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