*
* Modified for SPARC by Stu Grossman, Cygnus Support.
*
+ * This code has been extensively tested on the Fujitsu SPARClite demo board.
+ *
* To enable debugger support, two things need to happen. One, a
* call to set_debug_traps() is necessary in order to allow any breakpoints
* or error conditions to be properly intercepted and reported to gdb.
*
* ? 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
*
#include <string.h>
#include <signal.h>
-#include <memory.h>
/************************************************************************
*
* external low-level support routines
*/
-extern putDebugChar(); /* write a single character */
-extern getDebugChar(); /* read and return a single char */
+extern void putDebugChar(); /* write a single character */
+extern int getDebugChar(); /* read and return a single char */
/************************************************************************/
/* BUFMAX defines the maximum number of characters in inbound/outbound buffers*/
mov %g1, %l4 ! Save g1, we use it to hold the wim
srl %l3, 1, %g1 ! Rotate wim right
- sll %l3, 8-1, %l5
- or %l5, %g1, %g1
+ 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
call _handle_exception
add %sp, 24 * 4, %o0 ! Pass address of registers
- restore ! Ensure that previous window is valid
- save %g0, %g0, %g0 ! by causing a window_underflow trap
-
! Reload all of the registers that aren't on the stack
ld [%sp + (24 + 1) * 4], %g1 ! registers[Gx]
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
return -1;
}
+static char remcomInBuffer[BUFMAX];
+static char remcomOutBuffer[BUFMAX];
+
/* scan for the sequence $<data>#<checksum> */
-static void
-getpacket(buffer)
- char *buffer;
+unsigned char *
+getpacket ()
{
+ unsigned char *buffer = &remcomInBuffer[0];
unsigned char checksum;
unsigned char xmitcsum;
- int i;
int count;
- unsigned char ch;
+ char ch;
- do
+ while (1)
{
/* wait around for the start character, ignore all other characters */
- while ((ch = getDebugChar()) != '$') ;
+ while ((ch = getDebugChar ()) != '$')
+ ;
+retry:
checksum = 0;
xmitcsum = -1;
-
count = 0;
/* now, read until a # or end of buffer is found */
while (count < BUFMAX)
{
- ch = getDebugChar();
+ ch = getDebugChar ();
+ if (ch == '$')
+ 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()) << 4;
- xmitcsum |= hex(getDebugChar());
-#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. */
while (ch = buffer[count])
{
- if (! putDebugChar(ch))
- return;
+ putDebugChar(ch);
checksum += ch;
count += 1;
}
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;
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;
}
{
remcomOutBuffer[0] = 0;
- getpacket(remcomInBuffer);
- switch (remcomInBuffer[0])
+ ptr = getpacket();
+ switch (*ptr++)
{
case '?':
remcomOutBuffer[0] = 'S';
remcomOutBuffer[3] = 0;
break;
- case 'd':
- /* toggle debug flag */
+ case 'd': /* toggle debug flag */
break;
case 'g': /* return the value of the CPU registers */
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],
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;
break;
#if 0
case 't': /* Test feature */
- asm (" std %f31,[%sp]");
+ 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 */