#include "armv4_5.h" /* REVISIT to become arm.h */
#include "arm_dpm.h"
-#include "jtag.h"
+#include <jtag/jtag.h>
#include "register.h"
+#include "breakpoints.h"
+#include "target_type.h"
/**
* implementation differences between cores like ARM1136 and Cortex-A8.
*/
+/*----------------------------------------------------------------------*/
+
/*
* Coprocessor support
*/
return retval;
}
+/*----------------------------------------------------------------------*/
+
/*
* Register access utilities
*/
switch (regnum) {
case 0 ... 14:
- /* load register from DCC: "MCR p14, 0, Rnum, c0, c5, 0" */
+ /* load register from DCC: "MRC p14, 0, Rnum, c0, c5, 0" */
retval = dpm->instr_write_data_dcc(dpm,
ARMV4_5_MRC(14, 0, regnum, 0, 5, 0),
value);
/* NOTE: SPSR ignored (if it's even relevant). */
+ /* REVISIT the debugger can trigger various exceptions. See the
+ * ARMv7A architecture spec, section C5.7, for more info about
+ * what defenses are needed; v6 debug has the most issues.
+ */
+
fail:
/* (void) */ dpm->finish(dpm);
return retval;
/**
* Writes all modified core registers for all processor modes. In normal
* operation this is called on exit from halting debug state.
+ *
+ * @param bpwp: true ensures breakpoints and watchpoints are set,
+ * false ensures they are cleared
*/
-int arm_dpm_write_dirty_registers(struct arm_dpm *dpm)
+int arm_dpm_write_dirty_registers(struct arm_dpm *dpm, bool bpwp)
{
struct arm *arm = dpm->arm;
struct reg_cache *cache = arm->core_cache;
if (retval != ERROR_OK)
goto done;
+ /* 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, dwp->control);
+
+ if (retval != ERROR_OK)
+ LOG_ERROR("%s: can't %s HW watchpoint %d",
+ target_name(arm->target),
+ disable ? "disable" : "enable",
+ i);
+ }
+
+ /* NOTE: writes to breakpoint and watchpoint registers might
+ * be queued, and need (efficient/batched) flushing later.
+ */
+
/* Scan the registers until we find one that's both dirty and
* eligible for flushing. Flush that and everything else that
* shares the same core mode setting. Typically this won't
return ARMV4_5_MODE_ANY;
}
+
+/*
+ * Standard ARM register accessors ... there are three methods
+ * in "struct arm", to support individual read/write and bulk read
+ * of registers.
+ */
+
static int arm_dpm_read_core_reg(struct target *target, struct reg *r,
int regnum, enum armv4_5_mode mode)
{
return retval;
}
+
+/*----------------------------------------------------------------------*/
+
+/*
+ * Breakpoint and Watchpoint support.
+ *
+ * Hardware {break,watch}points are usually left active, to minimize
+ * debug entry/exit costs. When they are set or cleared, it's done in
+ * batches. Also, DPM-conformant hardware can update debug registers
+ * regardless of whether the CPU is running or halted ... though that
+ * fact isn't currently leveraged.
+ */
+
+static int dpm_watchpoint_setup(struct arm_dpm *dpm, unsigned index,
+ struct watchpoint *wp)
+{
+ 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.
+ */
+ switch (wp->length) {
+ case 1:
+ control |= (1 << (addr & 3)) << 5;
+ addr &= ~3;
+ break;
+ case 2:
+ /* require 2-byte alignment */
+ if (!(addr & 1)) {
+ control |= (3 << (addr & 2)) << 5;
+ break;
+ }
+ /* FALL THROUGH */
+ case 4:
+ /* require 4-byte alignment */
+ if (!(addr & 3)) {
+ control |= 0xf << 5;
+ break;
+ }
+ /* FALL THROUGH */
+ default:
+ LOG_DEBUG("bad watchpoint length or alignment");
+ return ERROR_INVALID_ARGUMENTS;
+ }
+
+ /* other control bits:
+ * bits 9:12 == 0 ... only checking up to four byte addresses (v7 only)
+ * 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;
+
+ /* hardware is updated in write_dirty_registers() */
+ return ERROR_OK;
+}
+
+
+static int dpm_add_watchpoint(struct target *target, struct watchpoint *wp)
+{
+ struct arm *arm = target_to_arm(target);
+ struct arm_dpm *dpm = arm->dpm;
+ int retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+
+ if (dpm->bpwp_enable) {
+ for (unsigned i = 0; i < dpm->nwp; i++) {
+ if (!dpm->dwp[i].wp) {
+ retval = dpm_watchpoint_setup(dpm, i, wp);
+ break;
+ }
+ }
+ }
+
+ return retval;
+}
+
+static int dpm_remove_watchpoint(struct target *target, struct watchpoint *wp)
+{
+ struct arm *arm = target_to_arm(target);
+ struct arm_dpm *dpm = arm->dpm;
+ int retval = ERROR_INVALID_ARGUMENTS;
+
+ for (unsigned i = 0; i < dpm->nwp; i++) {
+ if (dpm->dwp[i].wp == wp) {
+ dpm->dwp[i].wp = NULL;
+ dpm->dwp[i].dirty = true;
+
+ /* hardware is updated in write_dirty_registers() */
+ retval = ERROR_OK;
+ break;
+ }
+ }
+
+ return retval;
+}
+
+void arm_dpm_report_wfar(struct arm_dpm *dpm, uint32_t addr)
+{
+ switch (dpm->arm->core_state) {
+ case ARMV4_5_STATE_ARM:
+ addr -= 8;
+ break;
+ case ARMV4_5_STATE_THUMB:
+ case ARM_STATE_THUMB_EE:
+ addr -= 4;
+ break;
+ case ARMV4_5_STATE_JAZELLE:
+ /* ?? */
+ break;
+ }
+ dpm->wp_pc = addr;
+}
+
+/*----------------------------------------------------------------------*/
+
+/*
+ * Other debug and support utilities
+ */
+
+void arm_dpm_report_dscr(struct arm_dpm *dpm, uint32_t dscr)
+{
+ struct target *target = dpm->arm->target;
+
+ dpm->dscr = dscr;
+
+ /* Examine debug reason */
+ switch (DSCR_ENTRY(dscr)) {
+ case 6: /* Data abort (v6 only) */
+ case 7: /* Prefetch abort (v6 only) */
+ /* FALL THROUGH -- assume a v6 core in abort mode */
+ case 0: /* HALT request from debugger */
+ case 4: /* EDBGRQ */
+ target->debug_reason = DBG_REASON_DBGRQ;
+ break;
+ case 1: /* HW breakpoint */
+ case 3: /* SW BKPT */
+ case 5: /* vector catch */
+ target->debug_reason = DBG_REASON_BREAKPOINT;
+ break;
+ case 2: /* asynch watchpoint */
+ case 10: /* precise watchpoint */
+ target->debug_reason = DBG_REASON_WATCHPOINT;
+ break;
+ default:
+ target->debug_reason = DBG_REASON_UNDEFINED;
+ break;
+ }
+}
+
+/*----------------------------------------------------------------------*/
+
+/*
+ * Setup and management support.
+ */
+
/**
* Hooks up this DPM to its associated target; call only once.
* Initially this only covers the register cache.
+ *
+ * Oh, and watchpoints. Yeah.
*/
int arm_dpm_setup(struct arm_dpm *dpm)
{
arm->dpm = dpm;
+ /* register access setup */
arm->full_context = arm_dpm_full_context;
arm->read_core_reg = arm_dpm_read_core_reg;
arm->write_core_reg = arm_dpm_write_core_reg;
*register_get_last_cache_p(&target->reg_cache) = cache;
+ /* coprocessor access setup */
arm->mrc = dpm_mrc;
arm->mcr = dpm_mcr;
+ /* breakpoint and 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);
+ dpm->dbp = calloc(dpm->nbp, sizeof *dpm->dbp);
+
+ dpm->nwp = 1 + ((dpm->didr >> 28) & 0xf);
+ dpm->dwp = calloc(dpm->nwp, sizeof *dpm->dwp);
+
+ if (!dpm->dbp || !dpm->dwp) {
+ free(dpm->dbp);
+ free(dpm->dwp);
+ return ERROR_FAIL;
+ }
+
+ LOG_INFO("%s: hardware has %d breakpoints, %d watchpoints",
+ target_name(target), dpm->nbp, dpm->nwp);
+
+ /* REVISIT ... and some of those breakpoints could match
+ * execution context IDs...
+ */
+
return ERROR_OK;
}
*/
int arm_dpm_initialize(struct arm_dpm *dpm)
{
- /* FIXME -- nothing yet */
+ /* Disable all breakpoints and watchpoints at startup. */
+ if (dpm->bpwp_disable) {
+ unsigned i;
+
+ for (i = 0; i < dpm->nbp; i++)
+ (void) dpm->bpwp_disable(dpm, i);
+ for (i = 0; i < dpm->nwp; i++)
+ (void) dpm->bpwp_disable(dpm, 16 + i);
+ } else
+ LOG_WARNING("%s: can't disable breakpoints and watchpoints",
+ target_name(dpm->arm->target));
+
return ERROR_OK;
}
projects / fw / openocd / blobdiff