NetBSD-5.0.2/sys/arch/acorn26/acorn26/db_interface.c
/* $NetBSD: db_interface.c,v 1.16 2007/10/17 19:52:51 garbled Exp $ */
/*
* Copyright (c) 1996 Scott K. Stevens
*
* Mach Operating System
* Copyright (c) 1991,1990 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* From: db_interface.c,v 2.4 1991/02/05 17:11:13 mrt (CMU)
*/
/*
* Interface to new debugger.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: db_interface.c,v 1.16 2007/10/17 19:52:51 garbled Exp $");
#include "opt_ddb.h"
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/reboot.h>
#include <sys/systm.h> /* just for boothowto */
#include <sys/exec.h>
#include <uvm/uvm_extern.h>
#include <machine/db_machdep.h>
#include <arm/undefined.h>
#include <ddb/db_access.h>
#include <ddb/db_command.h>
#include <ddb/db_output.h>
#include <ddb/db_interface.h>
#include <ddb/db_variables.h>
#include <ddb/db_sym.h>
#include <ddb/db_extern.h>
#include <dev/cons.h>
int db_access_und_sp(const struct db_variable *, db_expr_t *, int);
int db_access_abt_sp(const struct db_variable *, db_expr_t *, int);
int db_access_irq_sp(const struct db_variable *, db_expr_t *, int);
u_int db_fetch_reg(int, db_regs_t *);
int db_trapper(u_int addr, u_int inst, struct trapframe *frame,
int fault_code);
static void db_write_text(unsigned char *, int ch);
const struct db_variable db_regs[] = {
{ "spsr", (long *)&DDB_REGS->tf_spsr, FCN_NULL, },
{ "r0", (long *)&DDB_REGS->tf_r0, FCN_NULL, },
{ "r1", (long *)&DDB_REGS->tf_r1, FCN_NULL, },
{ "r2", (long *)&DDB_REGS->tf_r2, FCN_NULL, },
{ "r3", (long *)&DDB_REGS->tf_r3, FCN_NULL, },
{ "r4", (long *)&DDB_REGS->tf_r4, FCN_NULL, },
{ "r5", (long *)&DDB_REGS->tf_r5, FCN_NULL, },
{ "r6", (long *)&DDB_REGS->tf_r6, FCN_NULL, },
{ "r7", (long *)&DDB_REGS->tf_r7, FCN_NULL, },
{ "r8", (long *)&DDB_REGS->tf_r8, FCN_NULL, },
{ "r9", (long *)&DDB_REGS->tf_r9, FCN_NULL, },
{ "r10", (long *)&DDB_REGS->tf_r10, FCN_NULL, },
{ "r11", (long *)&DDB_REGS->tf_r11, FCN_NULL, },
{ "r12", (long *)&DDB_REGS->tf_r12, FCN_NULL, },
{ "usr_sp", (long *)&DDB_REGS->tf_usr_sp, FCN_NULL, },
{ "usr_lr", (long *)&DDB_REGS->tf_usr_lr, FCN_NULL, },
{ "svc_sp", (long *)&DDB_REGS->tf_svc_sp, FCN_NULL, },
{ "svc_lr", (long *)&DDB_REGS->tf_svc_lr, FCN_NULL, },
{ "pc", (long *)&DDB_REGS->tf_pc, FCN_NULL, },
#ifdef __PROG32
{ "und_sp", (long *)&nil, db_access_und_sp, },
{ "abt_sp", (long *)&nil, db_access_abt_sp, },
{ "irq_sp", (long *)&nil, db_access_irq_sp, },
#endif
};
const struct db_variable * const db_eregs = db_regs + sizeof(db_regs)/sizeof(db_regs[0]);
int db_active = 0;
db_regs_t ddb_regs; /* register state */
#ifdef __PROG32
int
db_access_und_sp(const struct db_variable *vp, db_expr_t *valp, int rw)
{
if (rw == DB_VAR_GET)
*valp = get_stackptr(PSR_UND32_MODE);
return 0;
}
int
db_access_abt_sp(const struct db_variable *vp, db_expr_t valp, int rw)
{
if (rw == DB_VAR_GET)
*valp = get_stackptr(PSR_ABT32_MODE);
return 0;
}
int
db_access_irq_sp(const struct db_variable *vp, db_expr_t *valp, int rw)
{
if (rw == DB_VAR_GET)
*valp = get_stackptr(PSR_IRQ32_MODE);
return 0;
}
#endif /* __PROG32 */
/*
* kdb_trap - field a TRACE or BPT trap
*/
int
kdb_trap(int type, db_regs_t *regs)
{
int s;
switch (type) {
case T_BREAKPOINT: /* breakpoint */
case -1: /* keyboard interrupt */
break;
default:
if (db_recover != 0) {
db_error("Faulted in DDB; continuing...\n");
/*NOTREACHED*/
}
}
/* Should switch to kdb`s own stack here. */
ddb_regs = *regs;
s = splhigh();
db_active++;
cnpollc(true);
db_trap(type, 0/*code*/);
cnpollc(false);
db_active--;
splx(s);
*regs = ddb_regs;
return 1;
}
volatile bool db_validating, db_faulted;
int
db_validate_address(vm_offset_t addr)
{
volatile uint8_t tmp;
db_faulted = false;
db_validating = true;
tmp = *(uint8_t *)addr;
db_validating = false;
return db_faulted;
}
/*
* Read bytes from kernel address space for debugger.
*/
void
db_read_bytes(vm_offset_t addr, size_t size, char *data)
{
char *src;
src = (char *)addr;
for (; size > 0; size--) {
if (db_validate_address((u_int)src)) {
db_printf("address %p is invalid\n", src);
return;
}
*data++ = *src++;
}
}
static void
db_write_text(unsigned char *dst, int ch)
{
if (db_validate_address((u_int)dst)) {
db_printf(" address %p not a valid page\n", dst);
return;
}
*dst = (unsigned char)ch;
}
/*
* Write bytes to kernel address space for debugger.
*/
void
db_write_bytes(vm_offset_t addr, size_t size, const char *data)
{
#if 0
extern char _stext_[], _etext[];
#endif
char *dst;
int loop;
dst = (char *)addr;
loop = size;
while (--loop >= 0) {
#if 0 /* FIXME */
if ((dst >= _stext_) && (dst < _etext))
#endif
db_write_text(dst, *data);
#if 0
else {
if (db_validate_address((u_int)dst)) {
db_printf("address %p is invalid\n", dst);
return;
}
*dst = *data;
}
#endif
dst++, data++;
}
}
const struct db_command db_machine_command_table[] = {
{ DDB_ADD_CMD("bsw", db_bus_write_cmd, CS_MORE, NULL,NULL,NULL) },
{ DDB_ADD_CMD("frame", db_show_frame_cmd, 0, NULL, NULL,NULL) },
{ DDB_ADD_CMD("irqstat",db_irqstat_cmd, 0, NULL, NULL,NULL) },
{ DDB_ADD_CMD("panic", db_show_panic_cmd, 0, NULL, NULL,NULL) },
{ DDB_ADD_CMD( NULL, NULL, 0, NULL, NULL,NULL) }
};
int
db_trapper(u_int addr, u_int inst, trapframe_t *frame, int fault_code)
{
if (fault_code == 0) {
if ((inst & ~INSN_COND_MASK) == (BKPT_INST & ~INSN_COND_MASK))
kdb_trap(T_BREAKPOINT, frame);
else
kdb_trap(-1, frame);
} else
return 1;
return 0;
}
extern u_int esym;
extern u_int end;
static struct undefined_handler db_uh;
void
db_machine_init()
{
/*
* We get called before malloc() is available, so supply a static
* struct undefined_handler.
*/
db_uh.uh_handler = db_trapper;
install_coproc_handler_static(CORE_UNKNOWN_HANDLER, &db_uh);
}
u_int
db_fetch_reg(int reg, db_regs_t *regs)
{
switch (reg) {
case 0:
return regs->tf_r0;
case 1:
return regs->tf_r1;
case 2:
return regs->tf_r2;
case 3:
return regs->tf_r3;
case 4:
return regs->tf_r4;
case 5:
return regs->tf_r5;
case 6:
return regs->tf_r6;
case 7:
return regs->tf_r7;
case 8:
return regs->tf_r8;
case 9:
return regs->tf_r9;
case 10:
return regs->tf_r10;
case 11:
return regs->tf_r11;
case 12:
return regs->tf_r12;
case 13:
return regs->tf_svc_sp;
case 14:
return regs->tf_svc_lr;
case 15:
return regs->tf_pc;
default:
panic("db_fetch_reg: botch");
}
}
u_int
branch_taken(u_int insn, u_int pc, db_regs_t *regs)
{
u_int addr, nregs;
switch ((insn >> 24) & 0xf) {
case 0xa: /* b ... */
case 0xb: /* bl ... */
addr = ((insn << 2) & 0x03ffffff);
if (addr & 0x02000000)
addr |= 0xfc000000;
return pc + 8 + addr;
case 0x7: /* ldr pc, [pc, reg, lsl #2] */
addr = db_fetch_reg(insn & 0xf, regs);
addr = pc + 8 + (addr << 2);
db_read_bytes(addr, 4, (char *)&addr);
return addr;
case 0x1: /* mov pc, reg */
addr = db_fetch_reg(insn & 0xf, regs);
return addr;
case 0x8: /* ldmxx reg, {..., pc} */
case 0x9:
addr = db_fetch_reg((insn >> 16) & 0xf, regs);
nregs = (insn & 0x5555) + ((insn >> 1) & 0x5555);
nregs = (nregs & 0x3333) + ((nregs >> 2) & 0x3333);
nregs = (nregs + (nregs >> 4)) & 0x0f0f;
nregs = (nregs + (nregs >> 8)) & 0x001f;
switch ((insn >> 23) & 0x3) {
case 0x0: /* ldmda */
addr = addr - 0;
break;
case 0x1: /* ldmia */
addr = addr + 0 + ((nregs - 1) << 2);
break;
case 0x2: /* ldmdb */
addr = addr - 4;
break;
case 0x3: /* ldmib */
addr = addr + 4 + ((nregs - 1) << 2);
break;
}
db_read_bytes(addr, 4, (char *)&addr);
return addr;
default:
panic("branch_taken: botch");
}
}