This is an automated email from Gerrit.
Manuel Wick (man...@matronix.de) just uploaded a new patch set to Gerrit, which
you can find at http://openocd.zylin.com/6044
-- gerrit
commit 9ce02df52e47b812baad19cdc91dbef4d90deb8d
Author: Manuel Wick <man...@matronix.de>
Date: Sat Jan 30 22:46:50 2021 +0100
remote_bitbang: Add SWD support
This adds the new command characters to make SWD work with the new split
jtag and swd operations of bitbang.
The command characters are as follows:
O - SWDIO drive 1 (swd_drive)
o - SWDIO drive 0
c - SWDIO read request
d - SWD write 0 0
e - SWD write 0 1
f - SWD write 1 0
g - SWD write 1 1
Documentation has been updated accordingly. The new commands will be
used by an adapted version of the jtag-openocd applet of the "Glasgow
Debug Tool" (https://github.com/glasgowEmbedded/Glasgow).
It has been tested against an stm32f103 and an at91samd21 target.
Change-Id: I8e998a2cb36905142cb16e534483094cd99e8fa7
Signed-off-by: Manuel Wick <man...@matronix.de>
diff --git a/doc/manual/jtag/drivers/remote_bitbang.txt
b/doc/manual/jtag/drivers/remote_bitbang.txt
index f394d73..5f4fd1b 100644
--- a/doc/manual/jtag/drivers/remote_bitbang.txt
+++ b/doc/manual/jtag/drivers/remote_bitbang.txt
@@ -1,15 +1,19 @@
/** @remote_bitbangpage OpenOCD Developer's Guide
-The remote_bitbang JTAG driver is used to drive JTAG from a remote process. The
-remote_bitbang driver communicates via TCP or UNIX sockets with some remote
-process using an ASCII encoding of the bitbang interface. The remote process
-presumably then drives the JTAG however it pleases. The remote process should
-act as a server, listening for connections from the openocd remote_bitbang
-driver.
+The remote_bitbang JTAG+SWD driver is used to drive JTAG and/or SWD from a
+remote process. The remote_bitbang driver communicates via TCP or UNIX
+sockets with some remote process using an ASCII encoding of the bitbang
+interface. The remote process presumably then drives the JTAG/SWD however
+it pleases. The remote process should act as a server, listening for
+connections from the openocd remote_bitbang driver.
The remote bitbang driver is useful for debugging software running on
processors which are being simulated.
+There also is an implementation of the server-side protocol for the
+Glasgow Debug Tool (https://github.com/glasgowEmbedded/Glasgow) through
+the jtag-openocd applet.
+
The bitbang interface consists of the following functions.
blink on
@@ -24,11 +28,20 @@ write tck tms tdi
reset trst srst
Set the value of trst, srst.
+swdio_drive
+ Set the output enable of the bidirectional swdio (tms) pin
+
+swdio_read
+ Sample the value of swdio (tms).
+
+swd_write
+ Set the value of swclk (tck) and swdio (tms).
+
An additional function, quit, is added to the remote_bitbang interface to
indicate there will be no more requests and the connection with the remote
driver should be closed.
-These five functions are encoded in ASCII by assigning a single character to
+These eight functions are encoded in ASCII by assigning a single character to
each possible request. The assignments are:
B - Blink on
@@ -47,7 +60,14 @@ each possible request. The assignments are:
s - Reset 0 1
t - Reset 1 0
u - Reset 1 1
+ O - SWDIO drive 1 (swd_drive)
+ o - SWDIO drive 0
+ c - SWDIO read request
+ d - SWD write 0 0
+ e - SWD write 0 1
+ f - SWD write 1 0
+ g - SWD write 1 1
-The read response is encoded in ASCII as either digit 0 or 1.
+The read responses are encoded in ASCII as either digit 0 or 1.
*/
diff --git a/src/jtag/drivers/remote_bitbang.c
b/src/jtag/drivers/remote_bitbang.c
index 6637952..62366d3 100644
--- a/src/jtag/drivers/remote_bitbang.c
+++ b/src/jtag/drivers/remote_bitbang.c
@@ -2,6 +2,8 @@
* Copyright (C) 2011 by Richard Uhler *
* ruh...@mit.edu *
* *
+ * Copyright (C) 2021 by Manuel Wick <man...@matronix.de> *
+ * *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
@@ -194,11 +196,35 @@ static int remote_bitbang_blink(int on)
return remote_bitbang_putc(c);
}
+static void remote_bitbang_swdio_drive(bool is_output)
+{
+ char c = is_output ? 'O' : 'o';
+ if (0 != remote_bitbang_putc(c))
+ LOG_ERROR("Error setting direction for swdio");
+}
+
+static int remote_bitbang_swdio_read(void)
+{
+ if (BB_ERROR != remote_bitbang_putc('c'))
+ return remote_bitbang_rread();
+ else
+ return BB_ERROR;
+}
+
+static int remote_bitbang_swd_write(int swclk, int swdio)
+{
+ char c = 'd' + ((swclk ? 0x2 : 0x0) | (swdio ? 0x1 : 0x0));
+ return remote_bitbang_putc(c);
+}
+
static struct bitbang_interface remote_bitbang_bitbang = {
.buf_size = sizeof(remote_bitbang_buf) - 1,
.sample = &remote_bitbang_sample,
.read_sample = &remote_bitbang_read_sample,
.write = &remote_bitbang_write,
+ .swdio_read = &remote_bitbang_swdio_read,
+ .swdio_drive = &remote_bitbang_swdio_drive,
+ .swd_write = &remote_bitbang_swd_write,
.blink = &remote_bitbang_blink,
};
@@ -321,6 +347,8 @@
COMMAND_HANDLER(remote_bitbang_handle_remote_bitbang_host_command)
return ERROR_COMMAND_SYNTAX_ERROR;
}
+static const char * const remote_bitbang_transports[] = { "jtag", "swd", NULL
};
+
static const struct command_registration remote_bitbang_command_handlers[] = {
{
.name = "remote_bitbang_port",
@@ -347,7 +375,7 @@ static struct jtag_interface remote_bitbang_interface = {
struct adapter_driver remote_bitbang_adapter_driver = {
.name = "remote_bitbang",
- .transports = jtag_only,
+ .transports = remote_bitbang_transports,
.commands = remote_bitbang_command_handlers,
.init = &remote_bitbang_init,
@@ -355,4 +383,5 @@ struct adapter_driver remote_bitbang_adapter_driver = {
.reset = &remote_bitbang_reset,
.jtag_ops = &remote_bitbang_interface,
+ .swd_ops = &bitbang_swd,
};
--
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