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  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  */
20 #include <linux/kernel.h>
21 #include <linux/init.h>
22 #include <linux/smp.h>
23 #include <linux/spinlock.h>
24 #include <linux/io.h>
25 #include <linux/delay.h>
26 
27 #include <asm/cacheflush.h>
28 #include <asm/smp_plat.h>
29 #include <asm/smp_scu.h>
30 #include <asm/smp_twd.h>
31 
32 #include "common.h"
33 #include "pm-rcar.h"
34 #include "r8a7779.h"
35 
36 #define AVECR IOMEM(0xfe700040)
37 #define R8A7779_SCU_BASE 0xf0000000
38 
39 static struct rcar_sysc_ch r8a7779_ch_cpu1 = {
40 	.chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
41 	.chan_bit = 1, /* ARM1 */
42 	.isr_bit = 1, /* ARM1 */
43 };
44 
45 static struct rcar_sysc_ch r8a7779_ch_cpu2 = {
46 	.chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
47 	.chan_bit = 2, /* ARM2 */
48 	.isr_bit = 2, /* ARM2 */
49 };
50 
51 static struct rcar_sysc_ch r8a7779_ch_cpu3 = {
52 	.chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
53 	.chan_bit = 3, /* ARM3 */
54 	.isr_bit = 3, /* ARM3 */
55 };
56 
57 static struct rcar_sysc_ch *r8a7779_ch_cpu[4] = {
58 	[1] = &r8a7779_ch_cpu1,
59 	[2] = &r8a7779_ch_cpu2,
60 	[3] = &r8a7779_ch_cpu3,
61 };
62 
63 #ifdef CONFIG_HAVE_ARM_TWD
64 static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, R8A7779_SCU_BASE + 0x600, 29);
65 void __init r8a7779_register_twd(void)
66 {
67 	twd_local_timer_register(&twd_local_timer);
68 }
69 #endif
70 
71 static int r8a7779_platform_cpu_kill(unsigned int cpu)
72 {
73 	struct rcar_sysc_ch *ch = NULL;
74 	int ret = -EIO;
75 
76 	cpu = cpu_logical_map(cpu);
77 
78 	if (cpu < ARRAY_SIZE(r8a7779_ch_cpu))
79 		ch = r8a7779_ch_cpu[cpu];
80 
81 	if (ch)
82 		ret = rcar_sysc_power_down(ch);
83 
84 	return ret ? ret : 1;
85 }
86 
87 static int r8a7779_boot_secondary(unsigned int cpu, struct task_struct *idle)
88 {
89 	struct rcar_sysc_ch *ch = NULL;
90 	unsigned int lcpu = cpu_logical_map(cpu);
91 	int ret;
92 
93 	if (lcpu < ARRAY_SIZE(r8a7779_ch_cpu))
94 		ch = r8a7779_ch_cpu[lcpu];
95 
96 	if (ch)
97 		ret = rcar_sysc_power_up(ch);
98 	else
99 		ret = -EIO;
100 
101 	return ret;
102 }
103 
104 static void __init r8a7779_smp_prepare_cpus(unsigned int max_cpus)
105 {
106 	/* Map the reset vector (in headsmp-scu.S, headsmp.S) */
107 	__raw_writel(__pa(shmobile_boot_vector), AVECR);
108 	shmobile_boot_fn = virt_to_phys(shmobile_boot_scu);
109 	shmobile_boot_arg = (unsigned long)shmobile_scu_base;
110 
111 	/* setup r8a7779 specific SCU bits */
112 	shmobile_scu_base = IOMEM(R8A7779_SCU_BASE);
113 	shmobile_smp_scu_prepare_cpus(max_cpus);
114 
115 	r8a7779_pm_init();
116 
117 	/* power off secondary CPUs */
118 	r8a7779_platform_cpu_kill(1);
119 	r8a7779_platform_cpu_kill(2);
120 	r8a7779_platform_cpu_kill(3);
121 }
122 
123 #ifdef CONFIG_HOTPLUG_CPU
124 static int r8a7779_cpu_kill(unsigned int cpu)
125 {
126 	if (shmobile_smp_scu_cpu_kill(cpu))
127 		return r8a7779_platform_cpu_kill(cpu);
128 
129 	return 0;
130 }
131 
132 static int r8a7779_cpu_disable(unsigned int cpu)
133 {
134 	/* only CPU1->3 have power domains, do not allow hotplug of CPU0 */
135 	return cpu == 0 ? -EPERM : 0;
136 }
137 #endif /* CONFIG_HOTPLUG_CPU */
138 
139 struct smp_operations r8a7779_smp_ops  __initdata = {
140 	.smp_prepare_cpus	= r8a7779_smp_prepare_cpus,
141 	.smp_boot_secondary	= r8a7779_boot_secondary,
142 #ifdef CONFIG_HOTPLUG_CPU
143 	.cpu_disable		= r8a7779_cpu_disable,
144 	.cpu_die		= shmobile_smp_scu_cpu_die,
145 	.cpu_kill		= r8a7779_cpu_kill,
146 #endif
147 };
148