blob: 98fdb3ffc59124e608be4f13fe6c9365b69176c5 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Xilinx AXI platforms watchdog timer driver.
*
* Author(s): Michal Simek <michal.simek@xilinx.com>
* Shreenidhi Shedi <yesshedi@gmail.com>
*
* Copyright (c) 2011-2018 Xilinx Inc.
*/
#include <common.h>
#include <dm.h>
#include <log.h>
#include <wdt.h>
#include <linux/err.h>
#include <linux/io.h>
#define XWT_CSR0_WRS_MASK 0x00000008 /* Reset status Mask */
#define XWT_CSR0_WDS_MASK 0x00000004 /* Timer state Mask */
#define XWT_CSR0_EWDT1_MASK 0x00000002 /* Enable bit 1 Mask*/
#define XWT_CSRX_EWDT2_MASK 0x00000001 /* Enable bit 2 Mask */
struct watchdog_regs {
u32 twcsr0; /* 0x0 */
u32 twcsr1; /* 0x4 */
u32 tbr; /* 0x8 */
};
struct xlnx_wdt_platdata {
bool enable_once;
struct watchdog_regs *regs;
};
static int xlnx_wdt_reset(struct udevice *dev)
{
u32 reg;
struct xlnx_wdt_platdata *plat = dev_get_plat(dev);
debug("%s ", __func__);
/* Read the current contents of TCSR0 */
reg = readl(&plat->regs->twcsr0);
/* Clear the watchdog WDS bit */
if (reg & (XWT_CSR0_EWDT1_MASK | XWT_CSRX_EWDT2_MASK))
writel(reg | XWT_CSR0_WDS_MASK, &plat->regs->twcsr0);
return 0;
}
static int xlnx_wdt_stop(struct udevice *dev)
{
u32 reg;
struct xlnx_wdt_platdata *plat = dev_get_plat(dev);
if (plat->enable_once) {
debug("Can't stop Xilinx watchdog.\n");
return -EBUSY;
}
/* Read the current contents of TCSR0 */
reg = readl(&plat->regs->twcsr0);
writel(reg & ~XWT_CSR0_EWDT1_MASK, &plat->regs->twcsr0);
writel(~XWT_CSRX_EWDT2_MASK, &plat->regs->twcsr1);
debug("Watchdog disabled!\n");
return 0;
}
static int xlnx_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
{
struct xlnx_wdt_platdata *plat = dev_get_plat(dev);
debug("%s:\n", __func__);
writel((XWT_CSR0_WRS_MASK | XWT_CSR0_WDS_MASK | XWT_CSR0_EWDT1_MASK),
&plat->regs->twcsr0);
writel(XWT_CSRX_EWDT2_MASK, &plat->regs->twcsr1);
return 0;
}
static int xlnx_wdt_probe(struct udevice *dev)
{
debug("%s: Probing wdt%u\n", __func__, dev->seq);
return 0;
}
static int xlnx_wdt_of_to_plat(struct udevice *dev)
{
struct xlnx_wdt_platdata *plat = dev_get_plat(dev);
plat->regs = (struct watchdog_regs *)dev_read_addr(dev);
if (IS_ERR(plat->regs))
return PTR_ERR(plat->regs);
plat->enable_once = dev_read_u32_default(dev, "xlnx,wdt-enable-once",
0);
debug("%s: wdt-enable-once %d\n", __func__, plat->enable_once);
return 0;
}
static const struct wdt_ops xlnx_wdt_ops = {
.start = xlnx_wdt_start,
.reset = xlnx_wdt_reset,
.stop = xlnx_wdt_stop,
};
static const struct udevice_id xlnx_wdt_ids[] = {
{ .compatible = "xlnx,xps-timebase-wdt-1.00.a", },
{ .compatible = "xlnx,xps-timebase-wdt-1.01.a", },
{},
};
U_BOOT_DRIVER(xlnx_wdt) = {
.name = "xlnx_wdt",
.id = UCLASS_WDT,
.of_match = xlnx_wdt_ids,
.probe = xlnx_wdt_probe,
.plat_auto = sizeof(struct xlnx_wdt_platdata),
.of_to_plat = xlnx_wdt_of_to_plat,
.ops = &xlnx_wdt_ops,
};