diff options
author | Jiri Kosina <jkosina@suse.cz> | 2023-11-01 02:07:35 +0300 |
---|---|---|
committer | Jiri Kosina <jkosina@suse.cz> | 2023-11-01 02:07:35 +0300 |
commit | 20cd569d7ee8fce24e8753f0f43af6c420557b1f (patch) | |
tree | f559cfda594846795aa51c99d96f92d8c912851a /drivers/watchdog/marvell_gti_wdt.c | |
parent | 62cc9c3cb3ec1bf31cc116146185ed97b450836a (diff) | |
parent | eeebfe6259ba2d5b0980eb7b0df384eb77e9e4f5 (diff) | |
download | linux-20cd569d7ee8fce24e8753f0f43af6c420557b1f.tar.xz |
Merge branch 'for-6.7/config_pm' into for-linus
- #ifdef CONFIG_PM removal from HID code (Thomas Weißschuh)
Diffstat (limited to 'drivers/watchdog/marvell_gti_wdt.c')
-rw-r--r-- | drivers/watchdog/marvell_gti_wdt.c | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/drivers/watchdog/marvell_gti_wdt.c b/drivers/watchdog/marvell_gti_wdt.c new file mode 100644 index 000000000000..d7eb8286e11e --- /dev/null +++ b/drivers/watchdog/marvell_gti_wdt.c @@ -0,0 +1,340 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Marvell GTI Watchdog driver + * + * Copyright (C) 2023 Marvell. + */ + +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/watchdog.h> + +/* + * Hardware supports following mode of operation: + * 1) Interrupt Only: + * This will generate the interrupt to arm core whenever timeout happens. + * + * 2) Interrupt + del3t (Interrupt to firmware (SCP processor)). + * This will generate interrupt to arm core on 1st timeout happens + * This will generate interrupt to SCP processor on 2nd timeout happens + * + * 3) Interrupt + Interrupt to SCP processor (called delt3t) + reboot. + * This will generate interrupt to arm core on 1st timeout happens + * Will generate interrupt to SCP processor on 2nd timeout happens, + * if interrupt is configured. + * Reboot on 3rd timeout. + * + * Driver will use hardware in mode-3 above so that system can reboot in case + * a hardware hang. Also h/w is configured not to generate SCP interrupt, so + * effectively 2nd timeout is ignored within hardware. + * + * First timeout is effectively watchdog pretimeout. + */ + +/* GTI CWD Watchdog (GTI_CWD_WDOG) Register */ +#define GTI_CWD_WDOG(reg_offset) (0x8 * (reg_offset)) +#define GTI_CWD_WDOG_MODE_INT_DEL3T_RST 0x3 +#define GTI_CWD_WDOG_MODE_MASK GENMASK_ULL(1, 0) +#define GTI_CWD_WDOG_LEN_SHIFT 4 +#define GTI_CWD_WDOG_LEN_MASK GENMASK_ULL(19, 4) +#define GTI_CWD_WDOG_CNT_SHIFT 20 +#define GTI_CWD_WDOG_CNT_MASK GENMASK_ULL(43, 20) + +/* GTI CWD Watchdog Interrupt (GTI_CWD_INT) Register */ +#define GTI_CWD_INT 0x200 +#define GTI_CWD_INT_PENDING_STATUS(bit) BIT_ULL(bit) + +/* GTI CWD Watchdog Interrupt Enable Clear (GTI_CWD_INT_ENA_CLR) Register */ +#define GTI_CWD_INT_ENA_CLR 0x210 +#define GTI_CWD_INT_ENA_CLR_VAL(bit) BIT_ULL(bit) + +/* GTI CWD Watchdog Interrupt Enable Set (GTI_CWD_INT_ENA_SET) Register */ +#define GTI_CWD_INT_ENA_SET 0x218 +#define GTI_CWD_INT_ENA_SET_VAL(bit) BIT_ULL(bit) + +/* GTI CWD Watchdog Poke (GTI_CWD_POKE) Registers */ +#define GTI_CWD_POKE(reg_offset) (0x10000 + 0x8 * (reg_offset)) +#define GTI_CWD_POKE_VAL 1 + +struct gti_match_data { + u32 gti_num_timers; +}; + +static const struct gti_match_data match_data_octeontx2 = { + .gti_num_timers = 54, +}; + +static const struct gti_match_data match_data_cn10k = { + .gti_num_timers = 64, +}; + +struct gti_wdt_priv { + struct watchdog_device wdev; + void __iomem *base; + u32 clock_freq; + struct clk *sclk; + /* wdt_timer_idx used for timer to be used for system watchdog */ + u32 wdt_timer_idx; + const struct gti_match_data *data; +}; + +static irqreturn_t gti_wdt_interrupt(int irq, void *data) +{ + struct watchdog_device *wdev = data; + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + + /* Clear Interrupt Pending Status */ + writeq(GTI_CWD_INT_PENDING_STATUS(priv->wdt_timer_idx), + priv->base + GTI_CWD_INT); + + watchdog_notify_pretimeout(wdev); + + return IRQ_HANDLED; +} + +static int gti_wdt_ping(struct watchdog_device *wdev) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + + writeq(GTI_CWD_POKE_VAL, + priv->base + GTI_CWD_POKE(priv->wdt_timer_idx)); + + return 0; +} + +static int gti_wdt_start(struct watchdog_device *wdev) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + u64 regval; + + if (!wdev->pretimeout) + return -EINVAL; + + set_bit(WDOG_HW_RUNNING, &wdev->status); + + /* Clear any pending interrupt */ + writeq(GTI_CWD_INT_PENDING_STATUS(priv->wdt_timer_idx), + priv->base + GTI_CWD_INT); + + /* Enable Interrupt */ + writeq(GTI_CWD_INT_ENA_SET_VAL(priv->wdt_timer_idx), + priv->base + GTI_CWD_INT_ENA_SET); + + /* Set (Interrupt + SCP interrupt (DEL3T) + core domain reset) Mode */ + regval = readq(priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + regval |= GTI_CWD_WDOG_MODE_INT_DEL3T_RST; + writeq(regval, priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + + return 0; +} + +static int gti_wdt_stop(struct watchdog_device *wdev) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + u64 regval; + + /* Disable Interrupt */ + writeq(GTI_CWD_INT_ENA_CLR_VAL(priv->wdt_timer_idx), + priv->base + GTI_CWD_INT_ENA_CLR); + + /* Set GTI_CWD_WDOG.Mode = 0 to stop the timer */ + regval = readq(priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + regval &= ~GTI_CWD_WDOG_MODE_MASK; + writeq(regval, priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + + return 0; +} + +static int gti_wdt_settimeout(struct watchdog_device *wdev, + unsigned int timeout) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + u64 timeout_wdog, regval; + + /* Update new timeout */ + wdev->timeout = timeout; + + /* Pretimeout is 1/3 of timeout */ + wdev->pretimeout = timeout / 3; + + /* Get clock cycles from pretimeout */ + timeout_wdog = (u64)priv->clock_freq * wdev->pretimeout; + + /* Watchdog counts in 1024 cycle steps */ + timeout_wdog = timeout_wdog >> 10; + + /* GTI_CWD_WDOG.CNT: reload counter is 16-bit */ + timeout_wdog = (timeout_wdog + 0xff) >> 8; + if (timeout_wdog >= 0x10000) + timeout_wdog = 0xffff; + + /* + * GTI_CWD_WDOG.LEN is 24bit, lower 8-bits should be zero and + * upper 16-bits are same as GTI_CWD_WDOG.CNT + */ + regval = readq(priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + regval &= GTI_CWD_WDOG_MODE_MASK; + regval |= (timeout_wdog << (GTI_CWD_WDOG_CNT_SHIFT + 8)) | + (timeout_wdog << GTI_CWD_WDOG_LEN_SHIFT); + writeq(regval, priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + + return 0; +} + +static int gti_wdt_set_pretimeout(struct watchdog_device *wdev, + unsigned int timeout) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + struct watchdog_device *wdog_dev = &priv->wdev; + + /* pretimeout should 1/3 of max_timeout */ + if (timeout * 3 <= wdog_dev->max_timeout) + return gti_wdt_settimeout(wdev, timeout * 3); + + return -EINVAL; +} + +static void gti_clk_disable_unprepare(void *data) +{ + clk_disable_unprepare(data); +} + +static int gti_wdt_get_cntfrq(struct platform_device *pdev, + struct gti_wdt_priv *priv) +{ + int err; + + priv->sclk = devm_clk_get_enabled(&pdev->dev, NULL); + if (IS_ERR(priv->sclk)) + return PTR_ERR(priv->sclk); + + err = devm_add_action_or_reset(&pdev->dev, + gti_clk_disable_unprepare, priv->sclk); + if (err) + return err; + + priv->clock_freq = clk_get_rate(priv->sclk); + if (!priv->clock_freq) + return -EINVAL; + + return 0; +} + +static const struct watchdog_info gti_wdt_ident = { + .identity = "Marvell GTI watchdog", + .options = WDIOF_SETTIMEOUT | WDIOF_PRETIMEOUT | WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE | WDIOF_CARDRESET, +}; + +static const struct watchdog_ops gti_wdt_ops = { + .owner = THIS_MODULE, + .start = gti_wdt_start, + .stop = gti_wdt_stop, + .ping = gti_wdt_ping, + .set_timeout = gti_wdt_settimeout, + .set_pretimeout = gti_wdt_set_pretimeout, +}; + +static int gti_wdt_probe(struct platform_device *pdev) +{ + struct gti_wdt_priv *priv; + struct device *dev = &pdev->dev; + struct watchdog_device *wdog_dev; + u64 max_pretimeout; + u32 wdt_idx; + int irq; + int err; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->base)) + return dev_err_probe(&pdev->dev, PTR_ERR(priv->base), + "reg property not valid/found\n"); + + err = gti_wdt_get_cntfrq(pdev, priv); + if (err) + return dev_err_probe(&pdev->dev, err, + "GTI clock frequency not valid/found"); + + priv->data = of_device_get_match_data(dev); + + /* default use last timer for watchdog */ + priv->wdt_timer_idx = priv->data->gti_num_timers - 1; + + err = of_property_read_u32(dev->of_node, "marvell,wdt-timer-index", + &wdt_idx); + if (!err) { + if (wdt_idx >= priv->data->gti_num_timers) + return dev_err_probe(&pdev->dev, err, + "GTI wdog timer index not valid"); + + priv->wdt_timer_idx = wdt_idx; + } + + wdog_dev = &priv->wdev; + wdog_dev->info = >i_wdt_ident, + wdog_dev->ops = >i_wdt_ops, + wdog_dev->parent = dev; + /* + * Watchdog counter is 24 bit where lower 8 bits are zeros + * This counter decrements every 1024 clock cycles. + */ + max_pretimeout = (GTI_CWD_WDOG_CNT_MASK >> GTI_CWD_WDOG_CNT_SHIFT); + max_pretimeout &= ~0xFFUL; + max_pretimeout = (max_pretimeout * 1024) / priv->clock_freq; + wdog_dev->pretimeout = max_pretimeout; + + /* Maximum timeout is 3 times the pretimeout */ + wdog_dev->max_timeout = max_pretimeout * 3; + /* Minimum first timeout (pretimeout) is 1, so min_timeout as 3 */ + wdog_dev->min_timeout = 3; + wdog_dev->timeout = wdog_dev->pretimeout; + + watchdog_set_drvdata(wdog_dev, priv); + platform_set_drvdata(pdev, priv); + gti_wdt_settimeout(wdog_dev, wdog_dev->timeout); + watchdog_stop_on_reboot(wdog_dev); + watchdog_stop_on_unregister(wdog_dev); + + err = devm_watchdog_register_device(dev, wdog_dev); + if (err) + return err; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return dev_err_probe(&pdev->dev, irq, "IRQ resource not found\n"); + + err = devm_request_irq(dev, irq, gti_wdt_interrupt, 0, + pdev->name, &priv->wdev); + if (err) + return dev_err_probe(dev, err, "Failed to register interrupt handler\n"); + + dev_info(dev, "Watchdog enabled (timeout=%d sec)\n", wdog_dev->timeout); + return 0; +} + +static const struct of_device_id gti_wdt_of_match[] = { + { .compatible = "marvell,cn9670-wdt", .data = &match_data_octeontx2}, + { .compatible = "marvell,cn10624-wdt", .data = &match_data_cn10k}, + { }, +}; +MODULE_DEVICE_TABLE(of, gti_wdt_of_match); + +static struct platform_driver gti_wdt_driver = { + .driver = { + .name = "gti-wdt", + .of_match_table = gti_wdt_of_match, + }, + .probe = gti_wdt_probe, +}; +module_platform_driver(gti_wdt_driver); + +MODULE_AUTHOR("Bharat Bhushan <bbhushan2@marvell.com>"); +MODULE_DESCRIPTION("Marvell GTI watchdog driver"); +MODULE_LICENSE("GPL"); |