#include <Base.h>
#include <Library/BaseLib.h>
#include <Library/FdtSerialPortAddressLib.h>
#include <Library/IoLib.h>
#include <Library/PcdLib.h>
#include <Library/SerialPortLib.h>

Macros
#define	PCI_BRIDGE_32_BIT_IO_SPACE 0x01

#define	R_UART_RXBUF 0

#define	R_UART_TXBUF 0

#define	R_UART_BAUD_LOW 0

#define	R_UART_BAUD_HIGH 1

#define	R_UART_IER 1

#define	R_UART_FCR 2

#define	B_UART_FCR_FIFOE BIT0

#define	B_UART_FCR_FIFO64 BIT5

#define	R_UART_LCR 3

#define	B_UART_LCR_DLAB BIT7

#define	R_UART_MCR 4

#define	B_UART_MCR_DTRC BIT0

#define	B_UART_MCR_RTS BIT1

#define	R_UART_LSR 5

#define	B_UART_LSR_RXRDY BIT0

#define	B_UART_LSR_TXRDY BIT5

#define	B_UART_LSR_TEMT BIT6

#define	R_UART_MSR 6

#define	B_UART_MSR_CTS BIT4

#define	B_UART_MSR_DSR BIT5

#define	B_UART_MSR_RI BIT6

#define	B_UART_MSR_DCD BIT7

Functions
STATIC UINT8	SerialPortReadRegister (UINTN Base, UINTN Offset)

STATIC UINT8	SerialPortWriteRegister (UINTN Base, UINTN Offset, UINT8 Value)

STATIC UINTN	GetSerialRegisterBase (VOID)

STATIC BOOLEAN	SerialPortWritable (UINTN SerialRegisterBase)

RETURN_STATUS EFIAPI	SerialPortInitialize (VOID)

UINTN EFIAPI	SerialPortWrite (IN UINT8 *Buffer, IN UINTN NumberOfBytes)

UINTN EFIAPI	SerialPortRead (OUT UINT8 *Buffer, IN UINTN NumberOfBytes)

BOOLEAN EFIAPI	SerialPortPoll (VOID)

RETURN_STATUS EFIAPI	SerialPortSetControl (IN UINT32 Control)

RETURN_STATUS EFIAPI	SerialPortGetControl (OUT UINT32 *Control)

RETURN_STATUS EFIAPI	SerialPortSetAttributes (IN OUT UINT64 BaudRate, IN OUT UINT32 ReceiveFifoDepth, IN OUT UINT32 Timeout, IN OUT EFI_PARITY_TYPE Parity, IN OUT UINT8 DataBits, IN OUT EFI_STOP_BITS_TYPE StopBits)

Detailed Description

16550 UART Serial Port library functions

SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file EarlyFdtSerialPortLib16550.c.

Macro Definition Documentation

◆ B_UART_FCR_FIFO64

#define B_UART_FCR_FIFO64 BIT5

Definition at line 32 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_FCR_FIFOE

#define B_UART_FCR_FIFOE BIT0

Definition at line 31 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_LCR_DLAB

#define B_UART_LCR_DLAB BIT7

Definition at line 34 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_LSR_RXRDY

#define B_UART_LSR_RXRDY BIT0

Definition at line 39 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_LSR_TEMT

#define B_UART_LSR_TEMT BIT6

Definition at line 41 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_LSR_TXRDY

#define B_UART_LSR_TXRDY BIT5

Definition at line 40 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_MCR_DTRC

#define B_UART_MCR_DTRC BIT0

Definition at line 36 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_MCR_RTS

#define B_UART_MCR_RTS BIT1

Definition at line 37 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_MSR_CTS

#define B_UART_MSR_CTS BIT4

Definition at line 43 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_MSR_DCD

#define B_UART_MSR_DCD BIT7

Definition at line 46 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_MSR_DSR

#define B_UART_MSR_DSR BIT5

Definition at line 44 of file EarlyFdtSerialPortLib16550.c.

◆ B_UART_MSR_RI

#define B_UART_MSR_RI BIT6

Definition at line 45 of file EarlyFdtSerialPortLib16550.c.

◆ PCI_BRIDGE_32_BIT_IO_SPACE

#define PCI_BRIDGE_32_BIT_IO_SPACE 0x01

Definition at line 20 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_BAUD_HIGH

#define R_UART_BAUD_HIGH 1

Definition at line 28 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_BAUD_LOW

#define R_UART_BAUD_LOW 0

Definition at line 27 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_FCR

#define R_UART_FCR 2

Definition at line 30 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_IER

#define R_UART_IER 1

Definition at line 29 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_LCR

#define R_UART_LCR 3

Definition at line 33 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_LSR

#define R_UART_LSR 5

Definition at line 38 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_MCR

#define R_UART_MCR 4

Definition at line 35 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_MSR

#define R_UART_MSR 6

Definition at line 42 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_RXBUF

#define R_UART_RXBUF 0

Definition at line 25 of file EarlyFdtSerialPortLib16550.c.

◆ R_UART_TXBUF

#define R_UART_TXBUF 0

Definition at line 26 of file EarlyFdtSerialPortLib16550.c.

Function Documentation

◆ GetSerialRegisterBase()

STATIC UINTN GetSerialRegisterBase ( VOID )

Retrieve the I/O or MMIO base address register for the PCI UART device.

This function assumes Root Bus Numer is Zero, and enables I/O and MMIO in PCI UART Device if they are not already enabled.

Returns: The base address register of the UART device.

Definition at line 120 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortGetControl()

RETURN_STATUS EFIAPI SerialPortGetControl ( OUT UINT32 * Control )

Retrieve the status of the control bits on a serial device.

Parameters

Control A pointer to return the current control signals from the serial device.

Return values

RETURN_SUCCESS	The control bits were read from the serial device.
RETURN_UNSUPPORTED	The serial device does not support this operation.
RETURN_DEVICE_ERROR	The serial device is not functioning correctly.

Definition at line 558 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortInitialize()

RETURN_STATUS EFIAPI SerialPortInitialize ( VOID )

Initialize the serial device hardware.

If no initialization is required, then return RETURN_SUCCESS. If the serial device was successfully initialized, then return RETURN_SUCCESS. If the serial device could not be initialized, then return RETURN_DEVICE_ERROR.

Return values

RETURN_SUCCESS	The serial device was initialized.
RETURN_DEVICE_ERROR	The serial device could not be initialized.

Definition at line 198 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortPoll()

BOOLEAN EFIAPI SerialPortPoll ( VOID )

Polls a serial device to see if there is any data waiting to be read.

Polls aserial device to see if there is any data waiting to be read. If there is data waiting to be read from the serial device, then TRUE is returned. If there is no data waiting to be read from the serial device, then FALSE is returned.

Return values

TRUE	Data is waiting to be read from the serial device.
FALSE	There is no data waiting to be read from the serial device.

Definition at line 458 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortRead()

UINTN EFIAPI SerialPortRead	(	OUT UINT8 *	Buffer,
		IN UINTN	NumberOfBytes
	)

Reads data from a serial device into a buffer.

Parameters

Buffer	Pointer to the data buffer to store the data read from the serial device.
NumberOfBytes	Number of bytes to read from the serial device.

Return values

0	NumberOfBytes is 0.
>0	The number of bytes read from the serial device. If this value is less than NumberOfBytes, then the read operation failed.

Definition at line 397 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortReadRegister()

STATIC UINT8 SerialPortReadRegister	(	UINTN	Base,
		UINTN	Offset
	)

Read an 8-bit 16550 register. If PcdSerialUseMmio is TRUE, then the value is read from MMIO space. If PcdSerialUseMmio is FALSE, then the value is read from I/O space. The parameter Offset is added to the base address of the 16550 registers that is specified by PcdSerialRegisterBase. PcdSerialRegisterAccessWidth specifies the MMIO space access width and defaults to 8 bit access, and supports 8 or 32 bit access.

Parameters

Base	The base address register of UART device.
Offset	The offset of the 16550 register to read.

Returns: The value read from the 16550 register.

Definition at line 62 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortSetAttributes()

RETURN_STATUS EFIAPI SerialPortSetAttributes	(	IN OUT UINT64 *	BaudRate,
		IN OUT UINT32 *	ReceiveFifoDepth,
		IN OUT UINT32 *	Timeout,
		IN OUT EFI_PARITY_TYPE *	Parity,
		IN OUT UINT8 *	DataBits,
		IN OUT EFI_STOP_BITS_TYPE *	StopBits
	)

Sets the baud rate, receive FIFO depth, transmit/receice time out, parity, data bits, and stop bits on a serial device.

Parameters

BaudRate	The requested baud rate. A BaudRate value of 0 will use the device's default interface speed. On output, the value actually set.
ReveiveFifoDepth	The requested depth of the FIFO on the receive side of the serial interface. A ReceiveFifoDepth value of 0 will use the device's default FIFO depth. On output, the value actually set.
Timeout	The requested time out for a single character in microseconds. This timeout applies to both the transmit and receive side of the interface. A Timeout value of 0 will use the device's default time out value. On output, the value actually set.
Parity	The type of parity to use on this serial device. A Parity value of DefaultParity will use the device's default parity value. On output, the value actually set.
DataBits	The number of data bits to use on the serial device. A DataBits vaule of 0 will use the device's default data bit setting. On output, the value actually set.
StopBits	The number of stop bits to use on this serial device. A StopBits value of DefaultStopBits will use the device's default number of stop bits. On output, the value actually set.

Return values

RETURN_SUCCESS	The new attributes were set on the serial device.
RETURN_UNSUPPORTED	The serial device does not support this operation.
RETURN_INVALID_PARAMETER	One or more of the attributes has an unsupported value.
RETURN_DEVICE_ERROR	The serial device is not functioning correctly.

Definition at line 662 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortSetControl()

RETURN_STATUS EFIAPI SerialPortSetControl ( IN UINT32 Control )

Sets the control bits on a serial device.

Parameters

Control Sets the bits of Control that are settable.

Return values

RETURN_SUCCESS	The new control bits were set on the serial device.
RETURN_UNSUPPORTED	The serial device does not support this operation.
RETURN_DEVICE_ERROR	The serial device is not functioning correctly.

Definition at line 504 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortWritable()

STATIC BOOLEAN SerialPortWritable ( UINTN SerialRegisterBase )

Return whether the hardware flow control signal allows writing.

Parameters

SerialRegisterBase The base address register of UART device.

Return values

TRUE	The serial port is writable.
FALSE	The serial port is not writable.

Definition at line 147 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortWrite()

UINTN EFIAPI SerialPortWrite	(	IN UINT8 *	Buffer,
		IN UINTN	NumberOfBytes
	)

Write data from buffer to serial device.

Writes NumberOfBytes data bytes from Buffer to the serial device. The number of bytes actually written to the serial device is returned. If the return value is less than NumberOfBytes, then the write operation failed.

If Buffer is NULL, then ASSERT().

If NumberOfBytes is zero, then return 0.

Parameters

Buffer	Pointer to the data buffer to be written.
NumberOfBytes	Number of bytes to written to the serial device.

Return values

0	NumberOfBytes is 0.
>0	The number of bytes written to the serial device. If this value is less than NumberOfBytes, then the write operation failed.

Definition at line 305 of file EarlyFdtSerialPortLib16550.c.

◆ SerialPortWriteRegister()

STATIC UINT8 SerialPortWriteRegister	(	UINTN	Base,
		UINTN	Offset,
		UINT8	Value
	)

Write an 8-bit 16550 register. If PcdSerialUseMmio is TRUE, then the value is written to MMIO space. If PcdSerialUseMmio is FALSE, then the value is written to I/O space. The parameter Offset is added to the base address of the 16550 registers that is specified by PcdSerialRegisterBase. PcdSerialRegisterAccessWidth specifies the MMIO space access width and defaults to 8 bit access, and supports 8 or 32 bit access.

Parameters

Base	The base address register of UART device.
Offset	The offset of the 16550 register to write.
Value	The value to write to the 16550 register specified by Offset.

Returns: The value written to the 16550 register.

Definition at line 93 of file EarlyFdtSerialPortLib16550.c.

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ B_UART_FCR_FIFO64

◆ B_UART_FCR_FIFOE

◆ B_UART_LCR_DLAB

◆ B_UART_LSR_RXRDY

◆ B_UART_LSR_TEMT

◆ B_UART_LSR_TXRDY

◆ B_UART_MCR_DTRC

◆ B_UART_MCR_RTS

◆ B_UART_MSR_CTS

◆ B_UART_MSR_DCD

◆ B_UART_MSR_DSR

◆ B_UART_MSR_RI

◆ PCI_BRIDGE_32_BIT_IO_SPACE

◆ R_UART_BAUD_HIGH

◆ R_UART_BAUD_LOW

◆ R_UART_FCR

◆ R_UART_IER

◆ R_UART_LCR

◆ R_UART_LSR

◆ R_UART_MCR

◆ R_UART_MSR

◆ R_UART_RXBUF

◆ R_UART_TXBUF

Function Documentation

◆ GetSerialRegisterBase()

◆ SerialPortGetControl()

◆ SerialPortInitialize()

◆ SerialPortPoll()

◆ SerialPortRead()

◆ SerialPortReadRegister()

◆ SerialPortSetAttributes()

◆ SerialPortSetControl()

◆ SerialPortWritable()

◆ SerialPortWrite()

◆ SerialPortWriteRegister()