linux/arch/mn10300/kernel/gdb-io-ttysm.c
David Howells 2f2a2132ff Separate out the proc- and unit-specific header directories from the general
MN10300 arch headers and place them instead in the same directories as contain
the .c files for the processor and unit implementations.

This permits the symlinks include/asm/proc and include/asm/unit to be
dispensed with.  This does, however, require that #include <asm/proc/xxx.h> be
converted to #include <proc/xxx.h> and similarly for asm/unit -> unit.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-04-10 14:33:48 +01:00

302 lines
6.8 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, GxICR_LEVEL_0);
set_intr_level(gdbstub_port->tx_irq, GxICR_LEVEL_0);
set_intr_stub(EXCEP_IRQ_LEVEL0, 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 */
asm volatile(
" and %0,epsw \n"
" or %1,epsw \n"
:
: "i"(~EPSW_IM), "i"(EPSW_IE|EPSW_IM_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;
*_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
watchdog_alert_counter = 0;
#endif /* CONFIG_MN10300_WD_TIMER */
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;
}