cpu.c.svn-base

来自「RT-Thread是发展中的下一代微内核嵌入式实时操作系统」· SVN-BASE 代码 · 共 137 行

/*
 * File      : cpu.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2006, RT-Thread Develop Team
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://openlab.rt-thread.com/license/LICENSE.
 *
 * Change Logs:
 * Date           Author       Notes
 * 2006-10-24     Bernard      first version
 */

#include <rtthread.h>
#include "pxa270.h"

/**
 * @addtogroup PXA270
 */
/*@{*/

/**
 * this function will enable I-Cache of CPU
 */
void rt_hw_cpu_icache_enable()
{
	register rt_uint32 i;

	/* read control register */
	asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));

	/* set i-cache */
	i |= 0x1000;

	/* write back to control register */
	asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
}

/**
 * @brief disable I-Cache of cpu
 *
 * this function will disable I-Cache of CPU
 *
 */
void rt_hw_cpu_icache_disable()
{
	register rt_uint32 i;

	/* read control register */
	asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));

	/* clear i-cache */
	i &= ~0x1000;

	/* write back to control register */
	asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));

	/* flush i-cache */
	asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
}

/**
 * @brief get the status of I-Cache
 *
 * this function will get the status of I-Cache
 *
 */
int rt_hw_cpu_icache_status()
{
	register rt_uint32 i;

	/* read control register */
	asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));

	/* return bit */
	return (i & 0x1000);
}

/**
 * @brief enable D-Cache of cpu
 *
 * this function will enable D-Cache of CPU
 *
 */
void rt_hw_cpu_dcache_enable(void)
{
	return;
}

/**
 * @brief disable D-Cache of cpu
 *
 * this function will disable D-Cache of CPU
 *
 */
void rt_hw_cpu_dcache_disable(void)
{
	return;
}

/**
 * @brief get the status of D-Cache
 *
 * this function will get the status of D-Cache
 *
 */
int rt_hw_cpu_dcache_status(void)
{
	return 0;
}

/**
 * @brief reset CPU
 *
 * this function will reset CPU
 *
 */
void rt_hw_cpu_reset()
{
}

/**
 * @brief shutdown CPU
 *
 * this function will shutdown CPU
 *
 */
void rt_hw_cpu_shutdown()
{
	rt_kprintf("shutdown...\n");

	while (1);
}

/*@}*/