR_MODMPURST);
		memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);

		writel(__pa_symbol(secondary_startup),
		       sys_manager_base_addr + (socfpga_cpu1start_addr & 0x00000fff));

		flush_cache_all();
		smp_wmb();
		outer_clean_range(0, trampoline_size);

		/* This will release CPU #1 out of reset. */
		writel(0, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_MODMPURST);
	}

	return 0;
}

static void __init socfpga_smp_prepare_cpus(unsigned int max_cpus)
{
	struct device_node *np;
	void __iomem *socfpga_scu_base_addr;

	np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
	if (!np) {
		pr_err("%s: missing scu\n", __func__);
		return;
	}

	socfpga_scu_base_addr = of_iomap(np, 0);
	if (!socfpga_scu_base_addr)
		return;
	scu_enable(socfpga_scu_base_addr);
}

#ifdef CONFIG_HOTPLUG_CPU
/*
 * platform-specific code to shutdown a CPU
 *
 * Called with IRQs disabled
 */
static void socfpga_cpu_die(unsigned int cpu)
{
	/* Do WFI. If we wake up early, go back into WFI */
	while (1)
		cpu_do_idle();
}

/*
 * We need a dummy function so that platform_can_cpu_hotplug() knows
 * we support CPU hotplug. However, the function does not need to do
 * anything, because CPUs going offline just do WFI. We could reset
 * the CPUs but it would increase power consumption.
 */
static int socfpga_cpu_kill(unsigned int cpu)
{
	return 1;
}
#endif

static const struct smp_operations socfpga_smp_ops __initconst = {
	.smp_prepare_cpus	= socfpga_smp_prepare_cpus,
	.smp_boot_secondary	= socfpga_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
	.cpu_die		= socfpga_cpu_die,
	.cpu_kill		= socfpga_cpu_kill,
#endif
};

static const struct smp_operations socfpga_a10_smp_ops __initconst = {
	.smp_prepare_cpus	= socfpga_smp_prepare_cpus,
	.smp_boot_secondary	= socfpga_a10_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
	.cpu_die		= socfpga_cpu_die,
	.cpu_kill		= socfpga_cpu_kill,
#endif
};

CPU_METHOD_OF_DECLARE(socfpga_smp, "altr,socfpga-smp", &socfpga_smp_ops);
CPU_METHOD_OF_DECLARE(socfpga_a10_smp, "altr,socfpga-a10-smp", &socfpga_a10_smp_ops);