Add command to erase all flash memory regions

Changes in v4:

- Replaced phex call with hex_string.

Changes in v3:

- Addressed comments by Pedro.
- Output of memory region size now in hex format.
- Misc formatting fixups.
- Addressed Simon's comments on formatting.
- Adjusted command text in the manual entry.
- Fixed up ChangeLog.
- Renamed flash_erase_all_command to flash_erase_command.

Changes in v2:

- Added NEWS entry.
- Fixed long lines.
- Address printing with paddress.

Years ago we contributed flash programming patches upstream.  The following
patch is a leftover one that complements that functionality by adding a new
command to erase all reported flash memory blocks.

The command is most useful when we're dealing with flash-enabled targets
(mostly bare-metal) and we need to reset the board for some reason.

The wiping out of flash memory regions should help the target come up with a
known clean state from which the user can load a new image and resume
debugging. It is convenient enough to do this from the debugger, and there is
also an MI command to expose this functionality to the IDE's.

gdb/doc/ChangeLog:

2017-01-20  Mike Wrighton  <mike_wrighton@codesourcery.com>
	    Luis Machado  <lgustavo@codesourcery.com>

	* gdb.texinfo (-target-flash-erase): New MI command description.
	(flash-erase): New CLI command description.

gdb/ChangeLog:

2017-01-20  Mike Wrighton  <mike_wrighton@codesourcery.com>
	    Luis Machado  <lgustavo@codesourcery.com>

	* NEWS (New commands): Mention flash-erase.
	(New MI commands): Mention target-flash-erase.
	* mi/mi-cmds.c (mi_cmd_target_flash_erase): Add target-flash-erase MI
	command.
	* mi/mi-cmds.h (mi_cmd_target_flash_erase): New declaration.
	* mi/mi-main.c (mi_cmd_target_flash_erase): New function.
	* target.c (flash_erase_command): New function.
	(initialize_targets): Add new flash-erase command.
	* target.h (flash_erase_command): New declaration.

3 files changed, 8 insertions, 0 deletions

diff --git a/gdb/mi/mi-cmds.c b/gdb/mi/mi-cmds.c
index cdea008..abb70bd 100644
--- a/gdb/mi/mi-cmds.c
+++ b/gdb/mi/mi-cmds.c
@@ -147,6 +147,7 @@ static struct mi_cmd mi_cmds[] =
   DEF_MI_CMD_MI ("target-file-delete", mi_cmd_target_file_delete),
   DEF_MI_CMD_MI ("target-file-get", mi_cmd_target_file_get),
   DEF_MI_CMD_MI ("target-file-put", mi_cmd_target_file_put),
+  DEF_MI_CMD_MI ("target-flash-erase", mi_cmd_target_flash_erase),
   DEF_MI_CMD_CLI ("target-select", "target", 1),
   DEF_MI_CMD_MI ("thread-info", mi_cmd_thread_info),
   DEF_MI_CMD_MI ("thread-list-ids", mi_cmd_thread_list_ids),
diff --git a/gdb/mi/mi-cmds.h b/gdb/mi/mi-cmds.h
index 8bd947b..d0906e6 100644
--- a/gdb/mi/mi-cmds.h
+++ b/gdb/mi/mi-cmds.h
@@ -93,6 +93,7 @@ extern mi_cmd_argv_ftype mi_cmd_target_detach;
 extern mi_cmd_argv_ftype mi_cmd_target_file_get;
 extern mi_cmd_argv_ftype mi_cmd_target_file_put;
 extern mi_cmd_argv_ftype mi_cmd_target_file_delete;
+extern mi_cmd_argv_ftype mi_cmd_target_flash_erase;
 extern mi_cmd_argv_ftype mi_cmd_thread_info;
 extern mi_cmd_argv_ftype mi_cmd_thread_list_ids;
 extern mi_cmd_argv_ftype mi_cmd_thread_select;
diff --git a/gdb/mi/mi-main.c b/gdb/mi/mi-main.c
index 22803cb..57c23eb 100644
--- a/gdb/mi/mi-main.c
+++ b/gdb/mi/mi-main.c
@@ -553,6 +553,12 @@ mi_cmd_target_detach (char *command, char **argv, int argc)
 }
 
 void
+mi_cmd_target_flash_erase (char *command, char **argv, int argc)
+{
+  flash_erase_command (NULL, 0);
+}
+
+void
 mi_cmd_thread_select (char *command, char **argv, int argc)
 {
   enum gdb_rc rc;