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katsustergalak
katsuster
authored and
galak
committed
drivers: watchdog: implement SiFive FE310 watchdog driver
This patch adds watchdog driver for HiFive1 rev.B that has SiFive Freedom E310 SoC. Signed-off-by: Katsuhiro Suzuki <[email protected]>
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‎CODEOWNERS

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@@ -292,6 +292,7 @@
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/drivers/i2c/i2c_dw* @dcpleung
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/drivers/*/*xec* @franciscomunoz @albertofloyd @scottwcpg
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/drivers/watchdog/*gecko* @oanerer
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/drivers/watchdog/*sifive* @katsuster
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/drivers/watchdog/wdt_handlers.c @andrewboie
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/drivers/wifi/ @jukkar @tbursztyka @pfalcon
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/drivers/wifi/esp/ @mniestroj

‎drivers/watchdog/CMakeLists.txt

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@@ -13,4 +13,5 @@ zephyr_sources_ifdef(CONFIG_WDT_MCUX_WDOG32 wdt_mcux_wdog32.c)
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zephyr_sources_ifdef(CONFIG_WDT_MCUX_WWDT wdt_mcux_wwdt.c)
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zephyr_sources_ifdef(CONFIG_WDT_XEC wdt_mchp_xec.c)
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zephyr_sources_ifdef(CONFIG_WDT_GECKO wdt_gecko.c)
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zephyr_sources_ifdef(CONFIG_WDT_SIFIVE wdt_sifive.c)
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zephyr_sources_ifdef(CONFIG_USERSPACE wdt_handlers.c)

‎drivers/watchdog/Kconfig

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@@ -50,4 +50,6 @@ source "drivers/watchdog/Kconfig.xec"
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source "drivers/watchdog/Kconfig.gecko"
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source "drivers/watchdog/Kconfig.sifive"
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endif

‎drivers/watchdog/Kconfig.sifive

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# SiFive Freedom WDT configuration
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# Copyright (C) 2020 Katsuhiro Suzuki
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# SPDX-License-Identifier: Apache-2.0
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config WDT_SIFIVE
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bool "SiFive Watchdog (WDT) Driver"
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depends on SOC_RISCV_SIFIVE_FREEDOM
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default y
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help
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This option enables WDT driver for SiFive Freedom.

‎drivers/watchdog/wdt_sifive.c

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/*
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* Copyright (C) 2020 Katsuhiro Suzuki
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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/**
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* @brief Watchdog (WDT) Driver for SiFive Freedom
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*/
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#define DT_DRV_COMPAT sifive_wdt
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#include <kernel.h>
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#include <soc.h>
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#include <drivers/watchdog.h>
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#define LOG_LEVEL CONFIG_WDT_LOG_LEVEL
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#include <logging/log.h>
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LOG_MODULE_REGISTER(wdt_sifive);
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#define WDOGCFG_SCALE_MAX 0xf
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#define WDOGCFG_SCALE_SHIFT 0
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#define WDOGCFG_SCALE_MASK (WDOGCFG_SCALE_MAX << WDOGCFG_SCALE_SHIFT)
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#define WDOGCFG_RSTEN BIT(8)
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#define WDOGCFG_ZEROCMP BIT(9)
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#define WDOGCFG_ENALWAYS BIT(12)
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#define WDOGCFG_COREAWAKE BIT(13)
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#define WDOGCFG_IP0 BIT(28)
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#define WDOGCMP_MAX 0xffff
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#define WDOG_KEY 0x51f15e
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#define WDOG_FEED 0xd09f00d
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#define WDOG_CLK 32768
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struct wdt_sifive_reg {
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/* offset: 0x000 */
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uint32_t wdogcfg;
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uint32_t dummy0;
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uint32_t wdogcount;
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uint32_t dummy1;
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/* offset: 0x010 */
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uint32_t wdogs;
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uint32_t dummy2;
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uint32_t wdogfeed;
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uint32_t wdogkey;
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/* offset: 0x020 */
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uint32_t wdogcmp0;
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};
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struct wdt_sifive_device_config {
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uintptr_t regs;
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};
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struct wdt_sifive_dev_data {
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wdt_callback_t cb;
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bool enable_cb;
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bool timeout_valid;
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};
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#define DEV_CFG(dev) \
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((const struct wdt_sifive_device_config *const)(dev)->config)
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#define DEV_REG(dev) \
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((struct wdt_sifive_reg *)(DEV_CFG(dev))->regs)
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/**
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* @brief Set maximum length of timeout to watchdog
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*
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* @param dev Watchdog device struct
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*/
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static void wdt_sifive_set_max_timeout(const struct device *dev)
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{
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volatile struct wdt_sifive_reg *wdt = DEV_REG(dev);
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uint32_t t;
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t = wdt->wdogcfg;
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t |= WDOGCFG_SCALE_MASK;
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wdt->wdogkey = WDOG_KEY;
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wdt->wdogcfg = t;
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wdt->wdogkey = WDOG_KEY;
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wdt->wdogcmp0 = WDOGCMP_MAX;
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}
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static void wdt_sifive_isr(const struct device *dev)
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{
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volatile struct wdt_sifive_reg *wdt = DEV_REG(dev);
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struct wdt_sifive_dev_data *data = dev->data;
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uint32_t t;
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wdt_sifive_set_max_timeout(dev);
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t = wdt->wdogcfg;
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t &= ~WDOGCFG_IP0;
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wdt->wdogkey = WDOG_KEY;
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wdt->wdogcfg = t;
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if (data->enable_cb && data->cb) {
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data->enable_cb = false;
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data->cb(dev, 0);
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}
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}
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static int wdt_sifive_disable(const struct device *dev)
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{
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struct wdt_sifive_dev_data *data = dev->data;
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wdt_sifive_set_max_timeout(dev);
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data->enable_cb = false;
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return 0;
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}
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static int wdt_sifive_setup(const struct device *dev, uint8_t options)
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{
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volatile struct wdt_sifive_reg *wdt = DEV_REG(dev);
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struct wdt_sifive_dev_data *data = dev->data;
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uint32_t t, mode;
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if (!data->timeout_valid) {
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LOG_ERR("No valid timeouts installed");
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return -EINVAL;
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}
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mode = WDOGCFG_ENALWAYS;
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if ((options & WDT_OPT_PAUSE_IN_SLEEP) ==
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WDT_OPT_PAUSE_IN_SLEEP) {
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mode = WDOGCFG_COREAWAKE;
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}
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if ((options & WDT_OPT_PAUSE_HALTED_BY_DBG) ==
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WDT_OPT_PAUSE_HALTED_BY_DBG) {
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mode = WDOGCFG_COREAWAKE;
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}
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t = wdt->wdogcfg;
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t &= ~(WDOGCFG_ENALWAYS | WDOGCFG_COREAWAKE);
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t |= mode;
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wdt->wdogkey = WDOG_KEY;
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wdt->wdogcfg = t;
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return 0;
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}
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/**
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* @brief Calculates the watchdog counter value (wdogcmp0) and
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* scaler (wdogscale) to be installed in the watchdog timer
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*
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* @param timeout Timeout value in milliseconds.
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* @param clk Clock of watchdog in Hz.
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* @param scaler Pointer to return scaler power of 2
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*
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* @return Watchdog counter value
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*/
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static int wdt_sifive_convtime(uint32_t timeout, int clk, int *scaler)
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{
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uint64_t cnt;
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int i;
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cnt = (uint64_t)timeout * clk / 1000;
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for (i = 0; i < 16; i++) {
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if (cnt <= WDOGCMP_MAX) {
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break;
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}
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cnt >>= 1;
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}
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if (i == 16) {
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/* Maximum counter and scaler */
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LOG_ERR("Invalid timeout value allowed range");
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*scaler = WDOGCFG_SCALE_MAX;
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return WDOGCMP_MAX;
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}
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*scaler = i;
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return cnt;
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}
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static int wdt_sifive_install_timeout(const struct device *dev,
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const struct wdt_timeout_cfg *cfg)
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{
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volatile struct wdt_sifive_reg *wdt = DEV_REG(dev);
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struct wdt_sifive_dev_data *data = dev->data;
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uint32_t mode = 0, t;
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int cmp, scaler;
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if (data->timeout_valid) {
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LOG_ERR("No more timeouts can be installed");
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return -ENOMEM;
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}
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if (cfg->window.min != 0U || cfg->window.max == 0U) {
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return -EINVAL;
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}
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/*
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* Freedom watchdog does not support window timeout config.
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* So use max field of window.
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*/
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cmp = wdt_sifive_convtime(cfg->window.max, WDOG_CLK, &scaler);
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if (cmp < 0 || WDOGCMP_MAX < cmp) {
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LOG_ERR("Unsupported watchdog timeout\n");
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return -EINVAL;
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}
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switch (cfg->flags) {
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case WDT_FLAG_RESET_SOC:
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/* WDT supports global SoC reset but cannot callback. */
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mode = WDOGCFG_RSTEN | WDOGCFG_ZEROCMP;
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break;
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case WDT_FLAG_RESET_NONE:
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/* No reset */
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mode = WDOGCFG_ZEROCMP;
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break;
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case WDT_FLAG_RESET_CPU_CORE:
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default:
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LOG_ERR("Unsupported watchdog config flags\n");
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wdt_sifive_disable(dev);
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return -ENOTSUP;
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}
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t = wdt->wdogcfg;
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t &= ~(WDOGCFG_RSTEN | WDOGCFG_ZEROCMP | WDOGCFG_SCALE_MASK);
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t |= mode | scaler;
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wdt->wdogkey = WDOG_KEY;
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wdt->wdogcfg = t;
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wdt->wdogkey = WDOG_KEY;
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wdt->wdogcmp0 = cmp;
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data->cb = cfg->callback;
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data->enable_cb = true;
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data->timeout_valid = true;
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return 0;
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}
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static int wdt_sifive_feed(const struct device *dev, int channel_id)
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{
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volatile struct wdt_sifive_reg *wdt = DEV_REG(dev);
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wdt->wdogkey = WDOG_KEY;
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wdt->wdogfeed = WDOG_FEED;
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return 0;
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}
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static const struct wdt_driver_api wdt_sifive_api = {
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.setup = wdt_sifive_setup,
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.disable = wdt_sifive_disable,
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.install_timeout = wdt_sifive_install_timeout,
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.feed = wdt_sifive_feed,
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};
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DEVICE_DT_INST_DECLARE(0);
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static void wdt_sifive_irq_config(void)
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{
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IRQ_CONNECT(DT_INST_IRQN(0),
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DT_INST_IRQ(0, priority), wdt_sifive_isr,
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DEVICE_DT_INST_GET(0), 0);
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irq_enable(DT_INST_IRQN(0));
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}
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static int wdt_sifive_init(const struct device *dev)
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{
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#ifdef CONFIG_WDT_DISABLE_AT_BOOT
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wdt_sifive_disable(dev);
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#endif
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wdt_sifive_irq_config();
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return 0;
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}
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static struct wdt_sifive_dev_data wdt_sifive_data;
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static const struct wdt_sifive_device_config wdt_sifive_cfg = {
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.regs = DT_INST_REG_ADDR(0),
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};
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DEVICE_DT_INST_DEFINE(0, wdt_sifive_init, device_pm_control_nop,
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&wdt_sifive_data, &wdt_sifive_cfg, PRE_KERNEL_1,
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CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &wdt_sifive_api);

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