#include "config.h"
#endif
-#include "armv4_5.h" /* REVISIT to become arm.h */
+#include "arm.h"
#include "arm_dpm.h"
#include <jtag/jtag.h>
#include "register.h"
#include "breakpoints.h"
#include "target_type.h"
+#include "arm_opcodes.h"
/**
* Implements various ARM DPM operations using architectural debug registers.
* These routines layer over core-specific communication methods to cope with
* implementation differences between cores like ARM1136 and Cortex-A8.
+ *
+ * The "Debug Programmers' Model" (DPM) for ARMv6 and ARMv7 is defined by
+ * Part C (Debug Architecture) of the ARM Architecture Reference Manual,
+ * ARMv7-A and ARMv7-R edition (ARM DDI 0406B). In OpenOCD, DPM operations
+ * are abstracted through internal programming interfaces to share code and
+ * to minimize needless differences in debug behavior between cores.
*/
/*----------------------------------------------------------------------*/
return retval;
}
+/* Avoid needless I/O ... leave breakpoints and watchpoints alone
+ * unless they're removed, or need updating because of single-stepping
+ * or running debugger code.
+ */
+static int dpm_maybe_update_bpwp(struct arm_dpm *dpm, bool bpwp,
+ struct dpm_bpwp *xp, int *set_p)
+{
+ int retval = ERROR_OK;
+ bool disable;
+
+ if (!set_p) {
+ if (!xp->dirty)
+ goto done;
+ xp->dirty = false;
+ /* removed or startup; we must disable it */
+ disable = true;
+ } else if (bpwp) {
+ if (!xp->dirty)
+ goto done;
+ /* disabled, but we must set it */
+ xp->dirty = disable = false;
+ *set_p = true;
+ } else {
+ if (!*set_p)
+ goto done;
+ /* set, but we must temporarily disable it */
+ xp->dirty = disable = true;
+ *set_p = false;
+ }
+
+ if (disable)
+ retval = dpm->bpwp_disable(dpm, xp->number);
+ else
+ retval = dpm->bpwp_enable(dpm, xp->number,
+ xp->address, xp->control);
+
+ if (retval != ERROR_OK)
+ LOG_ERROR("%s: can't %s HW %spoint %d",
+ disable ? "disable" : "enable",
+ target_name(dpm->arm->target),
+ (xp->number < 16) ? "break" : "watch",
+ xp->number & 0xf);
+done:
+ return retval;
+}
+
+static int dpm_add_breakpoint(struct target *target, struct breakpoint *bp);
+
/**
* Writes all modified core registers for all processor modes. In normal
* operation this is called on exit from halting debug state.
if (retval != ERROR_OK)
goto done;
+ /* If we're managing hardware breakpoints for this core, enable
+ * or disable them as requested.
+ *
+ * REVISIT We don't yet manage them for ANY cores. Eventually
+ * we should be able to assume we handle them; but until then,
+ * cope with the hand-crafted breakpoint code.
+ */
+ if (arm->target->type->add_breakpoint == dpm_add_breakpoint) {
+ for (unsigned i = 0; i < dpm->nbp; i++) {
+ struct dpm_bp *dbp = dpm->dbp + i;
+ struct breakpoint *bp = dbp->bp;
+
+ retval = dpm_maybe_update_bpwp(dpm, bpwp, &dbp->bpwp,
+ bp ? &bp->set : NULL);
+ }
+ }
+
/* enable/disable watchpoints */
for (unsigned i = 0; i < dpm->nwp; i++) {
struct dpm_wp *dwp = dpm->dwp + i;
struct watchpoint *wp = dwp->wp;
- bool disable;
-
- /* Avoid needless I/O ... leave watchpoints alone
- * unless they're removed, or need updating because
- * of single-stepping or running debugger code.
- */
- if (!wp) {
- if (!dwp->dirty)
- continue;
- dwp->dirty = false;
- /* removed or startup; we must disable it */
- disable = true;
- } else if (bpwp) {
- if (!dwp->dirty)
- continue;
- /* disabled, but we must set it */
- dwp->dirty = disable = false;
- wp->set = true;
- } else {
- if (!wp->set)
- continue;
- /* set, but we must temporarily disable it */
- dwp->dirty = disable = true;
- wp->set = false;
- }
-
- if (disable)
- retval = dpm->bpwp_disable(dpm, 16 + i);
- else
- retval = dpm->bpwp_enable(dpm, 16 + i,
- wp->address & ~3, dwp->control);
- if (retval != ERROR_OK)
- LOG_ERROR("%s: can't %s HW watchpoint %d",
- target_name(arm->target),
- disable ? "disable" : "enable",
- i);
+ retval = dpm_maybe_update_bpwp(dpm, bpwp, &dwp->bpwp,
+ wp ? &wp->set : NULL);
}
/* NOTE: writes to breakpoint and watchpoint registers might
retval = dpm_modeswitch(dpm, ARM_MODE_ANY);
arm->cpsr->dirty = false;
- retval = dpm_write_reg(dpm, &cache->reg_list[15], 15);
- cache->reg_list[15].dirty = false;
+ retval = dpm_write_reg(dpm, arm->pc, 15);
+ arm->pc->dirty = false;
/* flush R0 -- it's *very* dirty by now */
retval = dpm_write_reg(dpm, &cache->reg_list[0], 0);
* fact isn't currently leveraged.
*/
-static int dpm_watchpoint_setup(struct arm_dpm *dpm, unsigned index,
- struct watchpoint *wp)
+static int dpm_bpwp_setup(struct arm_dpm *dpm, struct dpm_bpwp *xp,
+ uint32_t addr, uint32_t length)
{
- uint32_t addr = wp->address;
uint32_t control;
- /* this hardware doesn't support data value matching or masking */
- if (wp->value || wp->mask != ~(uint32_t)0) {
- LOG_DEBUG("watchpoint values and masking not supported");
- return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
- }
-
control = (1 << 0) /* enable */
| (3 << 1); /* both user and privileged access */
- switch (wp->rw) {
- case WPT_READ:
- control |= 1 << 3;
- break;
- case WPT_WRITE:
- control |= 2 << 3;
- break;
- case WPT_ACCESS:
- control |= 3 << 3;
- break;
- }
-
/* Match 1, 2, or all 4 byte addresses in this word.
*
- * FIXME: v7 hardware allows lengths up to 2 GB, and has eight
- * byte address select bits. Support larger wp->length, if addr
- * is suitably aligned.
+ * FIXME: v7 hardware allows lengths up to 2 GB for BP and WP.
+ * Support larger length, when addr is suitably aligned. In
+ * particular, allow watchpoints on 8 byte "double" values.
+ *
+ * REVISIT allow watchpoints on unaligned 2-bit values; and on
+ * v7 hardware, unaligned 4-byte ones too.
*/
- switch (wp->length) {
+ switch (length) {
case 1:
control |= (1 << (addr & 3)) << 5;
- addr &= ~3;
break;
case 2:
/* require 2-byte alignment */
}
/* FALL THROUGH */
default:
- LOG_DEBUG("bad watchpoint length or alignment");
+ LOG_ERROR("unsupported {break,watch}point length/alignment");
return ERROR_INVALID_ARGUMENTS;
}
- /* other control bits:
- * bits 9:12 == 0 ... only checking up to four byte addresses (v7 only)
+ /* other shared control bits:
* bits 15:14 == 0 ... both secure and nonsecure states (v6.1+ only)
* bit 20 == 0 ... not linked to a context ID
* bit 28:24 == 0 ... not ignoring N LSBs (v7 only)
*/
- dpm->dwp[index].wp = wp;
- dpm->dwp[index].control = control;
- dpm->dwp[index].dirty = true;
+ xp->address = addr & ~3;
+ xp->control = control;
+ xp->dirty = true;
+
+ LOG_DEBUG("BPWP: addr %8.8x, control %x, number %d",
+ xp->address, control, xp->number);
/* hardware is updated in write_dirty_registers() */
return ERROR_OK;
}
+static int dpm_add_breakpoint(struct target *target, struct breakpoint *bp)
+{
+ struct arm *arm = target_to_arm(target);
+ struct arm_dpm *dpm = arm->dpm;
+ int retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+
+ if (bp->length < 2)
+ return ERROR_INVALID_ARGUMENTS;
+ if (!dpm->bpwp_enable)
+ return retval;
+
+ /* FIXME we need a generic solution for software breakpoints. */
+ if (bp->type == BKPT_SOFT)
+ LOG_DEBUG("using HW bkpt, not SW...");
+
+ for (unsigned i = 0; i < dpm->nbp; i++) {
+ if (!dpm->dbp[i].bp) {
+ retval = dpm_bpwp_setup(dpm, &dpm->dbp[i].bpwp,
+ bp->address, bp->length);
+ if (retval == ERROR_OK)
+ dpm->dbp[i].bp = bp;
+ break;
+ }
+ }
+
+ return retval;
+}
+
+static int dpm_remove_breakpoint(struct target *target, struct breakpoint *bp)
+{
+ struct arm *arm = target_to_arm(target);
+ struct arm_dpm *dpm = arm->dpm;
+ int retval = ERROR_INVALID_ARGUMENTS;
+
+ for (unsigned i = 0; i < dpm->nbp; i++) {
+ if (dpm->dbp[i].bp == bp) {
+ dpm->dbp[i].bp = NULL;
+ dpm->dbp[i].bpwp.dirty = true;
+
+ /* hardware is updated in write_dirty_registers() */
+ retval = ERROR_OK;
+ break;
+ }
+ }
+
+ return retval;
+}
+
+static int dpm_watchpoint_setup(struct arm_dpm *dpm, unsigned index,
+ struct watchpoint *wp)
+{
+ int retval;
+ struct dpm_wp *dwp = dpm->dwp + index;
+ uint32_t control;
+
+ /* this hardware doesn't support data value matching or masking */
+ if (wp->value || wp->mask != ~(uint32_t)0) {
+ LOG_DEBUG("watchpoint values and masking not supported");
+ return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+ }
+
+ retval = dpm_bpwp_setup(dpm, &dwp->bpwp, wp->address, wp->length);
+ if (retval != ERROR_OK)
+ return retval;
+
+ control = dwp->bpwp.control;
+ switch (wp->rw) {
+ case WPT_READ:
+ control |= 1 << 3;
+ break;
+ case WPT_WRITE:
+ control |= 2 << 3;
+ break;
+ case WPT_ACCESS:
+ control |= 3 << 3;
+ break;
+ }
+ dwp->bpwp.control = control;
+
+ dpm->dwp[index].wp = wp;
+
+ return retval;
+}
static int dpm_add_watchpoint(struct target *target, struct watchpoint *wp)
{
for (unsigned i = 0; i < dpm->nwp; i++) {
if (dpm->dwp[i].wp == wp) {
dpm->dwp[i].wp = NULL;
- dpm->dwp[i].dirty = true;
+ dpm->dwp[i].bpwp.dirty = true;
/* hardware is updated in write_dirty_registers() */
retval = ERROR_OK;
arm->mrc = dpm_mrc;
arm->mcr = dpm_mcr;
- /* breakpoint and watchpoint setup */
+ /* breakpoint setup -- optional until it works everywhere */
+ if (!target->type->add_breakpoint) {
+ target->type->add_breakpoint = dpm_add_breakpoint;
+ target->type->remove_breakpoint = dpm_remove_breakpoint;
+ }
+
+ /* watchpoint setup */
target->type->add_watchpoint = dpm_add_watchpoint;
target->type->remove_watchpoint = dpm_remove_watchpoint;
- /* FIXME add breakpoint support */
/* FIXME add vector catch support */
dpm->nbp = 1 + ((dpm->didr >> 24) & 0xf);
if (dpm->bpwp_disable) {
unsigned i;
- for (i = 0; i < dpm->nbp; i++)
+ for (i = 0; i < dpm->nbp; i++) {
+ dpm->dbp[i].bpwp.number = i;
(void) dpm->bpwp_disable(dpm, i);
- for (i = 0; i < dpm->nwp; i++)
+ }
+ for (i = 0; i < dpm->nwp; i++) {
+ dpm->dwp[i].bpwp.number = 16 + i;
(void) dpm->bpwp_disable(dpm, 16 + i);
+ }
} else
LOG_WARNING("%s: can't disable breakpoints and watchpoints",
target_name(dpm->arm->target));