1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * SMP support for Allwinner SoCs
4 *
5 * Copyright (C) 2013 Maxime Ripard
6 *
7 * Maxime Ripard <maxime.ripard@free-electrons.com>
8 *
9 * Based on code
10 * Copyright (C) 2012-2013 Allwinner Ltd.
11 *
12 */
13
14 #include <linux/delay.h>
15 #include <linux/init.h>
16 #include <linux/io.h>
17 #include <linux/memory.h>
18 #include <linux/of.h>
19 #include <linux/of_address.h>
20 #include <linux/smp.h>
21
22 #define CPUCFG_CPU_PWR_CLAMP_STATUS_REG(cpu) ((cpu) * 0x40 + 0x64)
23 #define CPUCFG_CPU_RST_CTRL_REG(cpu) (((cpu) + 1) * 0x40)
24 #define CPUCFG_CPU_CTRL_REG(cpu) (((cpu) + 1) * 0x40 + 0x04)
25 #define CPUCFG_CPU_STATUS_REG(cpu) (((cpu) + 1) * 0x40 + 0x08)
26 #define CPUCFG_GEN_CTRL_REG 0x184
27 #define CPUCFG_PRIVATE0_REG 0x1a4
28 #define CPUCFG_PRIVATE1_REG 0x1a8
29 #define CPUCFG_DBG_CTL0_REG 0x1e0
30 #define CPUCFG_DBG_CTL1_REG 0x1e4
31
32 #define PRCM_CPU_PWROFF_REG 0x100
33 #define PRCM_CPU_PWR_CLAMP_REG(cpu) (((cpu) * 4) + 0x140)
34
35 static void __iomem *cpucfg_membase;
36 static void __iomem *prcm_membase;
37
38 static DEFINE_SPINLOCK(cpu_lock);
39
40 static void __init sun6i_smp_prepare_cpus(unsigned int max_cpus)
41 {
42 struct device_node *node;
43
44 node = of_find_compatible_node(NULL, NULL, "allwinner,sun6i-a31-prcm");
45 if (!node) {
46 pr_err("Missing A31 PRCM node in the device tree\n");
47 return;
48 }
49
50 prcm_membase = of_iomap(node, 0);
51 of_node_put(node);
52 if (!prcm_membase) {
53 pr_err("Couldn't map A31 PRCM registers\n");
54 return;
55 }
56
57 node = of_find_compatible_node(NULL, NULL,
58 "allwinner,sun6i-a31-cpuconfig");
59 if (!node) {
60 pr_err("Missing A31 CPU config node in the device tree\n");
61 return;
62 }
63
64 cpucfg_membase = of_iomap(node, 0);
65 of_node_put(node);
66 if (!cpucfg_membase)
67 pr_err("Couldn't map A31 CPU config registers\n");
68
69 }
70
71 static int sun6i_smp_boot_secondary(unsigned int cpu,
72 struct task_struct *idle)
73 {
74 u32 reg;
75 int i;
76
77 if (!(prcm_membase && cpucfg_membase))
78 return -EFAULT;
79
80 spin_lock(&cpu_lock);
81
82 /* Set CPU boot address */
83 writel(__pa_symbol(secondary_startup),
84 cpucfg_membase + CPUCFG_PRIVATE0_REG);
85
86 /* Assert the CPU core in reset */
87 writel(0, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
88
89 /* Assert the L1 cache in reset */
90 reg = readl(cpucfg_membase + CPUCFG_GEN_CTRL_REG);
91 writel(reg & ~BIT(cpu), cpucfg_membase + CPUCFG_GEN_CTRL_REG);
92
93 /* Disable external debug access */
94 reg = readl(cpucfg_membase + CPUCFG_DBG_CTL1_REG);
95 writel(reg & ~BIT(cpu), cpucfg_membase + CPUCFG_DBG_CTL1_REG);
96
97 /* Power up the CPU */
98 for (i = 0; i <= 8; i++)
99 writel(0xff >> i, prcm_membase + PRCM_CPU_PWR_CLAMP_REG(cpu));
100 mdelay(10);
101
102 /* Clear CPU power-off gating */
103 reg = readl(prcm_membase + PRCM_CPU_PWROFF_REG);
104 writel(reg & ~BIT(cpu), prcm_membase + PRCM_CPU_PWROFF_REG);
105 mdelay(1);
106
107 /* Deassert the CPU core reset */
108 writel(3, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
109
110 /* Enable back the external debug accesses */
111 reg = readl(cpucfg_membase + CPUCFG_DBG_CTL1_REG);
112 writel(reg | BIT(cpu), cpucfg_membase + CPUCFG_DBG_CTL1_REG);
113
114 spin_unlock(&cpu_lock);
115
116 return 0;
117 }
118
119 static const struct smp_operations sun6i_smp_ops __initconst = {
120 .smp_prepare_cpus = sun6i_smp_prepare_cpus,
121 .smp_boot_secondary = sun6i_smp_boot_secondary,
122 };
123 CPU_METHOD_OF_DECLARE(sun6i_a31_smp, "allwinner,sun6i-a31", &sun6i_smp_ops);
124
125 static void __init sun8i_smp_prepare_cpus(unsigned int max_cpus)
126 {
127 struct device_node *node;
128
129 node = of_find_compatible_node(NULL, NULL, "allwinner,sun8i-a23-prcm");
130 if (!node) {
131 pr_err("Missing A23 PRCM node in the device tree\n");
132 return;
133 }
134
135 prcm_membase = of_iomap(node, 0);
136 of_node_put(node);
137 if (!prcm_membase) {
138 pr_err("Couldn't map A23 PRCM registers\n");
139 return;
140 }
141
142 node = of_find_compatible_node(NULL, NULL,
143 "allwinner,sun8i-a23-cpuconfig");
144 if (!node) {
145 pr_err("Missing A23 CPU config node in the device tree\n");
146 return;
147 }
148
149 cpucfg_membase = of_iomap(node, 0);
150 of_node_put(node);
151 if (!cpucfg_membase)
152 pr_err("Couldn't map A23 CPU config registers\n");
153
154 }
155
156 static int sun8i_smp_boot_secondary(unsigned int cpu,
157 struct task_struct *idle)
158 {
159 u32 reg;
160
161 if (!(prcm_membase && cpucfg_membase))
162 return -EFAULT;
163
164 spin_lock(&cpu_lock);
165
166 /* Set CPU boot address */
167 writel(__pa_symbol(secondary_startup),
168 cpucfg_membase + CPUCFG_PRIVATE0_REG);
169
170 /* Assert the CPU core in reset */
171 writel(0, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
172
173 /* Assert the L1 cache in reset */
174 reg = readl(cpucfg_membase + CPUCFG_GEN_CTRL_REG);
175 writel(reg & ~BIT(cpu), cpucfg_membase + CPUCFG_GEN_CTRL_REG);
176
177 /* Clear CPU power-off gating */
178 reg = readl(prcm_membase + PRCM_CPU_PWROFF_REG);
179 writel(reg & ~BIT(cpu), prcm_membase + PRCM_CPU_PWROFF_REG);
180 mdelay(1);
181
182 /* Deassert the CPU core reset */
183 writel(3, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
184
185 spin_unlock(&cpu_lock);
186
187 return 0;
188 }
189
190 static const struct smp_operations sun8i_smp_ops __initconst = {
191 .smp_prepare_cpus = sun8i_smp_prepare_cpus,
192 .smp_boot_secondary = sun8i_smp_boot_secondary,
193 };
194 CPU_METHOD_OF_DECLARE(sun8i_a23_smp, "allwinner,sun8i-a23", &sun8i_smp_ops);
195
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