mirror of
https://github.com/RGBCube/serenity
synced 2025-05-16 10:14:57 +00:00
09b1b09c19
If we try to align a number above 0xfffff000 to the next multiple of the page size (4 KiB), it would wrap around to 0. This is most likely never what we want, so let's assert if that happens.
59 lines
2.3 KiB
C++
59 lines
2.3 KiB
C++
/*
|
|
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright notice, this
|
|
* list of conditions and the following disclaimer.
|
|
*
|
|
* 2. 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR CONTRIBUTORS 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.
|
|
*/
|
|
|
|
#include <AK/StringView.h>
|
|
#include <Kernel/Arch/PC/BIOS.h>
|
|
#include <Kernel/VM/MemoryManager.h>
|
|
#include <Kernel/VM/TypedMapping.h>
|
|
|
|
namespace Kernel {
|
|
|
|
MappedROM map_bios()
|
|
{
|
|
MappedROM mapping;
|
|
mapping.size = 128 * KiB;
|
|
mapping.paddr = PhysicalAddress(0xe0000);
|
|
mapping.region = MM.allocate_kernel_region(mapping.paddr, page_round_up(mapping.size), {}, Region::Access::Read);
|
|
return mapping;
|
|
}
|
|
|
|
MappedROM map_ebda()
|
|
{
|
|
auto ebda_segment_ptr = map_typed<u16>(PhysicalAddress(0x40e));
|
|
auto ebda_length_ptr = map_typed<u16>(PhysicalAddress(0x413));
|
|
|
|
PhysicalAddress ebda_paddr(*ebda_segment_ptr << 4);
|
|
size_t ebda_size = *ebda_length_ptr;
|
|
|
|
MappedROM mapping;
|
|
mapping.region = MM.allocate_kernel_region(ebda_paddr.page_base(), page_round_up(ebda_size), {}, Region::Access::Read);
|
|
mapping.offset = ebda_paddr.offset_in_page();
|
|
mapping.size = ebda_size;
|
|
mapping.paddr = ebda_paddr;
|
|
return mapping;
|
|
}
|
|
|
|
}
|