target: added events TARGET_EVENT_STEP_START and _END

Events TARGET_EVENT_STEP_START and TARGET_EVENT_STEP_END
have been added - analogous to already existing events
TARGET_EVENT_RESUME_*.

This is an example of a concrete use case where having
these events is important:

In RISC-V processors without Debug Program Buffer, OpenOCD
cannot execute fence/fence.i when resuming or single-
stepping. With these events implemented, the user can
instead provide custom operations to achieve that same
effect prior to resuming the processor.

Change-Id: I786348ff08940759d99b0f24e9e0ed5a44581094
Signed-off-by: Jan Matyas <matyas@codasip.com>
Reviewed-on: http://openocd.zylin.com/5551
Tested-by: jenkins
Reviewed-by: Tim Newsome <tim@sifive.com>

diff --git a/doc/openocd.texi b/doc/openocd.texi
index 250db326f2a64b4f39ee03213a6f312a0f88f9f8..0c58a682c6649e6abc7542b069c0a77ca9c2cdcb 100644 (file)
--- a/doc/openocd.texi
+++ b/doc/openocd.texi
@@ -4924,6 +4924,10 @@ when reset disables PLLs needed to use a fast clock.
 @* After all targets have resumed
 @item @b{resumed}
 @* Target has resumed
+@item @b{step-start}
+@* Before a target is single-stepped
+@item @b{step-end}
+@* After single-step has completed
 @item @b{trace-config}
 @* After target hardware trace configuration was changed
 @end itemize

diff --git a/src/target/target.c b/src/target/target.c
index 50dd1488f0183f3bf4fc4d5aa180d2e6f43308a3..24fa416f85fef2c6874d72de18281933f5679f76 100644 (file)
--- a/src/target/target.c
+++ b/src/target/target.c
@@ -205,6 +205,8 @@ static const Jim_Nvp nvp_target_event[] = {
        { .value = TARGET_EVENT_RESUMED, .name = "resumed" },
        { .value = TARGET_EVENT_RESUME_START, .name = "resume-start" },
        { .value = TARGET_EVENT_RESUME_END, .name = "resume-end" },
+       { .value = TARGET_EVENT_STEP_START, .name = "step-start" },
+       { .value = TARGET_EVENT_STEP_END, .name = "step-end" },
 
        { .name = "gdb-start", .value = TARGET_EVENT_GDB_START },
        { .name = "gdb-end", .value = TARGET_EVENT_GDB_END },
@@ -1256,7 +1258,17 @@ bool target_supports_gdb_connection(struct target *target)
 int target_step(struct target *target,
                int current, target_addr_t address, int handle_breakpoints)
 {
-       return target->type->step(target, current, address, handle_breakpoints);
+       int retval;
+
+       target_call_event_callbacks(target, TARGET_EVENT_STEP_START);
+
+       retval = target->type->step(target, current, address, handle_breakpoints);
+       if (retval != ERROR_OK)
+               return retval;
+
+       target_call_event_callbacks(target, TARGET_EVENT_STEP_END);
+
+       return retval;
 }
 
 int target_get_gdb_fileio_info(struct target *target, struct gdb_fileio_info *fileio_info)
@@ -3145,7 +3157,7 @@ COMMAND_HANDLER(handle_step_command)
 
        struct target *target = get_current_target(CMD_CTX);
 
-       return target->type->step(target, current_pc, addr, 1);
+       return target_step(target, current_pc, addr, 1);
 }
 
 void target_handle_md_output(struct command_invocation *cmd,

diff --git a/src/target/target.h b/src/target/target.h
index b954ec22d2877f4228c37ec2343dff3b2bb4fce1..ddeb00b57eec25fb6c5fe5871edde038daad1b7a 100644 (file)
--- a/src/target/target.h
+++ b/src/target/target.h
@@ -258,6 +258,8 @@ enum target_event {
        TARGET_EVENT_RESUMED,           /* target resumed to normal execution */
        TARGET_EVENT_RESUME_START,
        TARGET_EVENT_RESUME_END,
+       TARGET_EVENT_STEP_START,
+       TARGET_EVENT_STEP_END,
 
        TARGET_EVENT_GDB_START, /* debugger started execution (step/run) */
        TARGET_EVENT_GDB_END, /* debugger stopped execution (step/run) */