ppcv_map_booke.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"

// We're going to use PID == 0 for callout mappings and
// PID == 1 for startup ones.

void *
ppcv_map_booke(unsigned size, paddr_t phys, unsigned prot_flags) {
	unsigned			i;
	unsigned			free = -1;
	ppcbke_tlb_t		tlb;
	uint64_t			tlb_size;
	paddr64_t			paddr;
	paddr64_t			end;
	unsigned			access;
	static uintptr_t	next_vaddr = 0x80000000;
	unsigned			tlb_num;
	unsigned			supported;

	paddr = phys;

#if 0
//NYI: TEMP TESTING HACK
return((void *)(uintptr_t)paddr);
#endif
	end = paddr + size - 1;
	if((end < MEG(256)) && ((prot_flags & (PROT_CALLOUT|PROT_NOCACHE)) == 0)) {
		// A cachable startup request in the first 256M of memory.
		// Can just use the one-to-one mapping.
		return((void *)(uintptr_t)paddr);
	}
	supported = 0;
	i = 0;
	tlb_num = 0;
	for(;;) {
		int		curr;

		curr = ppcbke_tlb.info(MI_PAGESIZES, i);
		if(curr < 0) break;
		if(curr > supported) {
			// We want to use the TLB with the greatest # of supported sizes.
			// Not exactly what we're testing for here, but close enough
			// for jazz.
			supported = curr;
			tlb_num = i;
		}
		++i;
	}
	for(i = ppcbke_tlb.info(MI_NUM_ENTRIES, tlb_num); i > 0; --i) {
		ppcbke_tlb.read(tlb_num, i, &tlb);
		if(tlb.v) {
			tlb_size = (uint64_t)0x400 << (tlb.size*2);
			if((tlb.rpn <= paddr) && (end < (tlb.rpn + tlb_size))) {
				if(!(prot_flags & PROT_NOCACHE) || (tlb.attr & PPCBKE_TLB_ATTR_I)) {
					// We can reuse this TLB entry.
					if((prot_flags & PROT_CALLOUT) && (tlb.tid != 0)) {
						//It's a startup mapping, we need to make it a callout one.
						tlb.tid = 0;
						ppcbke_tlb.write(tlb_num, i, &tlb);
					}
					return (void *)(tlb.epn + (uintptr_t)(paddr - tlb.rpn));
				}
			}
		} else {
			free = i;
		}
	}
	if(free == -1) {
		crash("No TLB to map 0x%L for %d bytes.\n", paddr, size);
	}
	supported = ppcbke_tlb.info(MI_PAGESIZES, tlb_num);
	i = PPCBKE_TLB_SIZE_1K;
	for( ;; ) {
		if(i > PPCBKE_TLB_SIZE_1T) {
			crash("No supported TLB size to map 0x%L for %d bytes.\n", paddr, size);
		}
		if(supported & (1 << i)) {
			tlb_size = (uint64_t)0x400 * (1 << (i*2));
			tlb.rpn = paddr & ~(tlb_size - 1);
			if(end < (tlb.rpn + tlb_size)) break;
		}
		++i;
	}
	tlb.size = i;
	tlb.epn = (next_vaddr + ((uintptr_t)tlb_size-1)) & ~((uintptr_t)tlb_size-1);
	next_vaddr = tlb.epn + (uintptr_t)tlb_size;
	tlb.tid = (prot_flags & PROT_CALLOUT) ? 0 : 1;
	tlb.attr = PPCBKEM_TLB_ATTR_SHAREN | PPCBKEM_TLB_ATTR_IPROT;
	if(prot_flags & PROT_NOCACHE) {
		tlb.attr |= PPCBKE_TLB_ATTR_I|PPCBKE_TLB_ATTR_G;
	}
	access = 0;
	if(prot_flags & PROT_READ)  access |= PPCBKE_TLB_ACCESS_SR;
	if(prot_flags & PROT_WRITE) access |= PPCBKE_TLB_ACCESS_SW;
	if(prot_flags & PROT_EXEC)  access |= PPCBKE_TLB_ACCESS_SX;
	if(prot_flags & PROT_USER)  access |= (access << 3);
	tlb.access = access;
	tlb.ts = 0;
	tlb.v = 1;
	ppcbke_tlb.write(tlb_num, free, &tlb);
	return (void *)(tlb.epn + (uintptr_t)(paddr - tlb.rpn));
}