u-boot-brain/arch/arm/cpu/arm926ejs/mx25/reset.c
Harald Seiler 35b65dd8ef reset: Remove addr parameter from reset_cpu()
Historically, the reset_cpu() function had an `addr` parameter which was
meant to pass in an address of the reset vector location, where the CPU
should reset to.  This feature is no longer used anywhere in U-Boot as
all reset_cpu() implementations now ignore the passed value.  Generic
code has been added which always calls reset_cpu() with `0` which means
this feature can no longer be used easily anyway.

Over time, many implementations seem to have "misunderstood" the
existence of this parameter as a way to customize/parameterize the reset
(e.g.  COLD vs WARM resets).  As this is not properly supported, the
code will almost always not do what it is intended to (because all
call-sites just call reset_cpu() with 0).

To avoid confusion and to clean up the codebase from unused left-overs
of the past, remove the `addr` parameter entirely.  Code which intends
to support different kinds of resets should be rewritten as a sysreset
driver instead.

This transformation was done with the following coccinelle patch:

    @@
    expression argvalue;
    @@
    - reset_cpu(argvalue)
    + reset_cpu()

    @@
    identifier argname;
    type argtype;
    @@
    - reset_cpu(argtype argname)
    + reset_cpu(void)
    { ... }

Signed-off-by: Harald Seiler <hws@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
2021-03-02 14:03:02 -05:00

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C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Alex Zuepke <azu@sysgo.de>
*
* (C) Copyright 2002
* Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
*
* (C) Copyright 2009
* Ilya Yanok, Emcraft Systems Ltd, <yanok@emcraft.com>
*/
#include <common.h>
#include <cpu_func.h>
#include <asm/io.h>
#include <asm/arch/imx-regs.h>
/*
* Reset the cpu by setting up the watchdog timer and let it time out
*/
void reset_cpu(void)
{
struct wdog_regs *regs = (struct wdog_regs *)IMX_WDT_BASE;
/* Disable watchdog and set Time-Out field to 0 */
writew(0, &regs->wcr);
/* Write Service Sequence */
writew(WSR_UNLOCK1, &regs->wsr);
writew(WSR_UNLOCK2, &regs->wsr);
/* Enable watchdog */
writew(WCR_WDE, &regs->wcr);
while (1) ;
}