From 1d140c4dcd79cf5e6257d53986db23dc71c2521b Mon Sep 17 00:00:00 2001 From: David Brownell Date: Thu, 14 Jan 2010 12:45:58 -0800 Subject: [PATCH] ARM7/ARM9: improved reset support Teach most remaining ARM cores how to use the "reset-assert" event. Same model as elsewhere: iff a handler is provided for that event, use that instead of trying to assert SRST (which may be unavailable, or inappropriate since it resets too much). Else no change. Signed-off-by: David Brownell --- src/target/arm7_9_common.c | 37 +++++++++++++++++++++++-------------- 1 file changed, 23 insertions(+), 14 deletions(-) diff --git a/src/target/arm7_9_common.c b/src/target/arm7_9_common.c index baf3e45b3..ca1d84f5d 100644 --- a/src/target/arm7_9_common.c +++ b/src/target/arm7_9_common.c @@ -944,13 +944,15 @@ int arm7_9_assert_reset(struct target *target) { struct arm7_9_common *arm7_9 = target_to_arm7_9(target); enum reset_types jtag_reset_config = jtag_get_reset_config(); + bool use_event = false; LOG_DEBUG("target->state: %s", target_state_name(target)); - if (!(jtag_reset_config & RESET_HAS_SRST)) - { - LOG_ERROR("Can't assert SRST"); + if (target_has_event_action(target, TARGET_EVENT_RESET_ASSERT)) + use_event = true; + else if (!(jtag_reset_config & RESET_HAS_SRST)) { + LOG_ERROR("%s: how to reset?", target_name(target)); return ERROR_FAIL; } @@ -965,7 +967,8 @@ int arm7_9_assert_reset(struct target *target) */ bool srst_asserted = false; - if (((jtag_reset_config & RESET_SRST_PULLS_TRST) == 0) + if (!use_event + && !(jtag_reset_config & RESET_SRST_PULLS_TRST) && (jtag_reset_config & RESET_SRST_NO_GATING)) { jtag_add_reset(0, 1); @@ -1015,22 +1018,28 @@ int arm7_9_assert_reset(struct target *target) } } - /* here we should issue an SRST only, but we may have to assert TRST as well */ - if (jtag_reset_config & RESET_SRST_PULLS_TRST) - { - jtag_add_reset(1, 1); - } else if (!srst_asserted) - { - jtag_add_reset(0, 1); + if (use_event) { + target_handle_event(target, TARGET_EVENT_RESET_ASSERT); + } else { + /* If we use SRST ... we'd like to issue just SRST, but the + * board or chip may be set up so we have to assert TRST as + * well. On some chips that combination is equivalent to a + * power-up reset, and generally clobbers EICE state. + */ + if (jtag_reset_config & RESET_SRST_PULLS_TRST) + jtag_add_reset(1, 1); + else if (!srst_asserted) + jtag_add_reset(0, 1); + jtag_add_sleep(50000); } target->state = TARGET_RESET; - jtag_add_sleep(50000); - register_cache_invalidate(arm7_9->armv4_5_common.core_cache); + /* REVISIT why isn't standard debug entry logic sufficient?? */ if (target->reset_halt - && !(jtag_reset_config & RESET_SRST_PULLS_TRST)) + && (!(jtag_reset_config & RESET_SRST_PULLS_TRST) + || use_event)) { /* debug entry was prepared above */ target->debug_reason = DBG_REASON_DBGRQ; -- 2.11.4.GIT