Rev 2349 | Rev 2409 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2198 | jancik | 1 | /* |
| 2236 | kebrt | 2 | * Copyright (c) 2007 Pavel Jancik, Michal Kebrt |
| 2198 | jancik | 3 | * All rights reserved. |
| 4 | * |
||
| 5 | * Redistribution and use in source and binary forms, with or without |
||
| 6 | * modification, are permitted provided that the following conditions |
||
| 7 | * are met: |
||
| 8 | * |
||
| 9 | * - Redistributions of source code must retain the above copyright |
||
| 10 | * notice, this list of conditions and the following disclaimer. |
||
| 11 | * - Redistributions in binary form must reproduce the above copyright |
||
| 12 | * notice, this list of conditions and the following disclaimer in the |
||
| 13 | * documentation and/or other materials provided with the distribution. |
||
| 14 | * - The name of the author may not be used to endorse or promote products |
||
| 15 | * derived from this software without specific prior written permission. |
||
| 16 | * |
||
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
||
| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||
| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
||
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
||
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
||
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
||
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
| 27 | */ |
||
| 28 | |||
| 2323 | kebrt | 29 | |
| 2236 | kebrt | 30 | /** @addtogroup arm32boot |
| 2198 | jancik | 31 | * @{ |
| 32 | */ |
||
| 2349 | kebrt | 33 | /** @file |
| 34 | * @brief Memory management used while booting the kernel. |
||
| 2198 | jancik | 35 | */ |
| 2236 | kebrt | 36 | |
| 2323 | kebrt | 37 | |
| 2198 | jancik | 38 | #include "mm.h" |
| 39 | |||
| 2254 | kebrt | 40 | |
| 2323 | kebrt | 41 | /** Initializes "section" page table entry. |
| 2236 | kebrt | 42 | * |
| 43 | * Will be readable/writable by kernel with no access from user mode. |
||
| 44 | * Will belong to domain 0. No cache or buffering is enabled. |
||
| 45 | * |
||
| 2323 | kebrt | 46 | * @param pte Section entry to initialize. |
| 47 | * @param frame First frame in the section (frame number). |
||
| 48 | * |
||
| 2353 | kebrt | 49 | * @note If frame is not 1MB aligned, first lower 1MB aligned frame will be used. |
| 2234 | jancik | 50 | */ |
| 2339 | kebrt | 51 | static void init_pte_level0_section(pte_level0_section_t* pte, unsigned int frame) |
| 2254 | kebrt | 52 | { |
| 2234 | jancik | 53 | pte->descriptor_type = PTE_DESCRIPTOR_SECTION; |
| 2254 | kebrt | 54 | pte->bufferable = 0; |
| 2198 | jancik | 55 | pte->cacheable = 0; |
| 2241 | kebrt | 56 | pte->impl_specific = 0; |
| 2198 | jancik | 57 | pte->domain = 0; |
| 58 | pte->should_be_zero_1 = 0; |
||
| 2234 | jancik | 59 | pte->access_permission = PTE_AP_USER_NO_KERNEL_RW; |
| 2198 | jancik | 60 | pte->should_be_zero_2 = 0; |
| 2339 | kebrt | 61 | pte->section_base_addr = frame; |
| 2254 | kebrt | 62 | } |
| 2198 | jancik | 63 | |
| 64 | |||
| 2323 | kebrt | 65 | /** Initializes page table used while booting the kernel. */ |
| 2254 | kebrt | 66 | static void init_page_table(void) |
| 67 | { |
||
| 2198 | jancik | 68 | int i; |
| 2339 | kebrt | 69 | const unsigned int first_kernel_page = ADDR2PFN(PA2KA(0)); |
| 2236 | kebrt | 70 | |
| 2323 | kebrt | 71 | // create 1:1 virtual-physical mapping (in lower 2GB) |
| 2339 | kebrt | 72 | for (i = 0; i < first_kernel_page; i++) { |
| 73 | init_pte_level0_section(&page_table[i], i); |
||
| 2234 | jancik | 74 | } |
| 2198 | jancik | 75 | |
| 2323 | kebrt | 76 | // create 1:1 virtual-physical mapping in kernel space (upper 2GB), |
| 77 | // physical addresses start from 0 |
||
| 2339 | kebrt | 78 | for (i = first_kernel_page; i < PTL0_ENTRIES; i++) { |
| 79 | init_pte_level0_section(&page_table[i], i - first_kernel_page); |
||
| 2234 | jancik | 80 | } |
| 2254 | kebrt | 81 | } |
| 82 | |||
| 83 | |||
| 2323 | kebrt | 84 | /** Starts the MMU - initializes page table and enables paging. |
| 85 | */ |
||
| 2254 | kebrt | 86 | void mmu_start() { |
| 87 | init_page_table(); |
||
| 2236 | kebrt | 88 | set_ptl0_address(page_table); |
| 2254 | kebrt | 89 | enable_paging(); |
| 90 | } |
||
| 2198 | jancik | 91 | |
| 2323 | kebrt | 92 | |
| 2198 | jancik | 93 | /** @} |
| 94 | */ |
||
| 95 |