xref: /linux/arch/arm/mach-shmobile/smp-r8a7779.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1 /*
2  * SMP support for R-Mobile / SH-Mobile - r8a7779 portion
3  *
4  * Copyright (C) 2011  Renesas Solutions Corp.
5  * Copyright (C) 2011  Magnus Damm
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; version 2 of the License.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/smp.h>
19 #include <linux/spinlock.h>
20 #include <linux/io.h>
21 #include <linux/delay.h>
22 
23 #include <asm/cacheflush.h>
24 #include <asm/smp_plat.h>
25 #include <asm/smp_scu.h>
26 #include <asm/smp_twd.h>
27 
28 #include "common.h"
29 #include "pm-rcar.h"
30 #include "r8a7779.h"
31 
32 #define AVECR IOMEM(0xfe700040)
33 #define R8A7779_SCU_BASE 0xf0000000
34 
35 static struct rcar_sysc_ch r8a7779_ch_cpu1 = {
36 	.chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
37 	.chan_bit = 1, /* ARM1 */
38 	.isr_bit = 1, /* ARM1 */
39 };
40 
41 static struct rcar_sysc_ch r8a7779_ch_cpu2 = {
42 	.chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
43 	.chan_bit = 2, /* ARM2 */
44 	.isr_bit = 2, /* ARM2 */
45 };
46 
47 static struct rcar_sysc_ch r8a7779_ch_cpu3 = {
48 	.chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
49 	.chan_bit = 3, /* ARM3 */
50 	.isr_bit = 3, /* ARM3 */
51 };
52 
53 static struct rcar_sysc_ch *r8a7779_ch_cpu[4] = {
54 	[1] = &r8a7779_ch_cpu1,
55 	[2] = &r8a7779_ch_cpu2,
56 	[3] = &r8a7779_ch_cpu3,
57 };
58 
59 #if defined(CONFIG_HAVE_ARM_TWD) && !defined(CONFIG_ARCH_MULTIPLATFORM)
60 static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, R8A7779_SCU_BASE + 0x600, 29);
61 void __init r8a7779_register_twd(void)
62 {
63 	twd_local_timer_register(&twd_local_timer);
64 }
65 #endif
66 
67 static int r8a7779_platform_cpu_kill(unsigned int cpu)
68 {
69 	struct rcar_sysc_ch *ch = NULL;
70 	int ret = -EIO;
71 
72 	cpu = cpu_logical_map(cpu);
73 
74 	if (cpu < ARRAY_SIZE(r8a7779_ch_cpu))
75 		ch = r8a7779_ch_cpu[cpu];
76 
77 	if (ch)
78 		ret = rcar_sysc_power_down(ch);
79 
80 	return ret ? ret : 1;
81 }
82 
83 static int r8a7779_boot_secondary(unsigned int cpu, struct task_struct *idle)
84 {
85 	struct rcar_sysc_ch *ch = NULL;
86 	unsigned int lcpu = cpu_logical_map(cpu);
87 	int ret;
88 
89 	if (lcpu < ARRAY_SIZE(r8a7779_ch_cpu))
90 		ch = r8a7779_ch_cpu[lcpu];
91 
92 	if (ch)
93 		ret = rcar_sysc_power_up(ch);
94 	else
95 		ret = -EIO;
96 
97 	return ret;
98 }
99 
100 static void __init r8a7779_smp_prepare_cpus(unsigned int max_cpus)
101 {
102 	/* Map the reset vector (in headsmp-scu.S, headsmp.S) */
103 	__raw_writel(__pa(shmobile_boot_vector), AVECR);
104 	shmobile_boot_fn = virt_to_phys(shmobile_boot_scu);
105 	shmobile_boot_arg = (unsigned long)shmobile_scu_base;
106 
107 	/* setup r8a7779 specific SCU bits */
108 	shmobile_scu_base = IOMEM(R8A7779_SCU_BASE);
109 	shmobile_smp_scu_prepare_cpus(max_cpus);
110 
111 	r8a7779_pm_init();
112 
113 	/* power off secondary CPUs */
114 	r8a7779_platform_cpu_kill(1);
115 	r8a7779_platform_cpu_kill(2);
116 	r8a7779_platform_cpu_kill(3);
117 }
118 
119 #ifdef CONFIG_HOTPLUG_CPU
120 static int r8a7779_cpu_kill(unsigned int cpu)
121 {
122 	if (shmobile_smp_scu_cpu_kill(cpu))
123 		return r8a7779_platform_cpu_kill(cpu);
124 
125 	return 0;
126 }
127 
128 static int r8a7779_cpu_disable(unsigned int cpu)
129 {
130 	/* only CPU1->3 have power domains, do not allow hotplug of CPU0 */
131 	return cpu == 0 ? -EPERM : 0;
132 }
133 #endif /* CONFIG_HOTPLUG_CPU */
134 
135 struct smp_operations r8a7779_smp_ops  __initdata = {
136 	.smp_prepare_cpus	= r8a7779_smp_prepare_cpus,
137 	.smp_boot_secondary	= r8a7779_boot_secondary,
138 #ifdef CONFIG_HOTPLUG_CPU
139 	.cpu_disable		= r8a7779_cpu_disable,
140 	.cpu_die		= shmobile_smp_scu_cpu_die,
141 	.cpu_kill		= r8a7779_cpu_kill,
142 #endif
143 };
144