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