1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2017 lvaro Fernndez Rojas <noltari (at) gmail.com> 4 * 5 * Derived from linux/drivers/watchdog/bcm63xx_wdt.c: 6 * Copyright (C) 2007 Miguel Gaio <miguel.gaio (at) efixo.com> 7 * Copyright (C) 2008 Florian Fainelli <florian (at) openwrt.org> 8 */ 9 10 #include <common.h> 11 #include <dm.h> 12 #include <wdt.h> 13 #include <asm/io.h> 14 15 /* WDT Value register */ 16 #define WDT_VAL_REG 0x0 17 #define WDT_VAL_MIN 0x00000002 18 #define WDT_VAL_MAX 0xfffffffe 19 20 /* WDT Control register */ 21 #define WDT_CTL_REG 0x4 22 #define WDT_CTL_START1_MASK 0x0000ff00 23 #define WDT_CTL_START2_MASK 0x000000ff 24 #define WDT_CTL_STOP1_MASK 0x0000ee00 25 #define WDT_CTL_STOP2_MASK 0x000000ee 26 27 struct bcm6345_wdt_priv { 28 void __iomem *regs; 29 }; 30 31 static int bcm6345_wdt_reset(struct udevice *dev) 32 { 33 struct bcm6345_wdt_priv *priv = dev_get_priv(dev); 34 35 writel_be(WDT_CTL_START1_MASK, priv->regs + WDT_CTL_REG); 36 writel_be(WDT_CTL_START2_MASK, priv->regs + WDT_CTL_REG); 37 38 return 0; 39 } 40 41 static int bcm6345_wdt_start(struct udevice *dev, u64 timeout, ulong flags) 42 { 43 struct bcm6345_wdt_priv *priv = dev_get_priv(dev); 44 45 if (timeout < WDT_VAL_MIN) { 46 debug("watchdog won't fire with less than 2 ticks\n"); 47 timeout = WDT_VAL_MIN; 48 } else if (timeout > WDT_VAL_MAX) { 49 debug("maximum watchdog timeout exceeded\n"); 50 timeout = WDT_VAL_MAX; 51 } 52 53 writel_be(timeout, priv->regs + WDT_VAL_REG); 54 55 return bcm6345_wdt_reset(dev); 56 } 57 58 static int bcm6345_wdt_expire_now(struct udevice *dev, ulong flags) 59 { 60 return bcm6345_wdt_start(dev, WDT_VAL_MIN, flags); 61 } 62 63 static int bcm6345_wdt_stop(struct udevice *dev) 64 { 65 struct bcm6345_wdt_priv *priv = dev_get_priv(dev); 66 67 writel_be(WDT_CTL_STOP1_MASK, priv->regs + WDT_CTL_REG); 68 writel_be(WDT_CTL_STOP2_MASK, priv->regs + WDT_CTL_REG); 69 70 return 0; 71 } 72 73 static const struct wdt_ops bcm6345_wdt_ops = { 74 .expire_now = bcm6345_wdt_expire_now, 75 .reset = bcm6345_wdt_reset, 76 .start = bcm6345_wdt_start, 77 .stop = bcm6345_wdt_stop, 78 }; 79 80 static const struct udevice_id bcm6345_wdt_ids[] = { 81 { .compatible = "brcm,bcm6345-wdt" }, 82 { /* sentinel */ } 83 }; 84 85 static int bcm6345_wdt_probe(struct udevice *dev) 86 { 87 struct bcm6345_wdt_priv *priv = dev_get_priv(dev); 88 89 priv->regs = dev_remap_addr(dev); 90 if (!priv->regs) 91 return -EINVAL; 92 93 bcm6345_wdt_stop(dev); 94 95 return 0; 96 } 97 98 U_BOOT_DRIVER(wdt_bcm6345) = { 99 .name = "wdt_bcm6345", 100 .id = UCLASS_WDT, 101 .of_match = bcm6345_wdt_ids, 102 .ops = &bcm6345_wdt_ops, 103 .priv_auto_alloc_size = sizeof(struct bcm6345_wdt_priv), 104 .probe = bcm6345_wdt_probe, 105 }; 106
