set_spr_indirect.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"

void
set_spr_indirect(unsigned spr, unsigned value) {
	unsigned	instrs[2];

	spr = (spr >> 5) | ((spr & 0x1f) << 5);
	instrs[0] = 0x7c6003a6 | (spr << 11); 	// mtspr SPR,%r3
	instrs[1] = 0x4e800020;					// blr

	// flush both in case we're crossing a cache boundry.
	icache_flush(&instrs[0]);
	icache_flush(&instrs[1]);

	((void (*)(unsigned))instrs)(value);
}