binutils-gdb/gdb/sh-stub.c
1996-05-17 20:41:56 +00:00

1554 lines
39 KiB
C

/* sh-stub.c -- debugging stub for the Hitachi-SH.
NOTE!! This code has to be compiled with optimization, otherwise the
function inlining which generates the exception handlers won't work.
*/
/* This is originally based on an m68k software stub written by Glenn
Engel at HP, but has changed quite a bit.
Modifications for the SH by Ben Lee and Steve Chamberlain
*/
/****************************************************************************
THIS SOFTWARE IS NOT COPYRIGHTED
HP offers the following for use in the public domain. HP makes no
warranty with regard to the software or it's performance and the
user accepts the software "AS IS" with all faults.
HP DISCLAIMS ANY WARRANTIES, EXPRESS OR IMPLIED, WITH REGARD
TO THIS SOFTWARE INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
****************************************************************************/
/* Remote communication protocol.
A debug packet whose contents are <data>
is encapsulated for transmission in the form:
$ <data> # CSUM1 CSUM2
<data> must be ASCII alphanumeric and cannot include characters
'$' or '#'. If <data> starts with two characters followed by
':', then the existing stubs interpret this as a sequence number.
CSUM1 and CSUM2 are ascii hex representation of an 8-bit
checksum of <data>, the most significant nibble is sent first.
the hex digits 0-9,a-f are used.
Receiver responds with:
+ - if CSUM is correct and ready for next packet
- - if CSUM is incorrect
<data> is as follows:
All values are encoded in ascii hex digits.
Request Packet
read registers g
reply XX....X Each byte of register data
is described by two hex digits.
Registers are in the internal order
for GDB, and the bytes in a register
are in the same order the machine uses.
or ENN for an error.
write regs GXX..XX Each byte of register data
is described by two hex digits.
reply OK for success
ENN for an error
write reg Pn...=r... Write register n... with value r...,
which contains two hex digits for each
byte in the register (target byte
order).
reply OK for success
ENN for an error
(not supported by all stubs).
read mem mAA..AA,LLLL AA..AA is address, LLLL is length.
reply XX..XX XX..XX is mem contents
Can be fewer bytes than requested
if able to read only part of the data.
or ENN NN is errno
write mem MAA..AA,LLLL:XX..XX
AA..AA is address,
LLLL is number of bytes,
XX..XX is data
reply OK for success
ENN for an error (this includes the case
where only part of the data was
written).
cont cAA..AA AA..AA is address to resume
If AA..AA is omitted,
resume at same address.
step sAA..AA AA..AA is address to resume
If AA..AA is omitted,
resume at same address.
last signal ? Reply the current reason for stopping.
This is the same reply as is generated
for step or cont : SAA where AA is the
signal number.
There is no immediate reply to step or cont.
The reply comes when the machine stops.
It is SAA AA is the "signal number"
or... TAAn...:r...;n:r...;n...:r...;
AA = signal number
n... = register number
r... = register contents
or... WAA The process exited, and AA is
the exit status. This is only
applicable for certains sorts of
targets.
kill request k
toggle debug d toggle debug flag (see 386 & 68k stubs)
reset r reset -- see sparc stub.
reserved <other> On other requests, the stub should
ignore the request and send an empty
response ($#<checksum>). This way
we can extend the protocol and GDB
can tell whether the stub it is
talking to uses the old or the new.
search tAA:PP,MM Search backwards starting at address
AA for a match with pattern PP and
mask MM. PP and MM are 4 bytes.
Not supported by all stubs.
general query qXXXX Request info about XXXX.
general set QXXXX=yyyy Set value of XXXX to yyyy.
query sect offs qOffsets Get section offsets. Reply is
Text=xxx;Data=yyy;Bss=zzz
console output Otext Send text to stdout. Only comes from
remote target.
Responses can be run-length encoded to save space. A '*' means that
the next character is an ASCII encoding giving a repeat count which
stands for that many repititions of the character preceding the '*'.
The encoding is n+29, yielding a printable character where n >=3
(which is where rle starts to win). Don't use an n > 126.
So
"0* " means the same as "0000". */
#include <string.h>
#include <setjmp.h>
#define COND_BR_MASK 0xff00
#define UCOND_DBR_MASK 0xe000
#define UCOND_RBR_MASK 0xf0df
#define TRAPA_MASK 0xff00
#define COND_DISP 0x00ff
#define UCOND_DISP 0x0fff
#define UCOND_REG 0x0f00
#define BF_INSTR 0x8b00
#define BT_INSTR 0x8900
#define BRA_INSTR 0xa000
#define BSR_INSTR 0xb000
#define JMP_INSTR 0x402b
#define JSR_INSTR 0x400b
#define RTS_INSTR 0x000b
#define RTE_INSTR 0x002b
#define TRAPA_INSTR 0xc300
#define SSTEP_INSTR 0xc3ff
#define T_BIT_MASK 0x0001
/*
* BUFMAX defines the maximum number of characters in inbound/outbound
* buffers at least NUMREGBYTES*2 are needed for register packets
*/
#define BUFMAX 1024
/*
* Number of bytes for registers
*/
#define NUMREGBYTES 112 /* 92 */
/*
* typedef
*/
typedef void (*Function) ();
/*
* Forward declarations
*/
static int hex (char);
static char *mem2hex (char *, char *, int);
static char *hex2mem (char *, char *, int);
static int hexToInt (char **, int *);
static void getpacket (char *);
static void putpacket (char *);
static void handle_buserror (void);
static int computeSignal (int exceptionVector);
static void handle_exception (int exceptionVector);
void init_serial();
int putDebugChar (char);
char getDebugChar (void);
/* These are in the file but in asm statements so the compiler can't see them */
void catch_exception_4 (void);
void catch_exception_6 (void);
void catch_exception_9 (void);
void catch_exception_10 (void);
void catch_exception_11 (void);
void catch_exception_32 (void);
void catch_exception_33 (void);
void catch_exception_255 (void);
#define catch_exception_random catch_exception_255 /* Treat all odd ones like 255 */
void breakpoint (void);
#define init_stack_size 8*1024 /* if you change this you should also modify BINIT */
#define stub_stack_size 8*1024
int init_stack[init_stack_size] __attribute__ ((section ("stack"))) = {0};
int stub_stack[stub_stack_size] __attribute__ ((section ("stack"))) = {0};
typedef struct
{
void (*func_cold) ();
int *stack_cold;
void (*func_warm) ();
int *stack_warm;
void (*(handler[256 - 4])) ();
}
vec_type;
void INIT ();
void BINIT ();
/* When you link take care that this is at address 0 -
or wherever your vbr points */
#define CPU_BUS_ERROR_VEC 9
#define DMA_BUS_ERROR_VEC 10
#define NMI_VEC 11
#define INVALID_INSN_VEC 4
#define INVALID_SLOT_VEC 6
#define TRAP_VEC 32
#define IO_VEC 33
#define USER_VEC 255
#define BCR (*(volatile short *)(0x05FFFFA0)) /* Bus control register */
#define BAS (0x800) /* Byte access select */
#define WCR1 (*(volatile short *)(0x05ffffA2)) /* Wait state control register */
const vec_type vectable =
{
&BINIT, /* 0: Power-on reset PC */
init_stack + init_stack_size, /* 1: Power-on reset SP */
&BINIT, /* 2: Manual reset PC */
init_stack + init_stack_size, /* 3: Manual reset SP */
{
&catch_exception_4, /* 4: General invalid instruction */
&catch_exception_random, /* 5: Reserved for system */
&catch_exception_6, /* 6: Invalid slot instruction */
&catch_exception_random, /* 7: Reserved for system */
&catch_exception_random, /* 8: Reserved for system */
&catch_exception_9, /* 9: CPU bus error */
&catch_exception_10, /* 10: DMA bus error */
&catch_exception_11, /* 11: NMI */
&catch_exception_random, /* 12: User break */
&catch_exception_random, /* 13: Reserved for system */
&catch_exception_random, /* 14: Reserved for system */
&catch_exception_random, /* 15: Reserved for system */
&catch_exception_random, /* 16: Reserved for system */
&catch_exception_random, /* 17: Reserved for system */
&catch_exception_random, /* 18: Reserved for system */
&catch_exception_random, /* 19: Reserved for system */
&catch_exception_random, /* 20: Reserved for system */
&catch_exception_random, /* 21: Reserved for system */
&catch_exception_random, /* 22: Reserved for system */
&catch_exception_random, /* 23: Reserved for system */
&catch_exception_random, /* 24: Reserved for system */
&catch_exception_random, /* 25: Reserved for system */
&catch_exception_random, /* 26: Reserved for system */
&catch_exception_random, /* 27: Reserved for system */
&catch_exception_random, /* 28: Reserved for system */
&catch_exception_random, /* 29: Reserved for system */
&catch_exception_random, /* 30: Reserved for system */
&catch_exception_random, /* 31: Reserved for system */
&catch_exception_32, /* 32: Trap instr (user vectors) */
&catch_exception_33, /* 33: Trap instr (user vectors) */
&catch_exception_random, /* 34: Trap instr (user vectors) */
&catch_exception_random, /* 35: Trap instr (user vectors) */
&catch_exception_random, /* 36: Trap instr (user vectors) */
&catch_exception_random, /* 37: Trap instr (user vectors) */
&catch_exception_random, /* 38: Trap instr (user vectors) */
&catch_exception_random, /* 39: Trap instr (user vectors) */
&catch_exception_random, /* 40: Trap instr (user vectors) */
&catch_exception_random, /* 41: Trap instr (user vectors) */
&catch_exception_random, /* 42: Trap instr (user vectors) */
&catch_exception_random, /* 43: Trap instr (user vectors) */
&catch_exception_random, /* 44: Trap instr (user vectors) */
&catch_exception_random, /* 45: Trap instr (user vectors) */
&catch_exception_random, /* 46: Trap instr (user vectors) */
&catch_exception_random, /* 47: Trap instr (user vectors) */
&catch_exception_random, /* 48: Trap instr (user vectors) */
&catch_exception_random, /* 49: Trap instr (user vectors) */
&catch_exception_random, /* 50: Trap instr (user vectors) */
&catch_exception_random, /* 51: Trap instr (user vectors) */
&catch_exception_random, /* 52: Trap instr (user vectors) */
&catch_exception_random, /* 53: Trap instr (user vectors) */
&catch_exception_random, /* 54: Trap instr (user vectors) */
&catch_exception_random, /* 55: Trap instr (user vectors) */
&catch_exception_random, /* 56: Trap instr (user vectors) */
&catch_exception_random, /* 57: Trap instr (user vectors) */
&catch_exception_random, /* 58: Trap instr (user vectors) */
&catch_exception_random, /* 59: Trap instr (user vectors) */
&catch_exception_random, /* 60: Trap instr (user vectors) */
&catch_exception_random, /* 61: Trap instr (user vectors) */
&catch_exception_random, /* 62: Trap instr (user vectors) */
&catch_exception_random, /* 63: Trap instr (user vectors) */
&catch_exception_random, /* 64: IRQ0 */
&catch_exception_random, /* 65: IRQ1 */
&catch_exception_random, /* 66: IRQ2 */
&catch_exception_random, /* 67: IRQ3 */
&catch_exception_random, /* 68: IRQ4 */
&catch_exception_random, /* 69: IRQ5 */
&catch_exception_random, /* 70: IRQ6 */
&catch_exception_random, /* 71: IRQ7 */
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_random,
&catch_exception_255}};
char in_nmi; /* Set when handling an NMI, so we don't reenter */
int dofault; /* Non zero, bus errors will raise exception */
int *stub_sp;
/* debug > 0 prints ill-formed commands in valid packets & checksum errors */
int remote_debug;
/* jump buffer used for setjmp/longjmp */
jmp_buf remcomEnv;
enum regnames
{
R0, R1, R2, R3, R4, R5, R6, R7,
R8, R9, R10, R11, R12, R13, R14,
R15, PC, PR, GBR, VBR, MACH, MACL, SR,
TICKS, STALLS, CYCLES, INSTS, PLR
};
typedef struct
{
short *memAddr;
short oldInstr;
}
stepData;
int registers[NUMREGBYTES / 4];
stepData instrBuffer;
char stepped;
static const char hexchars[] = "0123456789abcdef";
char remcomInBuffer[BUFMAX];
char remcomOutBuffer[BUFMAX];
char highhex(int x)
{
return hexchars[(x >> 4) & 0xf];
}
char lowhex(int x)
{
return hexchars[x & 0xf];
}
/*
* Assembly macros
*/
#define BREAKPOINT() asm("trapa #0x20"::);
/*
* Routines to handle hex data
*/
static int
hex (char ch)
{
if ((ch >= 'a') && (ch <= 'f'))
return (ch - 'a' + 10);
if ((ch >= '0') && (ch <= '9'))
return (ch - '0');
if ((ch >= 'A') && (ch <= 'F'))
return (ch - 'A' + 10);
return (-1);
}
/* convert the memory, pointed to by mem into hex, placing result in buf */
/* return a pointer to the last char put in buf (null) */
static char *
mem2hex (char *mem, char *buf, int count)
{
int i;
int ch;
for (i = 0; i < count; i++)
{
ch = *mem++;
*buf++ = highhex (ch);
*buf++ = lowhex (ch);
}
*buf = 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 (char *buf, char *mem, int count)
{
int i;
unsigned char ch;
for (i = 0; i < count; i++)
{
ch = hex (*buf++) << 4;
ch = ch + hex (*buf++);
*mem++ = ch;
}
return (mem);
}
/**********************************************/
/* 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)
{
*intValue = (*intValue << 4) | hexValue;
numChars++;
}
else
break;
(*ptr)++;
}
return (numChars);
}
/*
* Routines to get and put packets
*/
/* scan for the sequence $<data>#<checksum> */
static
void
getpacket (char *buffer)
{
unsigned char checksum;
unsigned char xmitcsum;
int i;
int count;
char ch;
do
{
/* wait around for the start character, ignore all other characters */
while ((ch = getDebugChar ()) != '$');
checksum = 0;
xmitcsum = -1;
count = 0;
/* now, read until a # or end of buffer is found */
while (count < BUFMAX)
{
ch = getDebugChar ();
if (ch == '#')
break;
checksum = checksum + ch;
buffer[count] = ch;
count = count + 1;
}
buffer[count] = 0;
if (ch == '#')
{
xmitcsum = hex (getDebugChar ()) << 4;
xmitcsum += hex (getDebugChar ());
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. The host get's one chance to read it.
This routine does not wait for a positive acknowledge. */
static void
putpacket (register char *buffer)
{
register int checksum;
register int count;
/* $<packet info>#<checksum>. */
do
{
char *src = buffer;
putDebugChar ('$');
checksum = 0;
while (*src)
{
int runlen;
/* Do run length encoding */
for (runlen = 0; runlen < 100; runlen ++)
{
if (src[0] != src[runlen])
{
if (runlen > 3)
{
int encode;
/* Got a useful amount */
putDebugChar (*src);
checksum += *src;
putDebugChar ('*');
checksum += '*';
checksum += (encode = runlen + ' ' - 4);
putDebugChar (encode);
src += runlen;
}
else
{
putDebugChar (*src);
checksum += *src;
src++;
}
break;
}
}
}
putDebugChar ('#');
putDebugChar (highhex(checksum));
putDebugChar (lowhex(checksum));
}
while (getDebugChar() != '+');
}
/* a bus error has occurred, perform a longjmp
to return execution and allow handling of the error */
void
handle_buserror (void)
{
longjmp (remcomEnv, 1);
}
/*
* this function takes the SH-1 exception number and attempts to
* translate this number into a unix compatible signal value
*/
static int
computeSignal (int exceptionVector)
{
int sigval;
switch (exceptionVector)
{
case INVALID_INSN_VEC:
sigval = 4;
break;
case INVALID_SLOT_VEC:
sigval = 4;
break;
case CPU_BUS_ERROR_VEC:
sigval = 10;
break;
case DMA_BUS_ERROR_VEC:
sigval = 10;
break;
case NMI_VEC:
sigval = 2;
break;
case TRAP_VEC:
case USER_VEC:
sigval = 5;
break;
default:
sigval = 7; /* "software generated"*/
break;
}
return (sigval);
}
void
doSStep (void)
{
short *instrMem;
int displacement;
int reg;
unsigned short opcode;
instrMem = (short *) registers[PC];
opcode = *instrMem;
stepped = 1;
if ((opcode & COND_BR_MASK) == BT_INSTR)
{
if (registers[SR] & T_BIT_MASK)
{
displacement = (opcode & COND_DISP) << 1;
if (displacement & 0x80)
displacement |= 0xffffff00;
/*
* Remember PC points to second instr.
* after PC of branch ... so add 4
*/
instrMem = (short *) (registers[PC] + displacement + 4);
}
else
instrMem += 1;
}
else if ((opcode & COND_BR_MASK) == BF_INSTR)
{
if (registers[SR] & T_BIT_MASK)
instrMem += 1;
else
{
displacement = (opcode & COND_DISP) << 1;
if (displacement & 0x80)
displacement |= 0xffffff00;
/*
* Remember PC points to second instr.
* after PC of branch ... so add 4
*/
instrMem = (short *) (registers[PC] + displacement + 4);
}
}
else if ((opcode & UCOND_DBR_MASK) == BRA_INSTR)
{
displacement = (opcode & UCOND_DISP) << 1;
if (displacement & 0x0800)
displacement |= 0xfffff000;
/*
* Remember PC points to second instr.
* after PC of branch ... so add 4
*/
instrMem = (short *) (registers[PC] + displacement + 4);
}
else if ((opcode & UCOND_RBR_MASK) == JSR_INSTR)
{
reg = (char) ((opcode & UCOND_REG) >> 8);
instrMem = (short *) registers[reg];
}
else if (opcode == RTS_INSTR)
instrMem = (short *) registers[PR];
else if (opcode == RTE_INSTR)
instrMem = (short *) registers[15];
else if ((opcode & TRAPA_MASK) == TRAPA_INSTR)
instrMem = (short *) ((opcode & ~TRAPA_MASK) << 2);
else
instrMem += 1;
instrBuffer.memAddr = instrMem;
instrBuffer.oldInstr = *instrMem;
*instrMem = SSTEP_INSTR;
}
void
undoSStep (void)
{
/*
If we single stepped,
restore the old instruction!
*/
if (stepped)
{ short *instrMem;
instrMem = instrBuffer.memAddr;
*instrMem = instrBuffer.oldInstr;
}
stepped = 0;
}
/*
This function does all exception handling. It only does two things -
it figures out why it was called and tells gdb, and then it reacts
to gdb's requests.
When in the monitor mode we talk a human on the serial line rather than gdb.
*/
void
gdb_handle_exception (int exceptionVector)
{
int sigval;
int addr, length;
char *ptr;
/* reply to host that an exception has occurred */
sigval = computeSignal (exceptionVector);
remcomOutBuffer[0] = 'S';
remcomOutBuffer[1] = highhex(sigval);
remcomOutBuffer[2] = lowhex (sigval);
remcomOutBuffer[3] = 0;
putpacket (remcomOutBuffer);
/*
* exception 255 indicates a software trap
* inserted in place of code ... so back up
* PC by one instruction, since this instruction
* will later be replaced by its original one!
*/
if (exceptionVector == 0xff
|| exceptionVector == 0x20)
registers[PC] -= 2;
/*
* Do the thangs needed to undo
* any stepping we may have done!
*/
undoSStep ();
while (1)
{
remcomOutBuffer[0] = 0;
getpacket (remcomInBuffer);
switch (remcomInBuffer[0])
{
case '?':
remcomOutBuffer[0] = 'S';
remcomOutBuffer[1] = highhex (sigval);
remcomOutBuffer[2] = lowhex (sigval);
remcomOutBuffer[3] = 0;
break;
case 'd':
remote_debug = !(remote_debug); /* toggle debug flag */
break;
case 'g': /* return the value of the CPU registers */
mem2hex ((char *) registers, remcomOutBuffer, NUMREGBYTES);
break;
case 'G': /* set the value of the CPU registers - return OK */
hex2mem (&remcomInBuffer[1], (char *) registers, NUMREGBYTES);
strcpy (remcomOutBuffer, "OK");
break;
/* mAA..AA,LLLL Read LLLL bytes at address AA..AA */
case 'm':
if (setjmp (remcomEnv) == 0)
{
dofault = 0;
/* TRY, TO READ %x,%x. IF SUCCEED, SET PTR = 0 */
ptr = &remcomInBuffer[1];
if (hexToInt (&ptr, &addr))
if (*(ptr++) == ',')
if (hexToInt (&ptr, &length))
{
ptr = 0;
mem2hex ((char *) addr, remcomOutBuffer, length);
}
if (ptr)
strcpy (remcomOutBuffer, "E01");
}
else
strcpy (remcomOutBuffer, "E03");
/* restore handler for bus error */
dofault = 1;
break;
/* MAA..AA,LLLL: Write LLLL bytes at address AA.AA return OK */
case 'M':
if (setjmp (remcomEnv) == 0)
{
dofault = 0;
/* TRY, TO READ '%x,%x:'. IF SUCCEED, SET PTR = 0 */
ptr = &remcomInBuffer[1];
if (hexToInt (&ptr, &addr))
if (*(ptr++) == ',')
if (hexToInt (&ptr, &length))
if (*(ptr++) == ':')
{
hex2mem (ptr, (char *) addr, length);
ptr = 0;
strcpy (remcomOutBuffer, "OK");
}
if (ptr)
strcpy (remcomOutBuffer, "E02");
}
else
strcpy (remcomOutBuffer, "E03");
/* restore handler for bus error */
dofault = 1;
break;
/* cAA..AA Continue at address AA..AA(optional) */
/* sAA..AA Step one instruction from AA..AA(optional) */
case 'c':
case 's':
{
/* tRY, to read optional parameter, pc unchanged if no parm */
ptr = &remcomInBuffer[1];
if (hexToInt (&ptr, &addr))
registers[PC] = addr;
if (remcomInBuffer[0] == 's')
doSStep ();
}
return;
break;
/* kill the program */
case 'k': /* do nothing */
break;
} /* switch */
/* reply to the request */
putpacket (remcomOutBuffer);
}
}
#define GDBCOOKIE 0x5ac
static int ingdbmode;
/* We've had an exception - choose to go into the monitor or
the gdb stub */
void handle_exception(int exceptionVector)
{
#ifdef MONITOR
if (ingdbmode != GDBCOOKIE)
monitor_handle_exception (exceptionVector);
else
#endif
gdb_handle_exception (exceptionVector);
}
void
gdb_mode()
{
ingdbmode = GDBCOOKIE;
breakpoint();
}
/* 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 (void)
{
BREAKPOINT ();
}
asm ("_BINIT: mov.l L1,r15");
asm ("bra _INIT");
asm ("nop");
asm ("L1: .long _init_stack + 8*1024*4");
void
INIT (void)
{
/* First turn on the ram */
WCR1 = 0; /* Never sample wait */
BCR = BAS; /* use lowbyte/high byte */
init_serial();
#ifdef MONITOR
reset_hook ();
#endif
in_nmi = 0;
dofault = 1;
stepped = 0;
stub_sp = stub_stack + stub_stack_size;
breakpoint ();
while (1)
;
}
static void sr()
{
/* Calling Reset does the same as pressing the button */
asm (".global _Reset
.global _WarmReset
_Reset:
_WarmReset:
mov.l L_sp,r15
bra _INIT
nop
.align 2
L_sp: .long _init_stack + 8000");
asm("saveRegisters:
mov.l @(L_reg, pc), r0
mov.l @r15+, r1 ! pop R0
mov.l r2, @(0x08, r0) ! save R2
mov.l r1, @r0 ! save R0
mov.l @r15+, r1 ! pop R1
mov.l r3, @(0x0c, r0) ! save R3
mov.l r1, @(0x04, r0) ! save R1
mov.l r4, @(0x10, r0) ! save R4
mov.l r5, @(0x14, r0) ! save R5
mov.l r6, @(0x18, r0) ! save R6
mov.l r7, @(0x1c, r0) ! save R7
mov.l r8, @(0x20, r0) ! save R8
mov.l r9, @(0x24, r0) ! save R9
mov.l r10, @(0x28, r0) ! save R10
mov.l r11, @(0x2c, r0) ! save R11
mov.l r12, @(0x30, r0) ! save R12
mov.l r13, @(0x34, r0) ! save R13
mov.l r14, @(0x38, r0) ! save R14
mov.l @r15+, r4 ! save arg to handleException
add #8, r15 ! hide PC/SR values on stack
mov.l r15, @(0x3c, r0) ! save R15
add #-8, r15 ! save still needs old SP value
add #92, r0 ! readjust register pointer
mov r15, r2
add #4, r2
mov.l @r2, r2 ! R2 has SR
mov.l @r15, r1 ! R1 has PC
mov.l r2, @-r0 ! save SR
sts.l macl, @-r0 ! save MACL
sts.l mach, @-r0 ! save MACH
stc.l vbr, @-r0 ! save VBR
stc.l gbr, @-r0 ! save GBR
sts.l pr, @-r0 ! save PR
mov.l @(L_stubstack, pc), r2
mov.l @(L_hdl_except, pc), r3
mov.l @r2, r15
jsr @r3
mov.l r1, @-r0 ! save PC
mov.l @(L_stubstack, pc), r0
mov.l @(L_reg, pc), r1
bra restoreRegisters
mov.l r15, @r0 ! save __stub_stack
.align 2
L_reg:
.long _registers
L_stubstack:
.long _stub_sp
L_hdl_except:
.long _handle_exception");
}
static void rr()
{
asm("
.align 2
.global _resume
_resume:
mov r4,r1
restoreRegisters:
add #8, r1 ! skip to R2
mov.l @r1+, r2 ! restore R2
mov.l @r1+, r3 ! restore R3
mov.l @r1+, r4 ! restore R4
mov.l @r1+, r5 ! restore R5
mov.l @r1+, r6 ! restore R6
mov.l @r1+, r7 ! restore R7
mov.l @r1+, r8 ! restore R8
mov.l @r1+, r9 ! restore R9
mov.l @r1+, r10 ! restore R10
mov.l @r1+, r11 ! restore R11
mov.l @r1+, r12 ! restore R12
mov.l @r1+, r13 ! restore R13
mov.l @r1+, r14 ! restore R14
mov.l @r1+, r15 ! restore programs stack
mov.l @r1+, r0
add #-8, r15 ! uncover PC/SR on stack
mov.l r0, @r15 ! restore PC onto stack
lds.l @r1+, pr ! restore PR
ldc.l @r1+, gbr ! restore GBR
ldc.l @r1+, vbr ! restore VBR
lds.l @r1+, mach ! restore MACH
lds.l @r1+, macl ! restore MACL
mov.l @r1, r0
add #-88, r1 ! readjust reg pointer to R1
mov.l r0, @(4, r15) ! restore SR onto stack+4
mov.l r2, @-r15
mov.l L_in_nmi, r0
mov #0, r2
mov.b r2, @r0
mov.l @r15+, r2
mov.l @r1+, r0 ! restore R0
rte
mov.l @r1, r1 ! restore R1
");
}
static __inline__ void code_for_catch_exception(int n)
{
asm(" .globl _catch_exception_%O0" : : "i" (n) );
asm(" _catch_exception_%O0:" :: "i" (n) );
asm(" add #-4, r15 ! reserve spot on stack ");
asm(" mov.l r1, @-r15 ! push R1 ");
if (n == NMI_VEC)
{
/* Special case for NMI - make sure that they don't nest */
asm(" mov.l r0, @-r15 ! push R0");
asm(" mov.l L_in_nmi, r0");
asm(" tas.b @r0 ! Fend off against addtnl NMIs");
asm(" bt noNMI");
asm(" mov.l @r15+, r0");
asm(" mov.l @r15+, r1");
asm(" add #4, r15");
asm(" rte");
asm(" nop");
asm(".align 2");
asm("L_in_nmi: .long _in_nmi");
asm("noNMI:");
}
else
{
if (n == CPU_BUS_ERROR_VEC)
{
/* Exception 9 (bus errors) are disasbleable - so that you
can probe memory and get zero instead of a fault.
Because the vector table may be in ROM we don't revector
the interrupt like all the other stubs, we check in here
*/
asm("mov.l L_dofault,r1");
asm("mov.l @r1,r1");
asm("tst r1,r1");
asm("bf faultaway");
asm("bsr _handle_buserror");
asm(".align 2");
asm("L_dofault: .long _dofault");
asm("faultaway:");
}
asm(" mov #15<<4, r1 ");
asm(" ldc r1, sr ! disable interrupts ");
asm(" mov.l r0, @-r15 ! push R0 ");
}
/* Prepare for saving context, we've already pushed r0 and r1, stick exception number
into the frame */
asm(" mov r15, r0 ");
asm(" add #8, r0 ");
asm(" mov %0,r1" :: "i" (n) );
asm(" extu.b r1,r1 ");
asm(" bra saveRegisters ! save register values ");
asm(" mov.l r1, @r0 ! save exception # ");
}
static void
exceptions()
{
code_for_catch_exception (CPU_BUS_ERROR_VEC);
code_for_catch_exception (DMA_BUS_ERROR_VEC);
code_for_catch_exception (INVALID_INSN_VEC);
code_for_catch_exception (INVALID_SLOT_VEC);
code_for_catch_exception (NMI_VEC);
code_for_catch_exception (TRAP_VEC);
code_for_catch_exception (USER_VEC);
code_for_catch_exception (IO_VEC);
}
/* Support for Serial I/O using on chip uart */
#define SMR0 (*(volatile char *)(0x05FFFEC0)) /* Channel 0 serial mode register */
#define BRR0 (*(volatile char *)(0x05FFFEC1)) /* Channel 0 bit rate register */
#define SCR0 (*(volatile char *)(0x05FFFEC2)) /* Channel 0 serial control register */
#define TDR0 (*(volatile char *)(0x05FFFEC3)) /* Channel 0 transmit data register */
#define SSR0 (*(volatile char *)(0x05FFFEC4)) /* Channel 0 serial status register */
#define RDR0 (*(volatile char *)(0x05FFFEC5)) /* Channel 0 receive data register */
#define SMR1 (*(volatile char *)(0x05FFFEC8)) /* Channel 1 serial mode register */
#define BRR1 (*(volatile char *)(0x05FFFEC9)) /* Channel 1 bit rate register */
#define SCR1 (*(volatile char *)(0x05FFFECA)) /* Channel 1 serial control register */
#define TDR1 (*(volatile char *)(0x05FFFECB)) /* Channel 1 transmit data register */
#define SSR1 (*(volatile char *)(0x05FFFECC)) /* Channel 1 serial status register */
#define RDR1 (*(volatile char *)(0x05FFFECD)) /* Channel 1 receive data register */
/*
* Serial mode register bits
*/
#define SYNC_MODE 0x80
#define SEVEN_BIT_DATA 0x40
#define PARITY_ON 0x20
#define ODD_PARITY 0x10
#define STOP_BITS_2 0x08
#define ENABLE_MULTIP 0x04
#define PHI_64 0x03
#define PHI_16 0x02
#define PHI_4 0x01
/*
* Serial control register bits
*/
#define SCI_TIE 0x80 /* Transmit interrupt enable */
#define SCI_RIE 0x40 /* Receive interrupt enable */
#define SCI_TE 0x20 /* Transmit enable */
#define SCI_RE 0x10 /* Receive enable */
#define SCI_MPIE 0x08 /* Multiprocessor interrupt enable */
#define SCI_TEIE 0x04 /* Transmit end interrupt enable */
#define SCI_CKE1 0x02 /* Clock enable 1 */
#define SCI_CKE0 0x01 /* Clock enable 0 */
/*
* Serial status register bits
*/
#define SCI_TDRE 0x80 /* Transmit data register empty */
#define SCI_RDRF 0x40 /* Receive data register full */
#define SCI_ORER 0x20 /* Overrun error */
#define SCI_FER 0x10 /* Framing error */
#define SCI_PER 0x08 /* Parity error */
#define SCI_TEND 0x04 /* Transmit end */
#define SCI_MPB 0x02 /* Multiprocessor bit */
#define SCI_MPBT 0x01 /* Multiprocessor bit transfer */
/*
* Port B IO Register (PBIOR)
*/
#define PBIOR (*(volatile char *)(0x05FFFFC6))
#define PB15IOR 0x8000
#define PB14IOR 0x4000
#define PB13IOR 0x2000
#define PB12IOR 0x1000
#define PB11IOR 0x0800
#define PB10IOR 0x0400
#define PB9IOR 0x0200
#define PB8IOR 0x0100
#define PB7IOR 0x0080
#define PB6IOR 0x0040
#define PB5IOR 0x0020
#define PB4IOR 0x0010
#define PB3IOR 0x0008
#define PB2IOR 0x0004
#define PB1IOR 0x0002
#define PB0IOR 0x0001
/*
* Port B Control Register (PBCR1)
*/
#define PBCR1 (*(volatile short *)(0x05FFFFCC))
#define PB15MD1 0x8000
#define PB15MD0 0x4000
#define PB14MD1 0x2000
#define PB14MD0 0x1000
#define PB13MD1 0x0800
#define PB13MD0 0x0400
#define PB12MD1 0x0200
#define PB12MD0 0x0100
#define PB11MD1 0x0080
#define PB11MD0 0x0040
#define PB10MD1 0x0020
#define PB10MD0 0x0010
#define PB9MD1 0x0008
#define PB9MD0 0x0004
#define PB8MD1 0x0002
#define PB8MD0 0x0001
#define PB15MD PB15MD1|PB14MD0
#define PB14MD PB14MD1|PB14MD0
#define PB13MD PB13MD1|PB13MD0
#define PB12MD PB12MD1|PB12MD0
#define PB11MD PB11MD1|PB11MD0
#define PB10MD PB10MD1|PB10MD0
#define PB9MD PB9MD1|PB9MD0
#define PB8MD PB8MD1|PB8MD0
#define PB_TXD1 PB11MD1
#define PB_RXD1 PB10MD1
#define PB_TXD0 PB9MD1
#define PB_RXD0 PB8MD1
/*
* Port B Control Register (PBCR2)
*/
#define PBCR2 0x05FFFFCE
#define PB7MD1 0x8000
#define PB7MD0 0x4000
#define PB6MD1 0x2000
#define PB6MD0 0x1000
#define PB5MD1 0x0800
#define PB5MD0 0x0400
#define PB4MD1 0x0200
#define PB4MD0 0x0100
#define PB3MD1 0x0080
#define PB3MD0 0x0040
#define PB2MD1 0x0020
#define PB2MD0 0x0010
#define PB1MD1 0x0008
#define PB1MD0 0x0004
#define PB0MD1 0x0002
#define PB0MD0 0x0001
#define PB7MD PB7MD1|PB7MD0
#define PB6MD PB6MD1|PB6MD0
#define PB5MD PB5MD1|PB5MD0
#define PB4MD PB4MD1|PB4MD0
#define PB3MD PB3MD1|PB3MD0
#define PB2MD PB2MD1|PB2MD0
#define PB1MD PB1MD1|PB1MD0
#define PB0MD PB0MD1|PB0MD0
#ifdef MHZ
#define BPS 32 * 9600 * MHZ / ( BAUD * 10)
#else
#define BPS 32 /* 9600 for 10 Mhz */
#endif
char getDebugChar (void);
int putDebugChar (char);
void handleError (char theSSR);
void
nop ()
{
}
void
init_serial()
{
int i;
/* Clear TE and RE in Channel 1's SCR */
SCR1 &= ~(SCI_TE | SCI_RE);
/* Set communication to be async, 8-bit data, no parity, 1 stop bit and use internal clock */
SMR1 = 0;
BRR1 = BPS;
SCR1 &= ~(SCI_CKE1 | SCI_CKE0);
/* let the hardware settle */
for (i = 0; i < 1000; i++)
nop ();
/* Turn on in and out */
SCR1 |= SCI_RE | SCI_TE;
/* Set the PFC to make RXD1 (pin PB8) an input pin and TXD1 (pin PB9) an output pin */
PBCR1 &= ~(PB_TXD1 | PB_RXD1);
PBCR1 |= PB_TXD1 | PB_RXD1;
}
int
getDebugCharReady (void)
{
char mySSR;
mySSR = SSR1 & ( SCI_PER | SCI_FER | SCI_ORER );
if ( mySSR )
handleError ( mySSR );
return SSR1 & SCI_RDRF ;
}
char
getDebugChar (void)
{
char ch;
char mySSR;
while ( ! getDebugCharReady())
;
ch = RDR1;
SSR1 &= ~SCI_RDRF;
mySSR = SSR1 & (SCI_PER | SCI_FER | SCI_ORER);
if (mySSR)
handleError (mySSR);
return ch;
}
int
putDebugCharReady()
{
return (SSR1 & SCI_TDRE);
}
int
putDebugChar (char ch)
{
while (!putDebugCharReady())
;
/*
* Write data into TDR and clear TDRE
*/
TDR1 = ch;
SSR1 &= ~SCI_TDRE;
return 1;
}
void
handleError (char theSSR)
{
SSR1 &= ~(SCI_ORER | SCI_PER | SCI_FER);
}