arch/arm/firmware/trusted_foundations.c

   1 /*
   2  * Trusted Foundations support for ARM CPUs
   3  *
   4  * Copyright (c) 2013, NVIDIA Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/init.h>
  19 #include <linux/of.h>
  20 #include <asm/firmware.h>
  21 #include <asm/trusted_foundations.h>
  22
  23 #define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200
  24
  25 static void __naked tf_generic_smc(u32 type, u32 arg1, u32 arg2)
  26 {
  27         asm volatile(
  28                 ".arch_extension        sec\n\t"
  29                 "stmfd  sp!, {r4 - r11, lr}\n\t"
  30                 __asmeq("%0", "r0")
  31                 __asmeq("%1", "r1")
  32                 __asmeq("%2", "r2")
  33                 "mov    r3, #0\n\t"
  34                 "mov    r4, #0\n\t"
  35                 "smc    #0\n\t"
  36                 "ldmfd  sp!, {r4 - r11, pc}"
  37                 :
  38                 : "r" (type), "r" (arg1), "r" (arg2)
  39                 : "memory");
  40 }
  41
  42 static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
  43 {
  44         tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, boot_addr, 0);
  45
  46         return 0;
  47 }
  48
  49 static const struct firmware_ops trusted_foundations_ops = {
  50         .set_cpu_boot_addr = tf_set_cpu_boot_addr,
  51 };
  52
  53 void register_trusted_foundations(struct trusted_foundations_platform_data *pd)
  54 {
  55         /*
  56          * we are not using version information for now since currently
  57          * supported SMCs are compatible with all TF releases
  58          */
  59         register_firmware_ops(&trusted_foundations_ops);
  60 }
  61
  62 void of_register_trusted_foundations(void)
  63 {
  64         struct device_node *node;
  65         struct trusted_foundations_platform_data pdata;
  66         int err;
  67
  68         node = of_find_compatible_node(NULL, NULL, "tlm,trusted-foundations");
  69         if (!node)
  70                 return;
  71
  72         err = of_property_read_u32(node, "tlm,version-major",
  73                                    &pdata.version_major);
  74         if (err != 0)
  75                 panic("Trusted Foundation: missing version-major property\n");
  76         err = of_property_read_u32(node, "tlm,version-minor",
  77                                    &pdata.version_minor);
  78         if (err != 0)
  79                 panic("Trusted Foundation: missing version-minor property\n");
  80         register_trusted_foundations(&pdata);
  81 }