From 0652d9fb1a5c5fbe962e7e581031acd39672738f Mon Sep 17 00:00:00 2001 From: Qiang Zhao Date: Tue, 7 May 2019 03:16:09 +0000 Subject: [PATCH] driver: watchdog: add sp805 watchdog support sp805 is watchdog on some NXP layerscape SoCs, adding it's driver. Configs CONFIG_WDT_SP805, CONFIG_WDT, CONFIG_CMD_WDT needs to be enabled to use it. Signed-off-by: Zhao Qiang Reviewed-by: Prabhakar Kushwaha --- MAINTAINERS | 1 + drivers/watchdog/Kconfig | 7 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/sp805_wdt.c | 127 +++++++++++++++++++++++++++++++++++ 4 files changed, 136 insertions(+) create mode 100644 drivers/watchdog/sp805_wdt.c diff --git a/MAINTAINERS b/MAINTAINERS index c41bc89fe9..36625795a4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -519,6 +519,7 @@ FREESCALE QORIQ M: Prabhakar Kushwaha S: Maintained T: git git://git.denx.de/u-boot-fsl-qoriq.git +F: drivers/watchdog/sp805_wdt.c I2C M: Heiko Schocher diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index f909d40f45..b01dbc446d 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -103,6 +103,13 @@ config WDT_ORION Select this to enable Orion watchdog timer, which can be found on some Marvell Armada chips. +config WDT_SP805 + bool "SP805 watchdog timer support" + depends on WDT + help + Select this to enable SP805 watchdog timer, which can be found on some + nxp layerscape chips. + config WDT_CDNS bool "Cadence watchdog timer support" depends on WDT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 40b2f4bc66..6f20e73810 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -27,3 +27,4 @@ obj-$(CONFIG_WDT_CDNS) += cdns_wdt.o obj-$(CONFIG_WDT_MPC8xx) += mpc8xx_wdt.o obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o obj-$(CONFIG_WDT_MTK) += mtk_wdt.o +obj-$(CONFIG_WDT_SP805) += sp805_wdt.o diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c new file mode 100644 index 0000000000..966128216f --- /dev/null +++ b/drivers/watchdog/sp805_wdt.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Watchdog driver for SP805 on some Layerscape SoC + * + * Copyright 2019 NXP + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define WDTLOAD 0x000 +#define WDTCONTROL 0x008 +#define WDTINTCLR 0x00C +#define WDTLOCK 0xC00 + +#define TIME_OUT_MIN_MSECS 1 +#define TIME_OUT_MAX_MSECS 120000 +#define SYS_FSL_WDT_CLK_DIV 16 +#define INT_ENABLE BIT(0) +#define RESET_ENABLE BIT(1) +#define DISABLE 0 +#define UNLOCK 0x1ACCE551 +#define LOCK 0x00000001 +#define INT_MASK BIT(0) + +DECLARE_GLOBAL_DATA_PTR; + +struct sp805_wdt_priv { + void __iomem *reg; +}; + +static int sp805_wdt_reset(struct udevice *dev) +{ + struct sp805_wdt_priv *priv = dev_get_priv(dev); + + writel(UNLOCK, priv->reg + WDTLOCK); + writel(INT_MASK, priv->reg + WDTINTCLR); + writel(LOCK, priv->reg + WDTLOCK); + readl(priv->reg + WDTLOCK); + + return 0; +} + +static int sp805_wdt_start(struct udevice *dev, u64 timeout, ulong flags) +{ + u32 load_value; + u32 load_time; + struct sp805_wdt_priv *priv = dev_get_priv(dev); + + load_time = (u32)timeout; + if (timeout < TIME_OUT_MIN_MSECS) + load_time = TIME_OUT_MIN_MSECS; + else if (timeout > TIME_OUT_MAX_MSECS) + load_time = TIME_OUT_MAX_MSECS; + /* sp805 runs counter with given value twice, so when the max timeout is + * set 120s, the gd->bus_clk is less than 1145MHz, the load_value will + * not overflow. + */ + load_value = (gd->bus_clk) / + (2 * 1000 * SYS_FSL_WDT_CLK_DIV) * load_time; + + writel(UNLOCK, priv->reg + WDTLOCK); + writel(load_value, priv->reg + WDTLOAD); + writel(INT_MASK, priv->reg + WDTINTCLR); + writel(INT_ENABLE | RESET_ENABLE, priv->reg + WDTCONTROL); + writel(LOCK, priv->reg + WDTLOCK); + readl(priv->reg + WDTLOCK); + + return 0; +} + +static int sp805_wdt_stop(struct udevice *dev) +{ + struct sp805_wdt_priv *priv = dev_get_priv(dev); + + writel(UNLOCK, priv->reg + WDTLOCK); + writel(DISABLE, priv->reg + WDTCONTROL); + writel(LOCK, priv->reg + WDTLOCK); + readl(priv->reg + WDTLOCK); + + return 0; +} + +static int sp805_wdt_probe(struct udevice *dev) +{ + debug("%s: Probing wdt%u\n", __func__, dev->seq); + + return 0; +} + +static int sp805_wdt_ofdata_to_platdata(struct udevice *dev) +{ + struct sp805_wdt_priv *priv = dev_get_priv(dev); + + priv->reg = (void __iomem *)dev_read_addr(dev); + if (IS_ERR(priv->reg)) + return PTR_ERR(priv->reg); + + return 0; +} + +static const struct wdt_ops sp805_wdt_ops = { + .start = sp805_wdt_start, + .reset = sp805_wdt_reset, + .stop = sp805_wdt_stop, +}; + +static const struct udevice_id sp805_wdt_ids[] = { + { .compatible = "arm,sp805-wdt" }, + {} +}; + +U_BOOT_DRIVER(sp805_wdt) = { + .name = "sp805_wdt", + .id = UCLASS_WDT, + .of_match = sp805_wdt_ids, + .probe = sp805_wdt_probe, + .priv_auto_alloc_size = sizeof(struct sp805_wdt_priv), + .ofdata_to_platdata = sp805_wdt_ofdata_to_platdata, + .ops = &sp805_wdt_ops, +}; -- 2.25.1