blob: 358a9b90fddbd6daa2abd7618ce81d5d43995c06 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2017 Intel Corporation
*/
#include <common.h>
#include <dm.h>
#include <log.h>
#include <wdt.h>
#include <div64.h>
#include <asm/scu.h>
/* Hardware timeout in seconds */
#define WDT_PRETIMEOUT 15
#define WDT_TIMEOUT_MIN (1 + WDT_PRETIMEOUT)
#define WDT_TIMEOUT_MAX 170
/*
* Note, firmware chooses 90 seconds as a default timeout for watchdog on
* Intel Tangier SoC. It means that without handling it in the running code
* the reboot will happen.
*/
enum {
SCU_WATCHDOG_START = 0,
SCU_WATCHDOG_STOP = 1,
SCU_WATCHDOG_KEEPALIVE = 2,
SCU_WATCHDOG_SET_ACTION_ON_TIMEOUT = 3,
};
static int tangier_wdt_reset(struct udevice *dev)
{
scu_ipc_simple_command(IPCMSG_WATCHDOG_TIMER, SCU_WATCHDOG_KEEPALIVE);
return 0;
}
static int tangier_wdt_stop(struct udevice *dev)
{
return scu_ipc_simple_command(IPCMSG_WATCHDOG_TIMER, SCU_WATCHDOG_STOP);
}
static int tangier_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
{
u32 timeout_sec;
int in_size;
struct ipc_wd_start {
u32 pretimeout;
u32 timeout;
} ipc_wd_start;
/* Calculate timeout in seconds and restrict to min and max value */
do_div(timeout_ms, 1000);
timeout_sec = clamp_t(u32, timeout_ms, WDT_TIMEOUT_MIN, WDT_TIMEOUT_MAX);
/* Update values in the IPC request */
ipc_wd_start.pretimeout = timeout_sec - WDT_PRETIMEOUT;
ipc_wd_start.timeout = timeout_sec;
/*
* SCU expects the input size for watchdog IPC
* to be based on 4 bytes
*/
in_size = DIV_ROUND_UP(sizeof(ipc_wd_start), 4);
scu_ipc_command(IPCMSG_WATCHDOG_TIMER, SCU_WATCHDOG_START,
(u32 *)&ipc_wd_start, in_size, NULL, 0);
return 0;
}
static const struct wdt_ops tangier_wdt_ops = {
.reset = tangier_wdt_reset,
.start = tangier_wdt_start,
.stop = tangier_wdt_stop,
};
static const struct udevice_id tangier_wdt_ids[] = {
{ .compatible = "intel,tangier-wdt" },
{ /* sentinel */ }
};
static int tangier_wdt_probe(struct udevice *dev)
{
debug("%s: Probing wdt%u\n", __func__, dev->seq);
return 0;
}
U_BOOT_DRIVER(wdt_tangier) = {
.name = "wdt_tangier",
.id = UCLASS_WDT,
.of_match = tangier_wdt_ids,
.ops = &tangier_wdt_ops,
.probe = tangier_wdt_probe,
};