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![Alexander A. Klimov](/assets/img/avatar_default.png)
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20200713205821.38223-1-grandmaster@al2klimov.de Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
722 lines
19 KiB
C
722 lines
19 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Copyright 2010-2011 Picochip Ltd., Jamie Iles
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* https://www.picochip.com
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*
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* This file implements a driver for the Synopsys DesignWare watchdog device
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* in the many subsystems. The watchdog has 16 different timeout periods
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* and these are a function of the input clock frequency.
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*
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* The DesignWare watchdog cannot be stopped once it has been started so we
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* do not implement a stop function. The watchdog core will continue to send
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* heartbeat requests after the watchdog device has been closed.
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*/
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#include <linux/bitops.h>
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#include <linux/limits.h>
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#include <linux/kernel.h>
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/err.h>
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#include <linux/io.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/interrupt.h>
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#include <linux/of.h>
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#include <linux/pm.h>
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#include <linux/platform_device.h>
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#include <linux/reset.h>
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#include <linux/watchdog.h>
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#include <linux/debugfs.h>
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#define WDOG_CONTROL_REG_OFFSET 0x00
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#define WDOG_CONTROL_REG_WDT_EN_MASK 0x01
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#define WDOG_CONTROL_REG_RESP_MODE_MASK 0x02
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#define WDOG_TIMEOUT_RANGE_REG_OFFSET 0x04
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#define WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT 4
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#define WDOG_CURRENT_COUNT_REG_OFFSET 0x08
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#define WDOG_COUNTER_RESTART_REG_OFFSET 0x0c
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#define WDOG_COUNTER_RESTART_KICK_VALUE 0x76
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#define WDOG_INTERRUPT_STATUS_REG_OFFSET 0x10
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#define WDOG_INTERRUPT_CLEAR_REG_OFFSET 0x14
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#define WDOG_COMP_PARAMS_5_REG_OFFSET 0xe4
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#define WDOG_COMP_PARAMS_4_REG_OFFSET 0xe8
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#define WDOG_COMP_PARAMS_3_REG_OFFSET 0xec
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#define WDOG_COMP_PARAMS_2_REG_OFFSET 0xf0
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#define WDOG_COMP_PARAMS_1_REG_OFFSET 0xf4
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#define WDOG_COMP_PARAMS_1_USE_FIX_TOP BIT(6)
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#define WDOG_COMP_VERSION_REG_OFFSET 0xf8
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#define WDOG_COMP_TYPE_REG_OFFSET 0xfc
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/* There are sixteen TOPs (timeout periods) that can be set in the watchdog. */
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#define DW_WDT_NUM_TOPS 16
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#define DW_WDT_FIX_TOP(_idx) (1U << (16 + _idx))
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#define DW_WDT_DEFAULT_SECONDS 30
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static const u32 dw_wdt_fix_tops[DW_WDT_NUM_TOPS] = {
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DW_WDT_FIX_TOP(0), DW_WDT_FIX_TOP(1), DW_WDT_FIX_TOP(2),
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DW_WDT_FIX_TOP(3), DW_WDT_FIX_TOP(4), DW_WDT_FIX_TOP(5),
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DW_WDT_FIX_TOP(6), DW_WDT_FIX_TOP(7), DW_WDT_FIX_TOP(8),
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DW_WDT_FIX_TOP(9), DW_WDT_FIX_TOP(10), DW_WDT_FIX_TOP(11),
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DW_WDT_FIX_TOP(12), DW_WDT_FIX_TOP(13), DW_WDT_FIX_TOP(14),
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DW_WDT_FIX_TOP(15)
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};
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static bool nowayout = WATCHDOG_NOWAYOUT;
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module_param(nowayout, bool, 0);
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MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
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"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
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enum dw_wdt_rmod {
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DW_WDT_RMOD_RESET = 1,
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DW_WDT_RMOD_IRQ = 2
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};
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struct dw_wdt_timeout {
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u32 top_val;
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unsigned int sec;
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unsigned int msec;
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};
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struct dw_wdt {
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void __iomem *regs;
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struct clk *clk;
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struct clk *pclk;
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unsigned long rate;
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enum dw_wdt_rmod rmod;
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struct dw_wdt_timeout timeouts[DW_WDT_NUM_TOPS];
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struct watchdog_device wdd;
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struct reset_control *rst;
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/* Save/restore */
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u32 control;
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u32 timeout;
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#ifdef CONFIG_DEBUG_FS
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struct dentry *dbgfs_dir;
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#endif
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};
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#define to_dw_wdt(wdd) container_of(wdd, struct dw_wdt, wdd)
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static inline int dw_wdt_is_enabled(struct dw_wdt *dw_wdt)
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{
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return readl(dw_wdt->regs + WDOG_CONTROL_REG_OFFSET) &
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WDOG_CONTROL_REG_WDT_EN_MASK;
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}
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static void dw_wdt_update_mode(struct dw_wdt *dw_wdt, enum dw_wdt_rmod rmod)
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{
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u32 val;
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val = readl(dw_wdt->regs + WDOG_CONTROL_REG_OFFSET);
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if (rmod == DW_WDT_RMOD_IRQ)
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val |= WDOG_CONTROL_REG_RESP_MODE_MASK;
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else
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val &= ~WDOG_CONTROL_REG_RESP_MODE_MASK;
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writel(val, dw_wdt->regs + WDOG_CONTROL_REG_OFFSET);
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dw_wdt->rmod = rmod;
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}
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static unsigned int dw_wdt_find_best_top(struct dw_wdt *dw_wdt,
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unsigned int timeout, u32 *top_val)
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{
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int idx;
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/*
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* Find a TOP with timeout greater or equal to the requested number.
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* Note we'll select a TOP with maximum timeout if the requested
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* timeout couldn't be reached.
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*/
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for (idx = 0; idx < DW_WDT_NUM_TOPS; ++idx) {
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if (dw_wdt->timeouts[idx].sec >= timeout)
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break;
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}
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if (idx == DW_WDT_NUM_TOPS)
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--idx;
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*top_val = dw_wdt->timeouts[idx].top_val;
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return dw_wdt->timeouts[idx].sec;
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}
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static unsigned int dw_wdt_get_min_timeout(struct dw_wdt *dw_wdt)
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{
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int idx;
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/*
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* We'll find a timeout greater or equal to one second anyway because
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* the driver probe would have failed if there was none.
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*/
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for (idx = 0; idx < DW_WDT_NUM_TOPS; ++idx) {
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if (dw_wdt->timeouts[idx].sec)
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break;
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}
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return dw_wdt->timeouts[idx].sec;
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}
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static unsigned int dw_wdt_get_max_timeout_ms(struct dw_wdt *dw_wdt)
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{
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struct dw_wdt_timeout *timeout = &dw_wdt->timeouts[DW_WDT_NUM_TOPS - 1];
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u64 msec;
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msec = (u64)timeout->sec * MSEC_PER_SEC + timeout->msec;
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return msec < UINT_MAX ? msec : UINT_MAX;
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}
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static unsigned int dw_wdt_get_timeout(struct dw_wdt *dw_wdt)
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{
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int top_val = readl(dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET) & 0xF;
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int idx;
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for (idx = 0; idx < DW_WDT_NUM_TOPS; ++idx) {
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if (dw_wdt->timeouts[idx].top_val == top_val)
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break;
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}
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/*
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* In IRQ mode due to the two stages counter, the actual timeout is
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* twice greater than the TOP setting.
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*/
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return dw_wdt->timeouts[idx].sec * dw_wdt->rmod;
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}
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static int dw_wdt_ping(struct watchdog_device *wdd)
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{
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struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
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writel(WDOG_COUNTER_RESTART_KICK_VALUE, dw_wdt->regs +
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WDOG_COUNTER_RESTART_REG_OFFSET);
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return 0;
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}
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static int dw_wdt_set_timeout(struct watchdog_device *wdd, unsigned int top_s)
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{
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struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
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unsigned int timeout;
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u32 top_val;
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/*
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* Note IRQ mode being enabled means having a non-zero pre-timeout
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* setup. In this case we try to find a TOP as close to the half of the
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* requested timeout as possible since DW Watchdog IRQ mode is designed
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* in two stages way - first timeout rises the pre-timeout interrupt,
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* second timeout performs the system reset. So basically the effective
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* watchdog-caused reset happens after two watchdog TOPs elapsed.
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*/
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timeout = dw_wdt_find_best_top(dw_wdt, DIV_ROUND_UP(top_s, dw_wdt->rmod),
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&top_val);
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if (dw_wdt->rmod == DW_WDT_RMOD_IRQ)
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wdd->pretimeout = timeout;
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else
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wdd->pretimeout = 0;
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/*
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* Set the new value in the watchdog. Some versions of dw_wdt
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* have have TOPINIT in the TIMEOUT_RANGE register (as per
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* CP_WDT_DUAL_TOP in WDT_COMP_PARAMS_1). On those we
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* effectively get a pat of the watchdog right here.
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*/
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writel(top_val | top_val << WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT,
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dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);
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/* Kick new TOP value into the watchdog counter if activated. */
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if (watchdog_active(wdd))
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dw_wdt_ping(wdd);
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/*
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* In case users set bigger timeout value than HW can support,
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* kernel(watchdog_dev.c) helps to feed watchdog before
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* wdd->max_hw_heartbeat_ms
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*/
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if (top_s * 1000 <= wdd->max_hw_heartbeat_ms)
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wdd->timeout = timeout * dw_wdt->rmod;
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else
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wdd->timeout = top_s;
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return 0;
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}
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static int dw_wdt_set_pretimeout(struct watchdog_device *wdd, unsigned int req)
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{
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struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
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/*
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* We ignore actual value of the timeout passed from user-space
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* using it as a flag whether the pretimeout functionality is intended
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* to be activated.
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*/
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dw_wdt_update_mode(dw_wdt, req ? DW_WDT_RMOD_IRQ : DW_WDT_RMOD_RESET);
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dw_wdt_set_timeout(wdd, wdd->timeout);
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return 0;
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}
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static void dw_wdt_arm_system_reset(struct dw_wdt *dw_wdt)
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{
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u32 val = readl(dw_wdt->regs + WDOG_CONTROL_REG_OFFSET);
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/* Disable/enable interrupt mode depending on the RMOD flag. */
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if (dw_wdt->rmod == DW_WDT_RMOD_IRQ)
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val |= WDOG_CONTROL_REG_RESP_MODE_MASK;
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else
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val &= ~WDOG_CONTROL_REG_RESP_MODE_MASK;
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/* Enable watchdog. */
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val |= WDOG_CONTROL_REG_WDT_EN_MASK;
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writel(val, dw_wdt->regs + WDOG_CONTROL_REG_OFFSET);
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}
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static int dw_wdt_start(struct watchdog_device *wdd)
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{
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struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
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dw_wdt_set_timeout(wdd, wdd->timeout);
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dw_wdt_ping(&dw_wdt->wdd);
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dw_wdt_arm_system_reset(dw_wdt);
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return 0;
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}
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static int dw_wdt_stop(struct watchdog_device *wdd)
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{
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struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
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if (!dw_wdt->rst) {
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set_bit(WDOG_HW_RUNNING, &wdd->status);
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return 0;
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}
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reset_control_assert(dw_wdt->rst);
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reset_control_deassert(dw_wdt->rst);
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return 0;
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}
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static int dw_wdt_restart(struct watchdog_device *wdd,
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unsigned long action, void *data)
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{
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struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
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writel(0, dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);
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dw_wdt_update_mode(dw_wdt, DW_WDT_RMOD_RESET);
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if (dw_wdt_is_enabled(dw_wdt))
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writel(WDOG_COUNTER_RESTART_KICK_VALUE,
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dw_wdt->regs + WDOG_COUNTER_RESTART_REG_OFFSET);
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else
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dw_wdt_arm_system_reset(dw_wdt);
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/* wait for reset to assert... */
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mdelay(500);
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return 0;
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}
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static unsigned int dw_wdt_get_timeleft(struct watchdog_device *wdd)
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{
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struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
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unsigned int sec;
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u32 val;
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val = readl(dw_wdt->regs + WDOG_CURRENT_COUNT_REG_OFFSET);
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sec = val / dw_wdt->rate;
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if (dw_wdt->rmod == DW_WDT_RMOD_IRQ) {
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val = readl(dw_wdt->regs + WDOG_INTERRUPT_STATUS_REG_OFFSET);
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if (!val)
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sec += wdd->pretimeout;
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}
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return sec;
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}
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static const struct watchdog_info dw_wdt_ident = {
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.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
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WDIOF_MAGICCLOSE,
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.identity = "Synopsys DesignWare Watchdog",
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};
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static const struct watchdog_info dw_wdt_pt_ident = {
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.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
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WDIOF_PRETIMEOUT | WDIOF_MAGICCLOSE,
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.identity = "Synopsys DesignWare Watchdog",
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};
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static const struct watchdog_ops dw_wdt_ops = {
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.owner = THIS_MODULE,
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.start = dw_wdt_start,
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.stop = dw_wdt_stop,
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.ping = dw_wdt_ping,
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.set_timeout = dw_wdt_set_timeout,
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.set_pretimeout = dw_wdt_set_pretimeout,
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.get_timeleft = dw_wdt_get_timeleft,
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.restart = dw_wdt_restart,
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};
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static irqreturn_t dw_wdt_irq(int irq, void *devid)
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{
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struct dw_wdt *dw_wdt = devid;
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u32 val;
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/*
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* We don't clear the IRQ status. It's supposed to be done by the
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* following ping operations.
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*/
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val = readl(dw_wdt->regs + WDOG_INTERRUPT_STATUS_REG_OFFSET);
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if (!val)
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return IRQ_NONE;
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watchdog_notify_pretimeout(&dw_wdt->wdd);
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return IRQ_HANDLED;
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}
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#ifdef CONFIG_PM_SLEEP
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static int dw_wdt_suspend(struct device *dev)
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{
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struct dw_wdt *dw_wdt = dev_get_drvdata(dev);
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dw_wdt->control = readl(dw_wdt->regs + WDOG_CONTROL_REG_OFFSET);
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dw_wdt->timeout = readl(dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);
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clk_disable_unprepare(dw_wdt->pclk);
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clk_disable_unprepare(dw_wdt->clk);
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return 0;
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}
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static int dw_wdt_resume(struct device *dev)
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{
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struct dw_wdt *dw_wdt = dev_get_drvdata(dev);
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int err = clk_prepare_enable(dw_wdt->clk);
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if (err)
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return err;
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err = clk_prepare_enable(dw_wdt->pclk);
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if (err) {
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clk_disable_unprepare(dw_wdt->clk);
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return err;
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}
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writel(dw_wdt->timeout, dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);
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writel(dw_wdt->control, dw_wdt->regs + WDOG_CONTROL_REG_OFFSET);
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dw_wdt_ping(&dw_wdt->wdd);
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return 0;
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}
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#endif /* CONFIG_PM_SLEEP */
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static SIMPLE_DEV_PM_OPS(dw_wdt_pm_ops, dw_wdt_suspend, dw_wdt_resume);
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/*
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* In case if DW WDT IP core is synthesized with fixed TOP feature disabled the
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* TOPs array can be arbitrary ordered with nearly any sixteen uint numbers
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* depending on the system engineer imagination. The next method handles the
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* passed TOPs array to pre-calculate the effective timeouts and to sort the
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* TOP items out in the ascending order with respect to the timeouts.
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*/
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static void dw_wdt_handle_tops(struct dw_wdt *dw_wdt, const u32 *tops)
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{
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struct dw_wdt_timeout tout, *dst;
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int val, tidx;
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u64 msec;
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/*
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* We walk over the passed TOPs array and calculate corresponding
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* timeouts in seconds and milliseconds. The milliseconds granularity
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* is needed to distinguish the TOPs with very close timeouts and to
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* set the watchdog max heartbeat setting further.
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*/
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for (val = 0; val < DW_WDT_NUM_TOPS; ++val) {
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tout.top_val = val;
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tout.sec = tops[val] / dw_wdt->rate;
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msec = (u64)tops[val] * MSEC_PER_SEC;
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do_div(msec, dw_wdt->rate);
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tout.msec = msec - ((u64)tout.sec * MSEC_PER_SEC);
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/*
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* Find a suitable place for the current TOP in the timeouts
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* array so that the list is remained in the ascending order.
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*/
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for (tidx = 0; tidx < val; ++tidx) {
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dst = &dw_wdt->timeouts[tidx];
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if (tout.sec > dst->sec || (tout.sec == dst->sec &&
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tout.msec >= dst->msec))
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continue;
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else
|
|
swap(*dst, tout);
|
|
}
|
|
|
|
dw_wdt->timeouts[val] = tout;
|
|
}
|
|
}
|
|
|
|
static int dw_wdt_init_timeouts(struct dw_wdt *dw_wdt, struct device *dev)
|
|
{
|
|
u32 data, of_tops[DW_WDT_NUM_TOPS];
|
|
const u32 *tops;
|
|
int ret;
|
|
|
|
/*
|
|
* Retrieve custom or fixed counter values depending on the
|
|
* WDT_USE_FIX_TOP flag found in the component specific parameters
|
|
* #1 register.
|
|
*/
|
|
data = readl(dw_wdt->regs + WDOG_COMP_PARAMS_1_REG_OFFSET);
|
|
if (data & WDOG_COMP_PARAMS_1_USE_FIX_TOP) {
|
|
tops = dw_wdt_fix_tops;
|
|
} else {
|
|
ret = of_property_read_variable_u32_array(dev_of_node(dev),
|
|
"snps,watchdog-tops", of_tops, DW_WDT_NUM_TOPS,
|
|
DW_WDT_NUM_TOPS);
|
|
if (ret < 0) {
|
|
dev_warn(dev, "No valid TOPs array specified\n");
|
|
tops = dw_wdt_fix_tops;
|
|
} else {
|
|
tops = of_tops;
|
|
}
|
|
}
|
|
|
|
/* Convert the specified TOPs into an array of watchdog timeouts. */
|
|
dw_wdt_handle_tops(dw_wdt, tops);
|
|
if (!dw_wdt->timeouts[DW_WDT_NUM_TOPS - 1].sec) {
|
|
dev_err(dev, "No any valid TOP detected\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_FS
|
|
|
|
#define DW_WDT_DBGFS_REG(_name, _off) \
|
|
{ \
|
|
.name = _name, \
|
|
.offset = _off \
|
|
}
|
|
|
|
static const struct debugfs_reg32 dw_wdt_dbgfs_regs[] = {
|
|
DW_WDT_DBGFS_REG("cr", WDOG_CONTROL_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("torr", WDOG_TIMEOUT_RANGE_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("ccvr", WDOG_CURRENT_COUNT_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("crr", WDOG_COUNTER_RESTART_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("stat", WDOG_INTERRUPT_STATUS_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("param5", WDOG_COMP_PARAMS_5_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("param4", WDOG_COMP_PARAMS_4_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("param3", WDOG_COMP_PARAMS_3_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("param2", WDOG_COMP_PARAMS_2_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("param1", WDOG_COMP_PARAMS_1_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("version", WDOG_COMP_VERSION_REG_OFFSET),
|
|
DW_WDT_DBGFS_REG("type", WDOG_COMP_TYPE_REG_OFFSET)
|
|
};
|
|
|
|
static void dw_wdt_dbgfs_init(struct dw_wdt *dw_wdt)
|
|
{
|
|
struct device *dev = dw_wdt->wdd.parent;
|
|
struct debugfs_regset32 *regset;
|
|
|
|
regset = devm_kzalloc(dev, sizeof(*regset), GFP_KERNEL);
|
|
if (!regset)
|
|
return;
|
|
|
|
regset->regs = dw_wdt_dbgfs_regs;
|
|
regset->nregs = ARRAY_SIZE(dw_wdt_dbgfs_regs);
|
|
regset->base = dw_wdt->regs;
|
|
|
|
dw_wdt->dbgfs_dir = debugfs_create_dir(dev_name(dev), NULL);
|
|
|
|
debugfs_create_regset32("registers", 0444, dw_wdt->dbgfs_dir, regset);
|
|
}
|
|
|
|
static void dw_wdt_dbgfs_clear(struct dw_wdt *dw_wdt)
|
|
{
|
|
debugfs_remove_recursive(dw_wdt->dbgfs_dir);
|
|
}
|
|
|
|
#else /* !CONFIG_DEBUG_FS */
|
|
|
|
static void dw_wdt_dbgfs_init(struct dw_wdt *dw_wdt) {}
|
|
static void dw_wdt_dbgfs_clear(struct dw_wdt *dw_wdt) {}
|
|
|
|
#endif /* !CONFIG_DEBUG_FS */
|
|
|
|
static int dw_wdt_drv_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct watchdog_device *wdd;
|
|
struct dw_wdt *dw_wdt;
|
|
int ret;
|
|
|
|
dw_wdt = devm_kzalloc(dev, sizeof(*dw_wdt), GFP_KERNEL);
|
|
if (!dw_wdt)
|
|
return -ENOMEM;
|
|
|
|
dw_wdt->regs = devm_platform_ioremap_resource(pdev, 0);
|
|
if (IS_ERR(dw_wdt->regs))
|
|
return PTR_ERR(dw_wdt->regs);
|
|
|
|
/*
|
|
* Try to request the watchdog dedicated timer clock source. It must
|
|
* be supplied if asynchronous mode is enabled. Otherwise fallback
|
|
* to the common timer/bus clocks configuration, in which the very
|
|
* first found clock supply both timer and APB signals.
|
|
*/
|
|
dw_wdt->clk = devm_clk_get(dev, "tclk");
|
|
if (IS_ERR(dw_wdt->clk)) {
|
|
dw_wdt->clk = devm_clk_get(dev, NULL);
|
|
if (IS_ERR(dw_wdt->clk))
|
|
return PTR_ERR(dw_wdt->clk);
|
|
}
|
|
|
|
ret = clk_prepare_enable(dw_wdt->clk);
|
|
if (ret)
|
|
return ret;
|
|
|
|
dw_wdt->rate = clk_get_rate(dw_wdt->clk);
|
|
if (dw_wdt->rate == 0) {
|
|
ret = -EINVAL;
|
|
goto out_disable_clk;
|
|
}
|
|
|
|
/*
|
|
* Request APB clock if device is configured with async clocks mode.
|
|
* In this case both tclk and pclk clocks are supposed to be specified.
|
|
* Alas we can't know for sure whether async mode was really activated,
|
|
* so the pclk phandle reference is left optional. If it couldn't be
|
|
* found we consider the device configured in synchronous clocks mode.
|
|
*/
|
|
dw_wdt->pclk = devm_clk_get_optional(dev, "pclk");
|
|
if (IS_ERR(dw_wdt->pclk)) {
|
|
ret = PTR_ERR(dw_wdt->pclk);
|
|
goto out_disable_clk;
|
|
}
|
|
|
|
ret = clk_prepare_enable(dw_wdt->pclk);
|
|
if (ret)
|
|
goto out_disable_clk;
|
|
|
|
dw_wdt->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL);
|
|
if (IS_ERR(dw_wdt->rst)) {
|
|
ret = PTR_ERR(dw_wdt->rst);
|
|
goto out_disable_pclk;
|
|
}
|
|
|
|
/* Enable normal reset without pre-timeout by default. */
|
|
dw_wdt_update_mode(dw_wdt, DW_WDT_RMOD_RESET);
|
|
|
|
/*
|
|
* Pre-timeout IRQ is optional, since some hardware may lack support
|
|
* of it. Note we must request rising-edge IRQ, since the lane is left
|
|
* pending either until the next watchdog kick event or up to the
|
|
* system reset.
|
|
*/
|
|
ret = platform_get_irq_optional(pdev, 0);
|
|
if (ret > 0) {
|
|
ret = devm_request_irq(dev, ret, dw_wdt_irq,
|
|
IRQF_SHARED | IRQF_TRIGGER_RISING,
|
|
pdev->name, dw_wdt);
|
|
if (ret)
|
|
goto out_disable_pclk;
|
|
|
|
dw_wdt->wdd.info = &dw_wdt_pt_ident;
|
|
} else {
|
|
if (ret == -EPROBE_DEFER)
|
|
goto out_disable_pclk;
|
|
|
|
dw_wdt->wdd.info = &dw_wdt_ident;
|
|
}
|
|
|
|
reset_control_deassert(dw_wdt->rst);
|
|
|
|
ret = dw_wdt_init_timeouts(dw_wdt, dev);
|
|
if (ret)
|
|
goto out_disable_clk;
|
|
|
|
wdd = &dw_wdt->wdd;
|
|
wdd->ops = &dw_wdt_ops;
|
|
wdd->min_timeout = dw_wdt_get_min_timeout(dw_wdt);
|
|
wdd->max_hw_heartbeat_ms = dw_wdt_get_max_timeout_ms(dw_wdt);
|
|
wdd->parent = dev;
|
|
|
|
watchdog_set_drvdata(wdd, dw_wdt);
|
|
watchdog_set_nowayout(wdd, nowayout);
|
|
watchdog_init_timeout(wdd, 0, dev);
|
|
|
|
/*
|
|
* If the watchdog is already running, use its already configured
|
|
* timeout. Otherwise use the default or the value provided through
|
|
* devicetree.
|
|
*/
|
|
if (dw_wdt_is_enabled(dw_wdt)) {
|
|
wdd->timeout = dw_wdt_get_timeout(dw_wdt);
|
|
set_bit(WDOG_HW_RUNNING, &wdd->status);
|
|
} else {
|
|
wdd->timeout = DW_WDT_DEFAULT_SECONDS;
|
|
watchdog_init_timeout(wdd, 0, dev);
|
|
}
|
|
|
|
platform_set_drvdata(pdev, dw_wdt);
|
|
|
|
watchdog_set_restart_priority(wdd, 128);
|
|
|
|
ret = watchdog_register_device(wdd);
|
|
if (ret)
|
|
goto out_disable_pclk;
|
|
|
|
dw_wdt_dbgfs_init(dw_wdt);
|
|
|
|
return 0;
|
|
|
|
out_disable_pclk:
|
|
clk_disable_unprepare(dw_wdt->pclk);
|
|
|
|
out_disable_clk:
|
|
clk_disable_unprepare(dw_wdt->clk);
|
|
return ret;
|
|
}
|
|
|
|
static int dw_wdt_drv_remove(struct platform_device *pdev)
|
|
{
|
|
struct dw_wdt *dw_wdt = platform_get_drvdata(pdev);
|
|
|
|
dw_wdt_dbgfs_clear(dw_wdt);
|
|
|
|
watchdog_unregister_device(&dw_wdt->wdd);
|
|
reset_control_assert(dw_wdt->rst);
|
|
clk_disable_unprepare(dw_wdt->pclk);
|
|
clk_disable_unprepare(dw_wdt->clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id dw_wdt_of_match[] = {
|
|
{ .compatible = "snps,dw-wdt", },
|
|
{ /* sentinel */ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, dw_wdt_of_match);
|
|
#endif
|
|
|
|
static struct platform_driver dw_wdt_driver = {
|
|
.probe = dw_wdt_drv_probe,
|
|
.remove = dw_wdt_drv_remove,
|
|
.driver = {
|
|
.name = "dw_wdt",
|
|
.of_match_table = of_match_ptr(dw_wdt_of_match),
|
|
.pm = &dw_wdt_pm_ops,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(dw_wdt_driver);
|
|
|
|
MODULE_AUTHOR("Jamie Iles");
|
|
MODULE_DESCRIPTION("Synopsys DesignWare Watchdog Driver");
|
|
MODULE_LICENSE("GPL");
|