*
* g return the value of the CPU registers hex data or ENN
* G set the value of the CPU registers OK or ENN
+ * P set the value of a single CPU register OK or ENN
*
* mAA..AA,LLLL Read LLLL bytes at address AA..AA hex data or ENN
* MAA..AA,LLLL: Write LLLL bytes at address AA.AA OK or ENN
*
* ? What was the last sigval ? SNN (signal NN)
*
- * bBB..BB Set baud rate to BB..BB OK or BNN, then sets
- * baud rate
- *
* All commands and responses are sent with a packet which includes a
* checksum. A packet consists of
*
* external low-level support routines
*/
-extern putDebugChar(); /* write a single character */
-extern getDebugChar(); /* read and return a single char */
+extern void putDebugChar (int c); /* write a single character */
+extern int getDebugChar (void); /* read and return a single char */
/************************************************************************/
/* BUFMAX defines the maximum number of characters in inbound/outbound buffers*/
static int initialized = 0; /* !0 means we've been initialized */
-extern void breakinst();
-static void hw_breakpoint();
-static void set_mem_fault_trap();
-static void get_in_break_mode();
+extern void breakinst ();
+static void set_mem_fault_trap (int enable);
+static void get_in_break_mode (void);
static const char hexchars[]="0123456789abcdef";
extern void trap_low();
+/* Create private copies of common functions used by the stub. This prevents
+ nasty interactions between app code and the stub (for instance if user steps
+ into strlen, etc..) */
+
+static char *
+strcpy (char *dst, const char *src)
+{
+ char *retval = dst;
+
+ while ((*dst++ = *src++) != '\000');
+
+ return retval;
+}
+
+static void *
+memcpy (void *vdst, const void *vsrc, int n)
+{
+ char *dst = vdst;
+ const char *src = vsrc;
+ char *retval = dst;
+
+ while (n-- > 0)
+ *dst++ = *src++;
+
+ return retval;
+}
+
asm("
.reserve trapstack, 1000 * 4, \"bss\", 8
! 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.
+!
+! On entry, trap_low expects l1 and l2 to contain pc and npc respectivly.
+! Register usage throughout the routine is as follows:
+!
+! l0 - psr
+! l1 - pc
+! l2 - npc
+! l3 - wim
+! l4 - scratch and y reg
+! l5 - scratch and tbr
+! l6 - unused
+! l7 - unused
.globl _trap_low
_trap_low:
or %l0, 0xf20, %l4
mov %l4, %psr ! Turn on traps, disable interrupts
- nop
- nop
- nop
set 0x1000, %l1
btst %l1, %l0 ! FP enabled?
std %f30, [%sp + (24 + 62) * 4]
no_fpstore:
- call _get_in_break_mode
- nop
-
- set 0xff00, %l3
- ldda [%l3]0x1, %l4
- std %l4, [%sp + (24 + 72) * 4] ! DIA1, debug instr addr 1
- ! DIA2, debug instr addr 2
- inc 8, %l3
- ldda [%l3]0x1, %l4
- std %l4, [%sp + (24 + 74) * 4] ! DDA1, debug data addr 1
- ! DDA2, debug data addr 2
- inc 8, %l3
- ldda [%l3]0x1, %l4
- std %l4, [%sp + (24 + 76) * 4] ! DDV1, debug data val 1
- ! DDV2, debug data val 2
- inc 8, %l3
- ldda [%l3]0x1, %l4
- std %l4, [%sp + (24 + 78) * 4] ! DCR, debug control reg
- ! DSR, debug status reg
-
call _handle_exception
add %sp, 24 * 4, %o0 ! Pass address of registers
ldd [%sp + (24 + 12) * 4], %i4
ldd [%sp + (24 + 14) * 4], %i6
- set 0xff00, %l2
- ldd [%sp + (24 + 72) * 4], %l4
- stda %l4, [%l2]0x1 ! DIA1, debug instr addr 1
- ! DIA2, debug instr addr 2
- inc 8, %l2
- ldd [%sp + (24 + 74) * 4], %l4
- stda %l4, [%l2]0x1 ! DDA1, debug data addr 1
- ! DDA2, debug data addr 2
- inc 8, %l2
- ldd [%sp + (24 + 76) * 4], %l4
- stda %l4, [%l2]0x1 ! DDV1, debug data value 1
- ! DDV2, debug data val 2
- inc 8, %l2
- ldd [%sp + (24 + 78) * 4], %l4
- bset 0x200, %l4
- stda %l4, [%l2]0x1 ! DCR, debug control reg
- ! DSR, debug control reg
-
ldd [%sp + (24 + 64) * 4], %l0 ! Y & PSR
ldd [%sp + (24 + 68) * 4], %l2 ! PC & NPC
/* Convert ch from a hex digit to an int */
static int
-hex(ch)
- unsigned char ch;
+hex (unsigned char ch)
{
if (ch >= 'a' && ch <= 'f')
return ch-'a'+10;
return -1;
}
+static char remcomInBuffer[BUFMAX];
+static char remcomOutBuffer[BUFMAX];
+
/* scan for the sequence $<data>#<checksum> */
-static void
-getpacket(buffer)
- char *buffer;
+unsigned char *
+getpacket (void)
{
+ unsigned char *buffer = &remcomInBuffer[0];
unsigned char checksum;
unsigned char xmitcsum;
- int i;
int count;
- unsigned char ch;
+ char ch;
- do
+ while (1)
{
/* wait around for the start character, ignore all other characters */
- while ((ch = (getDebugChar() & 0x7f)) != '$') ;
+ while ((ch = getDebugChar ()) != '$')
+ ;
+retry:
checksum = 0;
xmitcsum = -1;
-
count = 0;
/* now, read until a # or end of buffer is found */
while (count < BUFMAX)
{
- ch = getDebugChar() & 0x7f;
+ ch = getDebugChar ();
+ if (ch == '$')
+ goto retry;
if (ch == '#')
break;
checksum = checksum + ch;
buffer[count] = ch;
count = count + 1;
}
-
- if (count >= BUFMAX)
- continue;
-
buffer[count] = 0;
if (ch == '#')
{
- xmitcsum = hex(getDebugChar() & 0x7f) << 4;
- xmitcsum |= hex(getDebugChar() & 0x7f);
-#if 0
- /* Humans shouldn't have to figure out checksums to type to it. */
- putDebugChar ('+');
- return;
-#endif
+ ch = getDebugChar ();
+ xmitcsum = hex (ch) << 4;
+ ch = getDebugChar ();
+ xmitcsum += hex (ch);
+
if (checksum != xmitcsum)
- putDebugChar('-'); /* failed checksum */
+ {
+ putDebugChar ('-'); /* failed checksum */
+ }
else
{
- putDebugChar('+'); /* successful transfer */
+ 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];
+ putDebugChar (buffer[0]);
+ putDebugChar (buffer[1]);
+
+ return &buffer[3];
}
+
+ return &buffer[0];
}
}
}
- while (checksum != xmitcsum);
}
/* send the packet in buffer. */
static void
-putpacket(buffer)
- unsigned char *buffer;
+putpacket (unsigned char *buffer)
{
unsigned char checksum;
int count;
while (ch = buffer[count])
{
- if (! putDebugChar(ch))
- return;
+ putDebugChar (ch);
checksum += ch;
count += 1;
}
putDebugChar(hexchars[checksum & 0xf]);
}
- while ((getDebugChar() & 0x7f) != '+');
+ while (getDebugChar() != '+');
}
-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;
*/
static unsigned char *
-mem2hex(mem, buf, count, may_fault)
- unsigned char *mem;
- unsigned char *buf;
- int count;
- int may_fault;
+mem2hex (unsigned char *mem, unsigned char *buf, int count, int may_fault)
{
unsigned char ch;
* 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;
+hex2mem (unsigned char *buf, unsigned char *mem, int count, int may_fault)
{
int i;
unsigned char ch;
/* Set up exception handlers for tracing and breakpoints */
void
-set_debug_traps()
+set_debug_traps (void)
{
struct hard_trap_info *ht;
if (ht->tt != 4 || ! (read_psr () & 0x1000))
exceptionHandler(ht->tt, trap_low);
- /* In case GDB is started before us, ack any packets (presumably
- "$?#xx") sitting there. */
-
- putDebugChar ('+');
-
initialized = 1;
}
");
static void
-set_mem_fault_trap(enable)
- int enable;
+set_mem_fault_trap (int enable)
{
extern void fltr_set_mem_err();
mem_err = 0;
");
static void
-get_in_break_mode()
+get_in_break_mode (void)
{
extern void dummy_hw_breakpoint();
exceptionHandler (255, dummy_hw_breakpoint);
- write_asi (1, 0xff10, 0);
+ asm ("ta 255");
exceptionHandler (255, trap_low);
}
/* Convert the SPARC hardware trap type code to a unix signal number. */
static int
-computeSignal(tt)
- int tt;
+computeSignal (int tt)
{
struct hard_trap_info *ht;
* otherwise.
*/
-
static void
-handle_exception (registers)
- unsigned long *registers;
+handle_exception (unsigned long *registers)
{
int tt; /* Trap type */
int sigval;
restore
");
+ get_in_break_mode (); /* Enable DSU register writes */
+
+ registers[DIA1] = read_asi (1, 0xff00);
+ registers[DIA2] = read_asi (1, 0xff04);
+ registers[DDA1] = read_asi (1, 0xff08);
+ registers[DDA2] = read_asi (1, 0xff0c);
+ registers[DDV1] = read_asi (1, 0xff10);
+ registers[DDV2] = read_asi (1, 0xff14);
+ registers[DCR] = read_asi (1, 0xff18);
+ registers[DSR] = read_asi (1, 0xff1c);
+
if (registers[PC] == (unsigned long)breakinst)
{
registers[PC] = registers[NPC];
{
remcomOutBuffer[0] = 0;
- getpacket(remcomInBuffer);
- switch (remcomInBuffer[0])
+ ptr = getpacket();
+ switch (*ptr++)
{
case '?':
remcomOutBuffer[0] = 'S';
psr = registers[PSR];
- ptr = &remcomInBuffer[1];
-
- if (remcomInBuffer[0] == 'P')
+ if (ptr[-1] == 'P')
{
int regno;
hex2mem (ptr, (char *)®isters[regno], 4, 0);
else
{
- strcpy (remcomOutBuffer, "P01");
+ strcpy (remcomOutBuffer, "E01");
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))
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)
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;
some location may have changed something that is in the instruction cache.
*/
- flush_i_cache();
+ flush_i_cache ();
+
+ if (!(registers[DSR] & 0x1) /* DSU enabled? */
+ && !(registers[DCR] & 0x200)) /* Are we in break state? */
+ { /* Yes, set the DSU regs */
+ write_asi (1, 0xff00, registers[DIA1]);
+ write_asi (1, 0xff04, registers[DIA2]);
+ write_asi (1, 0xff08, registers[DDA1]);
+ write_asi (1, 0xff0c, registers[DDA2]);
+ write_asi (1, 0xff10, registers[DDV1]);
+ write_asi (1, 0xff14, registers[DDV2]);
+ write_asi (1, 0xff1c, registers[DSR]);
+ write_asi (1, 0xff18, registers[DCR] | 0x200); /* Clear break */
+ }
+
return;
/* kill the program */
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 */
the debugger. */
void
-breakpoint()
+breakpoint (void)
{
if (!initialized)
return;