kernel-ark/arch/mn10300/kernel/gdb-io-serial.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

158 lines
3.3 KiB
C

/* 16550 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/nmi.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/gdb-stub.h>
#include <asm/exceptions.h>
#include <asm/serial-regs.h>
#include <unit/serial.h>
/*
* initialise the GDB stub
*/
void gdbstub_io_init(void)
{
u16 tmp;
/* set up the serial port */
GDBPORT_SERIAL_LCR = UART_LCR_WLEN8; /* 1N8 */
GDBPORT_SERIAL_FCR = (UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR |
UART_FCR_CLEAR_XMIT);
FLOWCTL_CLEAR(DTR);
FLOWCTL_SET(RTS);
gdbstub_io_set_baud(115200);
/* we want to get serial receive interrupts */
XIRQxICR(GDBPORT_SERIAL_IRQ) = 0;
tmp = XIRQxICR(GDBPORT_SERIAL_IRQ);
IVAR0 = EXCEP_IRQ_LEVEL0;
set_intr_stub(EXCEP_IRQ_LEVEL0, gdbstub_io_rx_handler);
XIRQxICR(GDBPORT_SERIAL_IRQ) &= ~GxICR_REQUEST;
XIRQxICR(GDBPORT_SERIAL_IRQ) = GxICR_ENABLE | GxICR_LEVEL_0;
tmp = XIRQxICR(GDBPORT_SERIAL_IRQ);
GDBPORT_SERIAL_IER = UART_IER_RDI | UART_IER_RLSI;
/* permit level 0 IRQs to take place */
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)
{
unsigned value;
u8 lcr;
value = 18432000 / 16 / baud;
lcr = GDBPORT_SERIAL_LCR;
GDBPORT_SERIAL_LCR |= UART_LCR_DLAB;
GDBPORT_SERIAL_DLL = value & 0xff;
GDBPORT_SERIAL_DLM = (value >> 8) & 0xff;
GDBPORT_SERIAL_LCR = lcr;
}
/*
* 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 & 0x00000fff;
if (st & UART_LSR_BI) {
gdbstub_proto("### GDB Rx Break Detected ###\n");
return -EINTR;
} else if (st & (UART_LSR_FE | UART_LSR_OE | UART_LSR_PE)) {
gdbstub_proto("### GDB Rx Error (st=%02x) ###\n", st);
return -EIO;
} else {
gdbstub_proto("### 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)
{
FLOWCTL_SET(DTR);
LSR_WAIT_FOR(THRE);
/* FLOWCTL_WAIT_FOR(CTS); */
if (ch == 0x0a) {
GDBPORT_SERIAL_TX = 0x0d;
LSR_WAIT_FOR(THRE);
/* FLOWCTL_WAIT_FOR(CTS); */
}
GDBPORT_SERIAL_TX = ch;
FLOWCTL_CLEAR(DTR);
}
/*
* send a character to the debugger
*/
void gdbstub_io_tx_flush(void)
{
LSR_WAIT_FOR(TEMT);
LSR_WAIT_FOR(THRE);
FLOWCTL_CLEAR(DTR);
}