git.sur5r.net Git - u-boot/blob - drivers/watchdog/tangier_wdt.c

   1 /*
   2  * Copyright (c) 2017 Intel Corporation
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6 #include <common.h>
   7 #include <watchdog.h>
   8 #include <asm/scu.h>
   9
  10 /* Hardware timeout in seconds */
  11 #define WDT_PRETIMEOUT          15
  12 #define WDT_TIMEOUT_MIN         (1 + WDT_PRETIMEOUT)
  13 #define WDT_TIMEOUT_MAX         170
  14 #define WDT_DEFAULT_TIMEOUT     90
  15
  16 #ifndef CONFIG_WATCHDOG_TIMEOUT_MSECS
  17 #define WATCHDOG_HEARTBEAT 60000
  18 #else
  19 #define WATCHDOG_HEARTBEAT CONFIG_WATCHDOG_TIMEOUT_MSECS
  20 #endif
  21
  22 enum {
  23         SCU_WATCHDOG_START                      = 0,
  24         SCU_WATCHDOG_STOP                       = 1,
  25         SCU_WATCHDOG_KEEPALIVE                  = 2,
  26         SCU_WATCHDOG_SET_ACTION_ON_TIMEOUT      = 3,
  27 };
  28
  29 void hw_watchdog_reset(void)
  30 {
  31         static unsigned long last;
  32         unsigned long now;
  33
  34         if (gd->timer)
  35                 now = timer_get_us();
  36         else
  37                 now = rdtsc() / 1000;
  38
  39         /* Do not flood SCU */
  40         if (last > now)
  41                 last = 0;
  42
  43         if (unlikely((now - last) > (WDT_PRETIMEOUT / 2) * 1000000)) {
  44                 last = now;
  45                 scu_ipc_simple_command(IPCMSG_WATCHDOG_TIMER, SCU_WATCHDOG_KEEPALIVE);
  46         }
  47 }
  48
  49 int hw_watchdog_disable(void)
  50 {
  51         return scu_ipc_simple_command(IPCMSG_WATCHDOG_TIMER, SCU_WATCHDOG_STOP);
  52 }
  53
  54 void hw_watchdog_init(void)
  55 {
  56         u32 timeout = WATCHDOG_HEARTBEAT / 1000;
  57         int in_size;
  58         struct ipc_wd_start {
  59                 u32 pretimeout;
  60                 u32 timeout;
  61         } ipc_wd_start = { timeout - WDT_PRETIMEOUT, timeout };
  62
  63         /*
  64          * SCU expects the input size for watchdog IPC
  65          * to be based on 4 bytes
  66          */
  67         in_size = DIV_ROUND_UP(sizeof(ipc_wd_start), 4);
  68
  69         scu_ipc_command(IPCMSG_WATCHDOG_TIMER, SCU_WATCHDOG_START,
  70                         (u32 *)&ipc_wd_start, in_size, NULL, 0);
  71 }