From 67332532194b16b99f0535a41b4179ca5df349b0 Mon Sep 17 00:00:00 2001
From: Paul Fertser <fercerpav@gmail.com>
Date: Wed, 14 May 2014 11:42:16 +0400
Subject: [PATCH] drivers/jtag/jlink: support SWD mode
Quick attempt at SWD support, closely modelled after ftdi.
Change-Id: I25140d80c5be7b2f8f0e2ef722a4ba4df0da4cf3
Signed-off-by: Brian Campbell <Brian.Campbell@ed.ac.uk>
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: http://openocd.zylin.com/2141
Tested-by: jenkins
Reviewed-by: Nemui Trinomius <nemuisan_kawausogasuki@live.jp>
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>
---
src/jtag/drivers/jlink.c | 265 +++++++++++++++++++++++++++++++++++++--
1 file changed, 255 insertions(+), 10 deletions(-)
diff --git a/src/jtag/drivers/jlink.c b/src/jtag/drivers/jlink.c
index 632dcee4f..871bf24c6 100644
--- a/src/jtag/drivers/jlink.c
+++ b/src/jtag/drivers/jlink.c
@@ -29,6 +29,7 @@
#endif
#include <jtag/interface.h>
+#include <jtag/swd.h>
#include <jtag/commands.h>
#include "libusb_common.h"
@@ -201,6 +202,11 @@ static char *jlink_hw_type_str[] = {
"J-Link Pro",
};
+#define JLINK_TIF_JTAG 0
+#define JLINK_TIF_SWD 1
+#define JLINK_SWD_DIR_IN 0
+#define JLINK_SWD_DIR_OUT 1
+
/* Queue command functions */
static void jlink_end_state(tap_state_t state);
static void jlink_state_move(void);
@@ -211,6 +217,9 @@ static void jlink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer,
static void jlink_reset(int trst, int srst);
static void jlink_simple_command(uint8_t command);
static int jlink_get_status(void);
+static int jlink_swd_run_queue(struct adiv5_dap *dap);
+static void jlink_swd_queue_cmd(struct adiv5_dap *dap, uint8_t cmd, uint32_t *dst, uint32_t data);
+static int jlink_swd_switch_seq(struct adiv5_dap *dap, enum swd_special_seq seq);
/* J-Link tap buffer functions */
static void jlink_tap_init(void);
@@ -254,6 +263,9 @@ static uint16_t pids[] = { 0x0101, 0x0102, 0x0103, 0x0104, 0x0105, 0 };
static uint32_t jlink_caps;
static uint32_t jlink_hw_type;
+static int queued_retval;
+static bool swd_mode;
+
/* 256 byte non-volatile memory */
struct jlink_config {
uint8_t usb_address;
@@ -529,11 +541,17 @@ static int jlink_init(void)
*
* Segger recommends to select interface necessarily as a part of init process,
* in case any previous session leaves improper interface selected.
- *
- * Until SWD implemented, select only JTAG interface here.
*/
+ int retval;
if (jlink_caps & (1<<EMU_CAP_SELECT_IF))
- jlink_select_interface(0);
+ retval = jlink_select_interface(swd_mode ? JLINK_TIF_SWD : JLINK_TIF_JTAG);
+ else
+ retval = swd_mode ? ERROR_JTAG_DEVICE_ERROR : ERROR_OK;
+
+ if (retval != ERROR_OK) {
+ LOG_ERROR("Selected transport mode is not supported.");
+ return ERROR_JTAG_INIT_FAILED;
+ }
LOG_INFO("J-Link JTAG Interface ready");
@@ -541,11 +559,19 @@ static int jlink_init(void)
jtag_sleep(3000);
jlink_tap_init();
- /* v5/6 jlink seems to have an issue if the first tap move
- * is not divisible by 8, so we send a TLR on first power up */
- for (i = 0; i < 8; i++)
- jlink_tap_append_step(1, 0);
- jlink_tap_execute();
+ if (!swd_mode) {
+ /* v5/6 jlink seems to have an issue if the first tap move
+ * is not divisible by 8, so we send a TLR on first power up */
+ for (i = 0; i < 8; i++)
+ jlink_tap_append_step(1, 0);
+ jlink_tap_execute();
+ }
+
+ if (swd_mode)
+ jlink_swd_switch_seq(NULL, JTAG_TO_SWD);
+ else
+ jlink_swd_switch_seq(NULL, SWD_TO_JTAG);
+ jlink_swd_run_queue(NULL);
return ERROR_OK;
}
@@ -1294,10 +1320,50 @@ static const struct command_registration jlink_command_handlers[] = {
COMMAND_REGISTRATION_DONE
};
+static int jlink_swd_init(void)
+{
+ LOG_INFO("JLink SWD mode enabled");
+ swd_mode = true;
+
+ return ERROR_OK;
+}
+
+static void jlink_swd_write_reg(struct adiv5_dap *dap, uint8_t cmd, uint32_t value)
+{
+ assert(!(cmd & SWD_CMD_RnW));
+ jlink_swd_queue_cmd(dap, cmd, NULL, value);
+}
+
+static void jlink_swd_read_reg(struct adiv5_dap *dap, uint8_t cmd, uint32_t *value)
+{
+ assert(cmd & SWD_CMD_RnW);
+ jlink_swd_queue_cmd(dap, cmd, value, 0);
+}
+
+static int_least32_t jlink_swd_frequency(struct adiv5_dap *dap, int_least32_t hz)
+{
+ if (hz > 0)
+ jlink_speed(hz);
+
+ return hz;
+}
+
+static const struct swd_driver jlink_swd = {
+ .init = jlink_swd_init,
+ .frequency = jlink_swd_frequency,
+ .switch_seq = jlink_swd_switch_seq,
+ .read_reg = jlink_swd_read_reg,
+ .write_reg = jlink_swd_write_reg,
+ .run = jlink_swd_run_queue,
+};
+
+static const char * const jlink_transports[] = { "jtag", "swd", NULL };
+
struct jtag_interface jlink_interface = {
.name = "jlink",
.commands = jlink_command_handlers,
- .transports = jtag_only,
+ .transports = jlink_transports,
+ .swd = &jlink_swd,
.execute_queue = jlink_execute_queue,
.speed = jlink_speed,
@@ -1312,6 +1378,7 @@ struct jtag_interface jlink_interface = {
static unsigned tap_length;
+/* In SWD mode use tms buffer for direction control */
static uint8_t tms_buffer[JLINK_TAP_BUFFER_SIZE];
static uint8_t tdi_buffer[JLINK_TAP_BUFFER_SIZE];
static uint8_t tdo_buffer[JLINK_TAP_BUFFER_SIZE];
@@ -1320,7 +1387,7 @@ struct pending_scan_result {
int first; /* First bit position in tdo_buffer to read */
int length; /* Number of bits to read */
struct scan_command *command; /* Corresponding scan command */
- uint8_t *buffer;
+ void *buffer;
};
#define MAX_PENDING_SCAN_RESULTS 256
@@ -1465,6 +1532,184 @@ static int jlink_tap_execute(void)
return ERROR_OK;
}
+static void fill_buffer(uint8_t *buf, uint32_t val, uint32_t len)
+{
+ unsigned int tap_pos = tap_length;
+
+ while (len > 32) {
+ buf_set_u32(buf, tap_pos, 32, val);
+ len -= 32;
+ tap_pos += 32;
+ }
+ if (len)
+ buf_set_u32(buf, tap_pos, len, val);
+}
+
+static void jlink_queue_data_out(const uint8_t *data, uint32_t len)
+{
+ const uint32_t dir_out = 0xffffffff;
+
+ if (data)
+ bit_copy(tdi_buffer, tap_length, data, 0, len);
+ else
+ fill_buffer(tdi_buffer, 0, len);
+ fill_buffer(tms_buffer, dir_out, len);
+ tap_length += len;
+}
+
+static void jlink_queue_data_in(uint32_t len)
+{
+ const uint32_t dir_in = 0;
+
+ fill_buffer(tms_buffer, dir_in, len);
+ tap_length += len;
+}
+
+static int jlink_swd_switch_seq(struct adiv5_dap *dap, enum swd_special_seq seq)
+{
+ const uint8_t *s;
+ unsigned int s_len;
+
+ switch (seq) {
+ case LINE_RESET:
+ LOG_DEBUG("SWD line reset");
+ s = swd_seq_line_reset;
+ s_len = swd_seq_line_reset_len;
+ break;
+ case JTAG_TO_SWD:
+ LOG_DEBUG("JTAG-to-SWD");
+ s = swd_seq_jtag_to_swd;
+ s_len = swd_seq_jtag_to_swd_len;
+ break;
+ case SWD_TO_JTAG:
+ LOG_DEBUG("SWD-to-JTAG");
+ s = swd_seq_swd_to_jtag;
+ s_len = swd_seq_swd_to_jtag_len;
+ break;
+ default:
+ LOG_ERROR("Sequence %d not supported", seq);
+ return ERROR_FAIL;
+ }
+
+ jlink_queue_data_out(s, s_len);
+
+ return ERROR_OK;
+}
+
+static int jlink_swd_run_queue(struct adiv5_dap *dap)
+{
+ LOG_DEBUG("Executing %d queued transactions", pending_scan_results_length);
+ int retval;
+
+ if (queued_retval != ERROR_OK) {
+ LOG_DEBUG("Skipping due to previous errors: %d", queued_retval);
+ goto skip;
+ }
+
+ /* A transaction must be followed by another transaction or at least 8 idle cycles to
+ * ensure that data is clocked through the AP. */
+ jlink_queue_data_out(NULL, 8);
+
+ size_t byte_length = DIV_ROUND_UP(tap_length, 8);
+
+ /* There's a comment in jlink_tap_execute saying JLink returns
+ * an extra NULL in packet when size of incoming message is a
+ * multiple of 64. Someone should verify if that's still the
+ * case with the current jlink firmware */
+
+ usb_out_buffer[0] = EMU_CMD_HW_JTAG3;
+ usb_out_buffer[1] = 0;
+ usb_out_buffer[2] = (tap_length >> 0) & 0xff;
+ usb_out_buffer[3] = (tap_length >> 8) & 0xff;
+ memcpy(usb_out_buffer + 4, tms_buffer, byte_length);
+ memcpy(usb_out_buffer + 4 + byte_length, tdi_buffer, byte_length);
+
+ retval = jlink_usb_message(jlink_handle, 4 + 2 * byte_length,
+ byte_length + 1);
+ if (retval != ERROR_OK) {
+ LOG_ERROR("jlink_swd_run_queue failed USB io (%d)", retval);
+ goto skip;
+ }
+
+ retval = usb_in_buffer[byte_length];
+ if (retval) {
+ LOG_ERROR("jlink_swd_run_queue failed, result %d", retval);
+ goto skip;
+ }
+
+ for (int i = 0; i < pending_scan_results_length; i++) {
+ int ack = buf_get_u32(usb_in_buffer, pending_scan_results_buffer[i].first, 3);
+
+ if (ack != SWD_ACK_OK) {
+ LOG_ERROR("SWD ack not OK: %d %s", ack,
+ ack == SWD_ACK_WAIT ? "WAIT" : ack == SWD_ACK_FAULT ? "FAULT" : "JUNK");
+ queued_retval = ack;
+ goto skip;
+ } else if (pending_scan_results_buffer[i].length) {
+ uint32_t data = buf_get_u32(usb_in_buffer, 3 + pending_scan_results_buffer[i].first, 32);
+ int parity = buf_get_u32(usb_in_buffer, 3 + 32 + pending_scan_results_buffer[i].first, 1);
+
+ if (parity != parity_u32(data)) {
+ LOG_ERROR("SWD Read data parity mismatch");
+ queued_retval = ERROR_FAIL;
+ goto skip;
+ }
+
+ if (pending_scan_results_buffer[i].buffer)
+ *(uint32_t *)pending_scan_results_buffer[i].buffer = data;
+ }
+ }
+
+skip:
+ jlink_tap_init();
+ retval = queued_retval;
+ queued_retval = ERROR_OK;
+
+ return retval;
+}
+
+static void jlink_swd_queue_cmd(struct adiv5_dap *dap, uint8_t cmd, uint32_t *dst, uint32_t data)
+{
+ uint8_t data_parity_trn[DIV_ROUND_UP(32 + 1, 8)];
+ if (tap_length + 46 + 8 + dap->memaccess_tck >= sizeof(tdi_buffer) * 8 ||
+ pending_scan_results_length == MAX_PENDING_SCAN_RESULTS) {
+ /* Not enough room in the queue. Run the queue. */
+ queued_retval = jlink_swd_run_queue(dap);
+ }
+
+ if (queued_retval != ERROR_OK)
+ return;
+
+ cmd |= SWD_CMD_START | SWD_CMD_PARK;
+
+ jlink_queue_data_out(&cmd, 8);
+
+ pending_scan_results_buffer[pending_scan_results_length].first = tap_length;
+
+ if (cmd & SWD_CMD_RnW) {
+ /* Queue a read transaction */
+ pending_scan_results_buffer[pending_scan_results_length].length = 32;
+ pending_scan_results_buffer[pending_scan_results_length].buffer = dst;
+
+ jlink_queue_data_in(1 + 3 + 32 + 1 + 1);
+ } else {
+ /* Queue a write transaction */
+ pending_scan_results_buffer[pending_scan_results_length].length = 0;
+ jlink_queue_data_in(1 + 3 + 1);
+
+ buf_set_u32(data_parity_trn, 0, 32, data);
+ buf_set_u32(data_parity_trn, 32, 1, parity_u32(data));
+
+ jlink_queue_data_out(data_parity_trn, 32 + 1);
+ }
+
+ pending_scan_results_length++;
+
+ /* Insert idle cycles after AP accesses to avoid WAIT */
+ if (cmd & SWD_CMD_APnDP)
+ jlink_queue_data_out(NULL, dap->memaccess_tck);
+}
+
/*****************************************************************************/
/* JLink USB low-level functions */