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
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
|
// SPDX-License-Identifier: GPL-2.0
/*
* SMP support for SoCs with APMU
*
* Copyright (C) 2014 Renesas Electronics Corporation
* Copyright (C) 2013 Magnus Damm
*/
#include <linux/cpu_pm.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/of_address.h>
#include <linux/smp.h>
#include <linux/suspend.h>
#include <linux/threads.h>
#include <asm/cacheflush.h>
#include <asm/cp15.h>
#include <asm/proc-fns.h>
#include <asm/smp_plat.h>
#include <asm/suspend.h>
#include "common.h"
#include "rcar-gen2.h"
static struct {
void __iomem *iomem;
int bit;
} apmu_cpus[NR_CPUS];
#define WUPCR_OFFS 0x10 /* Wake Up Control Register */
#define PSTR_OFFS 0x40 /* Power Status Register */
#define CPUNCR_OFFS(n) (0x100 + (0x10 * (n)))
/* CPUn Power Status Control Register */
#define DBGRCR_OFFS 0x180 /* Debug Resource Reset Control Reg. */
/* Power Status Register */
#define CPUNST(r, n) (((r) >> (n * 4)) & 3) /* CPUn Status Bit */
#define CPUST_RUN 0 /* Run Mode */
#define CPUST_STANDBY 3 /* CoreStandby Mode */
/* Debug Resource Reset Control Register */
#define DBGCPUREN BIT(24) /* CPU Other Reset Request Enable */
#define DBGCPUNREN(n) BIT((n) + 20) /* CPUn Reset Request Enable */
#define DBGCPUPREN BIT(19) /* CPU Peripheral Reset Req. Enable */
static int __maybe_unused apmu_power_on(void __iomem *p, int bit)
{
/* request power on */
writel_relaxed(BIT(bit), p + WUPCR_OFFS);
/* wait for APMU to finish */
while (readl_relaxed(p + WUPCR_OFFS) != 0)
;
return 0;
}
static int __maybe_unused apmu_power_off(void __iomem *p, int bit)
{
/* request Core Standby for next WFI */
writel_relaxed(3, p + CPUNCR_OFFS(bit));
return 0;
}
static int __maybe_unused apmu_power_off_poll(void __iomem *p, int bit)
{
int k;
for (k = 0; k < 1000; k++) {
if (CPUNST(readl_relaxed(p + PSTR_OFFS), bit) == CPUST_STANDBY)
return 1;
mdelay(1);
}
return 0;
}
static int __maybe_unused apmu_wrap(int cpu, int (*fn)(void __iomem *p, int cpu))
{
void __iomem *p = apmu_cpus[cpu].iomem;
return p ? fn(p, apmu_cpus[cpu].bit) : -EINVAL;
}
#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_SUSPEND)
/* nicked from arch/arm/mach-exynos/hotplug.c */
static inline void cpu_enter_lowpower_a15(void)
{
unsigned int v;
asm volatile(
" mrc p15, 0, %0, c1, c0, 0\n"
" bic %0, %0, %1\n"
" mcr p15, 0, %0, c1, c0, 0\n"
: "=&r" (v)
: "Ir" (CR_C)
: "cc");
flush_cache_louis();
asm volatile(
/*
* Turn off coherency
*/
" mrc p15, 0, %0, c1, c0, 1\n"
" bic %0, %0, %1\n"
" mcr p15, 0, %0, c1, c0, 1\n"
: "=&r" (v)
: "Ir" (0x40)
: "cc");
isb();
dsb();
}
static void shmobile_smp_apmu_cpu_shutdown(unsigned int cpu)
{
/* Select next sleep mode using the APMU */
apmu_wrap(cpu, apmu_power_off);
/* Do ARM specific CPU shutdown */
cpu_enter_lowpower_a15();
}
#endif
#if defined(CONFIG_HOTPLUG_CPU)
static void shmobile_smp_apmu_cpu_die(unsigned int cpu)
{
/* For this particular CPU deregister boot vector */
shmobile_smp_hook(cpu, 0, 0);
/* Shutdown CPU core */
shmobile_smp_apmu_cpu_shutdown(cpu);
/* jump to shared mach-shmobile sleep / reset code */
shmobile_smp_sleep();
}
static int shmobile_smp_apmu_cpu_kill(unsigned int cpu)
{
return apmu_wrap(cpu, apmu_power_off_poll);
}
#endif
#if defined(CONFIG_SUSPEND)
static int shmobile_smp_apmu_do_suspend(unsigned long cpu)
{
shmobile_smp_hook(cpu, __pa_symbol(cpu_resume), 0);
shmobile_smp_apmu_cpu_shutdown(cpu);
cpu_do_idle(); /* WFI selects Core Standby */
return 1;
}
static inline void cpu_leave_lowpower(void)
{
unsigned int v;
asm volatile("mrc p15, 0, %0, c1, c0, 0\n"
" orr %0, %0, %1\n"
" mcr p15, 0, %0, c1, c0, 0\n"
" mrc p15, 0, %0, c1, c0, 1\n"
" orr %0, %0, %2\n"
" mcr p15, 0, %0, c1, c0, 1\n"
: "=&r" (v)
: "Ir" (CR_C), "Ir" (0x40)
: "cc");
}
static int shmobile_smp_apmu_enter_suspend(suspend_state_t state)
{
cpu_suspend(smp_processor_id(), shmobile_smp_apmu_do_suspend);
cpu_leave_lowpower();
return 0;
}
void __init shmobile_smp_apmu_suspend_init(void)
{
shmobile_suspend_ops.enter = shmobile_smp_apmu_enter_suspend;
}
#endif
#ifdef CONFIG_SMP
static void apmu_init_cpu(struct resource *res, int cpu, int bit)
{
u32 x;
if ((cpu >= ARRAY_SIZE(apmu_cpus)) || apmu_cpus[cpu].iomem)
return;
apmu_cpus[cpu].iomem = ioremap_nocache(res->start, resource_size(res));
apmu_cpus[cpu].bit = bit;
pr_debug("apmu ioremap %d %d %pr\n", cpu, bit, res);
/* Setup for debug mode */
x = readl(apmu_cpus[cpu].iomem + DBGRCR_OFFS);
x |= DBGCPUREN | DBGCPUNREN(bit) | DBGCPUPREN;
writel(x, apmu_cpus[cpu].iomem + DBGRCR_OFFS);
}
static const struct of_device_id apmu_ids[] = {
{ .compatible = "renesas,apmu" },
{ /*sentinel*/ }
};
static void apmu_parse_dt(void (*fn)(struct resource *res, int cpu, int bit))
{
struct device_node *np_apmu, *np_cpu;
struct resource res;
int bit, index;
u32 id;
for_each_matching_node(np_apmu, apmu_ids) {
/* only enable the cluster that includes the boot CPU */
bool is_allowed = false;
for (bit = 0; bit < CONFIG_NR_CPUS; bit++) {
np_cpu = of_parse_phandle(np_apmu, "cpus", bit);
if (np_cpu) {
if (!of_property_read_u32(np_cpu, "reg", &id)) {
if (id == cpu_logical_map(0)) {
is_allowed = true;
of_node_put(np_cpu);
break;
}
}
of_node_put(np_cpu);
}
}
if (!is_allowed)
continue;
for (bit = 0; bit < CONFIG_NR_CPUS; bit++) {
np_cpu = of_parse_phandle(np_apmu, "cpus", bit);
if (np_cpu) {
if (!of_property_read_u32(np_cpu, "reg", &id)) {
index = get_logical_index(id);
if ((index >= 0) &&
!of_address_to_resource(np_apmu,
0, &res))
fn(&res, index, bit);
}
of_node_put(np_cpu);
}
}
}
}
static void __init shmobile_smp_apmu_setup_boot(void)
{
/* install boot code shared by all CPUs */
shmobile_boot_fn = __pa_symbol(shmobile_smp_boot);
shmobile_boot_fn_gen2 = shmobile_boot_fn;
}
static int shmobile_smp_apmu_boot_secondary(unsigned int cpu,
struct task_struct *idle)
{
/* For this particular CPU register boot vector */
shmobile_smp_hook(cpu, __pa_symbol(shmobile_boot_apmu), 0);
return apmu_wrap(cpu, apmu_power_on);
}
static void __init shmobile_smp_apmu_prepare_cpus_dt(unsigned int max_cpus)
{
shmobile_smp_apmu_setup_boot();
apmu_parse_dt(apmu_init_cpu);
rcar_gen2_pm_init();
}
static struct smp_operations apmu_smp_ops __initdata = {
.smp_prepare_cpus = shmobile_smp_apmu_prepare_cpus_dt,
.smp_boot_secondary = shmobile_smp_apmu_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_can_disable = shmobile_smp_cpu_can_disable,
.cpu_die = shmobile_smp_apmu_cpu_die,
.cpu_kill = shmobile_smp_apmu_cpu_kill,
#endif
};
CPU_METHOD_OF_DECLARE(shmobile_smp_apmu, "renesas,apmu", &apmu_smp_ops);
#endif /* CONFIG_SMP */
|
