platsmp.c (5077B)
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 35static void __iomem *cpucfg_membase; 36static void __iomem *prcm_membase; 37 38static DEFINE_SPINLOCK(cpu_lock); 39 40static 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 71static 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 119static 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}; 123CPU_METHOD_OF_DECLARE(sun6i_a31_smp, "allwinner,sun6i-a31", &sun6i_smp_ops); 124 125static 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 156static 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 190static 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}; 194CPU_METHOD_OF_DECLARE(sun8i_a23_smp, "allwinner,sun8i-a23", &sun8i_smp_ops);