cache.c

日本著名的的嵌入式实时操作系统T-Kernel的源码及用户手册。

/*
 *----------------------------------------------------------------------
 *    T-Kernel
 *
 *    Copyright (C) 2004 by Ken Sakamura. All rights reserved.
 *    T-Kernel is distributed under the T-License.
 *----------------------------------------------------------------------
 *
 *    Version:   1.01.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2004/6/28.
 *
 *----------------------------------------------------------------------
 */

/*
 *	cache.c (VR4131)
 *	Cache Flush Range
 */

#include <basic.h>
#include <tk/tkernel.h>
#include "cache_asm.h"

/*
 * Cache line size (byte)
 */
EXPORT	W	ICacheLineSize;		/* Instruction cache */
EXPORT	W	DCacheLineSize;		/* Data cache */

/*
 * Cache flush
 *	Flush cache between 'laddr' and 'size' bytes areas.
 */
EXPORT void FlushCache( VP laddr, W size )
{
	VP	la  = (VP)((UW)laddr & ~(CACHE_BLOCK_SIZE - 1));
	VP	end = (B*)laddr + size;

	/* Get cache line size */
	UW	cfg;
	Asm("mfc0 %0, $16": "=r"(cfg));	/* Read config register */
	ICacheLineSize = ( (cfg & 0x20) != 0 )? 32: 16;
	DCacheLineSize = ( (cfg & 0x10) != 0 )? 32: 16;

	while ( la < end ) {
		FlushCacheOneBlock(la);
		la += CACHE_BLOCK_SIZE;
		if ( la >= end ) break;
	}

	return;
}