pinebuds/platform/hal/hal_wdt.c

/***************************************************************************
 *
 * Copyright 2015-2019 BES.
 * All rights reserved. All unpublished rights reserved.
 *
 * No part of this work may be used or reproduced in any form or by any
 * means, or stored in a database or retrieval system, without prior written
 * permission of BES.
 *
 * Use of this work is governed by a license granted by BES.
 * This work contains confidential and proprietary information of
 * BES. which is protected by copyright, trade secret,
 * trademark and other intellectual property rights.
 *
 ****************************************************************************/
#include "hal_wdt.h"
#include "cmsis.h"
#include "cmsis_nvic.h"
#include "hal_timer.h"
#include "hal_trace.h"
#include "hal_uart.h"
#include "plat_addr_map.h"
#include "plat_types.h"

#if defined(CHIP_BEST3001) || defined(CHIP_BEST3003) ||                        \
    defined(CHIP_BEST3005) || defined(CHIP_BEST1400) || defined(CHIP_BEST1402)
#define CLOCK_SYNC_WORKAROUND
#endif

#define SLOW_TIMER_VAL_DELTA 1
#define FAST_TIMER_VAL_DELTA 20

/* wdt controller */
/* reg address */
/* default timeout in seconds */
#define DEFAULT_TIMEOUT 60

#define WDT_RATE CONFIG_SYSTICK_HZ

/* watchdog register offsets and masks */
#define WDTLOAD_REG_OFFSET 0x000
#define WDTLOAD_LOAD_MIN 0x00000001
#define WDTLOAD_LOAD_MAX 0xFFFFFFFF

#define WDTVALUE_REG_OFFSET 0x004

#define WDTCONTROL_REG_OFFSET 0x008
#define WDTCONTROL_REG_INT_ENABLE (1 << 0)
#define WDTCONTROL_REG_RESET_ENABLE (1 << 1)

#define WDTINTCLR_REG_OFFSET 0x00C

#define WDTRIS_REG_OFFSET 0x010
#define WDTRIS_REG_INT_MASK (1 << 0)

#define WDTMIS_REG_OFFSET 0x014
#define WDTMIS_REG_INT_MASK (1 << 0)

#define WDTLOCK_REG_OFFSET 0xC00
#define WDTLOCK_REG_UNLOCK 0x1ACCE551
#define WDTLOCK_REG_LOCK 0x00000001

/* read write */
#define wdtip_write32(v, b, a) (*((volatile unsigned int *)(b + a)) = v)
#define wdtip_read32(b, a) (*((volatile unsigned int *)(b + a)))

#if 1
typedef void (*HAL_WDT_IRQ_HANDLER)(void);

struct HAL_WDT_CTX {
  unsigned int load_val;
};

struct HAL_WDT_CTX hal_wdt_ctx[HAL_WDT_ID_NUM];
static void _wdt1_irq_handler(void);
HAL_WDT_IRQ_HANDLER hal_wdt_irq_handler[HAL_WDT_ID_NUM] = {
    _wdt1_irq_handler,
};
HAL_WDT_IRQ_CALLBACK hal_wdt_irq_callback[HAL_WDT_ID_NUM];

static void _wdt1_irq_handler(void) {
  if (hal_wdt_irq_callback[HAL_WDT_ID_0] != 0) {
    hal_wdt_irq_callback[HAL_WDT_ID_0](HAL_WDT_ID_0, HAL_WDT_EVENT_FIRE);
  }
}

static unsigned int _wdt_get_base(enum HAL_WDT_ID_T id) {
  switch (id) {
  default:
  case HAL_WDT_ID_0:
    return WDT_BASE;
    break;
  }

  return 0;
}

static void _wdt_load(enum HAL_WDT_ID_T id) {
  unsigned int reg_base = 0;
  struct HAL_WDT_CTX *wdt = &hal_wdt_ctx[id];
  uint32_t lock;

  reg_base = _wdt_get_base(id);

  lock = int_lock();

  wdtip_write32(WDTLOCK_REG_UNLOCK, reg_base, WDTLOCK_REG_OFFSET);

#ifdef CLOCK_SYNC_WORKAROUND
  uint32_t val;

  do {
    wdtip_write32(wdt->load_val, reg_base, WDTLOAD_REG_OFFSET);
    val = wdtip_read32(reg_base, WDTVALUE_REG_OFFSET);
  } while ((wdt->load_val < val) ||
           (wdt->load_val > val + SLOW_TIMER_VAL_DELTA));
#else
  wdtip_write32(wdt->load_val, reg_base, WDTLOAD_REG_OFFSET);
#endif

  wdtip_write32(WDTLOCK_REG_LOCK, reg_base, WDTLOCK_REG_OFFSET);

  int_unlock(lock);

  /* Flush posted writes. */
  wdtip_read32(reg_base, WDTLOCK_REG_OFFSET);
}

static void _wdt_config(enum HAL_WDT_ID_T id) {
  unsigned int reg_base = 0;
  uint32_t lock;

  reg_base = _wdt_get_base(id);

  lock = int_lock();
  wdtip_write32(WDTLOCK_REG_UNLOCK, reg_base, WDTLOCK_REG_OFFSET);
  wdtip_write32(WDTRIS_REG_INT_MASK, reg_base, WDTINTCLR_REG_OFFSET);
  wdtip_write32(WDTCONTROL_REG_INT_ENABLE | WDTCONTROL_REG_RESET_ENABLE,
                reg_base, WDTCONTROL_REG_OFFSET);
  wdtip_write32(WDTLOCK_REG_LOCK, reg_base, WDTLOCK_REG_OFFSET);
  int_unlock(lock);

  /* Flush posted writes. */
  wdtip_read32(reg_base, WDTLOCK_REG_OFFSET);
}

static int wdt_start;

/* mandatory operations */
int hal_wdt_start(enum HAL_WDT_ID_T id) {
  _wdt_load(id);
  _wdt_config(id);
  wdt_start = 1;
  return 0;
}
int hal_wdt_stop(enum HAL_WDT_ID_T id) {
  unsigned int reg_base = 0;
  uint32_t lock;

  reg_base = _wdt_get_base(id);

  lock = int_lock();
  wdtip_write32(WDTLOCK_REG_UNLOCK, reg_base, WDTLOCK_REG_OFFSET);
  wdtip_write32(0, reg_base, WDTCONTROL_REG_OFFSET);
  wdtip_write32(WDTLOCK_REG_LOCK, reg_base, WDTLOCK_REG_OFFSET);
  int_unlock(lock);

  /* Flush posted writes. */
  wdtip_read32(reg_base, WDTLOCK_REG_OFFSET);

  wdt_start = 0;
  return 0;
}

/* optional operations */
int hal_wdt_ping(enum HAL_WDT_ID_T id) {
  if (wdt_start) {
    _wdt_load(id);
  }

  return 0;
}
int hal_wdt_set_timeout(enum HAL_WDT_ID_T id, unsigned int timeout) {
  uint64_t load;
  struct HAL_WDT_CTX *wdt = &hal_wdt_ctx[id];

  /*
   * sp805 runs counter with given value twice, after the end of first
   * counter it gives an interrupt and then starts counter again. If
   * interrupt already occurred then it resets the system. This is why
   * load is half of what should be required.
   */
  load = WDT_RATE * timeout - 1;

  load = (load > WDTLOAD_LOAD_MAX) ? WDTLOAD_LOAD_MAX : load;
  load = (load < WDTLOAD_LOAD_MIN) ? WDTLOAD_LOAD_MIN : load;

  wdt->load_val = load;

  return 0;
}
unsigned int hal_wdt_get_timeleft(enum HAL_WDT_ID_T id) {
  uint64_t load;
  unsigned int reg_base = 0;
  struct HAL_WDT_CTX *wdt = &hal_wdt_ctx[id];

  reg_base = _wdt_get_base(id);

  load = wdtip_read32(reg_base, WDTVALUE_REG_OFFSET);

  /*If the interrupt is inactive then time left is WDTValue + WDTLoad. */
  if (!(wdtip_read32(reg_base, WDTRIS_REG_OFFSET) & WDTRIS_REG_INT_MASK))
    load += wdt->load_val + 1;

  return load / WDT_RATE;
}

void hal_wdt_set_irq_callback(enum HAL_WDT_ID_T id, HAL_WDT_IRQ_CALLBACK cb) {
  switch (id) {
  default:
  case HAL_WDT_ID_0:
    NVIC_SetVector(WDT_IRQn, (uint32_t)hal_wdt_irq_handler[id]);
    NVIC_SetPriority(WDT_IRQn, IRQ_PRIORITY_NORMAL);
    NVIC_ClearPendingIRQ(WDT_IRQn);
    NVIC_EnableIRQ(WDT_IRQn);
    break;
  }

  hal_wdt_irq_callback[id] = cb;
}

#endif