The NS16550 is a commonly available UART device. More...

#include <NS16550.h>

Inheritance diagram for NS16550:

Public Member Functions
	NS16550 (const u32 irq)
	Constructor. More...

virtual FileSystem::Result	initialize ()
	Initializes the UART. More...

virtual FileSystem::Result	interrupt (const Size vector)
	Called when an interrupt has been triggered for this device. More...

virtual FileSystem::Result	read (IOBuffer &buffer, Size &size, const Size offset)
	Read bytes from the device. More...

virtual FileSystem::Result	write (IOBuffer &buffer, Size &size, const Size offset)
	Write bytes to the device. More...

Public Member Functions inherited from SerialDevice
	SerialDevice (const u32 irq)
	Constructor. More...

u32	getIrq () const
	Get interrupt vector. More...

Public Member Functions inherited from Device
	Device (const u32 inode, const FileSystem::FileType type)
	Constructor. More...

virtual	~Device ()
	Destructor. More...

virtual const String &	getIdentifier () const
	Get unique device identifier. More...

Public Member Functions inherited from File
	File (const u32 inode, const FileSystem::FileType type=FileSystem::RegularFile, const UserID uid=ZERO, const GroupID gid=ZERO)
	Constructor function. More...

virtual	~File ()
	Destructor function. More...

u32	getInode () const
	Get inode number. More...

FileSystem::FileType	getType () const
	Retrieve our filetype. More...

virtual FileSystem::Result	status (FileSystem::FileStat &st)
	Retrieve file statistics. More...

virtual bool	canRead () const
	Check if the File has data ready for reading. More...

virtual bool	canWrite () const
	Check if the File can be written to. More...

Private Types
enum	Registers { ReceiveBuffer = 0x00, TransmitHolding = 0x00, DivisorLatchLow = 0x00, DivisorLatchHigh = 0x04, InterruptEnable = 0x04, InterruptIdentity = 0x08, FifoControl = 0x08, LineControl = 0x0C, ModemControl = 0x10, LineStatus = 0x14, ModemStatus = 0x18, Scratch = 0x1C, UartStatus = 0x7C, TransmitFifoLvl = 0x80 }
	Hardware registers. More...

enum	InterruptEnableFlags { ReceiveDataInterrupt = (1 << 0) }

enum	InterruptIdentityFlags { InterruptIdentityFifoEnable = (0x3 << 6) }

enum	FifoControlFlags { FifoControlTrigger1 = (0), FifoControlEnable = (1 << 0) }

enum	LineControlFlags { LineControlDivisorLatch = (1 << 7), LineControl8Bits = (0x3 << 0) }

enum	LineStatusFlags { LineStatusTxEmpty = (1 << 6), LineStatusDataReady = (1 << 0) }

enum	UartStatusFlags { UartStatusReceiveAvailable = (1 << 2), UartStatusTransmitAvailable = (1 << 1), UartStatusBusy = (1 << 0) }

Private Member Functions
void	setDivisorLatch (bool enabled)
	Enable access to the divisor latch registers. More...

Additional Inherited Members
Static Public Member Functions inherited from AbstractFactory< SerialDevice >
static SerialDevice *	create ()
	Abstract function to create an instance of T. More...

Static Public Attributes inherited from SerialDevice
static u32	inodeNumber = 2
	Keeps track of inode number for SerialDevices. More...

Protected Attributes inherited from SerialDevice
const u32	m_irq
	interrupt vector More...

Arch::IO	m_io
	I/O instance. More...

Protected Attributes inherited from Device
String	m_identifier
	Unique identifier for this Device. More...

Protected Attributes inherited from File
const u32	m_inode
	Inode number. More...

const FileSystem::FileType	m_type
	Type of this file. More...

UserID	m_uid
	Owner of the file. More...

GroupID	m_gid
	Group of the file. More...

FileSystem::FileModes	m_access
	Access permissions. More...

Size	m_size
	Size of the file, in bytes. More...

Detailed Description

The NS16550 is a commonly available UART device.

See also: ARM

Definition at line 38 of file NS16550.h.

Member Enumeration Documentation

◆ FifoControlFlags

enum NS16550::FifoControlFlags

private

Enumerator
FifoControlTrigger1
FifoControlEnable

Definition at line 73 of file NS16550.h.

◆ InterruptEnableFlags

enum NS16550::InterruptEnableFlags

private

Enumerator
ReceiveDataInterrupt

Definition at line 63 of file NS16550.h.

◆ InterruptIdentityFlags

enum NS16550::InterruptIdentityFlags

private

Enumerator
InterruptIdentityFifoEnable

Definition at line 68 of file NS16550.h.

◆ LineControlFlags

enum NS16550::LineControlFlags

private

Enumerator
LineControlDivisorLatch
LineControl8Bits

Definition at line 79 of file NS16550.h.

◆ LineStatusFlags

enum NS16550::LineStatusFlags

private

Enumerator
LineStatusTxEmpty
LineStatusDataReady

Definition at line 85 of file NS16550.h.

◆ Registers

enum NS16550::Registers

private

Hardware registers.

Enumerator
ReceiveBuffer
TransmitHolding
DivisorLatchLow
DivisorLatchHigh
InterruptEnable
InterruptIdentity
FifoControl
LineControl
ModemControl
LineStatus
ModemStatus
Scratch
UartStatus
TransmitFifoLvl

Definition at line 45 of file NS16550.h.

◆ UartStatusFlags

enum NS16550::UartStatusFlags

private

Enumerator
UartStatusReceiveAvailable
UartStatusTransmitAvailable
UartStatusBusy

Definition at line 91 of file NS16550.h.

Constructor & Destructor Documentation

◆ NS16550()

NS16550::NS16550 ( const u32 irq )

Constructor.

Definition at line 27 of file NS16550.cpp.

References Device::m_identifier.

Member Function Documentation

◆ initialize()

FileSystem::Result NS16550::initialize ( )

virtual

Initializes the UART.

Returns: Result code

Reimplemented from Device.

Definition at line 33 of file NS16550.cpp.

References Memory::Device, DisableIRQ, DivisorLatchHigh, DivisorLatchLow, EnableIRQ, FifoControl, FifoControlEnable, FifoControlTrigger1, InterruptEnable, FileSystem::IOError, isKernel, LineControl, LineControl8Bits, SerialDevice::m_io, SerialDevice::m_irq, IO::map(), PAGESIZE, ProcessCtl(), Memory::Readable, ReceiveDataInterrupt, SELF, IO::setBase(), setDivisorLatch(), IO::Success, FileSystem::Success, Memory::User, Memory::Writable, and ARMIO::write().

Referenced by kernel_main().

◆ interrupt()

FileSystem::Result NS16550::interrupt ( const Size vector )

virtual

Called when an interrupt has been triggered for this device.

Parameters

vector Vector number of the interrupt.

Returns: Result code

Reimplemented from Device.

Definition at line 78 of file NS16550.cpp.

References InterruptEnable, SerialDevice::m_io, FileSystem::Success, and ARMIO::write().

◆ read()

FileSystem::Result NS16550::read	(	IOBuffer &	buffer,
		Size &	size,
		const Size	offset
	)

virtual

Read bytes from the device.

Parameters

buffer	Input/Output buffer to output bytes to.
size	Maximum number of bytes to read on input. On output, the actual number of bytes read.
offset	Offset inside the file to start reading.

Returns: Result code

Reimplemented from File.

Definition at line 85 of file NS16550.cpp.

References IOBuffer::bufferedWrite(), EnableIRQ, IOBuffer::getCount(), InterruptEnable, isKernel, LineStatus, LineStatusDataReady, SerialDevice::m_io, SerialDevice::m_irq, ProcessCtl(), ARMIO::read(), ReceiveBuffer, ReceiveDataInterrupt, FileSystem::RetryAgain, SELF, FileSystem::Success, and ARMIO::write().

◆ setDivisorLatch()

void NS16550::setDivisorLatch ( bool enabled )

private

Enable access to the divisor latch registers.

Parameters

enabled True to enable, false otherwise

Definition at line 149 of file NS16550.cpp.

References LineControl, LineControlDivisorLatch, SerialDevice::m_io, ARMIO::read(), and ARMIO::write().

Referenced by initialize().

◆ write()

FileSystem::Result NS16550::write	(	IOBuffer &	buffer,
		Size &	size,
		const Size	offset
	)

virtual

Write bytes to the device.

Parameters

buffer	Input/Output buffer to input bytes from.
size	Maximum number of bytes to write on input. On output, the actual number of bytes written.
offset	Offset inside the file to start writing.

Returns: Result code

Reimplemented from File.

Definition at line 120 of file NS16550.cpp.

References LineStatus, LineStatusTxEmpty, SerialDevice::m_io, ARMIO::read(), FileSystem::RetryAgain, FileSystem::Success, TransmitHolding, and ARMIO::write().

The documentation for this class was generated from the following files:

server/serial/NS16550.h
server/serial/NS16550.cpp

Public Member Functions

Private Types

Private Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ FifoControlFlags

◆ InterruptEnableFlags

◆ InterruptIdentityFlags

◆ LineControlFlags

◆ LineStatusFlags

◆ Registers

◆ UartStatusFlags

Constructor & Destructor Documentation

◆ NS16550()

Member Function Documentation

◆ initialize()

◆ interrupt()

◆ read()

◆ setDivisorLatch()

◆ write()