^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright (C) 2015 Broadcom Corporation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/clk.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/of.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/pm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/watchdog.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #define WDT_START_1 0xff00
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #define WDT_START_2 0x00ff
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #define WDT_STOP_1 0xee00
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #define WDT_STOP_2 0x00ee
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #define WDT_TIMEOUT_REG 0x0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #define WDT_CMD_REG 0x4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #define WDT_MIN_TIMEOUT 1 /* seconds */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #define WDT_DEFAULT_TIMEOUT 30 /* seconds */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #define WDT_DEFAULT_RATE 27000000
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) struct bcm7038_watchdog {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) void __iomem *base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) struct watchdog_device wdd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) u32 rate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) struct clk *clk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) static bool nowayout = WATCHDOG_NOWAYOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) static void bcm7038_wdt_set_timeout_reg(struct watchdog_device *wdog)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) struct bcm7038_watchdog *wdt = watchdog_get_drvdata(wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) u32 timeout;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) timeout = wdt->rate * wdog->timeout;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) writel(timeout, wdt->base + WDT_TIMEOUT_REG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) static int bcm7038_wdt_ping(struct watchdog_device *wdog)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) struct bcm7038_watchdog *wdt = watchdog_get_drvdata(wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) writel(WDT_START_1, wdt->base + WDT_CMD_REG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) writel(WDT_START_2, wdt->base + WDT_CMD_REG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) static int bcm7038_wdt_start(struct watchdog_device *wdog)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) bcm7038_wdt_set_timeout_reg(wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) bcm7038_wdt_ping(wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) static int bcm7038_wdt_stop(struct watchdog_device *wdog)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) struct bcm7038_watchdog *wdt = watchdog_get_drvdata(wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) writel(WDT_STOP_1, wdt->base + WDT_CMD_REG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) writel(WDT_STOP_2, wdt->base + WDT_CMD_REG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) static int bcm7038_wdt_set_timeout(struct watchdog_device *wdog,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) unsigned int t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) /* Can't modify timeout value if watchdog timer is running */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) bcm7038_wdt_stop(wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) wdog->timeout = t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) bcm7038_wdt_start(wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) static unsigned int bcm7038_wdt_get_timeleft(struct watchdog_device *wdog)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) struct bcm7038_watchdog *wdt = watchdog_get_drvdata(wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) u32 time_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) time_left = readl(wdt->base + WDT_CMD_REG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) return time_left / wdt->rate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) static const struct watchdog_info bcm7038_wdt_info = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) .identity = "Broadcom BCM7038 Watchdog Timer",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) WDIOF_MAGICCLOSE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) static const struct watchdog_ops bcm7038_wdt_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) .owner = THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) .start = bcm7038_wdt_start,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) .stop = bcm7038_wdt_stop,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) .set_timeout = bcm7038_wdt_set_timeout,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) .get_timeleft = bcm7038_wdt_get_timeleft,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) static void bcm7038_clk_disable_unprepare(void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) clk_disable_unprepare(data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) static int bcm7038_wdt_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) struct device *dev = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) struct bcm7038_watchdog *wdt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) if (!wdt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) platform_set_drvdata(pdev, wdt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) wdt->base = devm_platform_ioremap_resource(pdev, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) if (IS_ERR(wdt->base))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) return PTR_ERR(wdt->base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) wdt->clk = devm_clk_get(dev, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) /* If unable to get clock, use default frequency */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) if (!IS_ERR(wdt->clk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) err = clk_prepare_enable(wdt->clk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) err = devm_add_action_or_reset(dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) bcm7038_clk_disable_unprepare,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) wdt->clk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) wdt->rate = clk_get_rate(wdt->clk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) /* Prevent divide-by-zero exception */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) if (!wdt->rate)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) wdt->rate = WDT_DEFAULT_RATE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) wdt->rate = WDT_DEFAULT_RATE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) wdt->clk = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) wdt->wdd.info = &bcm7038_wdt_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) wdt->wdd.ops = &bcm7038_wdt_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) wdt->wdd.min_timeout = WDT_MIN_TIMEOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) wdt->wdd.timeout = WDT_DEFAULT_TIMEOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) wdt->wdd.max_timeout = 0xffffffff / wdt->rate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) wdt->wdd.parent = dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) watchdog_set_drvdata(&wdt->wdd, wdt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) watchdog_stop_on_reboot(&wdt->wdd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) watchdog_stop_on_unregister(&wdt->wdd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) err = devm_watchdog_register_device(dev, &wdt->wdd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) dev_info(dev, "Registered BCM7038 Watchdog\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) #ifdef CONFIG_PM_SLEEP
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) static int bcm7038_wdt_suspend(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) struct bcm7038_watchdog *wdt = dev_get_drvdata(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) if (watchdog_active(&wdt->wdd))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) return bcm7038_wdt_stop(&wdt->wdd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) static int bcm7038_wdt_resume(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) struct bcm7038_watchdog *wdt = dev_get_drvdata(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) if (watchdog_active(&wdt->wdd))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) return bcm7038_wdt_start(&wdt->wdd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) static SIMPLE_DEV_PM_OPS(bcm7038_wdt_pm_ops, bcm7038_wdt_suspend,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) bcm7038_wdt_resume);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) static const struct of_device_id bcm7038_wdt_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) { .compatible = "brcm,bcm7038-wdt" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) {},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) MODULE_DEVICE_TABLE(of, bcm7038_wdt_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) static struct platform_driver bcm7038_wdt_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) .probe = bcm7038_wdt_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) .name = "bcm7038-wdt",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) .of_match_table = bcm7038_wdt_match,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) .pm = &bcm7038_wdt_pm_ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) module_platform_driver(bcm7038_wdt_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) module_param(nowayout, bool, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) MODULE_DESCRIPTION("Driver for Broadcom 7038 SoCs Watchdog");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) MODULE_AUTHOR("Justin Chen");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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