+ /* Wait for last issued instruction to complete. */
+ retval = cortex_a_wait_instrcmpl(target, dscr, false);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Switch to non-blocking mode if not already in that mode. */
+ retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, dscr);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Check for faults and return early. */
+ if (*dscr & (DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE))
+ return ERROR_OK; /* A data fault is not considered a system failure. */
+
+ /* Wait until DTRTX is full (according to ARMv7-A/-R architecture manual
+ * section C8.4.3, checking InstrCmpl_l is not sufficient; one must also
+ * check TXfull_l). Most of the time this will be free because TXfull_l
+ * will be set immediately and cached in dscr. */
+ retval = cortex_a_wait_dscr_bits(target, DSCR_DTRTX_FULL_LATCHED,
+ DSCR_DTRTX_FULL_LATCHED, dscr);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Read the value transferred to DTRTX into the buffer. This is the last
+ * word. */
+ retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DTRTX, &u32);
+ if (retval != ERROR_OK)
+ return retval;
+ target_buffer_set_u32(target, buffer, u32);
+
+ return ERROR_OK;
+}
+
+static int cortex_a_read_cpu_memory(struct target *target,
+ uint32_t address, uint32_t size,
+ uint32_t count, uint8_t *buffer)
+{
+ /* Read memory through the CPU. */
+ int retval, final_retval;
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ struct arm *arm = &armv7a->arm;
+ uint32_t dscr, orig_dfar, orig_dfsr, fault_dscr, fault_dfar, fault_dfsr;
+
+ LOG_DEBUG("Reading CPU memory address 0x%" PRIx32 " size %" PRIu32 " count %" PRIu32,
+ address, size, count);
+ if (target->state != TARGET_HALTED) {
+ LOG_WARNING("target not halted");
+ return ERROR_TARGET_NOT_HALTED;
+ }
+
+ if (!count)
+ return ERROR_OK;
+
+ /* Clear any abort. */
+ retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DRCR, DRCR_CLEAR_EXCEPTIONS);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Read DSCR */
+ retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DSCR, &dscr);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Switch to non-blocking mode if not already in that mode. */
+ retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, &dscr);
+ if (retval != ERROR_OK)
+ goto out;
+
+ /* Mark R0 as dirty. */
+ arm_reg_current(arm, 0)->dirty = true;
+
+ /* Read DFAR and DFSR, as they will be modified in the event of a fault. */
+ retval = cortex_a_read_dfar_dfsr(target, &orig_dfar, &orig_dfsr, &dscr);
+ if (retval != ERROR_OK)
+ goto out;
+
+ /* Get the memory address into R0. */
+ retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DTRRX, address);
+ if (retval != ERROR_OK)
+ goto out;
+ retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 0, 0, 5, 0), &dscr);
+ if (retval != ERROR_OK)
+ goto out;
+
+ if (size == 4 && (address % 4) == 0) {
+ /* We are doing a word-aligned transfer, so use fast mode. */
+ retval = cortex_a_read_cpu_memory_fast(target, count, buffer, &dscr);
+ } else {
+ /* Use slow path. */
+ retval = cortex_a_read_cpu_memory_slow(target, size, count, buffer, &dscr);
+ }
+
+out:
+ final_retval = retval;
+
+ /* Switch to non-blocking mode if not already in that mode. */
+ retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, &dscr);
+ if (final_retval == ERROR_OK)
+ final_retval = retval;
+
+ /* Wait for last issued instruction to complete. */
+ retval = cortex_a_wait_instrcmpl(target, &dscr, true);
+ if (final_retval == ERROR_OK)
+ final_retval = retval;
+
+ /* If there were any sticky abort flags, clear them. */
+ if (dscr & (DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE)) {
+ fault_dscr = dscr;
+ mem_ap_write_atomic_u32(armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DRCR, DRCR_CLEAR_EXCEPTIONS);
+ dscr &= ~(DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE);
+ } else {
+ fault_dscr = 0;
+ }
+
+ /* Handle synchronous data faults. */
+ if (fault_dscr & DSCR_STICKY_ABORT_PRECISE) {
+ if (final_retval == ERROR_OK) {
+ /* Final return value will reflect cause of fault. */
+ retval = cortex_a_read_dfar_dfsr(target, &fault_dfar, &fault_dfsr, &dscr);
+ if (retval == ERROR_OK) {
+ LOG_ERROR("data abort at 0x%08" PRIx32 ", dfsr = 0x%08" PRIx32, fault_dfar, fault_dfsr);
+ final_retval = cortex_a_dfsr_to_error_code(fault_dfsr);
+ } else
+ final_retval = retval;