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 #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 __naked tf_generic_smc(u32 type, u32 arg1, u32 arg2)
  35 {
  36         asm volatile(
  37                 ".arch_extension        sec\n\t"
  38                 "stmfd  sp!, {r4 - r11, lr}\n\t"
  39                 __asmeq("%0", "r0")
  40                 __asmeq("%1", "r1")
  41                 __asmeq("%2", "r2")
  42                 "mov    r3, #0\n\t"
  43                 "mov    r4, #0\n\t"
  44                 "smc    #0\n\t"
  45                 "ldmfd  sp!, {r4 - r11, pc}"
  46                 :
  47                 : "r" (type), "r" (arg1), "r" (arg2)
  48                 : "memory");
  49 }
  50
  51 static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
  52 {
  53         cpu_boot_addr = boot_addr;
  54         tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, cpu_boot_addr, 0);
  55
  56         return 0;
  57 }
  58
  59 static int tf_prepare_idle(void)
  60 {
  61         tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1_NOFLUSH_L2, cpu_boot_addr);
  62
  63         return 0;
  64 }
  65
  66 static const struct firmware_ops trusted_foundations_ops = {
  67         .set_cpu_boot_addr = tf_set_cpu_boot_addr,
  68         .prepare_idle = tf_prepare_idle,
  69 };
  70
  71 void register_trusted_foundations(struct trusted_foundations_platform_data *pd)
  72 {
  73         /*
  74          * we are not using version information for now since currently
  75          * supported SMCs are compatible with all TF releases
  76          */
  77         register_firmware_ops(&trusted_foundations_ops);
  78 }
  79
  80 void of_register_trusted_foundations(void)
  81 {
  82         struct device_node *node;
  83         struct trusted_foundations_platform_data pdata;
  84         int err;
  85
  86         node = of_find_compatible_node(NULL, NULL, "tlm,trusted-foundations");
  87         if (!node)
  88                 return;
  89
  90         err = of_property_read_u32(node, "tlm,version-major",
  91                                    &pdata.version_major);
  92         if (err != 0)
  93                 panic("Trusted Foundation: missing version-major property\n");
  94         err = of_property_read_u32(node, "tlm,version-minor",
  95                                    &pdata.version_minor);
  96         if (err != 0)
  97                 panic("Trusted Foundation: missing version-minor property\n");
  98         register_trusted_foundations(&pdata);
  99 }