u-boot/drivers/watchdog/sbsa_gwdt.c
Simon Glass 8b85dfc675 dm: Avoid accessing seq directly
At present various drivers etc. access the device's 'seq' member directly.
This makes it harder to change the meaning of that member. Change access
to go through a function instead.

The drivers/i2c/lpc32xx_i2c.c file is left unchanged for now.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-12-18 20:32:21 -07:00

131 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Watchdog driver for SBSA
*
* Copyright 2020 NXP
*/
#include <asm/io.h>
#include <common.h>
#include <dm/device.h>
#include <dm/fdtaddr.h>
#include <dm/read.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <watchdog.h>
#include <wdt.h>
DECLARE_GLOBAL_DATA_PTR;
/* SBSA Generic Watchdog register definitions */
/* refresh frame */
#define SBSA_GWDT_WRR 0x000
/* control frame */
#define SBSA_GWDT_WCS 0x000
#define SBSA_GWDT_WOR 0x008
#define SBSA_GWDT_WCV 0x010
/* refresh/control frame */
#define SBSA_GWDT_W_IIDR 0xfcc
#define SBSA_GWDT_IDR 0xfd0
/* Watchdog Control and Status Register */
#define SBSA_GWDT_WCS_EN BIT(0)
#define SBSA_GWDT_WCS_WS0 BIT(1)
#define SBSA_GWDT_WCS_WS1 BIT(2)
struct sbsa_gwdt_priv {
void __iomem *reg_refresh;
void __iomem *reg_control;
};
static int sbsa_gwdt_reset(struct udevice *dev)
{
struct sbsa_gwdt_priv *priv = dev_get_priv(dev);
writel(0, priv->reg_refresh + SBSA_GWDT_WRR);
return 0;
}
static int sbsa_gwdt_start(struct udevice *dev, u64 timeout, ulong flags)
{
struct sbsa_gwdt_priv *priv = dev_get_priv(dev);
u32 clk;
/*
* it work in the single stage mode in u-boot,
* The first signal (WS0) is ignored,
* the timeout is (WOR * 2), so the WOR should be configured
* to half value of timeout.
*/
clk = get_tbclk();
writel(clk / 2 * timeout,
priv->reg_control + SBSA_GWDT_WOR);
/* writing WCS will cause an explicit watchdog refresh */
writel(SBSA_GWDT_WCS_EN, priv->reg_control + SBSA_GWDT_WCS);
return 0;
}
static int sbsa_gwdt_stop(struct udevice *dev)
{
struct sbsa_gwdt_priv *priv = dev_get_priv(dev);
writel(0, priv->reg_control + SBSA_GWDT_WCS);
return 0;
}
static int sbsa_gwdt_expire_now(struct udevice *dev, ulong flags)
{
sbsa_gwdt_start(dev, 0, flags);
return 0;
}
static int sbsa_gwdt_probe(struct udevice *dev)
{
debug("%s: Probing wdt%u (sbsa-gwdt)\n", __func__, dev_seq(dev));
return 0;
}
static int sbsa_gwdt_of_to_plat(struct udevice *dev)
{
struct sbsa_gwdt_priv *priv = dev_get_priv(dev);
priv->reg_control = (void __iomem *)dev_read_addr_index(dev, 0);
if (IS_ERR(priv->reg_control))
return PTR_ERR(priv->reg_control);
priv->reg_refresh = (void __iomem *)dev_read_addr_index(dev, 1);
if (IS_ERR(priv->reg_refresh))
return PTR_ERR(priv->reg_refresh);
return 0;
}
static const struct wdt_ops sbsa_gwdt_ops = {
.start = sbsa_gwdt_start,
.reset = sbsa_gwdt_reset,
.stop = sbsa_gwdt_stop,
.expire_now = sbsa_gwdt_expire_now,
};
static const struct udevice_id sbsa_gwdt_ids[] = {
{ .compatible = "arm,sbsa-gwdt" },
{}
};
U_BOOT_DRIVER(sbsa_gwdt) = {
.name = "sbsa_gwdt",
.id = UCLASS_WDT,
.of_match = sbsa_gwdt_ids,
.probe = sbsa_gwdt_probe,
.priv_auto = sizeof(struct sbsa_gwdt_priv),
.of_to_plat = sbsa_gwdt_of_to_plat,
.ops = &sbsa_gwdt_ops,
};