299 lines
8.3 KiB
C
299 lines
8.3 KiB
C
/**
|
|
* PROJECT: ExectOS
|
|
* COPYRIGHT: See COPYING.md in the top level directory
|
|
* FILE: sdk/xtklib/hl/cport.c
|
|
* DESCRIPTION: Serial (COM) port support
|
|
* DEVELOPERS: Rafal Kupiec <belliash@codingworkshop.eu.org>
|
|
*/
|
|
|
|
#include "xtkmapi.h"
|
|
#include "xtklib.h"
|
|
|
|
|
|
/* I/O port addresses for COM1 - COM8 (valid only for ia32 and amd64) */
|
|
ULONG ComPortAddress[] = {0x000, 0x3F8, 0x2F8, 0x3E8, 0x2E8, 0x5F8, 0x4F8, 0x5E8, 0x4E8};
|
|
|
|
|
|
/**
|
|
* This routine gets a byte from serial port.
|
|
*
|
|
* @param Port
|
|
* Address of port object describing a port settings.
|
|
*
|
|
* @param Byte
|
|
* Address of variable where to store the result.
|
|
*
|
|
* @param Wait
|
|
* Specifies whether to wait for a data or not.
|
|
*
|
|
* @param Poll
|
|
* Indicates whether to only poll, not reading the data.
|
|
*
|
|
* @return This routine returns a status code.
|
|
*
|
|
* @since XT 1.0
|
|
*/
|
|
XTSTATUS
|
|
HlComPortGetByte(IN PCPPORT Port,
|
|
OUT PUCHAR Byte,
|
|
IN BOOLEAN Wait,
|
|
IN BOOLEAN Poll)
|
|
{
|
|
UCHAR Lsr;
|
|
ULONG Retry;
|
|
|
|
/* Make sure the port has been initialized */
|
|
if(Port->Address == 0)
|
|
{
|
|
return STATUS_DEVICE_NOT_READY;
|
|
}
|
|
|
|
/* Retry getting data if allowed to wait */
|
|
Retry = Wait ? COMPORT_WAIT_TIMEOUT : 1;
|
|
while(Retry--)
|
|
{
|
|
/* Get LSR for data ready */
|
|
Lsr = HlComPortReadLsr(Port, COMPORT_LSR_DR);
|
|
if((Lsr & COMPORT_LSR_DR) == COMPORT_LSR_DR)
|
|
{
|
|
/* Check for errors */
|
|
if(Lsr & (COMPORT_LSR_FE | COMPORT_LSR_OE | COMPORT_LSR_PE))
|
|
{
|
|
/* Framing, parity or overrun error occurred */
|
|
*Byte = 0;
|
|
return STATUS_IO_DEVICE_ERROR;
|
|
}
|
|
|
|
/* Check if only polling */
|
|
if(Poll)
|
|
{
|
|
/* Only polling, return success */
|
|
return STATUS_SUCCESS;
|
|
}
|
|
|
|
/* Read the byte from serial port */
|
|
*Byte = HlIoPortInByte(PtrToUshort(Port->Address + (ULONG)COMPORT_REG_RBR));
|
|
|
|
/* Check if in modem control mode */
|
|
if(Port->Flags & COMPORT_FLAG_MC)
|
|
{
|
|
/* Handle Carrier Detected (CD) */
|
|
if((HlIoPortInByte(PtrToShort(Port->Address + (ULONG)COMPORT_REG_MSR)) & COMPORT_MSR_DCD) == 0)
|
|
{
|
|
/* Skip byte if no CD present */
|
|
continue;
|
|
}
|
|
}
|
|
return STATUS_SUCCESS;
|
|
}
|
|
}
|
|
|
|
/* Reset LSR and return that no data found */
|
|
HlComPortReadLsr(Port, 0);
|
|
return STATUS_NOT_FOUND;
|
|
}
|
|
|
|
/**
|
|
* Reads LSR from specified serial port.
|
|
*
|
|
* @param Port
|
|
* Address of COM port.
|
|
*
|
|
* @param Byte
|
|
* Value expected from the port.
|
|
*
|
|
* @return Byte read from COM port.
|
|
*
|
|
* @since XT 1.0
|
|
*/
|
|
UCHAR
|
|
HlComPortReadLsr(IN PCPPORT Port,
|
|
IN UCHAR Byte)
|
|
{
|
|
UCHAR Lsr, Msr;
|
|
STATIC UCHAR RingFlag;
|
|
|
|
/* Read the Line Status Register (LSR) */
|
|
Lsr = HlIoPortInByte(PtrToUshort(Port->Address + (ULONG)COMPORT_REG_LSR));
|
|
|
|
/* Check if expected byte is present */
|
|
if((Lsr & Byte) == 0)
|
|
{
|
|
/* Check Modem Status Register (MSR) for ring indicator */
|
|
Msr = HlIoPortInByte(PtrToUshort(Port->Address + (ULONG)COMPORT_REG_MSR));
|
|
RingFlag |= (Msr & COMPORT_MSR_RI) ? 1 : 2;
|
|
if(RingFlag == 3)
|
|
{
|
|
/* Ring indicator toggled, use modem control */
|
|
Port->Flags |= COMPORT_FLAG_MC;
|
|
}
|
|
}
|
|
|
|
/* Return byte read */
|
|
return Lsr;
|
|
}
|
|
|
|
/**
|
|
* This routine writes a byte to the serial port.
|
|
*
|
|
* @param Port
|
|
* Address of port object describing a port settings.
|
|
*
|
|
* @param Byte
|
|
* Data to be written.
|
|
*
|
|
* @return This routine returns a status code.
|
|
*
|
|
* @since XT 1.0
|
|
*/
|
|
XTSTATUS
|
|
HlComPortPutByte(IN PCPPORT Port,
|
|
IN UCHAR Byte)
|
|
{
|
|
UCHAR Lsr, Msr;
|
|
|
|
/* Make sure the port has been initialized */
|
|
if(Port->Address == 0)
|
|
{
|
|
return STATUS_DEVICE_NOT_READY;
|
|
}
|
|
|
|
/* Check if port is in modem control */
|
|
while(Port->Flags & COMPORT_FLAG_MC)
|
|
{
|
|
/* Get the Modem Status Register (MSR) */
|
|
Msr = HlIoPortInByte(PtrToUshort(Port->Address + (ULONG)COMPORT_REG_MSR)) & COMPORT_MSR_DSRCTSCD;
|
|
if(Msr != COMPORT_MSR_DSRCTSCD)
|
|
{
|
|
/* Take character, if CD is not set */
|
|
Lsr = HlComPortReadLsr(Port, 0);
|
|
if((Msr & COMPORT_MSR_DCD) == 0 && (Lsr & COMPORT_LSR_DR) == COMPORT_LSR_DR)
|
|
{
|
|
/* Eat the character */
|
|
HlIoPortInByte(PtrToUshort(Port->Address + (ULONG)COMPORT_REG_RBR));
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* CD, CTS and DSR are set, we can continue */
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Wait for busy port */
|
|
while((HlComPortReadLsr(Port, COMPORT_LSR_THRE) & COMPORT_LSR_THRE) == 0);
|
|
|
|
/* Send byte to the port */
|
|
HlIoPortOutByte(PtrToUshort(Port->Address + (ULONG)COMPORT_REG_THR), Byte);
|
|
|
|
return STATUS_SUCCESS;
|
|
}
|
|
|
|
/**
|
|
* This routine initializes the COM port.
|
|
*
|
|
* @param Port
|
|
* Address of port object describing a port settings.
|
|
*
|
|
* @param PortNumber
|
|
* Supplies a port number.
|
|
*
|
|
* @param BaudRate
|
|
* Supplies an optional port baud rate.
|
|
*
|
|
* @return This routine returns a status code.
|
|
*
|
|
* @since XT 1.0
|
|
*/
|
|
XTSTATUS
|
|
HlInitializeComPort(IN OUT PCPPORT Port,
|
|
IN ULONG PortNumber,
|
|
IN ULONG BaudRate)
|
|
{
|
|
PUCHAR Address;
|
|
UCHAR Byte = 0;
|
|
ULONG Mode;
|
|
|
|
/* Check if serial port is set */
|
|
if(PortNumber == 0)
|
|
{
|
|
/* Use COM1 by default */
|
|
PortNumber = 1;
|
|
}
|
|
|
|
/* We support only a pre-defined number of ports */
|
|
if(PortNumber > ARRAY_SIZE(ComPortAddress))
|
|
{
|
|
/* Fail if wrong/unsupported port used */
|
|
return STATUS_INVALID_PARAMETER;
|
|
}
|
|
|
|
/* Check if baud rate is set */
|
|
if(BaudRate == 0)
|
|
{
|
|
/* Use default baud (clock) rate if not set */
|
|
BaudRate = COMPORT_CLOCK_RATE;
|
|
Port->Flags = COMPORT_FLAG_DBR;
|
|
}
|
|
|
|
/* Store COM pointer */
|
|
Address = UlongToPtr(ComPortAddress[PortNumber]);
|
|
|
|
/* Check whether this port is not already initialized */
|
|
if((Port->Address == Address) && (Port->Baud == BaudRate))
|
|
{
|
|
return STATUS_SUCCESS;
|
|
}
|
|
|
|
/* Test if chosen COM port exists */
|
|
do
|
|
{
|
|
/* Check whether the 16450/16550 scratch register exists */
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPROT_REG_SR), Byte);
|
|
if(HlIoPortInByte(PtrToUshort(Address + (ULONG)COMPROT_REG_SR)) != Byte)
|
|
{
|
|
return STATUS_NOT_FOUND;
|
|
}
|
|
} while(++Byte != 0);
|
|
|
|
/* Disable interrupts */
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_REG_LCR), COMPORT_LSR_DIS);
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_REG_IER), COMPORT_LSR_DIS);
|
|
|
|
/* Enable Divisor Latch Access Bit (DLAB) */
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_REG_LCR), COMPORT_LCR_DLAB);
|
|
|
|
/* Set baud rate */
|
|
Mode = COMPORT_CLOCK_RATE / BaudRate;
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_DIV_DLL), (UCHAR)(Mode & 0xFF));
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_DIV_DLM), (UCHAR)((Mode >> 8) & 0xFF));
|
|
|
|
/* Set 8 data bits, 1 stop bits, no parity (8n1) */
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_REG_LCR),
|
|
COMPORT_LCR_8DATA | COMPORT_LCR_1STOP | COMPORT_LCR_PARN);
|
|
|
|
/* Enable DTR, RTS and OUT2 */
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_REG_MCR),
|
|
COMPORT_MCR_DTR | COMPORT_MCR_RTS | COMPORT_MCR_OUT2);
|
|
|
|
/* Enable FIFO */
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_REG_FCR),
|
|
COMPORT_FCR_ENABLE | COMPORT_FCR_RCVR_RESET | COMPORT_FCR_TXMT_RESET);
|
|
|
|
/* Enable loopback mode and test serial port */
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_REG_MCR), COMPORT_MCR_LOOP);
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_REG_RBR), COMPORT_MSR_TST);
|
|
if(HlIoPortInByte(PtrToUshort(Address + (ULONG)COMPORT_REG_RBR)) != COMPORT_MSR_TST)
|
|
{
|
|
return STATUS_IO_DEVICE_ERROR;
|
|
}
|
|
|
|
/* Disable loopback mode and use port normally */
|
|
HlIoPortOutByte(PtrToUshort(Address + (ULONG)COMPORT_REG_MCR), COMPORT_MCR_NOM);
|
|
Port->Address = Address;
|
|
Port->Baud = BaudRate;
|
|
|
|
/* Return success */
|
|
return STATUS_SUCCESS;
|
|
}
|