from ragge;

Handle DDB traps different when we get a panic.
It's more interesting to know the CPU state when panic was called
than in the Debugger() function.

diff --git a/sys/arch/vax/vax/db_machdep.c b/sys/arch/vax/vax/db_machdep.c
index e924f94..07c789e 100644 (file)
--- a/sys/arch/vax/vax/db_machdep.c
+++ b/sys/arch/vax/vax/db_machdep.c
@@ -1,4 +1,4 @@
-/*     $NetBSD: db_machdep.c,v 1.2 1995/07/05 09:54:09 ragge Exp $     */
+/*     $NetBSD: db_machdep.c,v 1.3 1996/01/28 12:05:55 ragge Exp $     */
 
 /* 
  * Mach Operating System
@@ -43,6 +43,7 @@
 
 #include <machine/db_machdep.h>
 #include <machine/trap.h>
+#include <machine/frame.h>
 #include <machine/../vax/gencons.h>
 
 #include <setjmp.h>
@@ -52,7 +53,10 @@ extern jmp_buf       *db_recover;
 int    db_active = 0;
 
 /*
- *  kdb_trap - field a TRACE or BPT trap
+ * DDB is called by either <ESC> - D on keyboard, via a TRACE or
+ * BPT trap or from kernel, normally as a result of a panic.
+ * If it is the result of a panic, set the ddb register frame to
+ * contain the registers when panic was called. (easy to debug).
  */
 int
 kdb_trap(frame)
@@ -60,26 +64,42 @@ kdb_trap(frame)
 {
        int s;
 
-#if 0
-       if ((boothowto&RB_KDB) == 0)
-               return(0);
-#endif
-
        switch (frame->trap) {
        case T_BPTFLT:  /* breakpoint */
        case T_TRCTRAP: /* single_step */
                break;
+
+       case T_KDBTRAP:
+               if (panicstr) {
+                       struct  callsframe *pf, *df;
+
+                       df = (void *)frame->fp; /* start of debug's calls */
+                       pf = (void *)df->ca_fp; /* start of panic's calls */
+                       bcopy(&pf->ca_argno, &ddb_regs.r0, sizeof(int) * 12);
+                       ddb_regs.fp = pf->ca_fp;
+                       ddb_regs.pc = pf->ca_pc;
+                       ddb_regs.ap = pf->ca_ap;
+                       ddb_regs.sp = (unsigned)pf;
+                       ddb_regs.psl = frame->psl & ~0xffe0;
+                       ddb_regs.psl = pf->ca_maskpsw & 0xffe0;
+               }
+               break;
+
        default:
+               if ((boothowto & RB_KDB) == 0)
+                       return 0;
+
                kdbprinttrap(frame->trap, frame->code);
                if (db_recover != 0) {
                        db_error("Faulted in DDB; continuing...\n");
                        /*NOTREACHED*/
                }
        }
-       bcopy(frame, &ddb_regs, sizeof(struct trapframe));
 
-       /* XXX Should switch to interrupt stack here. */
+       if (!panicstr)
+               bcopy(frame, &ddb_regs, sizeof(struct trapframe));
 
+       /* XXX Should switch to interrupt stack here, if needed. */
 
        s = splddb();
        mtpr(0, PR_RXCS);
@@ -91,7 +111,9 @@ kdb_trap(frame)
        mtpr(GC_TIE, PR_TXCS);
        splx(s);
 
-       bcopy(&ddb_regs, frame, sizeof(struct trapframe));
+       if (!panicstr)
+               bcopy(&ddb_regs, frame, sizeof(struct trapframe));
+       frame->sp = mfpr(PR_USP);
 
        return (1);
 }
@@ -140,7 +162,7 @@ db_write_bytes(addr, size, data)
 {
        register char   *dst;
 
-       dst = addr;
+       dst = (char *)addr;
        for (;size;size--)
                *dst++ = *data++;
 }
@@ -155,7 +177,6 @@ Debugger()
 
 /*
  * Machine register set.
- * XXX - lost stackpointer.
  */
 struct db_variable db_regs[] = {
        "r0",   &ddb_regs.r0,   FCN_NULL,
@@ -172,6 +193,7 @@ struct db_variable db_regs[] = {
        "r11",  &ddb_regs.r11,  FCN_NULL,
        "ap",   &ddb_regs.ap,   FCN_NULL,
        "fp",   &ddb_regs.fp,   FCN_NULL,
+       "sp",   &ddb_regs.sp,   FCN_NULL,
        "pc",   &ddb_regs.pc,   FCN_NULL,
        "psl",  &ddb_regs.psl,  FCN_NULL,
 };
@@ -196,6 +218,7 @@ kdbrint(tkn)
 
        if (ddbescape && ((tkn & 0x7f) == 'D')) {
                mtpr(0xf, PR_SIRR);
+               ddbescape = 0;
                return 1;
        }