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Diffstat (limited to 'arch/mn10300/kernel/gdb-io-ttysm-low.S')
-rw-r--r--arch/mn10300/kernel/gdb-io-ttysm-low.S93
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/mn10300/kernel/gdb-io-ttysm-low.S b/arch/mn10300/kernel/gdb-io-ttysm-low.S
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+++ b/arch/mn10300/kernel/gdb-io-ttysm-low.S
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+###############################################################################
+#
+# MN10300 On-chip serial Rx interrupt handler for GDB stub 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/thread_info.h>
+#include <asm/cpu-regs.h>
+#include <asm/frame.inc>
+#include <asm/intctl-regs.h>
+#include <asm/unit/serial.h>
+#include "mn10300-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)
+
+ mov (gdbstub_rx_inp),a3
+gdbstub_io_rx_more:
+ mov a3,a2
+ add 2,a3
+ and PAGE_SIZE_asm-1,a3
+ mov (gdbstub_rx_outp),d3
+ cmp a3,d3
+ beq gdbstub_io_rx_overflow
+
+ movbu (SCgSTR),d3
+ btst SC01STR_RBF,d3
+ beq gdbstub_io_rx_done
+ movbu (SCgRXB),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,(GxICR(SCgRXIRQ)) # ACK the interrupt
+ movhu (GxICR(SCgRXIRQ)),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
+
+###############################################################################
+#
+# debugging interrupt - enter the GDB stub proper
+#
+###############################################################################
+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_io_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