###############################################################################
#
# 16550 serial Rx interrupt handler 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/sys.h>
#include <linux/linkage.h>
#include <asm/smp.h>
#include <asm/cpu-regs.h>
#include <asm/thread_info.h>
#include <asm/frame.inc>
#include <asm/intctl-regs.h>
#include <unit/serial.h>
.text
###############################################################################
#
# GDB stub serial receive interrupt entry point
# - intended to run at interrupt priority 0
#
###############################################################################
.globl gdbstub_io_rx_handler
.type gdbstub_io_rx_handler,@function
gdbstub_io_rx_handler:
movm [d2,d3,a2,a3],(sp)
#if 1
movbu (GDBPORT_SERIAL_IIR),d2
#endif
mov (gdbstub_rx_inp),a3
gdbstub_io_rx_more:
mov a3,a2
add 2,a3
and 0x00000fff,a3
mov (gdbstub_rx_outp),d3
cmp a3,d3
beq gdbstub_io_rx_overflow
movbu (GDBPORT_SERIAL_LSR),d3
btst UART_LSR_DR,d3
beq gdbstub_io_rx_done
movbu (GDBPORT_SERIAL_RX),d2
movbu d3,(gdbstub_rx_buffer+1,a2)
movbu d2,(gdbstub_rx_buffer,a2)
mov a3,(gdbstub_rx_inp)
bra gdbstub_io_rx_more
gdbstub_io_rx_done:
mov GxICR_DETECT,d2
movbu d2,(XIRQxICR(GDBPORT_SERIAL_IRQ)) # ACK the interrupt
movhu (XIRQxICR(GDBPORT_SERIAL_IRQ)),d2 # flush
movm (sp),[d2,d3,a2,a3]
bset 0x01,(gdbstub_busy)
beq gdbstub_io_rx_enter
rti
gdbstub_io_rx_overflow:
bset 0x01,(gdbstub_rx_overflow)
bra gdbstub_io_rx_done
gdbstub_io_rx_enter:
or EPSW_IE|EPSW_IM_1,epsw
add -4,sp
SAVE_ALL
mov 0xffffffff,d0
mov d0,(REG_ORIG_D0,fp)
mov 0x280,d1
mov fp,d0
call gdbstub_rx_irq[],0 # gdbstub_rx_irq(regs,excep)
and ~EPSW_IE,epsw
bclr 0x01,(gdbstub_busy)
.globl gdbstub_return
gdbstub_return:
RESTORE_ALL
.size gdbstub_io_rx_handler,.-gdbstub_io_rx_handler
