source: mainline/kernel/genarch/src/mm/as_pt.c@ 901b302

ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 901b302 was 84176f3, checked in by Jakub Jermář <jakub@…>, 6 years ago

arm64: Add support for the architecture

This changeset adds basic support to run HelenOS on AArch64, targeting
the QEMU virt platform.

Boot:

  • Boot relies on the EDK II firmware, GRUB2 for EFI and the HelenOS bootloader (UEFI application). EDK II loads GRUB2 from a CD, GRUB2 loads the HelenOS bootloader (via UEFI) which loads OS components.
  • UEFI applications use the PE/COFF format and must be relocatable. The first problem is solved by manually having the PE/COFF headers and tables written in assembler. The relocatable requirement is addressed by compiling the code with -fpic and having the bootloader relocate itself at its startup.

Kernel:

  • Kernel code for AArch64 consists mostly of stubbing out various architecture-specific hooks: virtual memory management, interrupt and exception handling, context switching (including FPU lazy switching), support for virtual timer, atomic sequences and barriers, cache and TLB maintenance, thread and process initialization.
  • The patch adds a kernel driver for GICv2 (interrupt controller).
  • The PL011 kernel driver is extended to allow userspace to take ownership of the console.
  • The current code is not able to dynamically obtain information about available devices on the underlying machine. The port instead implements a machine-func interface similar to the one implemented by arm32. It defines a machine for the QEMU AArch64 virt platform. The configuration (device addresses and IRQ numbers) is then baked into the machine definition.

User space:

  • Uspace code for AArch64 similarly mostly implements architecture-specific hooks: context saving/restoring, syscall support, TLS support.

The patchset allows to boot the system but user interaction with the OS
is not yet possible.

  • Property mode set to 100644
File size: 4.2 KB
RevLine 
[ef67bab]1/*
[df4ed85]2 * Copyright (c) 2006 Jakub Jermar
[ef67bab]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
[6404aca]29/** @addtogroup kernel_genarch_mm
[b45c443]30 * @{
31 */
32
[0f27b4c]33/**
[b45c443]34 * @file
[da1bafb]35 * @brief Address space functions for 4-level hierarchical pagetables.
[0f27b4c]36 */
37
[ef67bab]38#include <genarch/mm/page_pt.h>
39#include <mm/page.h>
40#include <mm/frame.h>
41#include <mm/as.h>
[1068f6a]42#include <synch/mutex.h>
[ef67bab]43#include <arch/mm/page.h>
44#include <arch/mm/as.h>
[d99c1d2]45#include <typedefs.h>
[44a7ee5]46#include <mem.h>
[ef67bab]47#include <arch.h>
48
[da1bafb]49static pte_t *ptl0_create(unsigned int);
50static void ptl0_destroy(pte_t *);
[ef67bab]51
[da1bafb]52static void pt_lock(as_t *, bool);
53static void pt_unlock(as_t *, bool);
[ada559c]54static bool pt_locked(as_t *);
[2299914]55
[ef67bab]56as_operations_t as_pt_operations = {
[2299914]57 .page_table_create = ptl0_create,
[482826d]58 .page_table_destroy = ptl0_destroy,
[2299914]59 .page_table_lock = pt_lock,
[ada559c]60 .page_table_unlock = pt_unlock,
61 .page_table_locked = pt_locked,
[ef67bab]62};
63
64/** Create PTL0.
65 *
66 * PTL0 of 4-level page table will be created for each address space.
67 *
68 * @param flags Flags can specify whether ptl0 is for the kernel address space.
69 *
70 * @return New PTL0.
[da1bafb]71 *
[ef67bab]72 */
[da1bafb]73pte_t *ptl0_create(unsigned int flags)
[ef67bab]74{
[b0c2075]75 pte_t *dst_ptl0 = (pte_t *)
[f18d01b6]76 PA2KA(frame_alloc(PTL0_FRAMES, FRAME_LOWMEM, PTL0_SIZE - 1));
[a35b458]77
[84176f3]78 memsetb(dst_ptl0, PTL0_SIZE, 0);
79
80 if (!KERNEL_SEPARATE_PTL0 && !(flags & FLAG_AS_KERNEL)) {
[ef67bab]81 /*
82 * Copy the kernel address space portion to new PTL0.
83 */
[a35b458]84
[da1bafb]85 mutex_lock(&AS_KERNEL->lock);
[a35b458]86
[da1bafb]87 pte_t *src_ptl0 =
88 (pte_t *) PA2KA((uintptr_t) AS_KERNEL->genarch.page_table);
[a35b458]89
[6b326ea1]90 uintptr_t src = (uintptr_t)
91 &src_ptl0[PTL0_INDEX(KERNEL_ADDRESS_SPACE_START)];
92 uintptr_t dst = (uintptr_t)
93 &dst_ptl0[PTL0_INDEX(KERNEL_ADDRESS_SPACE_START)];
[a35b458]94
[da1bafb]95 memcpy((void *) dst, (void *) src,
[f18d01b6]96 PTL0_SIZE - (src - (uintptr_t) src_ptl0));
[a35b458]97
[1068f6a]98 mutex_unlock(&AS_KERNEL->lock);
[ef67bab]99 }
[a35b458]100
[7f1c620]101 return (pte_t *) KA2PA((uintptr_t) dst_ptl0);
[ef67bab]102}
[2299914]103
[482826d]104/** Destroy page table.
105 *
106 * Destroy PTL0, other levels are expected to be already deallocated.
107 *
108 * @param page_table Physical address of PTL0.
[da1bafb]109 *
[482826d]110 */
111void ptl0_destroy(pte_t *page_table)
112{
[5df1963]113 frame_free((uintptr_t) page_table, PTL0_FRAMES);
[482826d]114}
115
[2299914]116/** Lock page tables.
117 *
118 * Lock only the address space.
119 * Interrupts must be disabled.
120 *
[da1bafb]121 * @param as Address space.
[2299914]122 * @param lock If false, do not attempt to lock the address space.
[da1bafb]123 *
[2299914]124 */
125void pt_lock(as_t *as, bool lock)
126{
127 if (lock)
[1068f6a]128 mutex_lock(&as->lock);
[2299914]129}
130
131/** Unlock page tables.
132 *
133 * Unlock the address space.
134 * Interrupts must be disabled.
135 *
[da1bafb]136 * @param as Address space.
[2299914]137 * @param unlock If false, do not attempt to unlock the address space.
[da1bafb]138 *
[2299914]139 */
140void pt_unlock(as_t *as, bool unlock)
141{
142 if (unlock)
[1068f6a]143 mutex_unlock(&as->lock);
[2299914]144}
[b45c443]145
[ada559c]146/** Test whether page tables are locked.
147 *
148 * @param as Address space where the page tables belong.
149 *
150 * @return True if the page tables belonging to the address soace
151 * are locked, otherwise false.
152 */
153bool pt_locked(as_t *as)
154{
155 return mutex_locked(&as->lock);
156}
157
[f47fd19]158/** @}
[b45c443]159 */
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