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          * On Exynos5 devices the call is ignored by trustzone firmware.
  65          */
  66         if (!soc_is_exynos4210() && !soc_is_exynos4212() &&
  67             !soc_is_exynos4412())
  68                 return 0;
  69
  70         /*
  71          * The second parameter of SMC_CMD_CPU1BOOT command means CPU id.
  72          * But, Exynos4212 has only one secondary CPU so second parameter
  73          * isn't used for informing secure firmware about CPU id.
  74          */
  75         if (soc_is_exynos4212())
  76                 cpu = 0;
  77
  78         exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
  79         return 0;
  80 }
  81
  82 static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
  83 {
  84         void __iomem *boot_reg;
  85
  86         if (!sysram_ns_base_addr)
  87                 return -ENODEV;
  88
  89         boot_reg = sysram_ns_base_addr + 0x1c;
  90
  91         /*
  92          * Almost all Exynos-series of SoCs that run in secure mode don't need
  93          * additional offset for every CPU, with Exynos4412 being the only
  94          * exception.
  95          */
  96         if (soc_is_exynos4412())
  97                 boot_reg += 4 * cpu;
  98
  99         writel_relaxed(boot_addr, boot_reg);
 100         return 0;
 101 }
 102
 103 static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
 104 {
 105         void __iomem *boot_reg;
 106
 107         if (!sysram_ns_base_addr)
 108                 return -ENODEV;
 109
 110         boot_reg = sysram_ns_base_addr + 0x1c;
 111
 112         if (soc_is_exynos4412())
 113                 boot_reg += 4 * cpu;
 114
 115         *boot_addr = readl_relaxed(boot_reg);
 116         return 0;
 117 }
 118
 119 static int exynos_cpu_suspend(unsigned long arg)
 120 {
 121         flush_cache_all();
 122         outer_flush_all();
 123
 124         exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
 125
 126         pr_info("Failed to suspend the system\n");
 127         writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
 128         return 1;
 129 }
 130
 131 static int exynos_suspend(void)
 132 {
 133         if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
 134                 exynos_save_cp15();
 135
 136         writel(EXYNOS_SLEEP_MAGIC, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
 137         writel(__pa_symbol(exynos_cpu_resume_ns),
 138                 sysram_ns_base_addr + EXYNOS_BOOT_ADDR);
 139
 140         return cpu_suspend(0, exynos_cpu_suspend);
 141 }
 142
 143 static int exynos_resume(void)
 144 {
 145         writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
 146
 147         return 0;
 148 }
 149
 150 static const struct firmware_ops exynos_firmware_ops = {
 151         .do_idle                = IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
 152         .set_cpu_boot_addr      = exynos_set_cpu_boot_addr,
 153         .get_cpu_boot_addr      = exynos_get_cpu_boot_addr,
 154         .cpu_boot               = exynos_cpu_boot,
 155         .suspend                = IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
 156         .resume                 = IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,
 157 };
 158
 159 static void exynos_l2_write_sec(unsigned long val, unsigned reg)
 160 {
 161         static int l2cache_enabled;
 162
 163         switch (reg) {
 164         case L2X0_CTRL:
 165                 if (val & L2X0_CTRL_EN) {
 166                         /*
 167                          * Before the cache can be enabled, due to firmware
 168                          * design, SMC_CMD_L2X0INVALL must be called.
 169                          */
 170                         if (!l2cache_enabled) {
 171                                 exynos_smc(SMC_CMD_L2X0INVALL, 0, 0, 0);
 172                                 l2cache_enabled = 1;
 173                         }
 174                 } else {
 175                         l2cache_enabled = 0;
 176                 }
 177                 exynos_smc(SMC_CMD_L2X0CTRL, val, 0, 0);
 178                 break;
 179
 180         case L2X0_DEBUG_CTRL:
 181                 exynos_smc(SMC_CMD_L2X0DEBUG, val, 0, 0);
 182                 break;
 183
 184         default:
 185                 WARN_ONCE(1, "%s: ignoring write to reg 0x%x\n", __func__, reg);
 186         }
 187 }
 188
 189 static void exynos_l2_configure(const struct l2x0_regs *regs)
 190 {
 191         exynos_smc(SMC_CMD_L2X0SETUP1, regs->tag_latency, regs->data_latency,
 192                    regs->prefetch_ctrl);
 193         exynos_smc(SMC_CMD_L2X0SETUP2, regs->pwr_ctrl, regs->aux_ctrl, 0);
 194 }
 195
 196 bool __init exynos_secure_firmware_available(void)
 197 {
 198         struct device_node *nd;
 199         const __be32 *addr;
 200
 201         nd = of_find_compatible_node(NULL, NULL,
 202                                         "samsung,secure-firmware");
 203         if (!nd)
 204                 return false;
 205
 206         addr = of_get_address(nd, 0, NULL, NULL);
 207         of_node_put(nd);
 208         if (!addr) {
 209                 pr_err("%s: No address specified.\n", __func__);
 210                 return false;
 211         }
 212
 213         return true;
 214 }
 215
 216 void __init exynos_firmware_init(void)
 217 {
 218         if (!exynos_secure_firmware_available())
 219                 return;
 220
 221         pr_info("Running under secure firmware.\n");
 222
 223         register_firmware_ops(&exynos_firmware_ops);
 224
 225         /*
 226          * Exynos 4 SoCs (based on Cortex A9 and equipped with L2C-310),
 227          * running under secure firmware, require certain registers of L2
 228          * cache controller to be written in secure mode. Here .write_sec
 229          * callback is provided to perform necessary SMC calls.
 230          */
 231         if (IS_ENABLED(CONFIG_CACHE_L2X0) &&
 232             read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) {
 233                 outer_cache.write_sec = exynos_l2_write_sec;
 234                 outer_cache.configure = exynos_l2_configure;
 235         }
 236 }
 237
 238 #define REG_CPU_STATE_ADDR      (sysram_ns_base_addr + 0x28)
 239 #define BOOT_MODE_MASK          0x1f
 240
 241 void exynos_set_boot_flag(unsigned int cpu, unsigned int mode)
 242 {
 243         unsigned int tmp;
 244
 245         tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
 246
 247         if (mode & BOOT_MODE_MASK)
 248                 tmp &= ~BOOT_MODE_MASK;
 249
 250         tmp |= mode;
 251         writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
 252 }
 253
 254 void exynos_clear_boot_flag(unsigned int cpu, unsigned int mode)
 255 {
 256         unsigned int tmp;
 257
 258         tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
 259         tmp &= ~mode;
 260         writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
 261 }