diff options
Diffstat (limited to 'src/jtag/jtag.h')
| -rw-r--r-- | src/jtag/jtag.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/src/jtag/jtag.h b/src/jtag/jtag.h index 19329447..b7ce094d 100644 --- a/src/jtag/jtag.h +++ b/src/jtag/jtag.h @@ -241,8 +241,12 @@ enum reset_types extern enum reset_types jtag_reset_config; -/* JTAG subsystem */ +/* initialize JTAG chain using only a TLR reset. If init fails, + * try reset + init. + */ extern int jtag_init(struct command_context_s *cmd_ctx); +/* reset, then initialize JTAG chain */ +extern int jtag_init_reset(struct command_context_s *cmd_ctx); extern int jtag_register_commands(struct command_context_s *cmd_ctx); /* JTAG interface, can be implemented with a software or hardware fifo @@ -325,6 +329,10 @@ extern int interface_jtag_add_runtest(int num_cycles, enum tap_state endstate); * This is why combinations such as "reset_config srst_only srst_pulls_trst" * are supported. * + * only req_tlr_or_trst and srst can have a transition for a + * call as the effects of transitioning both at the "same time" + * are undefined, but when srst_pulls_trst or vice versa, + * then trst & srst *must* be asserted together. */ extern void jtag_add_reset(int req_tlr_or_trst, int srst); /* this drives the actual srst and trst pins. srst will always be 0 |