original_kernel/arch/mips/ddb5xxx/ddb5477/kgdb_io.c

137 lines
4.5 KiB
C

/*
* kgdb io functions for DDB5477. We use the second serial port (upper one).
*
* Copyright (C) 2001 MontaVista Software Inc.
* Author: jsun@mvista.com or jsun@junsun.net
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
*/
/* ======================= CONFIG ======================== */
/* [jsun] we use the second serial port for kdb */
#define BASE 0xbfa04240
#define MAX_BAUD 115200
/* distance in bytes between two serial registers */
#define REG_OFFSET 8
/*
* 0 - kgdb does serial init
* 1 - kgdb skip serial init
*/
static int remoteDebugInitialized = 0;
/*
* the default baud rate *if* kgdb does serial init
*/
#define BAUD_DEFAULT UART16550_BAUD_38400
/* ======================= END OF CONFIG ======================== */
typedef unsigned char uint8;
typedef unsigned int uint32;
#define UART16550_BAUD_2400 2400
#define UART16550_BAUD_4800 4800
#define UART16550_BAUD_9600 9600
#define UART16550_BAUD_19200 19200
#define UART16550_BAUD_38400 38400
#define UART16550_BAUD_57600 57600
#define UART16550_BAUD_115200 115200
#define UART16550_PARITY_NONE 0
#define UART16550_PARITY_ODD 0x08
#define UART16550_PARITY_EVEN 0x18
#define UART16550_PARITY_MARK 0x28
#define UART16550_PARITY_SPACE 0x38
#define UART16550_DATA_5BIT 0x0
#define UART16550_DATA_6BIT 0x1
#define UART16550_DATA_7BIT 0x2
#define UART16550_DATA_8BIT 0x3
#define UART16550_STOP_1BIT 0x0
#define UART16550_STOP_2BIT 0x4
/* register offset */
#define OFS_RCV_BUFFER 0
#define OFS_TRANS_HOLD 0
#define OFS_SEND_BUFFER 0
#define OFS_INTR_ENABLE (1*REG_OFFSET)
#define OFS_INTR_ID (2*REG_OFFSET)
#define OFS_DATA_FORMAT (3*REG_OFFSET)
#define OFS_LINE_CONTROL (3*REG_OFFSET)
#define OFS_MODEM_CONTROL (4*REG_OFFSET)
#define OFS_RS232_OUTPUT (4*REG_OFFSET)
#define OFS_LINE_STATUS (5*REG_OFFSET)
#define OFS_MODEM_STATUS (6*REG_OFFSET)
#define OFS_RS232_INPUT (6*REG_OFFSET)
#define OFS_SCRATCH_PAD (7*REG_OFFSET)
#define OFS_DIVISOR_LSB (0*REG_OFFSET)
#define OFS_DIVISOR_MSB (1*REG_OFFSET)
/* memory-mapped read/write of the port */
#define UART16550_READ(y) (*((volatile uint8*)(BASE + y)))
#define UART16550_WRITE(y, z) ((*((volatile uint8*)(BASE + y))) = z)
void debugInit(uint32 baud, uint8 data, uint8 parity, uint8 stop)
{
/* disable interrupts */
UART16550_WRITE(OFS_INTR_ENABLE, 0);
/* set up baud rate */
{
uint32 divisor;
/* set DIAB bit */
UART16550_WRITE(OFS_LINE_CONTROL, 0x80);
/* set divisor */
divisor = MAX_BAUD / baud;
UART16550_WRITE(OFS_DIVISOR_LSB, divisor & 0xff);
UART16550_WRITE(OFS_DIVISOR_MSB, (divisor & 0xff00) >> 8);
/* clear DIAB bit */
UART16550_WRITE(OFS_LINE_CONTROL, 0x0);
}
/* set data format */
UART16550_WRITE(OFS_DATA_FORMAT, data | parity | stop);
}
uint8 getDebugChar(void)
{
if (!remoteDebugInitialized) {
remoteDebugInitialized = 1;
debugInit(BAUD_DEFAULT,
UART16550_DATA_8BIT,
UART16550_PARITY_NONE, UART16550_STOP_1BIT);
}
while ((UART16550_READ(OFS_LINE_STATUS) & 0x1) == 0);
return UART16550_READ(OFS_RCV_BUFFER);
}
int putDebugChar(uint8 byte)
{
if (!remoteDebugInitialized) {
remoteDebugInitialized = 1;
debugInit(BAUD_DEFAULT,
UART16550_DATA_8BIT,
UART16550_PARITY_NONE, UART16550_STOP_1BIT);
}
while ((UART16550_READ(OFS_LINE_STATUS) & 0x20) == 0);
UART16550_WRITE(OFS_SEND_BUFFER, byte);
return 1;
}