arch/arm/mach-exynos/firmware.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 //
   3 // Copyright (C) 2012 Samsung Electronics.
   4 // Kyungmin Park <kyungmin.park@samsung.com>
   5 // Tomasz Figa <t.figa@samsung.com>
   6
   7 #include <linux/kernel.h>
   8 #include <linux/io.h>
   9 #include <linux/init.h>
  10 #include <linux/of.h>
  11 #include <linux/of_address.h>
  12
  13 #include <asm/cacheflush.h>
  14 #include <asm/cputype.h>
  15 #include <asm/firmware.h>
  16 #include <asm/hardware/cache-l2x0.h>
  17 #include <asm/suspend.h>
  18
  19 #include "common.h"
  20 #include "smc.h"
  21
  22 #define EXYNOS_BOOT_ADDR        0x8
  23 #define EXYNOS_BOOT_FLAG        0xc
  24
  25 static void exynos_save_cp15(void)
  26 {
  27         /* Save Power control and Diagnostic registers */
  28         asm ("mrc p15, 0, %0, c15, c0, 0\n"
  29              "mrc p15, 0, %1, c15, c0, 1\n"
  30              : "=r" (cp15_save_power), "=r" (cp15_save_diag)
  31              : : "cc");
  32 }
  33
  34 static int exynos_do_idle(unsigned long mode)
  35 {
  36         switch (mode) {
  37         case FW_DO_IDLE_AFTR:
  38                 if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
  39                         exynos_save_cp15();
  40                 writel_relaxed(__pa_symbol(exynos_cpu_resume_ns),
  41                                sysram_ns_base_addr + 0x24);
  42                 writel_relaxed(EXYNOS_AFTR_MAGIC, sysram_ns_base_addr + 0x20);
  43                 if (soc_is_exynos3250()) {
  44                         flush_cache_all();
  45                         exynos_smc(SMC_CMD_SAVE, OP_TYPE_CORE,
  46                                    SMC_POWERSTATE_IDLE, 0);
  47                         exynos_smc(SMC_CMD_SHUTDOWN, OP_TYPE_CLUSTER,
  48                                    SMC_POWERSTATE_IDLE, 0);
  49                 } else
  50                         exynos_smc(SMC_CMD_CPU0AFTR, 0, 0, 0);
  51                 break;
  52         case FW_DO_IDLE_SLEEP:
  53                 exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
  54         }
  55         return 0;
  56 }
  57
  58 static int exynos_cpu_boot(int cpu)
  59 {
  60         /*
  61          * Exynos3250 doesn't need to send smc command for secondary CPU boot
  62          * because Exynos3250 removes WFE in secure mode.
  63          */
  64         if (soc_is_exynos3250())
  65                 return 0;
  66
  67         /*
  68          * The second parameter of SMC_CMD_CPU1BOOT command means CPU id.
  69          */
  70         exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
  71         return 0;
  72 }
  73
  74 static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
  75 {
  76         void __iomem *boot_reg;
  77
  78         if (!sysram_ns_base_addr)
  79                 return -ENODEV;
  80
  81         boot_reg = sysram_ns_base_addr + 0x1c;
  82
  83         /*
  84          * Almost all Exynos-series of SoCs that run in secure mode don't need
  85          * additional offset for every CPU, with Exynos4412 being the only
  86          * exception.
  87          */
  88         if (soc_is_exynos4412())
  89                 boot_reg += 4 * cpu;
  90
  91         writel_relaxed(boot_addr, boot_reg);
  92         return 0;
  93 }
  94
  95 static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
  96 {
  97         void __iomem *boot_reg;
  98
  99         if (!sysram_ns_base_addr)
 100                 return -ENODEV;
 101
 102         boot_reg = sysram_ns_base_addr + 0x1c;
 103
 104         if (soc_is_exynos4412())
 105                 boot_reg += 4 * cpu;
 106
 107         *boot_addr = readl_relaxed(boot_reg);
 108         return 0;
 109 }
 110
 111 static int exynos_cpu_suspend(unsigned long arg)
 112 {
 113         flush_cache_all();
 114         outer_flush_all();
 115
 116         exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
 117
 118         pr_info("Failed to suspend the system\n");
 119         writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
 120         return 1;
 121 }
 122
 123 static int exynos_suspend(void)
 124 {
 125         if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
 126                 exynos_save_cp15();
 127
 128         writel(EXYNOS_SLEEP_MAGIC, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
 129         writel(__pa_symbol(exynos_cpu_resume_ns),
 130                 sysram_ns_base_addr + EXYNOS_BOOT_ADDR);
 131
 132         return cpu_suspend(0, exynos_cpu_suspend);
 133 }
 134
 135 static int exynos_resume(void)
 136 {
 137         writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
 138
 139         return 0;
 140 }
 141
 142 static const struct firmware_ops exynos_firmware_ops = {
 143         .do_idle                = IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
 144         .set_cpu_boot_addr      = exynos_set_cpu_boot_addr,
 145         .get_cpu_boot_addr      = exynos_get_cpu_boot_addr,
 146         .cpu_boot               = exynos_cpu_boot,
 147         .suspend                = IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
 148         .resume                 = IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,
 149 };
 150
 151 static void exynos_l2_write_sec(unsigned long val, unsigned reg)
 152 {
 153         static int l2cache_enabled;
 154
 155         switch (reg) {
 156         case L2X0_CTRL:
 157                 if (val & L2X0_CTRL_EN) {
 158                         /*
 159                          * Before the cache can be enabled, due to firmware
 160                          * design, SMC_CMD_L2X0INVALL must be called.
 161                          */
 162                         if (!l2cache_enabled) {
 163                                 exynos_smc(SMC_CMD_L2X0INVALL, 0, 0, 0);
 164                                 l2cache_enabled = 1;
 165                         }
 166                 } else {
 167                         l2cache_enabled = 0;
 168                 }
 169                 exynos_smc(SMC_CMD_L2X0CTRL, val, 0, 0);
 170                 break;
 171
 172         case L2X0_DEBUG_CTRL:
 173                 exynos_smc(SMC_CMD_L2X0DEBUG, val, 0, 0);
 174                 break;
 175
 176         default:
 177                 WARN_ONCE(1, "%s: ignoring write to reg 0x%x\n", __func__, reg);
 178         }
 179 }
 180
 181 static void exynos_l2_configure(const struct l2x0_regs *regs)
 182 {
 183         exynos_smc(SMC_CMD_L2X0SETUP1, regs->tag_latency, regs->data_latency,
 184                    regs->prefetch_ctrl);
 185         exynos_smc(SMC_CMD_L2X0SETUP2, regs->pwr_ctrl, regs->aux_ctrl, 0);
 186 }
 187
 188 bool __init exynos_secure_firmware_available(void)
 189 {
 190         struct device_node *nd;
 191         const __be32 *addr;
 192
 193         nd = of_find_compatible_node(NULL, NULL,
 194                                         "samsung,secure-firmware");
 195         if (!nd)
 196                 return false;
 197
 198         addr = of_get_address(nd, 0, NULL, NULL);
 199         of_node_put(nd);
 200         if (!addr) {
 201                 pr_err("%s: No address specified.\n", __func__);
 202                 return false;
 203         }
 204
 205         return true;
 206 }
 207
 208 void __init exynos_firmware_init(void)
 209 {
 210         if (!exynos_secure_firmware_available())
 211                 return;
 212
 213         pr_info("Running under secure firmware.\n");
 214
 215         register_firmware_ops(&exynos_firmware_ops);
 216
 217         /*
 218          * Exynos 4 SoCs (based on Cortex A9 and equipped with L2C-310),
 219          * running under secure firmware, require certain registers of L2
 220          * cache controller to be written in secure mode. Here .write_sec
 221          * callback is provided to perform necessary SMC calls.
 222          */
 223         if (IS_ENABLED(CONFIG_CACHE_L2X0) &&
 224             read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) {
 225                 outer_cache.write_sec = exynos_l2_write_sec;
 226                 outer_cache.configure = exynos_l2_configure;
 227         }
 228 }
 229
 230 #define REG_CPU_STATE_ADDR      (sysram_ns_base_addr + 0x28)
 231 #define BOOT_MODE_MASK          0x1f
 232
 233 void exynos_set_boot_flag(unsigned int cpu, unsigned int mode)
 234 {
 235         unsigned int tmp;
 236
 237         tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
 238
 239         if (mode & BOOT_MODE_MASK)
 240                 tmp &= ~BOOT_MODE_MASK;
 241
 242         tmp |= mode;
 243         writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
 244 }
 245
 246 void exynos_clear_boot_flag(unsigned int cpu, unsigned int mode)
 247 {
 248         unsigned int tmp;
 249
 250         tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
 251         tmp &= ~mode;
 252         writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
 253 }