Quelle  trusted_foundations.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Trusted Foundations support for ARM CPUs
 *
 * Copyright (c) 2013, NVIDIA Corporation.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of.h>

#include <linux/firmware/trusted_foundations.h>

#include <asm/firmware.h>
#include <asm/hardware/cache-l2x0.h>
#include <asm/outercache.h>

#define TF_CACHE_MAINT  0xfffff100

#define TF_CACHE_ENABLE  1
#define TF_CACHE_DISABLE 2
#define TF_CACHE_REENABLE 4

#define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200

#define TF_CPU_PM  0xfffffffc
#define TF_CPU_PM_S3  0xffffffe3
#define TF_CPU_PM_S2  0xffffffe6
#define TF_CPU_PM_S2_NO_MC_CLK 0xffffffe5
#define TF_CPU_PM_S1  0xffffffe4
#define TF_CPU_PM_S1_NOFLUSH_L2 0xffffffe7

static unsigned long tf_idle_mode = TF_PM_MODE_NONE;
static unsigned long cpu_boot_addr;

static void tf_generic_smc(u32 type, u32 arg1, u32 arg2)
{
 register u32 r0 asm("r0") = type;
 register u32 r1 asm("r1") = arg1;
 register u32 r2 asm("r2") = arg2;

 asm volatile(
  ".arch_extension sec\n\t"
  "stmfd sp!, {r4 - r11}\n\t"
  __asmeq("%0", "r0")
  __asmeq("%1", "r1")
  __asmeq("%2", "r2")
  "mov r3, #0\n\t"
  "mov r4, #0\n\t"
  "smc #0\n\t"
  "ldmfd sp!, {r4 - r11}\n\t"
  :
  : "r" (r0), "r" (r1), "r" (r2)
  : "memory", "r3", "r12", "lr");
}

static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
{
 cpu_boot_addr = boot_addr;
 tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, cpu_boot_addr, 0);

 return 0;
}

static int tf_prepare_idle(unsigned long mode)
{
 switch (mode) {
 case TF_PM_MODE_LP0:
  tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S3, cpu_boot_addr);
  break;

 case TF_PM_MODE_LP1:
  tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S2, cpu_boot_addr);
  break;

 case TF_PM_MODE_LP1_NO_MC_CLK:
  tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S2_NO_MC_CLK,
          cpu_boot_addr);
  break;

 case TF_PM_MODE_LP2:
  tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1, cpu_boot_addr);
  break;

 case TF_PM_MODE_LP2_NOFLUSH_L2:
  tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1_NOFLUSH_L2,
          cpu_boot_addr);
  break;

 case TF_PM_MODE_NONE:
  break;

 default:
  return -EINVAL;
 }

 tf_idle_mode = mode;

 return 0;
}

#ifdef CONFIG_CACHE_L2X0
static void tf_cache_write_sec(unsigned long val, unsigned int reg)
{
 u32 enable_op, l2x0_way_mask = 0xff;

 switch (reg) {
 case L2X0_CTRL:
  if (l2x0_saved_regs.aux_ctrl & L310_AUX_CTRL_ASSOCIATIVITY_16)
   l2x0_way_mask = 0xffff;

  switch (tf_idle_mode) {
  case TF_PM_MODE_LP2:
   enable_op = TF_CACHE_REENABLE;
   break;

  default:
   enable_op = TF_CACHE_ENABLE;
   break;
  }

  if (val == L2X0_CTRL_EN)
   tf_generic_smc(TF_CACHE_MAINT, enable_op,
           l2x0_saved_regs.aux_ctrl);
  else
   tf_generic_smc(TF_CACHE_MAINT, TF_CACHE_DISABLE,
           l2x0_way_mask);
  break;

 default:
  break;
 }
}

static int tf_init_cache(void)
{
 outer_cache.write_sec = tf_cache_write_sec;

 return 0;
}
#endif /* CONFIG_CACHE_L2X0 */

static const struct firmware_ops trusted_foundations_ops = {
 .set_cpu_boot_addr = tf_set_cpu_boot_addr,
 .prepare_idle = tf_prepare_idle,
#ifdef CONFIG_CACHE_L2X0
 .l2x0_init = tf_init_cache,
#endif
};

void register_trusted_foundations(struct trusted_foundations_platform_data *pd)
{
 /*
 * we are not using version information for now since currently
 * supported SMCs are compatible with all TF releases
 */
 register_firmware_ops(&trusted_foundations_ops);
}

void of_register_trusted_foundations(void)
{
 struct device_node *node;
 struct trusted_foundations_platform_data pdata;
 int err;

 node = of_find_compatible_node(NULL, NULL, "tlm,trusted-foundations");
 if (!node)
  return;

 err = of_property_read_u32(node, "tlm,version-major",
       &pdata.version_major);
 if (err != 0)
  panic("Trusted Foundation: missing version-major property\n");
 err = of_property_read_u32(node, "tlm,version-minor",
       &pdata.version_minor);
 if (err != 0)
  panic("Trusted Foundation: missing version-minor property\n");
 register_trusted_foundations(&pdata);
}

bool trusted_foundations_registered(void)
{
 return firmware_ops == &trusted_foundations_ops;
}