#include <string.h>
#include <signal.h>
extern void putDebugChar();
extern int getDebugChar();
#define BUFMAX 2048
static int initialized = 0;
static void set_mem_fault_trap();
static const char hexchars[]="0123456789abcdef";
#define NUMREGS 72
#define NUMREGBYTES (NUMREGS * 4)
enum regnames {G0, G1, G2, G3, G4, G5, G6, G7,
O0, O1, O2, O3, O4, O5, SP, O7,
L0, L1, L2, L3, L4, L5, L6, L7,
I0, I1, I2, I3, I4, I5, FP, I7,
F0, F1, F2, F3, F4, F5, F6, F7,
F8, F9, F10, F11, F12, F13, F14, F15,
F16, F17, F18, F19, F20, F21, F22, F23,
F24, F25, F26, F27, F28, F29, F30, F31,
Y, PSR, WIM, TBR, PC, NPC, FPSR, CPSR };
extern void trap_low();
asm("
.reserve trapstack, 1000 * 4, \"bss\", 8
.data
.align 4
in_trap_handler:
.word 0
.text
.align 4
! This function is called when any SPARC trap (except window overflow or
! underflow) occurs. It makes sure that the invalid register window is still
! available before jumping into C code. It will also restore the world if you
! return from handle_exception.
.globl _trap_low
_trap_low:
mov %psr, %l0
mov %wim, %l3
srl %l3, %l0, %l4 ! wim >> cwp
cmp %l4, 1
bne window_fine ! Branch if not in the invalid window
nop
! Handle window overflow
mov %g1, %l4 ! Save g1, we use it to hold the wim
srl %l3, 1, %g1 ! Rotate wim right
tst %g1
bg good_wim ! Branch if new wim is non-zero
nop
! At this point, we need to bring a 1 into the high order bit of the wim.
! Since we don't want to make any assumptions about the number of register
! windows, we figure it out dynamically so as to setup the wim correctly.
not %g1 ! Fill g1 with ones
mov %g1, %wim ! Fill the wim with ones
nop
nop
nop
mov %wim, %g1 ! Read back the wim
inc %g1 ! Now g1 has 1 just to left of wim
srl %g1, 1, %g1 ! Now put 1 at top of wim
mov %g0, %wim ! Clear wim so that subsequent save
nop ! won't trap
nop
nop
good_wim:
save %g0, %g0, %g0 ! Slip into next window
mov %g1, %wim ! Install the new wim
std %l0, [%sp + 0 * 4] ! save L & I registers
std %l2, [%sp + 2 * 4]
std %l4, [%sp + 4 * 4]
std %l6, [%sp + 6 * 4]
std %i0, [%sp + 8 * 4]
std %i2, [%sp + 10 * 4]
std %i4, [%sp + 12 * 4]
std %i6, [%sp + 14 * 4]
restore ! Go back to trap window.
mov %l4, %g1 ! Restore %g1
window_fine:
sethi %hi(in_trap_handler), %l4
ld [%lo(in_trap_handler) + %l4], %l5
tst %l5
bg recursive_trap
inc %l5
set trapstack+1000*4, %sp ! Switch to trap stack
recursive_trap:
st %l5, [%lo(in_trap_handler) + %l4]
sub %sp,(16+1+6+1+72)*4,%sp ! Make room for input & locals
! + hidden arg + arg spill
! + doubleword alignment
! + registers[72] local var
std %g0, [%sp + (24 + 0) * 4] ! registers[Gx]
std %g2, [%sp + (24 + 2) * 4]
std %g4, [%sp + (24 + 4) * 4]
std %g6, [%sp + (24 + 6) * 4]
std %i0, [%sp + (24 + 8) * 4] ! registers[Ox]
std %i2, [%sp + (24 + 10) * 4]
std %i4, [%sp + (24 + 12) * 4]
std %i6, [%sp + (24 + 14) * 4]
! F0->F31 not implemented
mov %y, %l4
mov %tbr, %l5
st %l4, [%sp + (24 + 64) * 4] ! Y
st %l0, [%sp + (24 + 65) * 4] ! PSR
st %l3, [%sp + (24 + 66) * 4] ! WIM
st %l5, [%sp + (24 + 67) * 4] ! TBR
st %l1, [%sp + (24 + 68) * 4] ! PC
st %l2, [%sp + (24 + 69) * 4] ! NPC
! CPSR and FPSR not impl
or %l0, 0xf20, %l4
mov %l4, %psr ! Turn on traps, disable interrupts
call _handle_exception
add %sp, 24 * 4, %o0 ! Pass address of registers
! Reload all of the registers that aren't on the stack
ld [%sp + (24 + 1) * 4], %g1 ! registers[Gx]
ldd [%sp + (24 + 2) * 4], %g2
ldd [%sp + (24 + 4) * 4], %g4
ldd [%sp + (24 + 6) * 4], %g6
ldd [%sp + (24 + 8) * 4], %i0 ! registers[Ox]
ldd [%sp + (24 + 10) * 4], %i2
ldd [%sp + (24 + 12) * 4], %i4
ldd [%sp + (24 + 14) * 4], %i6
ldd [%sp + (24 + 64) * 4], %l0 ! Y & PSR
ldd [%sp + (24 + 68) * 4], %l2 ! PC & NPC
restore ! Ensure that previous window is valid
save %g0, %g0, %g0 ! by causing a window_underflow trap
mov %l0, %y
mov %l1, %psr ! Make sure that traps are disabled
! for rett
sethi %hi(in_trap_handler), %l4
ld [%lo(in_trap_handler) + %l4], %l5
dec %l5
st %l5, [%lo(in_trap_handler) + %l4]
jmpl %l2, %g0 ! Restore old PC
rett %l3 ! Restore old nPC
");
static int
hex (unsigned 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;
}
static char remcomInBuffer[BUFMAX];
static char remcomOutBuffer[BUFMAX];
unsigned char *
getpacket (void)
{
unsigned char *buffer = &remcomInBuffer[0];
unsigned char checksum;
unsigned char xmitcsum;
int count;
char ch;
while (1)
{
while ((ch = getDebugChar ()) != '$')
;
retry:
checksum = 0;
xmitcsum = -1;
count = 0;
while (count < BUFMAX)
{
ch = getDebugChar ();
if (ch == '$')
goto retry;
if (ch == '#')
break;
checksum = checksum + ch;
buffer[count] = ch;
count = count + 1;
}
buffer[count] = 0;
if (ch == '#')
{
ch = getDebugChar ();
xmitcsum = hex (ch) << 4;
ch = getDebugChar ();
xmitcsum += hex (ch);
if (checksum != xmitcsum)
{
putDebugChar ('-');
}
else
{
putDebugChar ('+');
if (buffer[2] == ':')
{
putDebugChar (buffer[0]);
putDebugChar (buffer[1]);
return &buffer[3];
}
return &buffer[0];
}
}
}
}
static void
putpacket (unsigned char *buffer)
{
unsigned char checksum;
int count;
unsigned char ch;
do
{
putDebugChar('$');
checksum = 0;
count = 0;
while (ch = buffer[count])
{
putDebugChar(ch);
checksum += ch;
count += 1;
}
putDebugChar('#');
putDebugChar(hexchars[checksum >> 4]);
putDebugChar(hexchars[checksum & 0xf]);
}
while (getDebugChar() != '+');
}
static volatile int mem_err = 0;
static unsigned char *
mem2hex (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;
}
static char *
hex2mem (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;
}
static struct hard_trap_info
{
unsigned char tt;
unsigned char signo;
} hard_trap_info[] = {
{1, SIGSEGV},
{2, SIGILL},
{3, SIGILL},
{4, SIGEMT},
{36, SIGEMT},
{7, SIGBUS},
{9, SIGSEGV},
{10, SIGEMT},
{128+1, SIGTRAP},
{0, 0}
};
void
set_debug_traps (void)
{
struct hard_trap_info *ht;
for (ht = hard_trap_info; ht->tt && ht->signo; ht++)
exceptionHandler(ht->tt, trap_low);
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
_fltr_set_mem_err:
sethi %hi(_mem_err), %l0
st %l1, [%l0 + %lo(_mem_err)]
jmpl %l2, %g0
rett %l2+4
");
static void
set_mem_fault_trap (int enable)
{
extern void fltr_set_mem_err();
mem_err = 0;
if (enable)
exceptionHandler(9, fltr_set_mem_err);
else
exceptionHandler(9, trap_low);
}
static int
computeSignal (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;
}
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);
}
extern void breakinst();
static void
handle_exception (unsigned long *registers)
{
int tt;
int sigval;
int addr;
int length;
char *ptr;
unsigned long *sp;
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];
tt = (registers[TBR] >> 4) & 0xff;
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);
*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);
while (1)
{
remcomOutBuffer[0] = 0;
ptr = getpacket();
switch (*ptr++)
{
case '?':
remcomOutBuffer[0] = 'S';
remcomOutBuffer[1] = hexchars[sigval >> 4];
remcomOutBuffer[2] = hexchars[sigval & 0xf];
remcomOutBuffer[3] = 0;
break;
case 'd':
break;
case 'g':
{
ptr = remcomOutBuffer;
ptr = mem2hex((char *)registers, ptr, 16 * 4, 0);
ptr = mem2hex(sp + 0, ptr, 16 * 4, 0);
memset(ptr, '0', 32 * 8);
mem2hex((char *)®isters[Y],
ptr + 32 * 4 * 2,
8 * 4,
0);
}
break;
case 'G':
{
unsigned long *newsp, psr;
psr = registers[PSR];
hex2mem(ptr, (char *)registers, 16 * 4, 0);
hex2mem(ptr + 16 * 4 * 2, sp + 0, 16 * 4, 0);
hex2mem(ptr + 64 * 4 * 2, (char *)®isters[Y],
8 * 4, 0);
newsp = (unsigned long *)registers[SP];
if (sp != newsp)
sp = memcpy(newsp, sp, 16 * 4);
if (psr != registers[PSR])
registers[PSR] = (psr & 0x1f) | (registers[PSR] & ~0x1f);
strcpy(remcomOutBuffer,"OK");
}
break;
case 'm':
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':
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':
if (hexToInt(&ptr, &addr))
{
registers[PC] = addr;
registers[NPC] = addr + 4;
}
flush_i_cache();
return;
case 'k' :
break;
#if 0
case 't':
asm (" std %f30,[%sp]");
break;
#endif
case 'r':
asm ("call 0
nop ");
break;
}
putpacket(remcomOutBuffer);
}
}
void
breakpoint (void)
{
if (!initialized)
return;
asm(" .globl _breakinst
_breakinst: ta 1
");
}