arm_map.c

QNX ADS BSP code for i.MX27 chips

/*
 * $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"

/*
 * Map a 4K page table into both the L1 table and the "page directory"
 */
void
arm_ptmap(paddr_t pt, uintptr_t vaddr)
{
	int		i;
	pte_t	*pte = (pte_t *)L2_paddr + (vaddr >> 22);
	ptp_t	*ptp = (ptp_t *)L1_paddr + ((vaddr >> 20) & ~3);

	/*
	 * Map the page table into the "page directory" page table
	 */
	*pte = (pt | arm_pte_info->kpte_rw) & ~arm_pte_info->mask_nc;

	/*
	 * Map the page table into the L1 table
	 */
	for (i = 0; i < 4; i++, pt += ARM_L2_SIZE) {
		*ptp++ = pt | ARM_PTP_L2;
	}
}

/*
 * Map a 1MB section into the L1 table.
 * This should be used with care, since the "page directory" knows
 * nothing about these mappings. Currently this is used only to map
 * the startup code itself to switch the MMU translation on.
 */
void
arm_scmap(uintptr_t vaddr, paddr_t paddr, int flags)
{
	ptp_t	*ptp = (ptp_t *)L1_paddr + (vaddr >> 20);

	flags = (flags & ARM_PTE_CB) | ((flags & ARM_PTE_AP_MASK) << 10);
	*ptp = paddr | flags | ARM_PTP_SC;
}

/*
 * Map [paddr, paddr+size) with ARM specific attributes in flags.
 * If vaddr is ~0, we assign the address, otherwise, the mapping
 * will be made at the specified virtual address.
 */
paddr_t
arm_map(uintptr_t vaddr, paddr_t paddr, size_t size, int flags)
{
	static uintptr_t	next_addr = ARM_STARTUP_BASE;
	ptp_t				*ptp;
	paddr_t				off = paddr & PGMASK;

	if (!(shdr->flags1 & STARTUP_HDR_FLAGS1_VIRTUAL)) {
		return paddr;
	}

	paddr &= ~PGMASK;
	size = ROUNDPG(size + off);
	if (vaddr == ~(uintptr_t)0) {
		vaddr = next_addr;
		next_addr += size;
	}

	if (flags & ARM_PTE_U) {
		paddr |= (flags & ARM_PTE_RW) ? arm_pte_info->upte_rw
									  : arm_pte_info->upte_ro;
	}
	else {
		paddr |= (flags & ARM_PTE_RW) ? arm_pte_info->kpte_rw
									  : arm_pte_info->kpte_ro;
	}
	if ((flags & ARM_PTE_CB) == 0) {
		paddr &= ~arm_pte_info->mask_nc;
	}
	ptp = (ptp_t *)L1_paddr + ((vaddr >> 20) & ~3);

	while (size) {
		int		i;
		pte_t	*pte = (pte_t *)(*ptp & ~PGMASK);

		if ((*ptp & ARM_PTP_VALID) == 0) {
			/*
			 * Need to allocate a page table
			 */
			pte = (pte_t *)calloc_ram(__PAGESIZE, __PAGESIZE);
			arm_ptmap((paddr_t)pte, vaddr);
		}
		pte += (vaddr >> 12) & 1023;
		for (i = (vaddr >> 12) & 1023; size && i < 1024; i++) {
			*pte++ = paddr;
			paddr += __PAGESIZE;
			size  -= __PAGESIZE;
		}
	}
	return vaddr + off;
}