LXR uboot/drivers/watchdog/ast2600

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (c) 2020 Aspeed Technology, Inc
   4 */
   5
   6#include <common.h>
   7#include <dm.h>
   8#include <errno.h>
   9#include <log.h>
  10#include <wdt.h>
  11#include <asm/io.h>
  12#include <asm/arch/wdt_ast2600.h>
  13#include <linux/err.h>
  14
  15struct ast2600_wdt_priv {
  16        struct ast2600_wdt *regs;
  17};
  18
  19static int ast2600_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
  20{
  21        struct ast2600_wdt_priv *priv = dev_get_priv(dev);
  22        struct ast2600_wdt *wdt = priv->regs;
  23
  24        /* WDT counts in the 1MHz frequency, namely 1us */
  25        writel((u32)(timeout_ms * 1000), &wdt->counter_reload_val);
  26        writel(WDT_COUNTER_RESTART_VAL, &wdt->counter_restart);
  27        writel(WDT_CTRL_EN | WDT_CTRL_RESET, &wdt->ctrl);
  28
  29        return 0;
  30}
  31
  32static int ast2600_wdt_stop(struct udevice *dev)
  33{
  34        struct ast2600_wdt_priv *priv = dev_get_priv(dev);
  35        struct ast2600_wdt *wdt = priv->regs;
  36
  37        clrbits_le32(&wdt->ctrl, WDT_CTRL_EN);
  38
  39        writel(WDT_RESET_MASK1_DEFAULT, &wdt->reset_mask1);
  40        writel(WDT_RESET_MASK2_DEFAULT, &wdt->reset_mask2);
  41
  42        return 0;
  43}
  44
  45static int ast2600_wdt_reset(struct udevice *dev)
  46{
  47        struct ast2600_wdt_priv *priv = dev_get_priv(dev);
  48        struct ast2600_wdt *wdt = priv->regs;
  49
  50        writel(WDT_COUNTER_RESTART_VAL, &wdt->counter_restart);
  51
  52        return 0;
  53}
  54
  55static int ast2600_wdt_expire_now(struct udevice *dev, ulong flags)
  56{
  57        int ret;
  58        struct ast2600_wdt_priv *priv = dev_get_priv(dev);
  59        struct ast2600_wdt *wdt = priv->regs;
  60
  61        ret = ast2600_wdt_start(dev, 1, flags);
  62        if (ret)
  63                return ret;
  64
  65        while (readl(&wdt->ctrl) & WDT_CTRL_EN)
  66                ;
  67
  68        return ast2600_wdt_stop(dev);
  69}
  70
  71static int ast2600_wdt_of_to_plat(struct udevice *dev)
  72{
  73        struct ast2600_wdt_priv *priv = dev_get_priv(dev);
  74
  75        priv->regs = dev_read_addr_ptr(dev);
  76        if (!priv->regs)
  77                return -EINVAL;
  78
  79        return 0;
  80}
  81
  82static const struct wdt_ops ast2600_wdt_ops = {
  83        .start = ast2600_wdt_start,
  84        .reset = ast2600_wdt_reset,
  85        .stop = ast2600_wdt_stop,
  86        .expire_now = ast2600_wdt_expire_now,
  87};
  88
  89static const struct udevice_id ast2600_wdt_ids[] = {
  90        { .compatible = "aspeed,ast2600-wdt" },
  91        { }
  92};
  93
  94static int ast2600_wdt_probe(struct udevice *dev)
  95{
  96        debug("%s() wdt%u\n", __func__, dev_seq(dev));
  97        ast2600_wdt_stop(dev);
  98
  99        return 0;
 100}
 101
 102U_BOOT_DRIVER(ast2600_wdt) = {
 103        .name = "ast2600_wdt",
 104        .id = UCLASS_WDT,
 105        .of_match = ast2600_wdt_ids,
 106        .probe = ast2600_wdt_probe,
 107        .priv_auto = sizeof(struct ast2600_wdt_priv),
 108        .of_to_plat = ast2600_wdt_of_to_plat,
 109        .ops = &ast2600_wdt_ops,
 110};
 111