xref: /linux/arch/arm/mach-hisi/hotplug.c (revision f01387d2693813eb5271a3448e6a082322c7d75d)
1 /*
2  * Copyright (c) 2013 Linaro Ltd.
3  * Copyright (c) 2013 Hisilicon Limited.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  */
9 
10 #include <linux/cpu.h>
11 #include <linux/delay.h>
12 #include <linux/io.h>
13 #include <linux/of_address.h>
14 #include <linux/of_platform.h>
15 #include <asm/cacheflush.h>
16 #include <asm/smp_plat.h>
17 #include "core.h"
18 
19 /* Sysctrl registers in Hi3620 SoC */
20 #define SCISOEN				0xc0
21 #define SCISODIS			0xc4
22 #define SCPERPWREN			0xd0
23 #define SCPERPWRDIS			0xd4
24 #define SCCPUCOREEN			0xf4
25 #define SCCPUCOREDIS			0xf8
26 #define SCPERCTRL0			0x200
27 #define SCCPURSTEN			0x410
28 #define SCCPURSTDIS			0x414
29 
30 /*
31  * bit definition in SCISOEN/SCPERPWREN/...
32  *
33  * CPU2_ISO_CTRL	(1 << 5)
34  * CPU3_ISO_CTRL	(1 << 6)
35  * ...
36  */
37 #define CPU2_ISO_CTRL			(1 << 5)
38 
39 /*
40  * bit definition in SCPERCTRL0
41  *
42  * CPU0_WFI_MASK_CFG	(1 << 28)
43  * CPU1_WFI_MASK_CFG	(1 << 29)
44  * ...
45  */
46 #define CPU0_WFI_MASK_CFG		(1 << 28)
47 
48 /*
49  * bit definition in SCCPURSTEN/...
50  *
51  * CPU0_SRST_REQ_EN	(1 << 0)
52  * CPU1_SRST_REQ_EN	(1 << 1)
53  * ...
54  */
55 #define CPU0_HPM_SRST_REQ_EN		(1 << 22)
56 #define CPU0_DBG_SRST_REQ_EN		(1 << 12)
57 #define CPU0_NEON_SRST_REQ_EN		(1 << 4)
58 #define CPU0_SRST_REQ_EN		(1 << 0)
59 
60 enum {
61 	HI3620_CTRL,
62 	ERROR_CTRL,
63 };
64 
65 static void __iomem *ctrl_base;
66 static int id;
67 
68 static void set_cpu_hi3620(int cpu, bool enable)
69 {
70 	u32 val = 0;
71 
72 	if (enable) {
73 		/* MTCMOS set */
74 		if ((cpu == 2) || (cpu == 3))
75 			writel_relaxed(CPU2_ISO_CTRL << (cpu - 2),
76 				       ctrl_base + SCPERPWREN);
77 		udelay(100);
78 
79 		/* Enable core */
80 		writel_relaxed(0x01 << cpu, ctrl_base + SCCPUCOREEN);
81 
82 		/* unreset */
83 		val = CPU0_DBG_SRST_REQ_EN | CPU0_NEON_SRST_REQ_EN
84 			| CPU0_SRST_REQ_EN;
85 		writel_relaxed(val << cpu, ctrl_base + SCCPURSTDIS);
86 		/* reset */
87 		val |= CPU0_HPM_SRST_REQ_EN;
88 		writel_relaxed(val << cpu, ctrl_base + SCCPURSTEN);
89 
90 		/* ISO disable */
91 		if ((cpu == 2) || (cpu == 3))
92 			writel_relaxed(CPU2_ISO_CTRL << (cpu - 2),
93 				       ctrl_base + SCISODIS);
94 		udelay(1);
95 
96 		/* WFI Mask */
97 		val = readl_relaxed(ctrl_base + SCPERCTRL0);
98 		val &= ~(CPU0_WFI_MASK_CFG << cpu);
99 		writel_relaxed(val, ctrl_base + SCPERCTRL0);
100 
101 		/* Unreset */
102 		val = CPU0_DBG_SRST_REQ_EN | CPU0_NEON_SRST_REQ_EN
103 			| CPU0_SRST_REQ_EN | CPU0_HPM_SRST_REQ_EN;
104 		writel_relaxed(val << cpu, ctrl_base + SCCPURSTDIS);
105 	} else {
106 		/* wfi mask */
107 		val = readl_relaxed(ctrl_base + SCPERCTRL0);
108 		val |= (CPU0_WFI_MASK_CFG << cpu);
109 		writel_relaxed(val, ctrl_base + SCPERCTRL0);
110 
111 		/* disable core*/
112 		writel_relaxed(0x01 << cpu, ctrl_base + SCCPUCOREDIS);
113 
114 		if ((cpu == 2) || (cpu == 3)) {
115 			/* iso enable */
116 			writel_relaxed(CPU2_ISO_CTRL << (cpu - 2),
117 				       ctrl_base + SCISOEN);
118 			udelay(1);
119 		}
120 
121 		/* reset */
122 		val = CPU0_DBG_SRST_REQ_EN | CPU0_NEON_SRST_REQ_EN
123 			| CPU0_SRST_REQ_EN | CPU0_HPM_SRST_REQ_EN;
124 		writel_relaxed(val << cpu, ctrl_base + SCCPURSTEN);
125 
126 		if ((cpu == 2) || (cpu == 3)) {
127 			/* MTCMOS unset */
128 			writel_relaxed(CPU2_ISO_CTRL << (cpu - 2),
129 				       ctrl_base + SCPERPWRDIS);
130 			udelay(100);
131 		}
132 	}
133 }
134 
135 static int hi3xxx_hotplug_init(void)
136 {
137 	struct device_node *node;
138 
139 	node = of_find_compatible_node(NULL, NULL, "hisilicon,sysctrl");
140 	if (node) {
141 		ctrl_base = of_iomap(node, 0);
142 		id = HI3620_CTRL;
143 		return 0;
144 	}
145 	id = ERROR_CTRL;
146 	return -ENOENT;
147 }
148 
149 void hi3xxx_set_cpu(int cpu, bool enable)
150 {
151 	if (!ctrl_base) {
152 		if (hi3xxx_hotplug_init() < 0)
153 			return;
154 	}
155 
156 	if (id == HI3620_CTRL)
157 		set_cpu_hi3620(cpu, enable);
158 }
159 
160 static inline void cpu_enter_lowpower(void)
161 {
162 	unsigned int v;
163 
164 	flush_cache_all();
165 
166 	/*
167 	 * Turn off coherency and L1 D-cache
168 	 */
169 	asm volatile(
170 	"	mrc	p15, 0, %0, c1, c0, 1\n"
171 	"	bic	%0, %0, #0x40\n"
172 	"	mcr	p15, 0, %0, c1, c0, 1\n"
173 	"	mrc	p15, 0, %0, c1, c0, 0\n"
174 	"	bic	%0, %0, #0x04\n"
175 	"	mcr	p15, 0, %0, c1, c0, 0\n"
176 	  : "=&r" (v)
177 	  : "r" (0)
178 	  : "cc");
179 }
180 
181 #ifdef CONFIG_HOTPLUG_CPU
182 void hi3xxx_cpu_die(unsigned int cpu)
183 {
184 	cpu_enter_lowpower();
185 	hi3xxx_set_cpu_jump(cpu, phys_to_virt(0));
186 	cpu_do_idle();
187 
188 	/* We should have never returned from idle */
189 	panic("cpu %d unexpectedly exit from shutdown\n", cpu);
190 }
191 
192 int hi3xxx_cpu_kill(unsigned int cpu)
193 {
194 	unsigned long timeout = jiffies + msecs_to_jiffies(50);
195 
196 	while (hi3xxx_get_cpu_jump(cpu))
197 		if (time_after(jiffies, timeout))
198 			return 0;
199 	hi3xxx_set_cpu(cpu, false);
200 	return 1;
201 }
202 #endif
203