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Ignore whitespace Rev 2467 → Rev 2468

/trunk/boot/arch/arm32/loader/mm.c
1,94 → 1,95
/*
* Copyright (c) 2007 Pavel Jancik, Michal Kebrt
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
 
 
/** @addtogroup arm32boot
* @{
*/
/** @file
* @brief Memory management used while booting the kernel.
*/
 
 
#include "mm.h"
 
 
/** Initializes "section" page table entry.
*
* Will be readable/writable by kernel with no access from user mode.
* Will belong to domain 0. No cache or buffering is enabled.
*
* @param pte Section entry to initialize.
* @param frame First frame in the section (frame number).
*
* @note If frame is not 1MB aligned, first lower 1MB aligned frame will be used.
*/
static void init_pte_level0_section(pte_level0_section_t* pte, unsigned int frame)
{
pte->descriptor_type = PTE_DESCRIPTOR_SECTION;
pte->bufferable = 0;
pte->cacheable = 0;
pte->impl_specific = 0;
pte->domain = 0;
pte->should_be_zero_1 = 0;
pte->access_permission = PTE_AP_USER_NO_KERNEL_RW;
pte->should_be_zero_2 = 0;
pte->section_base_addr = frame;
}
 
 
/** Initializes page table used while booting the kernel. */
static void init_page_table(void)
{
int i;
const unsigned int first_kernel_page = ADDR2PFN(PA2KA(0));
 
// create 1:1 virtual-physical mapping (in lower 2GB)
for (i = 0; i < first_kernel_page; i++) {
init_pte_level0_section(&page_table[i], i);
}
 
// create 1:1 virtual-physical mapping in kernel space (upper 2GB),
// physical addresses start from 0
for (i = first_kernel_page; i < PTL0_ENTRIES; i++) {
init_pte_level0_section(&page_table[i], i - first_kernel_page);
}
}
 
 
/** Starts the MMU - initializes page table and enables paging. */
void mmu_start() {
init_page_table();
set_ptl0_address(page_table);
enable_paging();
}
 
 
/** @}
*/
/*
* Copyright (c) 2007 Pavel Jancik, Michal Kebrt
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
 
 
/** @addtogroup arm32boot
* @{
*/
/** @file
* @brief Memory management used while booting the kernel.
*/
 
 
#include "mm.h"
 
 
/** Initializes "section" page table entry.
*
* Will be readable/writable by kernel with no access from user mode.
* Will belong to domain 0. No cache or buffering is enabled.
*
* @param pte Section entry to initialize.
* @param frame First frame in the section (frame number).
*
* @note If frame is not 1MB aligned, first lower 1MB aligned frame will be
* used.
*/
static void init_pte_level0_section(pte_level0_section_t* pte,
unsigned int frame)
{
pte->descriptor_type = PTE_DESCRIPTOR_SECTION;
pte->bufferable = 0;
pte->cacheable = 0;
pte->impl_specific = 0;
pte->domain = 0;
pte->should_be_zero_1 = 0;
pte->access_permission = PTE_AP_USER_NO_KERNEL_RW;
pte->should_be_zero_2 = 0;
pte->section_base_addr = frame;
}
 
/** Initializes page table used while booting the kernel. */
static void init_page_table(void)
{
int i;
const unsigned int first_kernel_page = ADDR2PFN(PA2KA(0));
 
/* Create 1:1 virtual-physical mapping (in lower 2GB). */
for (i = 0; i < first_kernel_page; i++) {
init_pte_level0_section(&page_table[i], i);
}
 
/*
* Create 1:1 virtual-physical mapping in kernel space (upper 2GB),
* physical addresses start from 0.
*/
for (i = first_kernel_page; i < PTL0_ENTRIES; i++) {
init_pte_level0_section(&page_table[i], i - first_kernel_page);
}
}
 
/** Starts the MMU - initializes page table and enables paging. */
void mmu_start() {
init_page_table();
set_ptl0_address(page_table);
enable_paging();
}
 
/** @}
*/