u-boot/drivers/watchdog/octeontx_wdt.c
Stefan Roese 1aa2b85810 watchdog: octeontx_wdt: Add MIPS Octeon support
This patch adds support for the Marvell Octeon watchdog driver, which
currently only support the ARM64 Octeon TX & TX2 platforms. Since the
IP is pretty similar, it makes sense to extend this driver to also
support the MIPS Octeon SoC.

A follow-up patch will enable this watchdog support on the EBB7304
eval board.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Aaron Williams <awilliams@marvell.com>
Cc: Chandrakala Chavva <cchavva@marvell.com>
2022-07-21 08:09:06 +02:00

176 lines
3.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2019 Marvell International Ltd.
*
* https://spdx.org/licenses
*/
#include <clk.h>
#include <dm.h>
#include <errno.h>
#include <wdt.h>
#include <asm/global_data.h>
#include <asm/io.h>
#include <linux/bitfield.h>
DECLARE_GLOBAL_DATA_PTR;
#define CORE0_POKE_OFFSET_MASK 0xfffffULL
#define WDOG_MODE GENMASK_ULL(1, 0)
#define WDOG_LEN GENMASK_ULL(19, 4)
#define WDOG_CNT GENMASK_ULL(43, 20)
struct octeontx_wdt_data {
u32 wdog_offset;
u32 poke_offset;
int timer_shift;
bool has_clk;
};
struct octeontx_wdt {
void __iomem *reg;
const struct octeontx_wdt_data *data;
struct clk clk;
};
static int octeontx_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
{
struct octeontx_wdt *priv = dev_get_priv(dev);
u64 clk_rate, val;
u64 tout_wdog;
if (priv->data->has_clk) {
clk_rate = clk_get_rate(&priv->clk);
if (IS_ERR_VALUE(clk_rate))
return -EINVAL;
} else {
clk_rate = gd->bus_clk;
}
/* Watchdog counts in configured cycle steps */
tout_wdog = (clk_rate * timeout_ms / 1000) >> priv->data->timer_shift;
/*
* We can only specify the upper 16 bits of a 24 bit value.
* Round up
*/
tout_wdog = (tout_wdog + 0xff) >> 8;
/* If the timeout overflows the hardware limit, set max */
if (tout_wdog >= 0x10000)
tout_wdog = 0xffff;
val = FIELD_PREP(WDOG_MODE, 0x3) |
FIELD_PREP(WDOG_LEN, tout_wdog) |
FIELD_PREP(WDOG_CNT, tout_wdog << 8);
writeq(val, priv->reg + priv->data->wdog_offset);
return 0;
}
static int octeontx_wdt_stop(struct udevice *dev)
{
struct octeontx_wdt *priv = dev_get_priv(dev);
writeq(0, priv->reg + priv->data->wdog_offset);
return 0;
}
static int octeontx_wdt_expire_now(struct udevice *dev, ulong flags)
{
octeontx_wdt_stop(dev);
/* Start with 100ms timeout to expire immediately */
octeontx_wdt_start(dev, 100, flags);
return 0;
}
static int octeontx_wdt_reset(struct udevice *dev)
{
struct octeontx_wdt *priv = dev_get_priv(dev);
writeq(~0ULL, priv->reg + priv->data->poke_offset);
return 0;
}
static int octeontx_wdt_remove(struct udevice *dev)
{
octeontx_wdt_stop(dev);
return 0;
}
static int octeontx_wdt_probe(struct udevice *dev)
{
struct octeontx_wdt *priv = dev_get_priv(dev);
int ret;
priv->reg = dev_remap_addr(dev);
if (!priv->reg)
return -EINVAL;
priv->data = (void *)dev_get_driver_data(dev);
if (!priv->data)
return -EINVAL;
/*
* Save base register address in reg masking lower 20 bits
* as 0xa0000 appears when extracted from the DT
*/
priv->reg = (void __iomem *)(((u64)priv->reg &
~CORE0_POKE_OFFSET_MASK));
if (priv->data->has_clk) {
ret = clk_get_by_index(dev, 0, &priv->clk);
if (ret < 0)
return ret;
ret = clk_enable(&priv->clk);
if (ret)
return ret;
}
return 0;
}
static const struct wdt_ops octeontx_wdt_ops = {
.reset = octeontx_wdt_reset,
.start = octeontx_wdt_start,
.stop = octeontx_wdt_stop,
.expire_now = octeontx_wdt_expire_now,
};
static const struct octeontx_wdt_data octeontx_data = {
.wdog_offset = 0x40000,
.poke_offset = 0x50000,
.timer_shift = 10,
.has_clk = true,
};
static const struct octeontx_wdt_data octeon_data = {
.wdog_offset = 0x20000,
.poke_offset = 0x30000,
.timer_shift = 10,
.has_clk = false,
};
static const struct udevice_id octeontx_wdt_ids[] = {
{ .compatible = "arm,sbsa-gwdt", .data = (ulong)&octeontx_data },
{ .compatible = "cavium,octeon-7890-ciu3", .data = (ulong)&octeon_data },
{}
};
U_BOOT_DRIVER(wdt_octeontx) = {
.name = "wdt_octeontx",
.id = UCLASS_WDT,
.of_match = octeontx_wdt_ids,
.ops = &octeontx_wdt_ops,
.priv_auto = sizeof(struct octeontx_wdt),
.probe = octeontx_wdt_probe,
.remove = octeontx_wdt_remove,
.flags = DM_FLAG_OS_PREPARE,
};