From 4930f0a7f4f3e9269b1c03d4bd1167198c55f269 Mon Sep 17 00:00:00 2001 From: Stu Grossman Date: Mon, 16 Oct 1995 18:25:19 +0000 Subject: [PATCH] * dcache.c: Change default value of remotecache to off. It just screws up too many targets. * sparcl-stub.c: Add prototypes to many forward decls. * Create private copies of strlen, strcpy, and memcpy to prevent chaos when user steps into them. * (trap_low handle_exception): Clean up DSU support code (hardware breakpoints). Move lots of stuff from asm-land to C-land (make it much easier to #ifdef if necessary). Also, use trap 255 to get into break mode instead of doing a DSU register write, which may trash the register. * (putpacket): Don't check return value of putDebugChar. It returns void... --- gdb/ChangeLog | 15 ++++++ gdb/dcache.c | 2 +- gdb/sparcl-stub.c | 134 +++++++++++++++++++++++++++++++++--------------------- 3 files changed, 98 insertions(+), 53 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index e536f5f..29e03c0 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -2,6 +2,21 @@ Sun Oct 15 16:19:27 1995 Stan Shebs * rs6000-tdep.c: Don't include a.out.h, improve some formatting. +Fri Oct 13 15:27:49 1995 Stu Grossman (grossman@cygnus.com) + + * dcache.c: Change default value of remotecache to off. It just + screws up too many targets. + * sparcl-stub.c: Add prototypes to many forward decls. + * Create private copies of strlen, strcpy, and memcpy to prevent + chaos when user steps into them. + * (trap_low handle_exception): Clean up DSU support code + (hardware breakpoints). Move lots of stuff from asm-land to + C-land (make it much easier to #ifdef if necessary). Also, use + trap 255 to get into break mode instead of doing a DSU register + write, which may trash the register. + * (putpacket): Don't check return value of putDebugChar. It + returns void... + Fri Oct 13 14:16:17 1995 steve chamberlain * remote-sim.h: Always include callback.h. diff --git a/gdb/dcache.c b/gdb/dcache.c index 82da4a3..9eec202 100644 --- a/gdb/dcache.c +++ b/gdb/dcache.c @@ -148,7 +148,7 @@ struct dcache_struct int cache_has_stuff; } ; -int remote_dcache = 1; +int remote_dcache = 0; DCACHE *last_cache; /* Used by info dcache */ diff --git a/gdb/sparcl-stub.c b/gdb/sparcl-stub.c index 7a435f3..c7994fe 100644 --- a/gdb/sparcl-stub.c +++ b/gdb/sparcl-stub.c @@ -95,8 +95,8 @@ * 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*/ @@ -105,10 +105,9 @@ extern getDebugChar(); /* read and return a single char */ 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"; @@ -133,6 +132,43 @@ enum regnames {G0, G1, G2, G3, G4, G5, G6, G7, 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 int +strlen (const char *s) +{ + const char *s1 = s; + + while (*s1++ != '\000'); + + return s1 - s; +} + +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 @@ -149,6 +185,18 @@ in_trap_handler: ! 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: @@ -239,9 +287,6 @@ recursive_trap: or %l0, 0xf20, %l4 mov %l4, %psr ! Turn on traps, disable interrupts - nop - nop - nop set 0x1000, %l1 btst %l1, %l0 ! FP enabled? @@ -271,26 +316,6 @@ recursive_trap: 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 @@ -306,24 +331,6 @@ no_fpstore: 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 @@ -470,8 +477,7 @@ putpacket(buffer) while (ch = buffer[count]) { - if (! putDebugChar(ch)) - return; + putDebugChar (ch); checksum += ch; count += 1; } @@ -651,7 +657,7 @@ get_in_break_mode() exceptionHandler (255, dummy_hw_breakpoint); - write_asi (1, 0xff10, 0); + asm ("ta 255"); exceptionHandler (255, trap_low); } @@ -705,7 +711,6 @@ hexToInt(char **ptr, int *intValue) * otherwise. */ - static void handle_exception (registers) unsigned long *registers; @@ -738,6 +743,17 @@ handle_exception (registers) 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]; @@ -916,7 +932,21 @@ handle_exception (registers) 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 */ -- 2.7.4