u-boot/arch/arm/cpu/arm1136/cpu.c

/*
 * (C) Copyright 2004 Texas Insturments
 *
 * (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>
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

/*
 * 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 ();

#ifdef CONFIG_LCD
	{
		extern void lcd_disable(void);
		extern void lcd_panel_disable(void);

		lcd_disable(); /* proper disable of lcd & panel */
		lcd_panel_disable();
	}
#endif

	/* turn off I/D-cache */
	icache_disable();
	dcache_disable();
	/* flush I/D-cache */
	cache_flush();

	return 0;
}

static void cache_flush(void)
{
	unsigned long i = 0;

	asm ("mcr p15, 0, %0, c7, c10, 0": :"r" (i)); /* clean entire data cache */
	asm ("mcr p15, 0, %0, c7, c7, 0": :"r" (i));  /* invalidate both caches and flush btb */
	asm ("mcr p15, 0, %0, c7, c10, 4": :"r" (i)); /* mem barrier to sync things */
}

#ifndef CONFIG_SYS_DCACHE_OFF

#ifndef CONFIG_SYS_CACHELINE_SIZE
#define CONFIG_SYS_CACHELINE_SIZE	32
#endif

void invalidate_dcache_all(void)
{
	asm ("mcr p15, 0, %0, c7, c6, 0" : : "r" (0));
}

void flush_dcache_all(void)
{
	asm ("mcr p15, 0, %0, c7, c10, 0" : : "r" (0));
	asm ("mcr p15, 0, %0, c7, c10, 4" : : "r" (0));
}

static inline int bad_cache_range(unsigned long start, unsigned long stop)
{
	int ok = 1;

	if (start & (CONFIG_SYS_CACHELINE_SIZE - 1))
		ok = 0;

	if (stop & (CONFIG_SYS_CACHELINE_SIZE - 1))
		ok = 0;

	if (!ok)
		debug("CACHE: Misaligned operation at range [%08lx, %08lx]\n",
			start, stop);

	return ok;
}

void invalidate_dcache_range(unsigned long start, unsigned long stop)
{
	if (bad_cache_range(start, stop))
		return;

	while (start < stop) {
		asm ("mcr p15, 0, %0, c7, c6, 1" : : "r" (start));
		start += CONFIG_SYS_CACHELINE_SIZE;
	}
}

void flush_dcache_range(unsigned long start, unsigned long stop)
{
	if (bad_cache_range(start, stop))
		return;

	while (start < stop) {
		asm ("mcr p15, 0, %0, c7, c14, 1" : : "r" (start));
		start += CONFIG_SYS_CACHELINE_SIZE;
	}

	asm ("mcr p15, 0, %0, c7, c10, 4" : : "r" (0));
}

void flush_cache(unsigned long start, unsigned long size)
{
	flush_dcache_range(start, start + size);
}

void enable_caches(void)
{
#ifndef CONFIG_SYS_ICACHE_OFF
	icache_enable();
#endif
#ifndef CONFIG_SYS_DCACHE_OFF
	dcache_enable();
#endif
}

#else /* #ifndef CONFIG_SYS_DCACHE_OFF */
void invalidate_dcache_all(void)
{
}

void flush_dcache_all(void)
{
}

void invalidate_dcache_range(unsigned long start, unsigned long stop)
{
}

void flush_dcache_range(unsigned long start, unsigned long stop)
{
}

void flush_cache(unsigned long start, unsigned long size)
{
}
#endif /* #ifndef CONFIG_SYS_DCACHE_OFF */