u-boot/drivers/watchdog/omap_wdt.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

136 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* omap_wdt.c
*
* (C) Copyright 2013
* Heiko Schocher, DENX Software Engineering, hs@denx.de.
*
* Based on:
*
* Watchdog driver for the TI OMAP 16xx & 24xx/34xx 32KHz (non-secure) watchdog
*
* commit 2d991a164a61858012651e13c59521975504e260
* Author: Bill Pemberton <wfp5p@virginia.edu>
* Date: Mon Nov 19 13:21:41 2012 -0500
*
* watchdog: remove use of __devinit
*
* CONFIG_HOTPLUG is going away as an option so __devinit is no longer
* needed.
*
* Author: MontaVista Software, Inc.
* <gdavis@mvista.com> or <source@mvista.com>
*
* History:
*
* 20030527: George G. Davis <gdavis@mvista.com>
* Initially based on linux-2.4.19-rmk7-pxa1/drivers/char/sa1100_wdt.c
* (c) Copyright 2000 Oleg Drokin <green@crimea.edu>
* Based on SoftDog driver by Alan Cox <alan@lxorguk.ukuu.org.uk>
*
* Copyright (c) 2004 Texas Instruments.
* 1. Modified to support OMAP1610 32-KHz watchdog timer
* 2. Ported to 2.6 kernel
*
* Copyright (c) 2005 David Brownell
* Use the driver model and standard identifiers; handle bigger timeouts.
*/
#include <common.h>
#include <watchdog.h>
#include <asm/arch/hardware.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/arch/cpu.h>
/* Hardware timeout in seconds */
#define WDT_HW_TIMEOUT 60
static unsigned int wdt_trgr_pattern = 0x1234;
void hw_watchdog_reset(void)
{
struct wd_timer *wdt = (struct wd_timer *)WDT_BASE;
/*
* Somebody just triggered watchdog reset and write to WTGR register
* is in progress. It is resetting right now, no need to trigger it
* again
*/
if ((readl(&wdt->wdtwwps)) & WDT_WWPS_PEND_WTGR)
return;
wdt_trgr_pattern = ~wdt_trgr_pattern;
writel(wdt_trgr_pattern, &wdt->wdtwtgr);
/*
* Don't wait for posted write to complete, i.e. don't check
* WDT_WWPS_PEND_WTGR bit in WWPS register. There is no writes to
* WTGR register outside of this func, and if entering it
* we see WDT_WWPS_PEND_WTGR bit set, it means watchdog reset
* was just triggered. This prevents us from wasting time in busy
* polling of WDT_WWPS_PEND_WTGR bit.
*/
}
static int omap_wdt_set_timeout(unsigned int timeout)
{
struct wd_timer *wdt = (struct wd_timer *)WDT_BASE;
u32 pre_margin = GET_WLDR_VAL(timeout);
/* just count up at 32 KHz */
while (readl(&wdt->wdtwwps) & WDT_WWPS_PEND_WLDR)
;
writel(pre_margin, &wdt->wdtwldr);
while (readl(&wdt->wdtwwps) & WDT_WWPS_PEND_WLDR)
;
return 0;
}
void hw_watchdog_disable(void)
{
struct wd_timer *wdt = (struct wd_timer *)WDT_BASE;
/*
* Disable watchdog
*/
writel(0xAAAA, &wdt->wdtwspr);
while (readl(&wdt->wdtwwps) != 0x0)
;
writel(0x5555, &wdt->wdtwspr);
while (readl(&wdt->wdtwwps) != 0x0)
;
}
void hw_watchdog_init(void)
{
struct wd_timer *wdt = (struct wd_timer *)WDT_BASE;
/*
* Make sure the watchdog is disabled. This is unfortunately required
* because writing to various registers with the watchdog running has no
* effect.
*/
hw_watchdog_disable();
/* initialize prescaler */
while (readl(&wdt->wdtwwps) & WDT_WWPS_PEND_WCLR)
;
writel(WDT_WCLR_PRE | (PTV << WDT_WCLR_PTV_OFF), &wdt->wdtwclr);
while (readl(&wdt->wdtwwps) & WDT_WWPS_PEND_WCLR)
;
omap_wdt_set_timeout(WDT_HW_TIMEOUT);
/* Sequence to enable the watchdog */
writel(0xBBBB, &wdt->wdtwspr);
while ((readl(&wdt->wdtwwps)) & WDT_WWPS_PEND_WSPR)
;
writel(0x4444, &wdt->wdtwspr);
while ((readl(&wdt->wdtwwps)) & WDT_WWPS_PEND_WSPR)
;
}