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Diffstat (limited to 'gpxe/src/arch/i386/core/gdbmach.c')
-rw-r--r--gpxe/src/arch/i386/core/gdbmach.c149
1 files changed, 0 insertions, 149 deletions
diff --git a/gpxe/src/arch/i386/core/gdbmach.c b/gpxe/src/arch/i386/core/gdbmach.c
deleted file mode 100644
index 97827ecb..00000000
--- a/gpxe/src/arch/i386/core/gdbmach.c
+++ /dev/null
@@ -1,149 +0,0 @@
-/*
- * Copyright (C) 2008 Stefan Hajnoczi <stefanha@gmail.com>.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include <stddef.h>
-#include <stdio.h>
-#include <assert.h>
-#include <gpxe/uaccess.h>
-#include <gpxe/gdbstub.h>
-#include <gdbmach.h>
-
-/** @file
- *
- * GDB architecture-specific bits for i386
- *
- */
-
-enum {
- DR7_CLEAR = 0x00000400, /* disable hardware breakpoints */
- DR6_CLEAR = 0xffff0ff0, /* clear breakpoint status */
-};
-
-/** Hardware breakpoint, fields stored in x86 bit pattern form */
-struct hwbp {
- int type; /* type (1=write watchpoint, 3=access watchpoint) */
- unsigned long addr; /* linear address */
- size_t len; /* length (0=1-byte, 1=2-byte, 3=4-byte) */
- int enabled;
-};
-
-static struct hwbp hwbps [ 4 ];
-static gdbreg_t dr7 = DR7_CLEAR;
-
-static struct hwbp *gdbmach_find_hwbp ( int type, unsigned long addr, size_t len ) {
- struct hwbp *available = NULL;
- unsigned int i;
- for ( i = 0; i < sizeof hwbps / sizeof hwbps [ 0 ]; i++ ) {
- if ( hwbps [ i ].type == type && hwbps [ i ].addr == addr && hwbps [ i ].len == len ) {
- return &hwbps [ i ];
- }
- if ( !hwbps [ i ].enabled ) {
- available = &hwbps [ i ];
- }
- }
- return available;
-}
-
-static void gdbmach_commit_hwbp ( struct hwbp *bp ) {
- unsigned int regnum = bp - hwbps;
-
- /* Set breakpoint address */
- assert ( regnum < ( sizeof hwbps / sizeof hwbps [ 0 ] ) );
- switch ( regnum ) {
- case 0:
- __asm__ __volatile__ ( "movl %0, %%dr0\n" : : "r" ( bp->addr ) );
- break;
- case 1:
- __asm__ __volatile__ ( "movl %0, %%dr1\n" : : "r" ( bp->addr ) );
- break;
- case 2:
- __asm__ __volatile__ ( "movl %0, %%dr2\n" : : "r" ( bp->addr ) );
- break;
- case 3:
- __asm__ __volatile__ ( "movl %0, %%dr3\n" : : "r" ( bp->addr ) );
- break;
- }
-
- /* Set type */
- dr7 &= ~( 0x3 << ( 16 + 4 * regnum ) );
- dr7 |= bp->type << ( 16 + 4 * regnum );
-
- /* Set length */
- dr7 &= ~( 0x3 << ( 18 + 4 * regnum ) );
- dr7 |= bp->len << ( 18 + 4 * regnum );
-
- /* Set/clear local enable bit */
- dr7 &= ~( 0x3 << 2 * regnum );
- dr7 |= bp->enabled << 2 * regnum;
-}
-
-int gdbmach_set_breakpoint ( int type, unsigned long addr, size_t len, int enable ) {
- struct hwbp *bp;
-
- /* Check and convert breakpoint type to x86 type */
- switch ( type ) {
- case GDBMACH_WATCH:
- type = 0x1;
- break;
- case GDBMACH_AWATCH:
- type = 0x3;
- break;
- default:
- return 0; /* unsupported breakpoint type */
- }
-
- /* Only lengths 1, 2, and 4 are supported */
- if ( len != 2 && len != 4 ) {
- len = 1;
- }
- len--; /* convert to x86 breakpoint length bit pattern */
-
- /* Calculate linear address by adding segment base */
- addr += virt_offset;
-
- /* Set up the breakpoint */
- bp = gdbmach_find_hwbp ( type, addr, len );
- if ( !bp ) {
- return 0; /* ran out of hardware breakpoints */
- }
- bp->type = type;
- bp->addr = addr;
- bp->len = len;
- bp->enabled = enable;
- gdbmach_commit_hwbp ( bp );
- return 1;
-}
-
-static void gdbmach_disable_hwbps ( void ) {
- /* Store and clear hardware breakpoints */
- __asm__ __volatile__ ( "movl %0, %%dr7\n" : : "r" ( DR7_CLEAR ) );
-}
-
-static void gdbmach_enable_hwbps ( void ) {
- /* Clear breakpoint status register */
- __asm__ __volatile__ ( "movl %0, %%dr6\n" : : "r" ( DR6_CLEAR ) );
-
- /* Restore hardware breakpoints */
- __asm__ __volatile__ ( "movl %0, %%dr7\n" : : "r" ( dr7 ) );
-}
-
-__asmcall void gdbmach_handler ( int signo, gdbreg_t *regs ) {
- gdbmach_disable_hwbps();
- gdbstub_handler ( signo, regs );
- gdbmach_enable_hwbps();
-}