drivers/firmware/trusted_foundations.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Trusted Foundations support for ARM CPUs
   4  *
   5  * Copyright (c) 2013, NVIDIA Corporation.
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10 #include <linux/of.h>
  11
  12 #include <linux/firmware/trusted_foundations.h>
  13
  14 #include <asm/firmware.h>
  15 #include <asm/hardware/cache-l2x0.h>
  16 #include <asm/outercache.h>
  17
  18 #define TF_CACHE_MAINT          0xfffff100
  19
  20 #define TF_CACHE_ENABLE         1
  21 #define TF_CACHE_DISABLE        2
  22 #define TF_CACHE_REENABLE       4
  23
  24 #define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200
  25
  26 #define TF_CPU_PM               0xfffffffc
  27 #define TF_CPU_PM_S3            0xffffffe3
  28 #define TF_CPU_PM_S2            0xffffffe6
  29 #define TF_CPU_PM_S2_NO_MC_CLK  0xffffffe5
  30 #define TF_CPU_PM_S1            0xffffffe4
  31 #define TF_CPU_PM_S1_NOFLUSH_L2 0xffffffe7
  32
  33 static unsigned long tf_idle_mode = TF_PM_MODE_NONE;
  34 static unsigned long cpu_boot_addr;
  35
  36 static void tf_generic_smc(u32 type, u32 arg1, u32 arg2)
  37 {
  38         register u32 r0 asm("r0") = type;
  39         register u32 r1 asm("r1") = arg1;
  40         register u32 r2 asm("r2") = arg2;
  41
  42         asm volatile(
  43                 ".arch_extension        sec\n\t"
  44                 "stmfd  sp!, {r4 - r11}\n\t"
  45                 __asmeq("%0", "r0")
  46                 __asmeq("%1", "r1")
  47                 __asmeq("%2", "r2")
  48                 "mov    r3, #0\n\t"
  49                 "mov    r4, #0\n\t"
  50                 "smc    #0\n\t"
  51                 "ldmfd  sp!, {r4 - r11}\n\t"
  52                 :
  53                 : "r" (r0), "r" (r1), "r" (r2)
  54                 : "memory", "r3", "r12", "lr");
  55 }
  56
  57 static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
  58 {
  59         cpu_boot_addr = boot_addr;
  60         tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, cpu_boot_addr, 0);
  61
  62         return 0;
  63 }
  64
  65 static int tf_prepare_idle(unsigned long mode)
  66 {
  67         switch (mode) {
  68         case TF_PM_MODE_LP0:
  69                 tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S3, cpu_boot_addr);
  70                 break;
  71
  72         case TF_PM_MODE_LP1:
  73                 tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S2, cpu_boot_addr);
  74                 break;
  75
  76         case TF_PM_MODE_LP1_NO_MC_CLK:
  77                 tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S2_NO_MC_CLK,
  78                                cpu_boot_addr);
  79                 break;
  80
  81         case TF_PM_MODE_LP2:
  82                 tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1, cpu_boot_addr);
  83                 break;
  84
  85         case TF_PM_MODE_LP2_NOFLUSH_L2:
  86                 tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1_NOFLUSH_L2,
  87                                cpu_boot_addr);
  88                 break;
  89
  90         case TF_PM_MODE_NONE:
  91                 break;
  92
  93         default:
  94                 return -EINVAL;
  95         }
  96
  97         tf_idle_mode = mode;
  98
  99         return 0;
 100 }
 101
 102 #ifdef CONFIG_CACHE_L2X0
 103 static void tf_cache_write_sec(unsigned long val, unsigned int reg)
 104 {
 105         u32 enable_op, l2x0_way_mask = 0xff;
 106
 107         switch (reg) {
 108         case L2X0_CTRL:
 109                 if (l2x0_saved_regs.aux_ctrl & L310_AUX_CTRL_ASSOCIATIVITY_16)
 110                         l2x0_way_mask = 0xffff;
 111
 112                 switch (tf_idle_mode) {
 113                 case TF_PM_MODE_LP2:
 114                         enable_op = TF_CACHE_REENABLE;
 115                         break;
 116
 117                 default:
 118                         enable_op = TF_CACHE_ENABLE;
 119                         break;
 120                 }
 121
 122                 if (val == L2X0_CTRL_EN)
 123                         tf_generic_smc(TF_CACHE_MAINT, enable_op,
 124                                        l2x0_saved_regs.aux_ctrl);
 125                 else
 126                         tf_generic_smc(TF_CACHE_MAINT, TF_CACHE_DISABLE,
 127                                        l2x0_way_mask);
 128                 break;
 129
 130         default:
 131                 break;
 132         }
 133 }
 134
 135 static int tf_init_cache(void)
 136 {
 137         outer_cache.write_sec = tf_cache_write_sec;
 138
 139         return 0;
 140 }
 141 #endif /* CONFIG_CACHE_L2X0 */
 142
 143 static const struct firmware_ops trusted_foundations_ops = {
 144         .set_cpu_boot_addr = tf_set_cpu_boot_addr,
 145         .prepare_idle = tf_prepare_idle,
 146 #ifdef CONFIG_CACHE_L2X0
 147         .l2x0_init = tf_init_cache,
 148 #endif
 149 };
 150
 151 void register_trusted_foundations(struct trusted_foundations_platform_data *pd)
 152 {
 153         /*
 154          * we are not using version information for now since currently
 155          * supported SMCs are compatible with all TF releases
 156          */
 157         register_firmware_ops(&trusted_foundations_ops);
 158 }
 159
 160 void of_register_trusted_foundations(void)
 161 {
 162         struct device_node *node;
 163         struct trusted_foundations_platform_data pdata;
 164         int err;
 165
 166         node = of_find_compatible_node(NULL, NULL, "tlm,trusted-foundations");
 167         if (!node)
 168                 return;
 169
 170         err = of_property_read_u32(node, "tlm,version-major",
 171                                    &pdata.version_major);
 172         if (err != 0)
 173                 panic("Trusted Foundation: missing version-major property\n");
 174         err = of_property_read_u32(node, "tlm,version-minor",
 175                                    &pdata.version_minor);
 176         if (err != 0)
 177                 panic("Trusted Foundation: missing version-minor property\n");
 178         register_trusted_foundations(&pdata);
 179 }
 180
 181 bool trusted_foundations_registered(void)
 182 {
 183         return firmware_ops == &trusted_foundations_ops;
 184 }