305 lines
6.9 KiB
C
305 lines
6.9 KiB
C
/* MN10300 On-chip serial driver for gdbstub I/O
|
|
*
|
|
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public Licence
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the Licence, or (at your option) any later version.
|
|
*/
|
|
#include <linux/string.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/signal.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/console.h>
|
|
#include <linux/init.h>
|
|
#include <linux/tty.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/system.h>
|
|
#include <asm/gdb-stub.h>
|
|
#include <asm/exceptions.h>
|
|
#include <unit/clock.h>
|
|
#include "mn10300-serial.h"
|
|
|
|
#if defined(CONFIG_GDBSTUB_ON_TTYSM0)
|
|
struct mn10300_serial_port *const gdbstub_port = &mn10300_serial_port_sif0;
|
|
#elif defined(CONFIG_GDBSTUB_ON_TTYSM1)
|
|
struct mn10300_serial_port *const gdbstub_port = &mn10300_serial_port_sif1;
|
|
#else
|
|
struct mn10300_serial_port *const gdbstub_port = &mn10300_serial_port_sif2;
|
|
#endif
|
|
|
|
|
|
/*
|
|
* initialise the GDB stub I/O routines
|
|
*/
|
|
void __init gdbstub_io_init(void)
|
|
{
|
|
uint16_t scxctr;
|
|
int tmp;
|
|
|
|
switch (gdbstub_port->clock_src) {
|
|
case MNSCx_CLOCK_SRC_IOCLK:
|
|
gdbstub_port->ioclk = MN10300_IOCLK;
|
|
break;
|
|
|
|
#ifdef MN10300_IOBCLK
|
|
case MNSCx_CLOCK_SRC_IOBCLK:
|
|
gdbstub_port->ioclk = MN10300_IOBCLK;
|
|
break;
|
|
#endif
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
/* set up the serial port */
|
|
gdbstub_io_set_baud(115200);
|
|
|
|
/* we want to get serial receive interrupts */
|
|
set_intr_level(gdbstub_port->rx_irq,
|
|
NUM2GxICR_LEVEL(CONFIG_GDBSTUB_IRQ_LEVEL));
|
|
set_intr_level(gdbstub_port->tx_irq,
|
|
NUM2GxICR_LEVEL(CONFIG_GDBSTUB_IRQ_LEVEL));
|
|
set_intr_stub(NUM2EXCEP_IRQ_LEVEL(CONFIG_GDBSTUB_IRQ_LEVEL),
|
|
gdbstub_io_rx_handler);
|
|
|
|
*gdbstub_port->rx_icr |= GxICR_ENABLE;
|
|
tmp = *gdbstub_port->rx_icr;
|
|
|
|
/* enable the device */
|
|
scxctr = SC01CTR_CLN_8BIT; /* 1N8 */
|
|
switch (gdbstub_port->div_timer) {
|
|
case MNSCx_DIV_TIMER_16BIT:
|
|
scxctr |= SC0CTR_CK_TM8UFLOW_8; /* == SC1CTR_CK_TM9UFLOW_8
|
|
== SC2CTR_CK_TM10UFLOW_8 */
|
|
break;
|
|
|
|
case MNSCx_DIV_TIMER_8BIT:
|
|
scxctr |= SC0CTR_CK_TM2UFLOW_8;
|
|
break;
|
|
}
|
|
|
|
scxctr |= SC01CTR_TXE | SC01CTR_RXE;
|
|
|
|
*gdbstub_port->_control = scxctr;
|
|
tmp = *gdbstub_port->_control;
|
|
|
|
/* permit level 0 IRQs only */
|
|
arch_local_change_intr_mask_level(
|
|
NUM2EPSW_IM(CONFIG_GDBSTUB_IRQ_LEVEL + 1));
|
|
}
|
|
|
|
/*
|
|
* set up the GDB stub serial port baud rate timers
|
|
*/
|
|
void gdbstub_io_set_baud(unsigned baud)
|
|
{
|
|
const unsigned bits = 10; /* 1 [start] + 8 [data] + 0 [parity] +
|
|
* 1 [stop] */
|
|
unsigned long ioclk = gdbstub_port->ioclk;
|
|
unsigned xdiv, tmp;
|
|
uint16_t tmxbr;
|
|
uint8_t tmxmd;
|
|
|
|
if (!baud) {
|
|
baud = 9600;
|
|
} else if (baud == 134) {
|
|
baud = 269; /* 134 is really 134.5 */
|
|
xdiv = 2;
|
|
}
|
|
|
|
try_alternative:
|
|
xdiv = 1;
|
|
|
|
switch (gdbstub_port->div_timer) {
|
|
case MNSCx_DIV_TIMER_16BIT:
|
|
tmxmd = TM8MD_SRC_IOCLK;
|
|
tmxbr = tmp = (ioclk / (baud * xdiv) + 4) / 8 - 1;
|
|
if (tmp > 0 && tmp <= 65535)
|
|
goto timer_okay;
|
|
|
|
tmxmd = TM8MD_SRC_IOCLK_8;
|
|
tmxbr = tmp = (ioclk / (baud * 8 * xdiv) + 4) / 8 - 1;
|
|
if (tmp > 0 && tmp <= 65535)
|
|
goto timer_okay;
|
|
|
|
tmxmd = TM8MD_SRC_IOCLK_32;
|
|
tmxbr = tmp = (ioclk / (baud * 32 * xdiv) + 4) / 8 - 1;
|
|
if (tmp > 0 && tmp <= 65535)
|
|
goto timer_okay;
|
|
|
|
break;
|
|
|
|
case MNSCx_DIV_TIMER_8BIT:
|
|
tmxmd = TM2MD_SRC_IOCLK;
|
|
tmxbr = tmp = (ioclk / (baud * xdiv) + 4) / 8 - 1;
|
|
if (tmp > 0 && tmp <= 255)
|
|
goto timer_okay;
|
|
|
|
tmxmd = TM2MD_SRC_IOCLK_8;
|
|
tmxbr = tmp = (ioclk / (baud * 8 * xdiv) + 4) / 8 - 1;
|
|
if (tmp > 0 && tmp <= 255)
|
|
goto timer_okay;
|
|
|
|
tmxmd = TM2MD_SRC_IOCLK_32;
|
|
tmxbr = tmp = (ioclk / (baud * 32 * xdiv) + 4) / 8 - 1;
|
|
if (tmp > 0 && tmp <= 255)
|
|
goto timer_okay;
|
|
break;
|
|
}
|
|
|
|
/* as a last resort, if the quotient is zero, default to 9600 bps */
|
|
baud = 9600;
|
|
goto try_alternative;
|
|
|
|
timer_okay:
|
|
gdbstub_port->uart.timeout = (2 * bits * HZ) / baud;
|
|
gdbstub_port->uart.timeout += HZ / 50;
|
|
|
|
/* set the timer to produce the required baud rate */
|
|
switch (gdbstub_port->div_timer) {
|
|
case MNSCx_DIV_TIMER_16BIT:
|
|
*gdbstub_port->_tmxmd = 0;
|
|
*gdbstub_port->_tmxbr = tmxbr;
|
|
*gdbstub_port->_tmxmd = TM8MD_INIT_COUNTER;
|
|
*gdbstub_port->_tmxmd = tmxmd | TM8MD_COUNT_ENABLE;
|
|
break;
|
|
|
|
case MNSCx_DIV_TIMER_8BIT:
|
|
*gdbstub_port->_tmxmd = 0;
|
|
*(volatile u8 *) gdbstub_port->_tmxbr = (u8)tmxbr;
|
|
*gdbstub_port->_tmxmd = TM2MD_INIT_COUNTER;
|
|
*gdbstub_port->_tmxmd = tmxmd | TM2MD_COUNT_ENABLE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* wait for a character to come from the debugger
|
|
*/
|
|
int gdbstub_io_rx_char(unsigned char *_ch, int nonblock)
|
|
{
|
|
unsigned ix;
|
|
u8 ch, st;
|
|
#if defined(CONFIG_MN10300_WD_TIMER)
|
|
int cpu;
|
|
#endif
|
|
|
|
*_ch = 0xff;
|
|
|
|
if (gdbstub_rx_unget) {
|
|
*_ch = gdbstub_rx_unget;
|
|
gdbstub_rx_unget = 0;
|
|
return 0;
|
|
}
|
|
|
|
try_again:
|
|
/* pull chars out of the buffer */
|
|
ix = gdbstub_rx_outp;
|
|
barrier();
|
|
if (ix == gdbstub_rx_inp) {
|
|
if (nonblock)
|
|
return -EAGAIN;
|
|
#ifdef CONFIG_MN10300_WD_TIMER
|
|
for (cpu = 0; cpu < NR_CPUS; cpu++)
|
|
watchdog_alert_counter[cpu] = 0;
|
|
#endif
|
|
goto try_again;
|
|
}
|
|
|
|
ch = gdbstub_rx_buffer[ix++];
|
|
st = gdbstub_rx_buffer[ix++];
|
|
barrier();
|
|
gdbstub_rx_outp = ix & (PAGE_SIZE - 1);
|
|
|
|
st &= SC01STR_RXF | SC01STR_RBF | SC01STR_FEF | SC01STR_PEF |
|
|
SC01STR_OEF;
|
|
|
|
/* deal with what we've got
|
|
* - note that the UART doesn't do BREAK-detection for us
|
|
*/
|
|
if (st & SC01STR_FEF && ch == 0) {
|
|
switch (gdbstub_port->rx_brk) {
|
|
case 0: gdbstub_port->rx_brk = 1; goto try_again;
|
|
case 1: gdbstub_port->rx_brk = 2; goto try_again;
|
|
case 2:
|
|
gdbstub_port->rx_brk = 3;
|
|
gdbstub_proto("### GDB MNSERIAL Rx Break Detected"
|
|
" ###\n");
|
|
return -EINTR;
|
|
default:
|
|
goto try_again;
|
|
}
|
|
} else if (st & SC01STR_FEF) {
|
|
if (gdbstub_port->rx_brk)
|
|
goto try_again;
|
|
|
|
gdbstub_proto("### GDB MNSERIAL Framing Error ###\n");
|
|
return -EIO;
|
|
} else if (st & SC01STR_OEF) {
|
|
if (gdbstub_port->rx_brk)
|
|
goto try_again;
|
|
|
|
gdbstub_proto("### GDB MNSERIAL Overrun Error ###\n");
|
|
return -EIO;
|
|
} else if (st & SC01STR_PEF) {
|
|
if (gdbstub_port->rx_brk)
|
|
goto try_again;
|
|
|
|
gdbstub_proto("### GDB MNSERIAL Parity Error ###\n");
|
|
return -EIO;
|
|
} else {
|
|
/* look for the tail-end char on a break run */
|
|
if (gdbstub_port->rx_brk == 3) {
|
|
switch (ch) {
|
|
case 0xFF:
|
|
case 0xFE:
|
|
case 0xFC:
|
|
case 0xF8:
|
|
case 0xF0:
|
|
case 0xE0:
|
|
case 0xC0:
|
|
case 0x80:
|
|
case 0x00:
|
|
gdbstub_port->rx_brk = 0;
|
|
goto try_again;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
gdbstub_port->rx_brk = 0;
|
|
gdbstub_io("### GDB Rx %02x (st=%02x) ###\n", ch, st);
|
|
*_ch = ch & 0x7f;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* send a character to the debugger
|
|
*/
|
|
void gdbstub_io_tx_char(unsigned char ch)
|
|
{
|
|
while (*gdbstub_port->_status & SC01STR_TBF)
|
|
continue;
|
|
|
|
if (ch == 0x0a) {
|
|
*(u8 *) gdbstub_port->_txb = 0x0d;
|
|
while (*gdbstub_port->_status & SC01STR_TBF)
|
|
continue;
|
|
}
|
|
|
|
*(u8 *) gdbstub_port->_txb = ch;
|
|
}
|
|
|
|
/*
|
|
* flush the transmission buffers
|
|
*/
|
|
void gdbstub_io_tx_flush(void)
|
|
{
|
|
while (*gdbstub_port->_status & (SC01STR_TBF | SC01STR_TXF))
|
|
continue;
|
|
}
|