diff options
Diffstat (limited to 'drivers/watchdog/npcm_wdt.c')
-rw-r--r-- | drivers/watchdog/npcm_wdt.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/drivers/watchdog/npcm_wdt.c b/drivers/watchdog/npcm_wdt.c new file mode 100644 index 0000000..256020f --- /dev/null +++ b/drivers/watchdog/npcm_wdt.c @@ -0,0 +1,116 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2022 Nuvoton Technology, Inc + */ + +#include <dm.h> +#include <errno.h> +#include <log.h> +#include <wdt.h> +#include <asm/io.h> +#include <linux/delay.h> +#include <linux/err.h> + +#define NPCM_WTCLK (BIT(10) | BIT(11)) /* Clock divider */ +#define NPCM_WTE BIT(7) /* Enable */ +#define NPCM_WTIE BIT(6) /* Enable irq */ +#define NPCM_WTIS (BIT(4) | BIT(5)) /* Interval selection */ +#define NPCM_WTIF BIT(3) /* Interrupt flag*/ +#define NPCM_WTRF BIT(2) /* Reset flag */ +#define NPCM_WTRE BIT(1) /* Reset enable */ +#define NPCM_WTR BIT(0) /* Reset counter */ + +struct npcm_wdt_priv { + void __iomem *regs; +}; + +static int npcm_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags) +{ + struct npcm_wdt_priv *priv = dev_get_priv(dev); + u32 time_out, val; + + time_out = (u32)(timeout_ms) / 1000; + if (time_out < 2) + val = 0x800; + else if (time_out < 3) + val = 0x420; + else if (time_out < 6) + val = 0x810; + else if (time_out < 11) + val = 0x430; + else if (time_out < 22) + val = 0x820; + else if (time_out < 44) + val = 0xc00; + else if (time_out < 87) + val = 0x830; + else if (time_out < 173) + val = 0xc10; + else if (time_out < 688) + val = 0xc20; + else + val = 0xc30; + + val |= NPCM_WTRE | NPCM_WTE | NPCM_WTR | NPCM_WTIE; + writel(val, priv->regs); + + return 0; +} + +static int npcm_wdt_stop(struct udevice *dev) +{ + struct npcm_wdt_priv *priv = dev_get_priv(dev); + + writel(0, priv->regs); + + return 0; +} + +static int npcm_wdt_reset(struct udevice *dev) +{ + struct npcm_wdt_priv *priv = dev_get_priv(dev); + + writel(NPCM_WTR | NPCM_WTRE | NPCM_WTE, priv->regs); + + return 0; +} + +static int npcm_wdt_of_to_plat(struct udevice *dev) +{ + struct npcm_wdt_priv *priv = dev_get_priv(dev); + + priv->regs = dev_read_addr_ptr(dev); + if (!priv->regs) + return -EINVAL; + + return 0; +} + +static const struct wdt_ops npcm_wdt_ops = { + .start = npcm_wdt_start, + .reset = npcm_wdt_reset, + .stop = npcm_wdt_stop, +}; + +static const struct udevice_id npcm_wdt_ids[] = { + { .compatible = "nuvoton,npcm750-wdt" }, + { } +}; + +static int npcm_wdt_probe(struct udevice *dev) +{ + debug("%s() wdt%u\n", __func__, dev_seq(dev)); + npcm_wdt_stop(dev); + + return 0; +} + +U_BOOT_DRIVER(npcm_wdt) = { + .name = "npcm_wdt", + .id = UCLASS_WDT, + .of_match = npcm_wdt_ids, + .probe = npcm_wdt_probe, + .priv_auto = sizeof(struct npcm_wdt_priv), + .of_to_plat = npcm_wdt_of_to_plat, + .ops = &npcm_wdt_ops, +}; |