return cortex_a_poll(target);
}
+static int cortex_a_wait_instrcmpl(struct target *target, uint32_t *dscr, bool force)
+{
+ /* Waits until InstrCmpl_l becomes 1, indicating instruction is done.
+ * Writes final value of DSCR into *dscr. Pass force to force always
+ * reading DSCR at least once. */
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ struct adiv5_dap *swjdp = armv7a->arm.dap;
+ long long then = timeval_ms();
+ while ((*dscr & DSCR_INSTR_COMP) == 0 || force) {
+ force = false;
+ int retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DSCR, dscr);
+ if (retval != ERROR_OK) {
+ LOG_ERROR("Could not read DSCR register");
+ return retval;
+ }
+ if (timeval_ms() > then + 1000) {
+ LOG_ERROR("Timeout waiting for InstrCompl=1");
+ return ERROR_FAIL;
+ }
+ }
+ return ERROR_OK;
+}
+
/* To reduce needless round-trips, pass in a pointer to the current
* DSCR value. Initialize it to zero if you just need to know the
* value on return from this function; or DSCR_INSTR_COMP if you
LOG_DEBUG("exec opcode 0x%08" PRIx32, opcode);
/* Wait for InstrCompl bit to be set */
- long long then = timeval_ms();
- while ((dscr & DSCR_INSTR_COMP) == 0) {
- retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, &dscr);
- if (retval != ERROR_OK) {
- LOG_ERROR("Could not read DSCR register, opcode = 0x%08" PRIx32, opcode);
- return retval;
- }
- if (timeval_ms() > then + 1000) {
- LOG_ERROR("Timeout waiting for cortex_a_exec_opcode");
- return ERROR_FAIL;
- }
- }
+ retval = cortex_a_wait_instrcmpl(target, dscr_p, false);
+ if (retval != ERROR_OK)
+ return retval;
retval = mem_ap_sel_write_u32(swjdp, armv7a->debug_ap,
armv7a->debug_base + CPUDBG_ITR, opcode);
if (retval != ERROR_OK)
return retval;
- then = timeval_ms();
+ long long then = timeval_ms();
do {
retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
armv7a->debug_base + CPUDBG_DSCR, &dscr);
return ERROR_OK;
}
-static int cortex_a_write_apb_ab_memory(struct target *target,
- uint32_t address, uint32_t size,
- uint32_t count, const uint8_t *buffer)
+static int cortex_a_set_dcc_mode(struct target *target, uint32_t mode, uint32_t *dscr)
{
- /* write memory through APB-AP */
+ /* Changes the mode of the DCC between non-blocking, stall, and fast mode.
+ * New desired mode must be in mode. Current value of DSCR must be in
+ * *dscr, which is updated with new value.
+ *
+ * This function elides actually sending the mode-change over the debug
+ * interface if the mode is already set as desired.
+ */
+ uint32_t new_dscr = (*dscr & ~DSCR_EXT_DCC_MASK) | mode;
+ if (new_dscr != *dscr) {
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ int retval = mem_ap_sel_write_atomic_u32(armv7a->arm.dap,
+ armv7a->debug_ap, armv7a->debug_base + CPUDBG_DSCR, new_dscr);
+ if (retval == ERROR_OK)
+ *dscr = new_dscr;
+ return retval;
+ } else {
+ return ERROR_OK;
+ }
+}
- int retval = ERROR_COMMAND_SYNTAX_ERROR;
+static int cortex_a_wait_dscr_bits(struct target *target, uint32_t mask,
+ uint32_t value, uint32_t *dscr)
+{
+ /* Waits until the specified bit(s) of DSCR take on a specified value. */
struct armv7a_common *armv7a = target_to_armv7a(target);
- struct arm *arm = &armv7a->arm;
struct adiv5_dap *swjdp = armv7a->arm.dap;
- int total_bytes = count * size;
- int total_u32;
- int start_byte = address & 0x3;
- int end_byte = (address + total_bytes) & 0x3;
- struct reg *reg;
- uint32_t dscr;
- uint8_t *tmp_buff = NULL;
-
+ long long then = timeval_ms();
+ int retval;
- LOG_DEBUG("Writing APB-AP 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;
+ while ((*dscr & mask) != value) {
+ retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DSCR, dscr);
+ if (retval != ERROR_OK)
+ return retval;
+ if (timeval_ms() > then + 1000) {
+ LOG_ERROR("timeout waiting for DSCR bit change");
+ return ERROR_FAIL;
+ }
}
+ return ERROR_OK;
+}
- total_u32 = DIV_ROUND_UP((address & 3) + total_bytes, 4);
+static int cortex_a_read_copro(struct target *target, uint32_t opcode,
+ uint32_t *data, uint32_t *dscr)
+{
+ int retval;
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ struct adiv5_dap *swjdp = armv7a->arm.dap;
- /* Mark register R0 as dirty, as it will be used
- * for transferring the data.
- * It will be restored automatically when exiting
- * debug mode
- */
- reg = arm_reg_current(arm, 0);
- reg->dirty = true;
+ /* Move from coprocessor to R0. */
+ retval = cortex_a_exec_opcode(target, opcode, dscr);
+ if (retval != ERROR_OK)
+ return retval;
- /* clear any abort */
- retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap, armv7a->debug_base + CPUDBG_DRCR, 1<<2);
+ /* Move from R0 to DTRTX. */
+ retval = cortex_a_exec_opcode(target, ARMV4_5_MCR(14, 0, 0, 0, 5, 0), dscr);
if (retval != ERROR_OK)
return retval;
- /* This algorithm comes from either :
- * Cortex-A TRM Example 12-25
- * Cortex-R4 TRM Example 11-26
- * (slight differences)
- */
+ /* 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;
- /* The algorithm only copies 32 bit words, so the buffer
- * should be expanded to include the words at either end.
- * The first and last words will be read first to avoid
- * corruption if needed.
- */
- tmp_buff = malloc(total_u32 * 4);
+ /* Read the value transferred to DTRTX. */
+ retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DTRTX, data);
+ if (retval != ERROR_OK)
+ return retval;
- if ((start_byte != 0) && (total_u32 > 1)) {
- /* First bytes not aligned - read the 32 bit word to avoid corrupting
- * the other bytes in the word.
- */
- retval = cortex_a_read_apb_ab_memory(target, (address & ~0x3), 4, 1, tmp_buff);
+ return ERROR_OK;
+}
+
+static int cortex_a_read_dfar_dfsr(struct target *target, uint32_t *dfar,
+ uint32_t *dfsr, uint32_t *dscr)
+{
+ int retval;
+
+ if (dfar) {
+ retval = cortex_a_read_copro(target, ARMV4_5_MRC(15, 0, 0, 6, 0, 0), dfar, dscr);
if (retval != ERROR_OK)
- goto error_free_buff_w;
+ return retval;
}
- /* If end of write is not aligned, or the write is less than 4 bytes */
- if ((end_byte != 0) ||
- ((total_u32 == 1) && (total_bytes != 4))) {
- /* Read the last word to avoid corruption during 32 bit write */
- int mem_offset = (total_u32-1) * 4;
- retval = cortex_a_read_apb_ab_memory(target, (address & ~0x3) + mem_offset, 4, 1, &tmp_buff[mem_offset]);
+ if (dfsr) {
+ retval = cortex_a_read_copro(target, ARMV4_5_MRC(15, 0, 0, 5, 0, 0), dfsr, dscr);
if (retval != ERROR_OK)
- goto error_free_buff_w;
+ return retval;
}
- /* Copy the write buffer over the top of the temporary buffer */
- memcpy(&tmp_buff[start_byte], buffer, total_bytes);
+ return ERROR_OK;
+}
- /* We now have a 32 bit aligned buffer that can be written */
+static int cortex_a_write_copro(struct target *target, uint32_t opcode,
+ uint32_t data, uint32_t *dscr)
+{
+ int retval;
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ struct adiv5_dap *swjdp = armv7a->arm.dap;
- /* Read DSCR */
- retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, &dscr);
+ /* Write the value into DTRRX. */
+ retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DTRRX, data);
if (retval != ERROR_OK)
- goto error_free_buff_w;
+ return retval;
- /* Set DTR mode to Fast (2) */
- dscr = (dscr & ~DSCR_EXT_DCC_MASK) | DSCR_EXT_DCC_FAST_MODE;
- retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, dscr);
+ /* Move from DTRRX to R0. */
+ retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 0, 0, 5, 0), dscr);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Move from R0 to coprocessor. */
+ retval = cortex_a_exec_opcode(target, opcode, dscr);
if (retval != ERROR_OK)
- goto error_free_buff_w;
+ return retval;
- /* Copy the destination address into R0 */
- /* - pend an instruction MRC p14, 0, R0, c5, c0 */
- retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_ITR, ARMV4_5_MRC(14, 0, 0, 0, 5, 0));
+ /* Wait until DTRRX is empty (according to ARMv7-A/-R architecture manual
+ * section C8.4.3, checking InstrCmpl_l is not sufficient; one must also
+ * check RXfull_l). Most of the time this will be free because RXfull_l
+ * will be cleared immediately and cached in dscr. */
+ retval = cortex_a_wait_dscr_bits(target, DSCR_DTRRX_FULL_LATCHED, 0, dscr);
if (retval != ERROR_OK)
- goto error_unset_dtr_w;
- /* Write address into DTRRX, which triggers previous instruction */
- retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DTRRX, address & (~0x3));
+ return retval;
+
+ return ERROR_OK;
+}
+
+static int cortex_a_write_dfar_dfsr(struct target *target, uint32_t dfar,
+ uint32_t dfsr, uint32_t *dscr)
+{
+ int retval;
+
+ retval = cortex_a_write_copro(target, ARMV4_5_MCR(15, 0, 0, 6, 0, 0), dfar, dscr);
if (retval != ERROR_OK)
- goto error_unset_dtr_w;
+ return retval;
- /* Write the data transfer instruction into the ITR
- * (STC p14, c5, [R0], 4)
+ retval = cortex_a_write_copro(target, ARMV4_5_MCR(15, 0, 0, 5, 0, 0), dfsr, dscr);
+ if (retval != ERROR_OK)
+ return retval;
+
+ return ERROR_OK;
+}
+
+static int cortex_a_dfsr_to_error_code(uint32_t dfsr)
+{
+ uint32_t status, upper4;
+
+ if (dfsr & (1 << 9)) {
+ /* LPAE format. */
+ status = dfsr & 0x3f;
+ upper4 = status >> 2;
+ if (upper4 == 1 || upper4 == 2 || upper4 == 3 || upper4 == 15)
+ return ERROR_TARGET_TRANSLATION_FAULT;
+ else if (status == 33)
+ return ERROR_TARGET_UNALIGNED_ACCESS;
+ else
+ return ERROR_TARGET_DATA_ABORT;
+ } else {
+ /* Normal format. */
+ status = ((dfsr >> 6) & 0x10) | (dfsr & 0xf);
+ if (status == 1)
+ return ERROR_TARGET_UNALIGNED_ACCESS;
+ else if (status == 5 || status == 7 || status == 3 || status == 6 ||
+ status == 9 || status == 11 || status == 13 || status == 15)
+ return ERROR_TARGET_TRANSLATION_FAULT;
+ else
+ return ERROR_TARGET_DATA_ABORT;
+ }
+}
+
+static int cortex_a_write_apb_ab_memory_slow(struct target *target,
+ uint32_t size, uint32_t count, const uint8_t *buffer, uint32_t *dscr)
+{
+ /* Writes count objects of size size from *buffer. Old value of DSCR must
+ * be in *dscr; updated to new value. This is slow because it works for
+ * non-word-sized objects and (maybe) unaligned accesses. If size == 4 and
+ * the address is aligned, cortex_a_write_apb_ab_memory_fast should be
+ * preferred.
+ * Preconditions:
+ * - Address is in R0.
+ * - R0 is marked dirty.
*/
- retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_ITR, ARMV4_5_STC(0, 1, 0, 1, 14, 5, 0, 4));
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ struct adiv5_dap *swjdp = armv7a->arm.dap;
+ struct arm *arm = &armv7a->arm;
+ int retval;
+
+ /* Mark register R1 as dirty, to use for transferring data. */
+ arm_reg_current(arm, 1)->dirty = true;
+
+ /* 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 error_unset_dtr_w;
+ return retval;
- /* Do the write */
- retval = mem_ap_sel_write_buf_noincr(swjdp, armv7a->debug_ap,
- tmp_buff, 4, total_u32, armv7a->debug_base + CPUDBG_DTRRX);
+ /* Go through the objects. */
+ while (count) {
+ /* Write the value to store into DTRRX. */
+ uint32_t data, opcode;
+ if (size == 1)
+ data = *buffer;
+ else if (size == 2)
+ data = target_buffer_get_u16(target, buffer);
+ else
+ data = target_buffer_get_u32(target, buffer);
+ retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DTRRX, data);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Transfer the value from DTRRX to R1. */
+ retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 1, 0, 5, 0), dscr);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Write the value transferred to R1 into memory. */
+ if (size == 1)
+ opcode = ARMV4_5_STRB_IP(1, 0);
+ else if (size == 2)
+ opcode = ARMV4_5_STRH_IP(1, 0);
+ else
+ opcode = ARMV4_5_STRW_IP(1, 0);
+ retval = cortex_a_exec_opcode(target, opcode, 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 DTRRX is empty (according to ARMv7-A/-R architecture
+ * manual section C8.4.3, checking InstrCmpl_l is not sufficient; one
+ * must also check RXfull_l). Most of the time this will be free
+ * because RXfull_l will be cleared immediately and cached in dscr. */
+ retval = cortex_a_wait_dscr_bits(target, DSCR_DTRRX_FULL_LATCHED, 0, dscr);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Advance. */
+ buffer += size;
+ --count;
+ }
+
+ return ERROR_OK;
+}
+
+static int cortex_a_write_apb_ab_memory_fast(struct target *target,
+ uint32_t count, const uint8_t *buffer, uint32_t *dscr)
+{
+ /* Writes count objects of size 4 from *buffer. Old value of DSCR must be
+ * in *dscr; updated to new value. This is fast but only works for
+ * word-sized objects at aligned addresses.
+ * Preconditions:
+ * - Address is in R0 and must be a multiple of 4.
+ * - R0 is marked dirty.
+ */
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ struct adiv5_dap *swjdp = armv7a->arm.dap;
+ int retval;
+
+ /* Switch to fast mode if not already in that mode. */
+ retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_FAST_MODE, dscr);
if (retval != ERROR_OK)
- goto error_unset_dtr_w;
+ return retval;
+ /* Latch STC instruction. */
+ retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_ITR, ARMV4_5_STC(0, 1, 0, 1, 14, 5, 0, 4));
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Transfer all the data and issue all the instructions. */
+ return mem_ap_sel_write_buf_noincr(swjdp, armv7a->debug_ap, buffer,
+ 4, count, armv7a->debug_base + CPUDBG_DTRRX);
+}
+
+static int cortex_a_write_apb_ab_memory(struct target *target,
+ uint32_t address, uint32_t size,
+ uint32_t count, const uint8_t *buffer)
+{
+ /* Write memory through APB-AP. */
+ int retval, final_retval;
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ struct adiv5_dap *swjdp = armv7a->arm.dap;
+ struct arm *arm = &armv7a->arm;
+ uint32_t dscr, orig_dfar, orig_dfsr, fault_dscr, fault_dfar, fault_dfsr;
- /* Switch DTR mode back to non-blocking (0) */
- dscr = (dscr & ~DSCR_EXT_DCC_MASK) | DSCR_EXT_DCC_NON_BLOCKING;
+ LOG_DEBUG("Writing APB-AP 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_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, dscr);
+ armv7a->debug_base + CPUDBG_DRCR, DRCR_CLEAR_EXCEPTIONS);
if (retval != ERROR_OK)
- goto error_unset_dtr_w;
+ return retval;
- /* Check for sticky abort flags in the DSCR */
+ /* Read DSCR. */
retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, &dscr);
+ 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_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DTRRX, address);
if (retval != ERROR_OK)
- goto error_free_buff_w;
+ 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_write_apb_ab_memory_fast(target, count, buffer, &dscr);
+ } else {
+ /* Use slow path. */
+ retval = cortex_a_write_apb_ab_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;
+
+ /* Wait until DTRRX is empty (according to ARMv7-A/-R architecture manual
+ * section C8.4.3, checking InstrCmpl_l is not sufficient; one must also
+ * check RXfull_l). Most of the time this will be free because RXfull_l
+ * will be cleared immediately and cached in dscr. However, don’t do this
+ * if there is fault, because then the instruction might not have completed
+ * successfully. */
+ if (!(dscr & DSCR_STICKY_ABORT_PRECISE)) {
+ retval = cortex_a_wait_dscr_bits(target, DSCR_DTRRX_FULL_LATCHED, 0, &dscr);
+ if (retval != ERROR_OK)
+ return retval;
+ }
+
+ /* If there were any sticky abort flags, clear them. */
if (dscr & (DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE)) {
- /* Abort occurred - clear it and exit */
- LOG_ERROR("abort occurred - dscr = 0x%08" PRIx32, dscr);
+ fault_dscr = dscr;
mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DRCR, 1<<2);
- goto error_free_buff_w;
+ 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;
+ }
+ /* Fault destroyed DFAR/DFSR; restore them. */
+ retval = cortex_a_write_dfar_dfsr(target, orig_dfar, orig_dfsr, &dscr);
+ if (retval != ERROR_OK)
+ LOG_ERROR("error restoring dfar/dfsr - dscr = 0x%08" PRIx32, dscr);
+ }
+
+ /* Handle asynchronous data faults. */
+ if (fault_dscr & DSCR_STICKY_ABORT_IMPRECISE) {
+ if (final_retval == ERROR_OK)
+ /* No other error has been recorded so far, so keep this one. */
+ final_retval = ERROR_TARGET_DATA_ABORT;
+ }
+
+ /* If the DCC is nonempty, clear it. */
+ if (dscr & DSCR_DTRTX_FULL_LATCHED) {
+ uint32_t dummy;
+ retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DTRTX, &dummy);
+ if (final_retval == ERROR_OK)
+ final_retval = retval;
+ }
+ if (dscr & DSCR_DTRRX_FULL_LATCHED) {
+ retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 1, 0, 5, 0), &dscr);
+ if (final_retval == ERROR_OK)
+ final_retval = retval;
+ }
+
+ /* Done. */
+ return final_retval;
+}
+
+static int cortex_a_read_apb_ab_memory_slow(struct target *target,
+ uint32_t size, uint32_t count, uint8_t *buffer, uint32_t *dscr)
+{
+ /* Reads count objects of size size into *buffer. Old value of DSCR must be
+ * in *dscr; updated to new value. This is slow because it works for
+ * non-word-sized objects and (maybe) unaligned accesses. If size == 4 and
+ * the address is aligned, cortex_a_read_apb_ab_memory_fast should be
+ * preferred.
+ * Preconditions:
+ * - Address is in R0.
+ * - R0 is marked dirty.
+ */
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ struct adiv5_dap *swjdp = armv7a->arm.dap;
+ struct arm *arm = &armv7a->arm;
+ int retval;
+
+ /* Mark register R1 as dirty, to use for transferring data. */
+ arm_reg_current(arm, 1)->dirty = true;
+
+ /* 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;
+
+ /* Go through the objects. */
+ while (count) {
+ /* Issue a load of the appropriate size to R1. */
+ uint32_t opcode, data;
+ if (size == 1)
+ opcode = ARMV4_5_LDRB_IP(1, 0);
+ else if (size == 2)
+ opcode = ARMV4_5_LDRH_IP(1, 0);
+ else
+ opcode = ARMV4_5_LDRW_IP(1, 0);
+ retval = cortex_a_exec_opcode(target, opcode, dscr);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Issue a write of R1 to DTRTX. */
+ retval = cortex_a_exec_opcode(target, ARMV4_5_MCR(14, 0, 1, 0, 5, 0), 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. */
+ retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DTRTX, &data);
+ if (retval != ERROR_OK)
+ return retval;
+ if (size == 1)
+ *buffer = (uint8_t) data;
+ else if (size == 2)
+ target_buffer_set_u16(target, buffer, (uint16_t) data);
+ else
+ target_buffer_set_u32(target, buffer, data);
+
+ /* Advance. */
+ buffer += size;
+ --count;
}
- /* Done */
- free(tmp_buff);
return ERROR_OK;
+}
-error_unset_dtr_w:
- /* Unset DTR mode */
- mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, &dscr);
- dscr = (dscr & ~DSCR_EXT_DCC_MASK) | DSCR_EXT_DCC_NON_BLOCKING;
- mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, dscr);
-error_free_buff_w:
- LOG_ERROR("error");
- free(tmp_buff);
- return ERROR_FAIL;
+static int cortex_a_read_apb_ab_memory_fast(struct target *target,
+ uint32_t count, uint8_t *buffer, uint32_t *dscr)
+{
+ /* Reads count objects of size 4 into *buffer. Old value of DSCR must be in
+ * *dscr; updated to new value. This is fast but only works for word-sized
+ * objects at aligned addresses.
+ * Preconditions:
+ * - Address is in R0 and must be a multiple of 4.
+ * - R0 is marked dirty.
+ */
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ struct adiv5_dap *swjdp = armv7a->arm.dap;
+ uint32_t new_dscr, u32;
+ int 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;
+
+ if (count > 1) {
+ /* Consecutively issue the LDC instruction via a write to ITR and
+ * change to fast mode, in a single bulk copy since DSCR == ITR + 4.
+ * The instruction is issued into the core before the mode switch. */
+ uint8_t command[8];
+ target_buffer_set_u32(target, command, ARMV4_5_LDC(0, 1, 0, 1, 14, 5, 0, 4));
+ new_dscr = (*dscr & ~DSCR_EXT_DCC_MASK) | DSCR_EXT_DCC_FAST_MODE;
+ target_buffer_set_u32(target, command + 4, new_dscr);
+ retval = mem_ap_sel_write_buf(swjdp, armv7a->debug_ap, command, 4, 2,
+ armv7a->debug_base + CPUDBG_ITR);
+ if (retval != ERROR_OK)
+ return retval;
+ *dscr = new_dscr;
+
+ /* Read the value transferred to DTRTX into the buffer. Due to fast
+ * mode rules, this blocks until the instruction finishes executing and
+ * then reissues the read instruction to read the next word from
+ * memory. The last read of DTRTX in this call reads the second-to-last
+ * word from memory and issues the read instruction for the last word.
+ */
+ retval = mem_ap_sel_read_buf_noincr(swjdp, armv7a->debug_ap, buffer,
+ 4, count - 1, armv7a->debug_base + CPUDBG_DTRTX);
+ if (retval != ERROR_OK)
+ return retval;
+
+ /* Advance. */
+ buffer += (count - 1) * 4;
+ count = 1;
+ } else {
+ /* Issue the LDC instruction via a write to ITR. */
+ retval = cortex_a_exec_opcode(target, ARMV4_5_LDC(0, 1, 0, 1, 14, 5, 0, 4), 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)
+ return retval;
+
+ /* Wait for last issued instruction to complete. */
+ retval = cortex_a_wait_instrcmpl(target, dscr, false);
+ 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_sel_read_atomic_u32(swjdp, 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_apb_ab_memory(struct target *target,
uint32_t address, uint32_t size,
uint32_t count, uint8_t *buffer)
{
- /* read memory through APB-AP */
-
- int retval = ERROR_COMMAND_SYNTAX_ERROR;
+ /* Read memory through APB-AP. */
+ int retval, final_retval;
struct armv7a_common *armv7a = target_to_armv7a(target);
struct adiv5_dap *swjdp = armv7a->arm.dap;
struct arm *arm = &armv7a->arm;
- int total_bytes = count * size;
- int total_u32;
- int start_byte = address & 0x3;
- int end_byte = (address + total_bytes) & 0x3;
- struct reg *reg;
- uint32_t dscr;
- uint8_t *tmp_buff = NULL;
- uint8_t buf[8];
- uint8_t *u8buf_ptr;
+ uint32_t dscr, orig_dfar, orig_dfsr, fault_dscr, fault_dfar, fault_dfsr;
- LOG_DEBUG("Reading APB-AP memory address 0x%" PRIx32 " size %" PRIu32 " count%" PRIu32,
+ LOG_DEBUG("Reading APB-AP 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;
}
- total_u32 = DIV_ROUND_UP((address & 3) + total_bytes, 4);
- /* Mark register R0 as dirty, as it will be used
- * for transferring the data.
- * It will be restored automatically when exiting
- * debug mode
- */
- reg = arm_reg_current(arm, 0);
- reg->dirty = true;
+ if (!count)
+ return ERROR_OK;
- /* clear any abort */
- retval =
- mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap, armv7a->debug_base + CPUDBG_DRCR, 1<<2);
+ /* Clear any abort. */
+ retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DRCR, DRCR_CLEAR_EXCEPTIONS);
if (retval != ERROR_OK)
- goto error_free_buff_r;
+ return retval;
/* Read DSCR */
retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
armv7a->debug_base + CPUDBG_DSCR, &dscr);
+ if (retval != ERROR_OK)
+ return retval;
- /* This algorithm comes from either :
- * Cortex-A TRM Example 12-24
- * Cortex-R4 TRM Example 11-25
- * (slight differences)
- */
+ /* 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;
- /* Set DTR access mode to stall mode b01 */
- dscr = (dscr & ~DSCR_EXT_DCC_MASK) | DSCR_EXT_DCC_STALL_MODE;
- retval += mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, dscr);
+ /* Mark R0 as dirty. */
+ arm_reg_current(arm, 0)->dirty = true;
- /* Write R0 with value 'address' using write procedure for stall mode */
- /* - Write the address for read access into DTRRX */
- retval += mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DTRRX, address & ~0x3);
- /* - Copy value from DTRRX to R0 using instruction mrc p14, 0, r0, c5, c0 */
- cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 0, 0, 5, 0), &dscr);
+ /* 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;
- /* Write the data transfer instruction (ldc p14, c5, [r0],4)
- * and the DTR mode setting to fast mode
- * in one combined write (since they are adjacent registers)
- */
- u8buf_ptr = buf;
- target_buffer_set_u32(target, u8buf_ptr, ARMV4_5_LDC(0, 1, 0, 1, 14, 5, 0, 4));
- dscr = (dscr & ~DSCR_EXT_DCC_MASK) | DSCR_EXT_DCC_FAST_MODE;
- target_buffer_set_u32(target, u8buf_ptr + 4, dscr);
- /* group the 2 access CPUDBG_ITR 0x84 and CPUDBG_DSCR 0x88 */
- retval += mem_ap_sel_write_buf(swjdp, armv7a->debug_ap, u8buf_ptr, 4, 2,
- armv7a->debug_base + CPUDBG_ITR);
- if (retval != ERROR_OK)
- goto error_unset_dtr_r;
-
- /* Optimize the read as much as we can, either way we read in a single pass */
- if ((start_byte) || (end_byte)) {
- /* The algorithm only copies 32 bit words, so the buffer
- * should be expanded to include the words at either end.
- * The first and last words will be read into a temp buffer
- * to avoid corruption
- */
- tmp_buff = malloc(total_u32 * 4);
- if (!tmp_buff)
- goto error_unset_dtr_r;
+ /* Get the memory address into R0. */
+ retval = mem_ap_sel_write_atomic_u32(swjdp, 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;
- /* use the tmp buffer to read the entire data */
- u8buf_ptr = tmp_buff;
- } else
- /* address and read length are aligned so read directely into the passed buffer */
- u8buf_ptr = buffer;
+ if (size == 4 && (address % 4) == 0) {
+ /* We are doing a word-aligned transfer, so use fast mode. */
+ retval = cortex_a_read_apb_ab_memory_fast(target, count, buffer, &dscr);
+ } else {
+ /* Use slow path. */
+ retval = cortex_a_read_apb_ab_memory_slow(target, size, count, buffer, &dscr);
+ }
- /* Read the data - Each read of the DTRTX register causes the instruction to be reissued
- * Abort flags are sticky, so can be read at end of transactions
- *
- * This data is read in aligned to 32 bit boundary.
- */
- retval = mem_ap_sel_read_buf_noincr(swjdp, armv7a->debug_ap, u8buf_ptr, 4, total_u32,
- armv7a->debug_base + CPUDBG_DTRTX);
- if (retval != ERROR_OK)
- goto error_unset_dtr_r;
+out:
+ final_retval = retval;
- /* set DTR access mode back to non blocking b00 */
- dscr = (dscr & ~DSCR_EXT_DCC_MASK) | DSCR_EXT_DCC_NON_BLOCKING;
- retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, dscr);
- if (retval != ERROR_OK)
- goto error_free_buff_r;
+ /* 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 the final read instruction to finish */
- do {
- retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, &dscr);
- if (retval != ERROR_OK)
- goto error_free_buff_r;
- } while ((dscr & DSCR_INSTR_COMP) == 0);
+ /* Wait for last issued instruction to complete. */
+ retval = cortex_a_wait_instrcmpl(target, &dscr, true);
+ if (final_retval == ERROR_OK)
+ final_retval = retval;
- /* Check for sticky abort flags in the DSCR */
- retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, &dscr);
- if (retval != ERROR_OK)
- goto error_free_buff_r;
+ /* If there were any sticky abort flags, clear them. */
if (dscr & (DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE)) {
- /* Abort occurred - clear it and exit */
- LOG_ERROR("abort occurred - dscr = 0x%08" PRIx32, dscr);
+ fault_dscr = dscr;
mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DRCR, 1<<2);
- goto error_free_buff_r;
+ 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;
+ }
+ /* Fault destroyed DFAR/DFSR; restore them. */
+ retval = cortex_a_write_dfar_dfsr(target, orig_dfar, orig_dfsr, &dscr);
+ if (retval != ERROR_OK)
+ LOG_ERROR("error restoring dfar/dfsr - dscr = 0x%08" PRIx32, dscr);
}
- /* check if we need to copy aligned data by applying any shift necessary */
- if (tmp_buff) {
- memcpy(buffer, tmp_buff + start_byte, total_bytes);
- free(tmp_buff);
+ /* Handle asynchronous data faults. */
+ if (fault_dscr & DSCR_STICKY_ABORT_IMPRECISE) {
+ if (final_retval == ERROR_OK)
+ /* No other error has been recorded so far, so keep this one. */
+ final_retval = ERROR_TARGET_DATA_ABORT;
}
- /* Done */
- return ERROR_OK;
+ /* If the DCC is nonempty, clear it. */
+ if (dscr & DSCR_DTRTX_FULL_LATCHED) {
+ uint32_t dummy;
+ retval = mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
+ armv7a->debug_base + CPUDBG_DTRTX, &dummy);
+ if (final_retval == ERROR_OK)
+ final_retval = retval;
+ }
+ if (dscr & DSCR_DTRRX_FULL_LATCHED) {
+ retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 1, 0, 5, 0), &dscr);
+ if (final_retval == ERROR_OK)
+ final_retval = retval;
+ }
-error_unset_dtr_r:
- /* Unset DTR mode */
- mem_ap_sel_read_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, &dscr);
- dscr = (dscr & ~DSCR_EXT_DCC_MASK) | DSCR_EXT_DCC_NON_BLOCKING;
- mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap,
- armv7a->debug_base + CPUDBG_DSCR, dscr);
-error_free_buff_r:
- LOG_ERROR("error");
- free(tmp_buff);
- return ERROR_FAIL;
+ /* Done. */
+ return final_retval;
}
projects / openocd / commitdiff