genode/repos/base/include/spec/x86/bios_data_area.h
2025-01-30 16:30:13 +01:00

59 lines
1.2 KiB
C++

/*
* \brief Structure of the Bios Data Area after preparation through Bender
* \author Martin Stein
* \date 2015-07-10
*/
/*
* Copyright (C) 2015-2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
#ifndef _INCLUDE__SPEC__X86__BIOS_DATA_AREA_H_
#define _INCLUDE__SPEC__X86__BIOS_DATA_AREA_H_
/* Genode includes */
#include <util/mmio.h>
namespace Genode { class Bios_data_area; }
class Genode::Bios_data_area : Mmio<0x12>
{
private:
struct Serial_base_com1 : Register<0x0, 16> { };
struct Equipment : Register<0x10, 16>
{
struct Serial_count : Bitfield<9, 3> { };
};
static addr_t _mmio_base_virt();
Bios_data_area() : Mmio({(char *)(_mmio_base_virt() + 0x400), Mmio::SIZE}) { }
public:
/**
* Obtain I/O ports of COM interfaces from BDA
*/
uint16_t serial_port() const
{
Equipment::access_t count = read<Equipment::Serial_count>();
return count ? read<Serial_base_com1>() : 0;
}
/**
* Return BDA singleton
*/
static Bios_data_area * singleton()
{
static Bios_data_area bda { };
return &bda;
}
};
#endif /* _INCLUDE__SPEC__X86__BIOS_DATA_AREA_H_ */