u-boot/arch/arm/cpu/arm946es/cpu.c

/*
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Marius Groeger <mgroeger@sysgo.de>
 *
 * (C) Copyright 2002
 * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * CPU specific code
 */

#include <common.h>
#include <command.h>
#include <asm/system.h>

static void cache_flush(void);

int cleanup_before_linux (void)
{
	/*
	 * this function is called just before we call linux
	 * it prepares the processor for linux
	 *
	 * we turn off caches etc ...
	 */

	disable_interrupts ();

	/* ARM926E-S needs the protection unit enabled for the icache to have
	 * been enabled	 - left for possible later use
	 * should turn off the protection unit as well....
	 */
	/* turn off I/D-cache */
	icache_disable();
	dcache_disable();
	/* flush I/D-cache */
	cache_flush();

	return 0;
}

/* flush I/D-cache */
static void cache_flush (void)
{
	unsigned long i = 0;

	asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
	asm ("mcr p15, 0, %0, c7, c6, 0": :"r" (i));
}