diff options
| -rw-r--r-- | src/helper/binarybuffer.h | 2 | ||||
| -rw-r--r-- | src/jtag/core.c | 53 |
2 files changed, 42 insertions, 13 deletions
diff --git a/src/helper/binarybuffer.h b/src/helper/binarybuffer.h index 6d66c189..eef4057a 100644 --- a/src/helper/binarybuffer.h +++ b/src/helper/binarybuffer.h @@ -86,7 +86,7 @@ extern char* buf_to_str(const uint8_t *buf, int size, int radix); struct scan_field_s; extern int buf_to_u32_handler(uint8_t *in_buf, void *priv, struct scan_field_s *field); -#define CEIL(m, n) ((m + n - 1) / n) +#define CEIL(m, n) (((m) + (n) - 1) / (n)) /* read a uint32_t from a buffer in target memory endianness */ static inline uint32_t fast_target_buffer_get_u32(const uint8_t *buffer, int little) diff --git a/src/jtag/core.c b/src/jtag/core.c index f9ebb3fa..b1d3ca0f 100644 --- a/src/jtag/core.c +++ b/src/jtag/core.c @@ -847,6 +847,9 @@ void jtag_sleep(uint32_t us) #define EXTRACT_PART(X) (((X) & 0xffff000) >> 12) #define EXTRACT_VER(X) (((X) & 0xf0000000) >> 28) +/* A reserved manufacturer ID is used in END_OF_CHAIN_FLAG, so we + * know that no valid TAP will have it as an IDCODE value. + */ #define END_OF_CHAIN_FLAG 0x000000ff static int jtag_examine_chain_execute(uint8_t *idcode_buffer, unsigned num_idcode) @@ -964,6 +967,7 @@ static bool jtag_examine_chain_match_tap(const struct jtag_tap_s *tap) } /* Try to examine chain layout according to IEEE 1149.1 §12 + * This is called a "blind interrogation" of the scan chain. */ static int jtag_examine_chain(void) { @@ -1037,7 +1041,12 @@ static int jtag_examine_chain(void) return ERROR_OK; } -int jtag_validate_chain(void) +/* + * Validate the date loaded by entry to the Capture-IR state, to help + * find errors related to scan chain configuration (wrong IR lengths) + * or communication. + */ +static int jtag_validate_ircapture(void) { jtag_tap_t *tap; int total_ir_length = 0; @@ -1056,7 +1065,11 @@ int jtag_validate_chain(void) } total_ir_length += 2; + ir_test = malloc(CEIL(total_ir_length, 8)); + if (ir_test == NULL) + return ERROR_FAIL; + buf_set_ones(ir_test, total_ir_length); field.tap = NULL; @@ -1082,24 +1095,37 @@ int jtag_validate_chain(void) break; } + /* Validate the two LSBs, which must be 01 per JTAG spec. + * REVISIT we might be able to verify some MSBs too, using + * ircapture/irmask attributes. + */ val = buf_get_u32(ir_test, chain_pos, 2); - /* Only fail this check if we have IDCODE for this device */ - if ((val != 0x1)&&(tap->hasidcode)) - { + if (val != 1) { char *cbuf = buf_to_str(ir_test, total_ir_length, 16); - LOG_ERROR("Could not validate JTAG scan chain, IR mismatch, scan returned 0x%s. tap=%s pos=%d expected 0x1 got %0x", cbuf, jtag_tap_name(tap), chain_pos, val); - free(cbuf); - free(ir_test); - return ERROR_JTAG_INIT_FAILED; + + LOG_ERROR("%s: IR capture error; saw 0x%s not 0x..1", + jtag_tap_name(tap), cbuf); + + /* Fail only if we have IDCODE for this device. + * REVISIT -- why not fail-always? + */ + if (tap->hasidcode) { + free(cbuf); + free(ir_test); + return ERROR_JTAG_INIT_FAILED; + } } chain_pos += tap->ir_length; } + /* verify the '11' sentinel we wrote is returned at the end */ val = buf_get_u32(ir_test, chain_pos, 2); if (val != 0x3) { char *cbuf = buf_to_str(ir_test, total_ir_length, 16); - LOG_ERROR("Could not validate end of JTAG scan chain, IR mismatch, scan returned 0x%s. pos=%d expected 0x3 got %0x", cbuf, chain_pos, val); + + LOG_ERROR("IR capture error at bit %d, saw 0x%s not 0x...3", + chain_pos, cbuf); free(cbuf); free(ir_test); return ERROR_JTAG_INIT_FAILED; @@ -1115,6 +1141,7 @@ void jtag_tap_init(jtag_tap_t *tap) { assert(0 != tap->ir_length); + /// @todo fix, this allocates one byte per bit for all three fields! tap->expected = malloc(tap->ir_length); tap->expected_mask = malloc(tap->ir_length); tap->cur_instr = malloc(tap->ir_length); @@ -1132,7 +1159,8 @@ void jtag_tap_init(jtag_tap_t *tap) LOG_DEBUG("Created Tap: %s @ abs position %d, " "irlen %d, capture: 0x%x mask: 0x%x", tap->dotted_name, tap->abs_chain_position, tap->ir_length, - (unsigned int)(tap->ir_capture_value), (unsigned int)(tap->ir_capture_mask)); + (unsigned) tap->ir_capture_value, + (unsigned) tap->ir_capture_mask); jtag_tap_add(tap); } @@ -1141,6 +1169,7 @@ void jtag_tap_free(jtag_tap_t *tap) jtag_unregister_event_callback(&jtag_reset_callback, tap); /// @todo is anything missing? no memory leaks please + free((void *)tap->expected); free((void *)tap->expected_ids); free((void *)tap->chip); free((void *)tap->tapname); @@ -1212,9 +1241,9 @@ static int jtag_init_inner(struct command_context_s *cmd_ctx) LOG_ERROR("trying to validate configured JTAG chain anyway..."); } - if (jtag_validate_chain() != ERROR_OK) + if (jtag_validate_ircapture() != ERROR_OK) { - LOG_WARNING("Could not validate JTAG chain, continuing anyway..."); + LOG_WARNING("Errors during IR capture, continuing anyway..."); } return ERROR_OK; |