ppc7450_init_l3_cache.c

qnx powerpc MPC8245的 BSP源文件

/*
 * $QNXLicenseC: 
 * Copyright 2007, QNX Software Systems.  
 *  
 * Licensed under the Apache License, Version 2.0 (the "License"). You  
 * may not reproduce, modify or distribute this software except in  
 * compliance with the License. You may obtain a copy of the License  
 * at: http://www.apache.org/licenses/LICENSE-2.0  
 *  
 * Unless required by applicable law or agreed to in writing, software  
 * distributed under the License is distributed on an "AS IS" basis,  
 * WITHOUT WARRANTIES OF ANY KIND, either express or implied. 
 * 
 * This file may contain contributions from others, either as  
 * contributors under the License or as licensors under other terms.   
 * Please review this entire file for other proprietary rights or license  
 * notices, as well as the QNX Development Suite License Guide at  
 * http://licensing.qnx.com/license-guide/ for other information. 
 * $ 
 */

#include "startup.h"
#include <ppc/603cpu.h>
#include <ppc/700cpu.h>

// Init the L3 cache on PPC7450 family chips. 

void ppc7450_init_l3_cache(unsigned flags) {
	unsigned l3cr, l3bits, tmp;

	// Mask off flag bits we don't need
	// Enable, clock on, flush
	tmp = ~(0x88000800) & flags;

	l3bits = 0x04000000; // Magic bit (errata)
	l3bits |= tmp; 		// passed-in flags

	l3cr = 0;

	set_spr(1018,l3cr);
	set_spr(1018,l3bits);
	asm("sync");
	l3cr = l3bits | 0x08000000; //CLKEN
	asm("sync");
	set_spr(1018,l3cr);
	asm("sync");

	// Not sure if this delay is really needed -- it's in the
	// DINK init code
	tmp = 0x200000; while(--tmp) asm("nop");
	asm("sync");
	set_spr(1018,l3cr|0x0400); // L3I
	asm("sync");

	// Wait for invalidate to finish
	while(get_spr(1018) & 0x0400);
	asm("sync");

	// Not sure again if this is really needed
	tmp = 0x20000; while(--tmp) asm("nop");
	set_spr(1018,l3bits);
	asm("sync");
	// Not sure if this is really needed
	tmp = 0x200000; while(--tmp) asm("nop");

	// OR-in clock enable and cache enable bits then turn on
	l3cr = l3bits | 0x88000000; //CLKEN|L3E
	asm("sync");
	set_spr(1018,l3cr);
	asm("sync");
	tmp = 0x200000; while(--tmp) asm("nop");

	// We're done!
}