1006 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			1006 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
/****************************************************************************
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		THIS SOFTWARE IS NOT COPYRIGHTED
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   HP offers the following for use in the public domain.  HP makes no
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   warranty with regard to the software or it's performance and the
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   user accepts the software "AS IS" with all faults.
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   HP DISCLAIMS ANY WARRANTIES, EXPRESS OR IMPLIED, WITH REGARD
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   TO THIS SOFTWARE INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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****************************************************************************/
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/****************************************************************************
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 *  Header: remcom.c,v 1.34 91/03/09 12:29:49 glenne Exp $
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 *
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 *  Module name: remcom.c $
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 *  Revision: 1.34 $
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 *  Date: 91/03/09 12:29:49 $
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 *  Contributor:     Lake Stevens Instrument Division$
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 *
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 *  Description:     low level support for gdb debugger. $
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 *
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 *  Considerations:  only works on target hardware $
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 *
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 *  Written by:      Glenn Engel $
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 *  ModuleState:     Experimental $
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 *
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 *  NOTES:           See Below $
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 *
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 *  Modified for SPARC by Stu Grossman, Cygnus Support.
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 *  Based on sparc-stub.c, it's modified for SPARClite Debug Unit hardware
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 *  breakpoint support to create sparclite-stub.c, by Kung Hsu, Cygnus Support.
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 *
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 *  This code has been extensively tested on the Fujitsu SPARClite demo board.
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 *
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 *  To enable debugger support, two things need to happen.  One, a
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 *  call to set_debug_traps() is necessary in order to allow any breakpoints
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 *  or error conditions to be properly intercepted and reported to gdb.
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 *  Two, a breakpoint needs to be generated to begin communication.  This
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 *  is most easily accomplished by a call to breakpoint().  Breakpoint()
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 *  simulates a breakpoint by executing a trap #1.
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 *
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 *************
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 *
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 *    The following gdb commands are supported:
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 *
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 * command          function                               Return value
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 *
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 *    g             return the value of the CPU registers  hex data or ENN
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 *    G             set the value of the CPU registers     OK or ENN
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 *
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 *    mAA..AA,LLLL  Read LLLL bytes at address AA..AA      hex data or ENN
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 *    MAA..AA,LLLL: Write LLLL bytes at address AA.AA      OK or ENN
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 *
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 *    c             Resume at current address              SNN   ( signal NN)
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 *    cAA..AA       Continue at address AA..AA             SNN
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 *
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 *    s             Step one instruction                   SNN
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 *    sAA..AA       Step one instruction from AA..AA       SNN
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 *
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 *    k             kill
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 *
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 *    ?             What was the last sigval ?             SNN   (signal NN)
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 *
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 *    bBB..BB	    Set baud rate to BB..BB		   OK or BNN, then sets
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 *							   baud rate
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 *
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 * All commands and responses are sent with a packet which includes a
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 * checksum.  A packet consists of
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 *
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 * $<packet info>#<checksum>.
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 *
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 * where
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 * <packet info> :: <characters representing the command or response>
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 * <checksum>    :: < two hex digits computed as modulo 256 sum of <packetinfo>>
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 *
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 * When a packet is received, it is first acknowledged with either '+' or '-'.
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 * '+' indicates a successful transfer.  '-' indicates a failed transfer.
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 *
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 * Example:
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 *
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 * Host:                  Reply:
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 * $m0,10#2a               +$00010203040506070809101112131415#42
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 *
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 ****************************************************************************/
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#include <string.h>
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#include <signal.h>
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#include "asm.h"
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/************************************************************************
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 *
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 * external low-level support routines
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 */
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extern putDebugChar();   /* write a single character      */
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extern getDebugChar();   /* read and return a single char */
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/* Pointer to hook for outbyte, set by stub's exception handler.  */
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extern void (*__outbyte_hook)();
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/************************************************************************/
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/* BUFMAX defines the maximum number of characters in inbound/outbound buffers*/
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/* at least NUMREGBYTES*2 are needed for register packets */
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#define BUFMAX 2048
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static int initialized = 0;	/* !0 means we've been initialized */
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extern void breakinst();
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static void hw_breakpoint();
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static void set_mem_fault_trap();
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static void get_in_break_mode();
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static const char hexchars[]="0123456789abcdef";
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#define NUMREGS 80 
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/* Number of bytes of registers.  */
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#define NUMREGBYTES (NUMREGS * 4)
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enum regnames {G0, G1, G2, G3, G4, G5, G6, G7,
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		 O0, O1, O2, O3, O4, O5, SP, O7,
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		 L0, L1, L2, L3, L4, L5, L6, L7,
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		 I0, I1, I2, I3, I4, I5, FP, I7,
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		 F0, F1, F2, F3, F4, F5, F6, F7,
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		 F8, F9, F10, F11, F12, F13, F14, F15,
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		 F16, F17, F18, F19, F20, F21, F22, F23,
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		 F24, F25, F26, F27, F28, F29, F30, F31,
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		 Y, PSR, WIM, TBR, PC, NPC, FPSR, CPSR,
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		 DIA1, DIA2, DDA1, DDA2, DDV1, DDV2, DCR, DSR };
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/***************************  ASSEMBLY CODE MACROS *************************/
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/* 									   */
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extern void trap_low();
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asm("
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	.reserve trapstack, 1000 * 4, \"bss\", 8
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	.data
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	.align	4
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in_trap_handler:
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	.word	0
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	.text
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	.align 4
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! This function is called when any SPARC trap (except window overflow or
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! underflow) occurs.  It makes sure that the invalid register window is still
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! available before jumping into C code.  It will also restore the world if you
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! return from handle_exception.
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	.globl " STRINGSYM(trap_low) "
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" STRINGSYM(trap_low) ":
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	mov	%psr, %l0
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	mov	%wim, %l3
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	srl	%l3, %l0, %l4		! wim >> cwp
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	cmp	%l4, 1
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	bne	window_fine		! Branch if not in the invalid window
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	nop
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! Handle window overflow
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	mov	%g1, %l4		! Save g1, we use it to hold the wim
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	srl	%l3, 1, %g1		! Rotate wim right
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	tst	%g1
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	bg	good_wim		! Branch if new wim is non-zero
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	nop
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! At this point, we need to bring a 1 into the high order bit of the wim.
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! Since we don't want to make any assumptions about the number of register
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! windows, we figure it out dynamically so as to setup the wim correctly.
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	not	%g1			! Fill g1 with ones
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	mov	%g1, %wim		! Fill the wim with ones
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	nop
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	nop
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	nop
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	mov	%wim, %g1		! Read back the wim
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	inc	%g1			! Now g1 has 1 just to left of wim
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	srl	%g1, 1, %g1		! Now put 1 at top of wim
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	mov	%g0, %wim		! Clear wim so that subsequent save
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	nop				!  won't trap
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	nop
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	nop
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good_wim:
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	save	%g0, %g0, %g0		! Slip into next window
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	mov	%g1, %wim		! Install the new wim
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	std	%l0, [%sp + 0 * 4]	! save L & I registers
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	std	%l2, [%sp + 2 * 4]
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	std	%l4, [%sp + 4 * 4]
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	std	%l6, [%sp + 6 * 4]
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	std	%i0, [%sp + 8 * 4]
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	std	%i2, [%sp + 10 * 4]
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	std	%i4, [%sp + 12 * 4]
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	std	%i6, [%sp + 14 * 4]
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	restore				! Go back to trap window.
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	mov	%l4, %g1		! Restore %g1
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window_fine:
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	sethi	%hi(in_trap_handler), %l4
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	ld	[%lo(in_trap_handler) + %l4], %l5
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	tst	%l5
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	bg	recursive_trap
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	inc	%l5
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	set	trapstack+1000*4, %sp	! Switch to trap stack
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recursive_trap:
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	st	%l5, [%lo(in_trap_handler) + %l4]
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	sub	%sp,(16+1+6+1+80)*4,%sp	! Make room for input & locals
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 					! + hidden arg + arg spill
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					! + doubleword alignment
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					! + registers[72] local var
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	std	%g0, [%sp + (24 + 0) * 4] ! registers[Gx]
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	std	%g2, [%sp + (24 + 2) * 4]
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	std	%g4, [%sp + (24 + 4) * 4]
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	std	%g6, [%sp + (24 + 6) * 4]
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	std	%i0, [%sp + (24 + 8) * 4] ! registers[Ox]
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	std	%i2, [%sp + (24 + 10) * 4]
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	std	%i4, [%sp + (24 + 12) * 4]
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	std	%i6, [%sp + (24 + 14) * 4]
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					! F0->F31 not implemented
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	mov	%y, %l4
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	mov	%tbr, %l5
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	st	%l4, [%sp + (24 + 64) * 4] ! Y
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	st	%l0, [%sp + (24 + 65) * 4] ! PSR
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	st	%l3, [%sp + (24 + 66) * 4] ! WIM
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	st	%l5, [%sp + (24 + 67) * 4] ! TBR
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	st	%l1, [%sp + (24 + 68) * 4] ! PC
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	st	%l2, [%sp + (24 + 69) * 4] ! NPC
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					! CPSR and FPSR not impl
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	or	%l0, 0xf20, %l4
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	mov	%l4, %psr		! Turn on traps, disable interrupts
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	nop
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	nop
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	nop
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 	call 	" STRINGSYM(get_in_break_mode) "
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 	nop
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	nop
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	nop
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	sethi	%hi(0xff00), %l5
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	or	%l5, %lo(0xff00), %l5
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	lda	[%l5]0x1, %l4
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	st 	%l4, [%sp + (24 + 72) * 4] ! DIA1, debug instr addr 1
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	add	%l5, 4, %l5
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	lda	[%l5]0x1, %l4
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	st 	%l4, [%sp + (24 + 73) * 4] ! DIA2, debug instr addr 2
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	add	%l5, 4, %l5
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	lda	[%l5]0x1, %l4
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	st 	%l4, [%sp + (24 + 74) * 4] ! DDA1, debug data addr 1
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	add	%l5, 4, %l5
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	lda	[%l5]0x1, %l4
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	st 	%l4, [%sp + (24 + 75) * 4] ! DDA2, debug data addr 2
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	add	%l5, 4, %l5
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	lda	[%l5]0x1, %l4
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	st 	%l4, [%sp + (24 + 76) * 4] ! DDV1, debug data val 1
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	add	%l5, 4, %l5
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	lda	[%l5]0x1, %l4
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	st 	%l4, [%sp + (24 + 77) * 4] ! DDV2, debug data val 2 
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	add	%l5, 4, %l5
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	lda	[%l5]0x1, %l4
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	st 	%l4, [%sp + (24 + 78) * 4] ! DCR, debug control reg 
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	add	%l5, 4, %l5
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	lda	[%l5]0x1, %l4
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	st 	%l4, [%sp + (24 + 79) * 4] ! DSR, debug status reg
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	nop
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        nop
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	or	%l0, 0xf20, %l4
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	mov	%l4, %psr		! Turn on traps, disable interrupts
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	nop
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        nop
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        nop
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	call	" STRINGSYM(handle_exception) "
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	add	%sp, 24 * 4, %o0	! Pass address of registers
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! Reload all of the registers that aren't on the stack
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	ld	[%sp + (24 + 1) * 4], %g1 ! registers[Gx]
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	ldd	[%sp + (24 + 2) * 4], %g2
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	ldd	[%sp + (24 + 4) * 4], %g4
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	ldd	[%sp + (24 + 6) * 4], %g6
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	ldd	[%sp + (24 + 8) * 4], %i0 ! registers[Ox]
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	ldd	[%sp + (24 + 10) * 4], %i2
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	ldd	[%sp + (24 + 12) * 4], %i4
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	ldd	[%sp + (24 + 14) * 4], %i6
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        sethi	%hi(0xff00), %l2
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	or	%l2, %lo(0xff00), %l2
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	ldd 	[%sp + (24 + 72) * 4], %l4 ! DIA1, debug instr addr 1
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	stda	%l4, [%l2]0x1 
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	nop
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	nop
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	nop
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	nop
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	ldd	[%sp + (24 + 74) * 4], %l4 ! DDA1, debug data addr 1
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	add	%l2, 8, %l2
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        stda	%l4, [%l2]0x1 
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	nop
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	nop
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	nop
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	nop
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	ldd	[%sp + (24 + 76) * 4], %l4 ! DDV1, debug data value 1
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	add	%l2, 8, %l2
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	stda	%l4, [%l2]0x1 
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	nop
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	nop
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	nop
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	nop
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	ld	[%sp + (24 + 78) * 4], %l4 ! DCR, debug control reg 
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	ld	[%sp + (24 + 79) * 4], %l5 ! DSR, debug control reg 
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	add	%l2, 8, %l2
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	or	%l4, 0x200, %l4
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	sta	%l4, [%l2]0x1
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	add	%l2, 4, %l2
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	sta	%l5, [%l2]0x1
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	nop
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	nop
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	nop
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	nop
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	ldd	[%sp + (24 + 64) * 4], %l0 ! Y & PSR
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	ldd	[%sp + (24 + 68) * 4], %l2 ! PC & NPC
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	restore				! Ensure that previous window is valid
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	save	%g0, %g0, %g0		!  by causing a window_underflow trap
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	mov	%l0, %y
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	mov	%l1, %psr		! Make sure that traps are disabled
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					! for rett
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	sethi	%hi(in_trap_handler), %l4
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	ld	[%lo(in_trap_handler) + %l4], %l5
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	dec	%l5
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	st	%l5, [%lo(in_trap_handler) + %l4]
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	jmpl	%l2, %g0		! Restore old PC
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	rett	%l3			! Restore old nPC
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");
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/* Convert ch from a hex digit to an int */
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static int
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hex(ch)
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     unsigned char ch;
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{
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  if (ch >= 'a' && ch <= 'f')
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    return ch-'a'+10;
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  if (ch >= '0' && ch <= '9')
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    return ch-'0';
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  if (ch >= 'A' && ch <= 'F')
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    return ch-'A'+10;
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  return -1;
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}
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 | 
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/* scan for the sequence $<data>#<checksum>     */
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 | 
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static void
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getpacket(buffer)
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     char *buffer;
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{
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  unsigned char checksum;
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  unsigned char xmitcsum;
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  int i;
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  int count;
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  unsigned char ch;
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  do
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    {
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      /* wait around for the start character, ignore all other characters */
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      while ((ch = (getDebugChar() & 0x7f)) != '$') ;
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      checksum = 0;
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      xmitcsum = -1;
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      count = 0;
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      /* now, read until a # or end of buffer is found */
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      while (count < BUFMAX)
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	{
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	  ch = getDebugChar() & 0x7f;
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	  if (ch == '#')
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	    break;
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	  checksum = checksum + ch;
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	  buffer[count] = ch;
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	  count = count + 1;
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	}
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      if (count >= BUFMAX)
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	continue;
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      buffer[count] = 0;
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      if (ch == '#')
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	{
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	  xmitcsum = hex(getDebugChar() & 0x7f) << 4;
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	  xmitcsum |= hex(getDebugChar() & 0x7f);
 | 
						|
#if 0
 | 
						|
	  /* Humans shouldn't have to figure out checksums to type to it. */
 | 
						|
	  putDebugChar ('+');
 | 
						|
	  return;
 | 
						|
#endif
 | 
						|
	  if (checksum != xmitcsum)
 | 
						|
	    putDebugChar('-');	/* failed checksum */
 | 
						|
	  else
 | 
						|
	    {
 | 
						|
	      putDebugChar('+'); /* successful transfer */
 | 
						|
	      /* if a sequence char is present, reply the sequence ID */
 | 
						|
	      if (buffer[2] == ':')
 | 
						|
		{
 | 
						|
		  putDebugChar(buffer[0]);
 | 
						|
		  putDebugChar(buffer[1]);
 | 
						|
		  /* remove sequence chars from buffer */
 | 
						|
		  count = strlen(buffer);
 | 
						|
		  for (i=3; i <= count; i++)
 | 
						|
		    buffer[i-3] = buffer[i];
 | 
						|
		}
 | 
						|
	    }
 | 
						|
	}
 | 
						|
    }
 | 
						|
  while (checksum != xmitcsum);
 | 
						|
}
 | 
						|
 | 
						|
/* send the packet in buffer.  */
 | 
						|
 | 
						|
static void
 | 
						|
putpacket(buffer)
 | 
						|
     unsigned char *buffer;
 | 
						|
{
 | 
						|
  unsigned char checksum;
 | 
						|
  int count;
 | 
						|
  unsigned char ch;
 | 
						|
 | 
						|
  /*  $<packet info>#<checksum>. */
 | 
						|
  do
 | 
						|
    {
 | 
						|
      putDebugChar('$');
 | 
						|
      checksum = 0;
 | 
						|
      count = 0;
 | 
						|
 | 
						|
      while (ch = buffer[count])
 | 
						|
	{
 | 
						|
	  if (! putDebugChar(ch))
 | 
						|
	    return;
 | 
						|
	  checksum += ch;
 | 
						|
	  count += 1;
 | 
						|
	}
 | 
						|
 | 
						|
      putDebugChar('#');
 | 
						|
      putDebugChar(hexchars[checksum >> 4]);
 | 
						|
      putDebugChar(hexchars[checksum & 0xf]);
 | 
						|
 | 
						|
    }
 | 
						|
  while ((getDebugChar() & 0x7f) != '+');
 | 
						|
}
 | 
						|
 | 
						|
static char remcomInBuffer[BUFMAX];
 | 
						|
static char remcomOutBuffer[BUFMAX];
 | 
						|
 | 
						|
/* Indicate to caller of mem2hex or hex2mem that there has been an
 | 
						|
   error.  */
 | 
						|
static volatile int mem_err = 0;
 | 
						|
 | 
						|
/* Convert the memory pointed to by mem into hex, placing result in buf.
 | 
						|
 * Return a pointer to the last char put in buf (null), in case of mem fault,
 | 
						|
 * return 0.
 | 
						|
 * If MAY_FAULT is non-zero, then we will handle memory faults by returning
 | 
						|
 * a 0, else treat a fault like any other fault in the stub.
 | 
						|
 */
 | 
						|
 | 
						|
static unsigned char *
 | 
						|
mem2hex(mem, buf, count, may_fault)
 | 
						|
     unsigned char *mem;
 | 
						|
     unsigned char *buf;
 | 
						|
     int count;
 | 
						|
     int may_fault;
 | 
						|
{
 | 
						|
  unsigned char ch;
 | 
						|
 | 
						|
  set_mem_fault_trap(may_fault);
 | 
						|
 | 
						|
  while (count-- > 0)
 | 
						|
    {
 | 
						|
      ch = *mem++;
 | 
						|
      if (mem_err)
 | 
						|
	return 0;
 | 
						|
      *buf++ = hexchars[ch >> 4];
 | 
						|
      *buf++ = hexchars[ch & 0xf];
 | 
						|
    }
 | 
						|
 | 
						|
  *buf = 0;
 | 
						|
 | 
						|
  set_mem_fault_trap(0);
 | 
						|
 | 
						|
  return buf;
 | 
						|
}
 | 
						|
 | 
						|
/* convert the hex array pointed to by buf into binary to be placed in mem
 | 
						|
 * return a pointer to the character AFTER the last byte written */
 | 
						|
 | 
						|
static char *
 | 
						|
hex2mem(buf, mem, count, may_fault)
 | 
						|
     unsigned char *buf;
 | 
						|
     unsigned char *mem;
 | 
						|
     int count;
 | 
						|
     int may_fault;
 | 
						|
{
 | 
						|
  int i;
 | 
						|
  unsigned char ch;
 | 
						|
 | 
						|
  set_mem_fault_trap(may_fault);
 | 
						|
 | 
						|
  for (i=0; i<count; i++)
 | 
						|
    {
 | 
						|
      ch = hex(*buf++) << 4;
 | 
						|
      ch |= hex(*buf++);
 | 
						|
      *mem++ = ch;
 | 
						|
      if (mem_err)
 | 
						|
	return 0;
 | 
						|
    }
 | 
						|
 | 
						|
  set_mem_fault_trap(0);
 | 
						|
 | 
						|
  return mem;
 | 
						|
}
 | 
						|
 | 
						|
/* This table contains the mapping between SPARC hardware trap types, and
 | 
						|
   signals, which are primarily what GDB understands.  It also indicates
 | 
						|
   which hardware traps we need to commandeer when initializing the stub. */
 | 
						|
 | 
						|
static struct hard_trap_info
 | 
						|
{
 | 
						|
  unsigned char tt;		/* Trap type code for SPARClite */
 | 
						|
  unsigned char signo;		/* Signal that we map this trap into */
 | 
						|
} hard_trap_info[] = {
 | 
						|
  {1, SIGSEGV},			/* instruction access error */
 | 
						|
  {2, SIGILL},			/* privileged instruction */
 | 
						|
  {3, SIGILL},			/* illegal instruction */
 | 
						|
  {4, SIGEMT},			/* fp disabled */
 | 
						|
  {36, SIGEMT},			/* cp disabled */
 | 
						|
  {7, SIGBUS},			/* mem address not aligned */
 | 
						|
  {9, SIGSEGV},			/* data access exception */
 | 
						|
  {10, SIGEMT},			/* tag overflow */
 | 
						|
  {128+1, SIGTRAP},		/* ta 1 - normal breakpoint instruction */
 | 
						|
  {255, SIGTRAP},		/* hardware breakpoint */
 | 
						|
  {0, 0}			/* Must be last */
 | 
						|
};
 | 
						|
 | 
						|
/* Set up exception handlers for tracing and breakpoints */
 | 
						|
 | 
						|
void
 | 
						|
set_debug_traps()
 | 
						|
{
 | 
						|
  struct hard_trap_info *ht;
 | 
						|
 | 
						|
  for (ht = hard_trap_info; ht->tt && ht->signo; ht++)
 | 
						|
    exceptionHandler(ht->tt, trap_low);
 | 
						|
 | 
						|
  /* In case GDB is started before us, ack any packets (presumably
 | 
						|
     "$?#xx") sitting there.  */
 | 
						|
 | 
						|
  putDebugChar ('+');
 | 
						|
 | 
						|
  initialized = 1;
 | 
						|
}
 | 
						|
 | 
						|
asm ("
 | 
						|
! Trap handler for memory errors.  This just sets mem_err to be non-zero.  It
 | 
						|
! assumes that %l1 is non-zero.  This should be safe, as it is doubtful that
 | 
						|
! 0 would ever contain code that could mem fault.  This routine will skip
 | 
						|
! past the faulting instruction after setting mem_err.
 | 
						|
 | 
						|
	.text
 | 
						|
	.align 4
 | 
						|
 | 
						|
" STRINGSYM(fltr_set_mem_err) ":
 | 
						|
	sethi %hi(" STRINGSYM(mem_err) "), %l0
 | 
						|
	st %l1, [%l0 + %lo(" STRINGSYM(mem_err) ")]
 | 
						|
	jmpl %l2, %g0
 | 
						|
	rett %l2+4
 | 
						|
");
 | 
						|
 | 
						|
static void
 | 
						|
set_mem_fault_trap(enable)
 | 
						|
     int enable;
 | 
						|
{
 | 
						|
  extern void fltr_set_mem_err();
 | 
						|
  mem_err = 0;
 | 
						|
 | 
						|
  if (enable)
 | 
						|
    exceptionHandler(9, fltr_set_mem_err);
 | 
						|
  else
 | 
						|
    exceptionHandler(9, trap_low);
 | 
						|
}
 | 
						|
 | 
						|
asm ("
 | 
						|
	.text
 | 
						|
	.align 4
 | 
						|
 | 
						|
" STRINGSYM(dummy_hw_breakpoint) ":
 | 
						|
	jmpl %l2, %g0
 | 
						|
	rett %l2+4
 | 
						|
	nop
 | 
						|
	nop
 | 
						|
");
 | 
						|
 | 
						|
static void
 | 
						|
set_hw_breakpoint_trap(enable)
 | 
						|
     int enable;
 | 
						|
{
 | 
						|
  extern void dummy_hw_breakpoint();
 | 
						|
 | 
						|
  if (enable)
 | 
						|
    exceptionHandler(255, dummy_hw_breakpoint);
 | 
						|
  else
 | 
						|
    exceptionHandler(255, trap_low);
 | 
						|
}
 | 
						|
 | 
						|
static void
 | 
						|
get_in_break_mode()
 | 
						|
{
 | 
						|
  set_hw_breakpoint_trap(1);
 | 
						|
 | 
						|
  asm("
 | 
						|
        sethi   %hi(0xff10), %l4
 | 
						|
        or      %l4, %lo(0xff10), %l4
 | 
						|
	sta 	%g0, [%l4]0x1	
 | 
						|
	nop
 | 
						|
	nop
 | 
						|
	nop
 | 
						|
      ");
 | 
						|
 | 
						|
  set_hw_breakpoint_trap(0);
 | 
						|
}
 | 
						|
 | 
						|
/* Convert the SPARC hardware trap type code to a unix signal number. */
 | 
						|
 | 
						|
static int
 | 
						|
computeSignal(tt)
 | 
						|
     int tt;
 | 
						|
{
 | 
						|
  struct hard_trap_info *ht;
 | 
						|
 | 
						|
  for (ht = hard_trap_info; ht->tt && ht->signo; ht++)
 | 
						|
    if (ht->tt == tt)
 | 
						|
      return ht->signo;
 | 
						|
 | 
						|
  return SIGHUP;		/* default for things we don't know about */
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * While we find nice hex chars, build an int.
 | 
						|
 * Return number of chars processed.
 | 
						|
 */
 | 
						|
 | 
						|
static int
 | 
						|
hexToInt(char **ptr, int *intValue)
 | 
						|
{
 | 
						|
  int numChars = 0;
 | 
						|
  int hexValue;
 | 
						|
 | 
						|
  *intValue = 0;
 | 
						|
 | 
						|
  while (**ptr)
 | 
						|
    {
 | 
						|
      hexValue = hex(**ptr);
 | 
						|
      if (hexValue < 0)
 | 
						|
	break;
 | 
						|
 | 
						|
      *intValue = (*intValue << 4) | hexValue;
 | 
						|
      numChars ++;
 | 
						|
 | 
						|
      (*ptr)++;
 | 
						|
    }
 | 
						|
 | 
						|
  return (numChars);
 | 
						|
}
 | 
						|
 | 
						|
/* Replacement for outbyte that sends a packet to GDB containing
 | 
						|
   the character to be output.  */
 | 
						|
 | 
						|
static void
 | 
						|
outbyte_stub (int c)
 | 
						|
{
 | 
						|
  static char buf[4];
 | 
						|
 | 
						|
  buf[0] = 'O';
 | 
						|
  buf[1] = hexchars[(c >> 4) & 0xf];
 | 
						|
  buf[2] = hexchars[c % 16];
 | 
						|
  buf[3] = 0;
 | 
						|
  putpacket (buf);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/*
 | 
						|
 * This function does all command procesing for interfacing to gdb.  It
 | 
						|
 * returns 1 if you should skip the instruction at the trap address, 0
 | 
						|
 * otherwise.
 | 
						|
 */
 | 
						|
 | 
						|
 | 
						|
static void
 | 
						|
handle_exception (registers)
 | 
						|
     unsigned long *registers;
 | 
						|
{
 | 
						|
  int tt;			/* Trap type */
 | 
						|
  int sigval;
 | 
						|
  int addr;
 | 
						|
  int length;
 | 
						|
  char *ptr;
 | 
						|
  unsigned long *sp;
 | 
						|
  unsigned long dsr;
 | 
						|
 | 
						|
/* First, we must force all of the windows to be spilled out */
 | 
						|
 | 
						|
  asm("	save %sp, -64, %sp
 | 
						|
	save %sp, -64, %sp
 | 
						|
	save %sp, -64, %sp
 | 
						|
	save %sp, -64, %sp
 | 
						|
	save %sp, -64, %sp
 | 
						|
	save %sp, -64, %sp
 | 
						|
	save %sp, -64, %sp
 | 
						|
	save %sp, -64, %sp
 | 
						|
	restore
 | 
						|
	restore
 | 
						|
	restore
 | 
						|
	restore
 | 
						|
	restore
 | 
						|
	restore
 | 
						|
	restore
 | 
						|
	restore
 | 
						|
");
 | 
						|
 | 
						|
  if (registers[PC] == (unsigned long)breakinst)
 | 
						|
    {
 | 
						|
      registers[PC] = registers[NPC];
 | 
						|
      registers[NPC] += 4;
 | 
						|
    }
 | 
						|
  sp = (unsigned long *)registers[SP];
 | 
						|
 | 
						|
  dsr = (unsigned long)registers[DSR];
 | 
						|
  if (dsr & 0x3c)
 | 
						|
    {
 | 
						|
      tt = 255;
 | 
						|
    }
 | 
						|
  else
 | 
						|
    {
 | 
						|
      tt = (registers[TBR] >> 4) & 0xff;
 | 
						|
    }
 | 
						|
 | 
						|
  /* reply to host that an exception has occurred */
 | 
						|
  sigval = computeSignal(tt);
 | 
						|
  ptr = remcomOutBuffer;
 | 
						|
 | 
						|
  *ptr++ = 'T';
 | 
						|
  *ptr++ = hexchars[sigval >> 4];
 | 
						|
  *ptr++ = hexchars[sigval & 0xf];
 | 
						|
 | 
						|
  *ptr++ = hexchars[PC >> 4];
 | 
						|
  *ptr++ = hexchars[PC & 0xf];
 | 
						|
  *ptr++ = ':';
 | 
						|
  ptr = mem2hex((char *)®isters[PC], ptr, 4, 0);
 | 
						|
  *ptr++ = ';';
 | 
						|
 | 
						|
  *ptr++ = hexchars[FP >> 4];
 | 
						|
  *ptr++ = hexchars[FP & 0xf];
 | 
						|
  *ptr++ = ':';
 | 
						|
  ptr = mem2hex(sp + 8 + 6, ptr, 4, 0); /* FP */
 | 
						|
  *ptr++ = ';';
 | 
						|
 | 
						|
  *ptr++ = hexchars[SP >> 4];
 | 
						|
  *ptr++ = hexchars[SP & 0xf];
 | 
						|
  *ptr++ = ':';
 | 
						|
  ptr = mem2hex((char *)&sp, ptr, 4, 0);
 | 
						|
  *ptr++ = ';';
 | 
						|
 | 
						|
  *ptr++ = hexchars[NPC >> 4];
 | 
						|
  *ptr++ = hexchars[NPC & 0xf];
 | 
						|
  *ptr++ = ':';
 | 
						|
  ptr = mem2hex((char *)®isters[NPC], ptr, 4, 0);
 | 
						|
  *ptr++ = ';';
 | 
						|
 | 
						|
  *ptr++ = hexchars[O7 >> 4];
 | 
						|
  *ptr++ = hexchars[O7 & 0xf];
 | 
						|
  *ptr++ = ':';
 | 
						|
  ptr = mem2hex((char *)®isters[O7], ptr, 4, 0);
 | 
						|
  *ptr++ = ';';
 | 
						|
 | 
						|
  *ptr++ = 0;
 | 
						|
 | 
						|
  putpacket(remcomOutBuffer);
 | 
						|
 | 
						|
  __outbyte_hook = outbyte_stub;
 | 
						|
 | 
						|
  while (1)
 | 
						|
    {
 | 
						|
      remcomOutBuffer[0] = 0;
 | 
						|
 | 
						|
      getpacket(remcomInBuffer);
 | 
						|
      switch (remcomInBuffer[0])
 | 
						|
	{
 | 
						|
	case '?':
 | 
						|
	  remcomOutBuffer[0] = 'S';
 | 
						|
	  remcomOutBuffer[1] = hexchars[sigval >> 4];
 | 
						|
	  remcomOutBuffer[2] = hexchars[sigval & 0xf];
 | 
						|
	  remcomOutBuffer[3] = 0;
 | 
						|
	  break;
 | 
						|
 | 
						|
	case 'd':
 | 
						|
				/* toggle debug flag */
 | 
						|
	  break;
 | 
						|
 | 
						|
	case 'g':		/* return the value of the CPU registers */
 | 
						|
	  {
 | 
						|
	    ptr = remcomOutBuffer;
 | 
						|
	    ptr = mem2hex((char *)registers, ptr, 16 * 4, 0); /* G & O regs */
 | 
						|
	    ptr = mem2hex(sp + 0, ptr, 16 * 4, 0); /* L & I regs */
 | 
						|
	    memset(ptr, '0', 32 * 8); /* Floating point */
 | 
						|
	    ptr = mem2hex((char *)®isters[Y],
 | 
						|
		    ptr + 32 * 4 * 2,
 | 
						|
		    8 * 4,
 | 
						|
		    0);		/* Y, PSR, WIM, TBR, PC, NPC, FPSR, CPSR */
 | 
						|
	    mem2hex((char *)®isters[DIA1], ptr,
 | 
						|
		8 * 4, 0);    /* DIA1, DIA2, DDA1, DDA2, DDV1, DDV2, DCR, DSR */
 | 
						|
	  }
 | 
						|
	  break;
 | 
						|
 | 
						|
	case 'G':	   /* set the value of the CPU registers - return OK */
 | 
						|
	  {
 | 
						|
	    unsigned long *newsp, psr;
 | 
						|
 | 
						|
	    psr = registers[PSR];
 | 
						|
 | 
						|
	    ptr = &remcomInBuffer[1];
 | 
						|
	    hex2mem(ptr, (char *)registers, 16 * 4, 0); /* G & O regs */
 | 
						|
	    hex2mem(ptr + 16 * 4 * 2, sp + 0, 16 * 4, 0); /* L & I regs */
 | 
						|
	    hex2mem(ptr + 64 * 4 * 2, (char *)®isters[Y],
 | 
						|
		8 * 4, 0);    /* Y, PSR, WIM, TBR, PC, NPC, FPSR, CPSR */
 | 
						|
	    hex2mem(ptr + 72 * 4 * 2, (char *)®isters[DIA1],
 | 
						|
		8 * 4, 0);    /* DIA1, DIA2, DDA1, DDA2, DDV1, DDV2, DCR, DSR */
 | 
						|
 | 
						|
	    /* See if the stack pointer has moved.  If so, then copy the saved
 | 
						|
	       locals and ins to the new location.  This keeps the window
 | 
						|
	       overflow and underflow routines happy.  */
 | 
						|
 | 
						|
	    newsp = (unsigned long *)registers[SP];
 | 
						|
	    if (sp != newsp)
 | 
						|
	      sp = memcpy(newsp, sp, 16 * 4);
 | 
						|
 | 
						|
	    /* Don't allow CWP to be modified. */
 | 
						|
 | 
						|
	    if (psr != registers[PSR])
 | 
						|
	      registers[PSR] = (psr & 0x1f) | (registers[PSR] & ~0x1f);
 | 
						|
 | 
						|
	    strcpy(remcomOutBuffer,"OK");
 | 
						|
	  }
 | 
						|
	  break;
 | 
						|
 | 
						|
	case 'm':	  /* mAA..AA,LLLL  Read LLLL bytes at address AA..AA */
 | 
						|
	  /* Try to read %x,%x.  */
 | 
						|
 | 
						|
	  ptr = &remcomInBuffer[1];
 | 
						|
 | 
						|
	  if (hexToInt(&ptr, &addr)
 | 
						|
	      && *ptr++ == ','
 | 
						|
	      && hexToInt(&ptr, &length))
 | 
						|
	    {
 | 
						|
	      if (mem2hex((char *)addr, remcomOutBuffer, length, 1))
 | 
						|
		break;
 | 
						|
 | 
						|
	      strcpy (remcomOutBuffer, "E03");
 | 
						|
	    }
 | 
						|
	  else
 | 
						|
	    strcpy(remcomOutBuffer,"E01");
 | 
						|
	  break;
 | 
						|
 | 
						|
	case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA.AA return OK */
 | 
						|
	  /* Try to read '%x,%x:'.  */
 | 
						|
 | 
						|
	  ptr = &remcomInBuffer[1];
 | 
						|
 | 
						|
	  if (hexToInt(&ptr, &addr)
 | 
						|
	      && *ptr++ == ','
 | 
						|
	      && hexToInt(&ptr, &length)
 | 
						|
	      && *ptr++ == ':')
 | 
						|
	    {
 | 
						|
	      if (hex2mem(ptr, (char *)addr, length, 1))
 | 
						|
		strcpy(remcomOutBuffer, "OK");
 | 
						|
	      else
 | 
						|
		strcpy(remcomOutBuffer, "E03");
 | 
						|
	    }
 | 
						|
	  else
 | 
						|
	    strcpy(remcomOutBuffer, "E02");
 | 
						|
	  break;
 | 
						|
 | 
						|
	case 'c':    /* cAA..AA    Continue at address AA..AA(optional) */
 | 
						|
	  /* try to read optional parameter, pc unchanged if no parm */
 | 
						|
 | 
						|
	  ptr = &remcomInBuffer[1];
 | 
						|
	  if (hexToInt(&ptr, &addr))
 | 
						|
	    {
 | 
						|
	      registers[PC] = addr;
 | 
						|
	      registers[NPC] = addr + 4;
 | 
						|
	    }
 | 
						|
 | 
						|
/* Need to flush the instruction cache here, as we may have deposited a
 | 
						|
   breakpoint, and the icache probably has no way of knowing that a data ref to
 | 
						|
   some location may have changed something that is in the instruction cache.
 | 
						|
 */
 | 
						|
 | 
						|
	  flush_i_cache();
 | 
						|
	  return;
 | 
						|
 | 
						|
	  /* kill the program */
 | 
						|
	case 'k' :		/* do nothing */
 | 
						|
	  break;
 | 
						|
#if 0
 | 
						|
	case 't':		/* Test feature */
 | 
						|
	  asm (" std %f30,[%sp]");
 | 
						|
	  break;
 | 
						|
#endif
 | 
						|
	case 'r':		/* Reset */
 | 
						|
	  asm ("call 0
 | 
						|
		nop ");
 | 
						|
	  break;
 | 
						|
 | 
						|
#if 0
 | 
						|
Disabled until we can unscrew this properly
 | 
						|
 | 
						|
	case 'b':	  /* bBB...  Set baud rate to BB... */
 | 
						|
	  {
 | 
						|
	    int baudrate;
 | 
						|
	    extern void set_timer_3();
 | 
						|
 | 
						|
	    ptr = &remcomInBuffer[1];
 | 
						|
	    if (!hexToInt(&ptr, &baudrate))
 | 
						|
	      {
 | 
						|
		strcpy(remcomOutBuffer,"B01");
 | 
						|
		break;
 | 
						|
	      }
 | 
						|
 | 
						|
	    /* Convert baud rate to uart clock divider */
 | 
						|
	    switch (baudrate)
 | 
						|
	      {
 | 
						|
	      case 38400:
 | 
						|
		baudrate = 16;
 | 
						|
		break;
 | 
						|
	      case 19200:
 | 
						|
		baudrate = 33;
 | 
						|
		break;
 | 
						|
	      case 9600:
 | 
						|
		baudrate = 65;
 | 
						|
		break;
 | 
						|
	      default:
 | 
						|
		strcpy(remcomOutBuffer,"B02");
 | 
						|
		goto x1;
 | 
						|
	      }
 | 
						|
 | 
						|
	    putpacket("OK");	/* Ack before changing speed */
 | 
						|
	    set_timer_3(baudrate); /* Set it */
 | 
						|
	  }
 | 
						|
x1:	  break;
 | 
						|
#endif
 | 
						|
	}			/* switch */
 | 
						|
 | 
						|
      /* reply to the request */
 | 
						|
      putpacket(remcomOutBuffer);
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
/* This function will generate a breakpoint exception.  It is used at the
 | 
						|
   beginning of a program to sync up with a debugger and can be used
 | 
						|
   otherwise as a quick means to stop program execution and "break" into
 | 
						|
   the debugger. */
 | 
						|
 | 
						|
void
 | 
						|
breakpoint()
 | 
						|
{
 | 
						|
  if (!initialized)
 | 
						|
    return;
 | 
						|
 | 
						|
  asm("	.globl " STRINGSYM(breakinst) "
 | 
						|
 | 
						|
	" STRINGSYM(breakinst) ": ta 1
 | 
						|
      ");
 | 
						|
}
 | 
						|
 | 
						|
static void
 | 
						|
hw_breakpoint()
 | 
						|
{
 | 
						|
  asm("
 | 
						|
      ta 127
 | 
						|
      ");
 | 
						|
}
 |