Add MPSSE communications layer for FTDI chips
authorAndreas Fritiofson <andreas.fritiofson@gmail.com>
Sun, 29 Jan 2012 23:16:41 +0000 (00:16 +0100)
committerPeter Stuge <peter@stuge.se>
Tue, 17 Jul 2012 01:34:01 +0000 (01:34 +0000)
This is a higher-level libftdi replacement for use when implementing
protocol drivers for FT2232, FT2232H or FT4232H. It takes care of device
open/close and, unlike libftdi, also MPSSE command abstraction, command
queueing, buffer handling and return data parsing.

The FTDI device is accessed through libusb-1.0 in asynchronous mode.

Change-Id: I051adb574dcc39f8ca9cd7f6dbe6ae4aeea5f4c8
Signed-off-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>
Reviewed-on: http://openocd.zylin.com/451
Tested-by: jenkins
Reviewed-by: Freddie Chopin <freddie.chopin@gmail.com>
Reviewed-by: Peter Stuge <peter@stuge.se>
src/jtag/drivers/mpsse.c [new file with mode: 0644]
src/jtag/drivers/mpsse.h [new file with mode: 0644]

diff --git a/src/jtag/drivers/mpsse.c b/src/jtag/drivers/mpsse.c
new file mode 100644 (file)
index 0000000..dbca535
--- /dev/null
@@ -0,0 +1,838 @@
+/**************************************************************************
+ *   Copyright (C) 2012 by Andreas Fritiofson                              *
+ *   andreas.fritiofson@gmail.com                                          *
+ *                                                                         *
+ *   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     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "mpsse.h"
+#include "helper/log.h"
+#include <libusb-1.0/libusb.h>
+
+/* Compatibility define for older libusb-1.0 */
+#ifndef LIBUSB_CALL
+#define LIBUSB_CALL
+#endif
+
+#ifdef _DEBUG_JTAG_IO_
+#define DEBUG_IO(expr...) LOG_DEBUG(expr)
+#define DEBUG_PRINT_BUF(buf, len) \
+       do { \
+               char buf_string[32 * 3 + 1]; \
+               int buf_string_pos = 0; \
+               for (int i = 0; i < len; i++) { \
+                       buf_string_pos += sprintf(buf_string + buf_string_pos, " %02x", buf[i]); \
+                       if (i % 32 == 32 - 1) { \
+                               LOG_DEBUG("%s", buf_string); \
+                               buf_string_pos = 0; \
+                       } \
+               } \
+               if (buf_string_pos > 0) \
+                       LOG_DEBUG("%s", buf_string);\
+       } while (0)
+#else
+#define DEBUG_IO(expr...) do {} while (0)
+#define DEBUG_PRINT_BUF(buf, len) do {} while (0)
+#endif
+
+#define FTDI_DEVICE_OUT_REQTYPE (LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE)
+#define FTDI_DEVICE_IN_REQTYPE (0x80 | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE)
+
+#define BITMODE_MPSSE 0x02
+
+#define SIO_RESET_REQUEST             0x00
+#define SIO_SET_LATENCY_TIMER_REQUEST 0x09
+#define SIO_GET_LATENCY_TIMER_REQUEST 0x0A
+#define SIO_SET_BITMODE_REQUEST       0x0B
+
+#define SIO_RESET_SIO 0
+#define SIO_RESET_PURGE_RX 1
+#define SIO_RESET_PURGE_TX 2
+
+struct mpsse_ctx {
+       libusb_context *usb_ctx;
+       libusb_device_handle *usb_dev;
+       unsigned int usb_write_timeout;
+       unsigned int usb_read_timeout;
+       uint8_t in_ep;
+       uint8_t out_ep;
+       uint16_t max_packet_size;
+       uint16_t index;
+       uint8_t interface;
+       enum ftdi_chip_type type;
+       uint8_t *write_buffer;
+       unsigned write_size;
+       unsigned write_count;
+       uint8_t *read_buffer;
+       unsigned read_size;
+       unsigned read_count;
+       uint8_t *read_chunk;
+       unsigned read_chunk_size;
+       struct bit_copy_queue read_queue;
+};
+
+/* Returns true if the string descriptor indexed by str_index in device matches string */
+static bool string_descriptor_equal(libusb_device_handle *device, uint8_t str_index,
+       const char *string)
+{
+       int retval;
+       char desc_string[256]; /* Max size of string descriptor */
+       retval = libusb_get_string_descriptor_ascii(device, str_index, (unsigned char *)desc_string,
+                       sizeof(desc_string));
+       if (retval < 0) {
+               LOG_ERROR("libusb_get_string_descriptor_ascii() failed with %d", retval);
+               return false;
+       }
+       return strncmp(string, desc_string, sizeof(desc_string)) == 0;
+}
+
+/* Helper to open a libusb device that matches vid, pid, product string and/or serial string.
+ * Set any field to 0 as a wildcard. If the device is found true is returned, with ctx containing
+ * the already opened handle. ctx->interface must be set to the desired interface (channel) number
+ * prior to calling this function. */
+static bool open_matching_device(struct mpsse_ctx *ctx, const uint16_t *vid, const uint16_t *pid,
+       const char *product, const char *serial)
+{
+       libusb_device **list;
+       struct libusb_device_descriptor desc;
+       struct libusb_config_descriptor *config0;
+       int err;
+       bool found = false;
+       ssize_t cnt = libusb_get_device_list(ctx->usb_ctx, &list);
+       if (cnt < 0)
+               LOG_ERROR("libusb_get_device_list() failed with %zi", cnt);
+
+       for (ssize_t i = 0; i < cnt; i++) {
+               libusb_device *device = list[i];
+
+               err = libusb_get_device_descriptor(device, &desc);
+               if (err != LIBUSB_SUCCESS) {
+                       LOG_ERROR("libusb_get_device_descriptor() failed with %d", err);
+                       continue;
+               }
+
+               if (vid && *vid != desc.idVendor)
+                       continue;
+               if (pid && *pid != desc.idProduct)
+                       continue;
+
+               err = libusb_open(device, &ctx->usb_dev);
+               if (err != LIBUSB_SUCCESS) {
+                       LOG_ERROR("libusb_open() failed with %d", err);
+                       continue;
+               }
+
+               if (product && !string_descriptor_equal(ctx->usb_dev, desc.iProduct, product)) {
+                       libusb_close(ctx->usb_dev);
+                       continue;
+               }
+
+               if (serial && !string_descriptor_equal(ctx->usb_dev, desc.iSerialNumber, serial)) {
+                       libusb_close(ctx->usb_dev);
+                       continue;
+               }
+
+               found = true;
+               break;
+       }
+
+       libusb_free_device_list(list, 1);
+
+       if (!found) {
+               LOG_ERROR("no device found");
+               return false;
+       }
+
+       err = libusb_get_config_descriptor(libusb_get_device(ctx->usb_dev), 0, &config0);
+       if (err != LIBUSB_SUCCESS) {
+               LOG_ERROR("libusb_get_config_descriptor() failed with %d", err);
+               libusb_close(ctx->usb_dev);
+               return false;
+       }
+
+       /* Make sure the first configuration is selected */
+       int cfg;
+       err = libusb_get_configuration(ctx->usb_dev, &cfg);
+       if (err != LIBUSB_SUCCESS) {
+               LOG_ERROR("libusb_get_configuration() failed with %d", err);
+               goto error;
+       }
+
+       if (desc.bNumConfigurations > 0 && cfg != config0->bConfigurationValue) {
+               err = libusb_set_configuration(ctx->usb_dev, config0->bConfigurationValue);
+               if (err != LIBUSB_SUCCESS) {
+                       LOG_ERROR("libusb_set_configuration() failed with %d", err);
+                       goto error;
+               }
+       }
+
+       /* Try to detach ftdi_sio kernel module */
+       err = libusb_detach_kernel_driver(ctx->usb_dev, ctx->interface);
+       if (err != LIBUSB_SUCCESS && err != LIBUSB_ERROR_NOT_FOUND
+                       && err != LIBUSB_ERROR_NOT_SUPPORTED) {
+               LOG_ERROR("libusb_detach_kernel_driver() failed with %d", err);
+               goto error;
+       }
+
+       err = libusb_claim_interface(ctx->usb_dev, ctx->interface);
+       if (err != LIBUSB_SUCCESS) {
+               LOG_ERROR("libusb_claim_interface() failed with %d", err);
+               goto error;
+       }
+
+       /* Reset FTDI device */
+       err = libusb_control_transfer(ctx->usb_dev, FTDI_DEVICE_OUT_REQTYPE,
+                       SIO_RESET_REQUEST, SIO_RESET_SIO,
+                       ctx->index, NULL, 0, ctx->usb_write_timeout);
+       if (err < 0) {
+               LOG_ERROR("failed to reset FTDI device: %d", err);
+               goto error;
+       }
+
+       switch (desc.bcdDevice) {
+       case 0x500:
+               ctx->type = TYPE_FT2232C;
+               break;
+       case 0x700:
+               ctx->type = TYPE_FT2232H;
+               break;
+       case 0x800:
+               ctx->type = TYPE_FT4232H;
+               break;
+       default:
+               LOG_ERROR("unsupported FTDI chip type: 0x%04x", desc.bcdDevice);
+               goto error;
+       }
+
+       /* Determine maximum packet size and endpoint addresses */
+       if (!(desc.bNumConfigurations > 0 && ctx->interface < config0->bNumInterfaces
+                       && config0->interface[ctx->interface].num_altsetting > 0))
+               goto desc_error;
+
+       const struct libusb_interface_descriptor *descriptor;
+       descriptor = &config0->interface[ctx->interface].altsetting[0];
+       if (descriptor->bNumEndpoints != 2)
+               goto desc_error;
+
+       ctx->in_ep = 0;
+       ctx->out_ep = 0;
+       for (int i = 0; i < descriptor->bNumEndpoints; i++) {
+               if (descriptor->endpoint[i].bEndpointAddress & 0x80) {
+                       ctx->in_ep = descriptor->endpoint[i].bEndpointAddress;
+                       ctx->max_packet_size =
+                                       descriptor->endpoint[i].wMaxPacketSize;
+               } else {
+                       ctx->out_ep = descriptor->endpoint[i].bEndpointAddress;
+               }
+       }
+
+       if (ctx->in_ep == 0 || ctx->out_ep == 0)
+               goto desc_error;
+
+       libusb_free_config_descriptor(config0);
+       return true;
+
+desc_error:
+       LOG_ERROR("unrecognized USB device descriptor");
+error:
+       libusb_free_config_descriptor(config0);
+       libusb_close(ctx->usb_dev);
+       return false;
+}
+
+struct mpsse_ctx *mpsse_open(const uint16_t *vid, const uint16_t *pid, const char *description,
+       const char *serial, int channel)
+{
+       struct mpsse_ctx *ctx = calloc(1, sizeof(*ctx));
+       int err;
+
+       if (!ctx)
+               return 0;
+
+       bit_copy_queue_init(&ctx->read_queue);
+       ctx->read_chunk_size = 16384;
+       ctx->read_size = 16384;
+       ctx->write_size = 16384;
+       ctx->read_chunk = malloc(ctx->read_chunk_size);
+       ctx->read_buffer = malloc(ctx->read_size);
+       ctx->write_buffer = malloc(ctx->write_size);
+       if (!ctx->read_chunk || !ctx->read_buffer || !ctx->write_buffer)
+               goto error;
+
+       ctx->interface = channel;
+       ctx->index = channel + 1;
+       ctx->usb_read_timeout = 5000;
+       ctx->usb_write_timeout = 5000;
+
+       err = libusb_init(&ctx->usb_ctx);
+       if (err != LIBUSB_SUCCESS) {
+               LOG_ERROR("libusb_init() failed with %d", err);
+               goto error;
+       }
+
+       if (!open_matching_device(ctx, vid, pid, description, serial)) {
+               /* Four hex digits plus terminating zero each */
+               char vidstr[5];
+               char pidstr[5];
+               LOG_ERROR("unable to open ftdi device with vid %s, pid %s, description '%s' and "
+                               "serial '%s'",
+                               vid ? sprintf(vidstr, "%04x", *vid), vidstr : "*",
+                               pid ? sprintf(pidstr, "%04x", *pid), pidstr : "*",
+                               description ? description : "*",
+                               serial ? serial : "*");
+               ctx->usb_dev = 0;
+               goto error;
+       }
+
+       err = libusb_control_transfer(ctx->usb_dev, FTDI_DEVICE_OUT_REQTYPE,
+                       SIO_SET_LATENCY_TIMER_REQUEST, 255, ctx->index, NULL, 0,
+                       ctx->usb_write_timeout);
+       if (err < 0) {
+               LOG_ERROR("unable to set latency timer: %d", err);
+               goto error;
+       }
+
+       err = libusb_control_transfer(ctx->usb_dev,
+                       FTDI_DEVICE_OUT_REQTYPE,
+                       SIO_SET_BITMODE_REQUEST,
+                       0x0b | (BITMODE_MPSSE << 8),
+                       ctx->index,
+                       NULL,
+                       0,
+                       ctx->usb_write_timeout);
+       if (err < 0) {
+               LOG_ERROR("unable to set MPSSE bitmode: %d", err);
+               goto error;
+       }
+
+       mpsse_purge(ctx);
+
+       return ctx;
+error:
+       mpsse_close(ctx);
+       return 0;
+}
+
+void mpsse_close(struct mpsse_ctx *ctx)
+{
+       if (ctx->usb_dev)
+               libusb_close(ctx->usb_dev);
+       if (ctx->usb_ctx)
+               libusb_exit(ctx->usb_ctx);
+       bit_copy_discard(&ctx->read_queue);
+       if (ctx->write_buffer)
+               free(ctx->write_buffer);
+       if (ctx->read_buffer)
+               free(ctx->read_buffer);
+       if (ctx->read_chunk)
+               free(ctx->read_chunk);
+
+       free(ctx);
+}
+
+bool mpsse_is_high_speed(struct mpsse_ctx *ctx)
+{
+       return ctx->type != TYPE_FT2232C;
+}
+
+void mpsse_purge(struct mpsse_ctx *ctx)
+{
+       int err;
+       LOG_DEBUG("-");
+       ctx->write_count = 0;
+       ctx->read_count = 0;
+       bit_copy_discard(&ctx->read_queue);
+       err = libusb_control_transfer(ctx->usb_dev, FTDI_DEVICE_OUT_REQTYPE, SIO_RESET_REQUEST,
+                       SIO_RESET_PURGE_RX, ctx->index, NULL, 0, ctx->usb_write_timeout);
+       if (err < 0) {
+               LOG_ERROR("unable to purge ftdi rx buffers: %d", err);
+               return;
+       }
+
+       err = libusb_control_transfer(ctx->usb_dev, FTDI_DEVICE_OUT_REQTYPE, SIO_RESET_REQUEST,
+                       SIO_RESET_PURGE_TX, ctx->index, NULL, 0, ctx->usb_write_timeout);
+       if (err < 0) {
+               LOG_ERROR("unable to purge ftdi tx buffers: %d", err);
+               return;
+       }
+}
+
+static unsigned buffer_write_space(struct mpsse_ctx *ctx)
+{
+       /* Reserve one byte for SEND_IMMEDIATE */
+       return ctx->write_size - ctx->write_count - 1;
+}
+
+static unsigned buffer_read_space(struct mpsse_ctx *ctx)
+{
+       return ctx->read_size - ctx->read_count;
+}
+
+static void buffer_write_byte(struct mpsse_ctx *ctx, uint8_t data)
+{
+       DEBUG_IO("%02x", data);
+       assert(ctx->write_count < ctx->write_size);
+       ctx->write_buffer[ctx->write_count++] = data;
+}
+
+static unsigned buffer_write(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset,
+       unsigned bit_count)
+{
+       DEBUG_IO("%d bits", bit_count);
+       assert(ctx->write_count + DIV_ROUND_UP(bit_count, 8) <= ctx->write_size);
+       bit_copy(ctx->write_buffer + ctx->write_count, 0, out, out_offset, bit_count);
+       ctx->write_count += DIV_ROUND_UP(bit_count, 8);
+       return bit_count;
+}
+
+static unsigned buffer_add_read(struct mpsse_ctx *ctx, uint8_t *in, unsigned in_offset,
+       unsigned bit_count, unsigned offset)
+{
+       DEBUG_IO("%d bits, offset %d", bit_count, offset);
+       assert(ctx->read_count + DIV_ROUND_UP(bit_count, 8) <= ctx->read_size);
+       bit_copy_queued(&ctx->read_queue, in, in_offset, ctx->read_buffer + ctx->read_count, offset,
+               bit_count);
+       ctx->read_count += DIV_ROUND_UP(bit_count, 8);
+       return bit_count;
+}
+
+int mpsse_clock_data_out(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset,
+       unsigned length, uint8_t mode)
+{
+       return mpsse_clock_data(ctx, out, out_offset, 0, 0, length, mode);
+}
+
+int mpsse_clock_data_in(struct mpsse_ctx *ctx, uint8_t *in, unsigned in_offset, unsigned length,
+       uint8_t mode)
+{
+       return mpsse_clock_data(ctx, 0, 0, in, in_offset, length, mode);
+}
+
+int mpsse_clock_data(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset, uint8_t *in,
+       unsigned in_offset, unsigned length, uint8_t mode)
+{
+       /* TODO: Fix MSB first modes */
+       DEBUG_IO("%s%s %d bits", in ? "in" : "", out ? "out" : "", length);
+       int retval = ERROR_OK;
+
+       /* TODO: On H chips, use command 0x8E/0x8F if in and out are both 0 */
+       if (out || (!out && !in))
+               mode |= 0x10;
+       if (in)
+               mode |= 0x20;
+
+       while (length > 0) {
+               /* Guarantee buffer space enough for a minimum size transfer */
+               if (buffer_write_space(ctx) + (length < 8) < (out ? 4 : 3)
+                   || (in && buffer_read_space(ctx) < 1))
+                       retval = mpsse_flush(ctx);
+
+               if (length < 8) {
+                       /* Transfer remaining bits in bit mode */
+                       buffer_write_byte(ctx, 0x02 | mode);
+                       buffer_write_byte(ctx, length - 1);
+                       if (out)
+                               out_offset += buffer_write(ctx, out, out_offset, length);
+                       if (in)
+                               in_offset += buffer_add_read(ctx, in, in_offset, length, 8 - length);
+                       if (!out && !in)
+                               buffer_write_byte(ctx, 0x00);
+                       length = 0;
+               } else {
+                       /* Byte transfer */
+                       unsigned this_bytes = length / 8;
+                       /* MPSSE command limit */
+                       if (this_bytes > 65536)
+                               this_bytes = 65536;
+                       /* Buffer space limit. We already made sure there's space for the minimum
+                        *transfer. */
+                       if (out && this_bytes + 3 > buffer_write_space(ctx))
+                               this_bytes = buffer_write_space(ctx) - 3;
+                       if (in && this_bytes > buffer_read_space(ctx))
+                               this_bytes = buffer_read_space(ctx);
+
+                       if (this_bytes > 0) {
+                               buffer_write_byte(ctx, mode);
+                               buffer_write_byte(ctx, (this_bytes - 1) & 0xff);
+                               buffer_write_byte(ctx, (this_bytes - 1) >> 8);
+                               if (out)
+                                       out_offset += buffer_write(ctx,
+                                                       out,
+                                                       out_offset,
+                                                       this_bytes * 8);
+                               if (in)
+                                       in_offset += buffer_add_read(ctx,
+                                                       in,
+                                                       in_offset,
+                                                       this_bytes * 8,
+                                                       0);
+                               if (!out && !in)
+                                       for (unsigned n = 0; n < this_bytes; n++)
+                                               buffer_write_byte(ctx, 0x00);
+                               length -= this_bytes * 8;
+                       }
+               }
+       }
+       return retval;
+}
+
+int mpsse_clock_tms_cs_out(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset,
+       unsigned length, bool tdi, uint8_t mode)
+{
+       return mpsse_clock_tms_cs(ctx, out, out_offset, 0, 0, length, tdi, mode);
+}
+
+int mpsse_clock_tms_cs(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset, uint8_t *in,
+       unsigned in_offset, unsigned length, bool tdi, uint8_t mode)
+{
+       DEBUG_IO("%sout %d bits, tdi=%d", in ? "in" : "", length, tdi);
+       assert(out);
+       int retval = ERROR_OK;
+
+       mode |= 0x42;
+       if (in)
+               mode |= 0x20;
+
+       while (length > 0) {
+               /* Guarantee buffer space enough for a minimum size transfer */
+               if (buffer_write_space(ctx) < 3 || (in && buffer_read_space(ctx) < 1))
+                       retval = mpsse_flush(ctx);
+
+               /* Byte transfer */
+               unsigned this_bits = length;
+               /* MPSSE command limit */
+               /* NOTE: there's a report of an FT2232 bug in this area, where shifting
+                * exactly 7 bits can make problems with TMS signaling for the last
+                * clock cycle:
+                *
+                * http://developer.intra2net.com/mailarchive/html/libftdi/2009/msg00292.html
+                */
+               if (this_bits > 7)
+                       this_bits = 7;
+
+               if (this_bits > 0) {
+                       buffer_write_byte(ctx, mode);
+                       buffer_write_byte(ctx, this_bits - 1);
+                       uint8_t data = 0;
+                       /* TODO: Fix MSB first, if allowed in MPSSE */
+                       bit_copy(&data, 0, out, out_offset, this_bits);
+                       out_offset += this_bits;
+                       buffer_write_byte(ctx, data | (tdi ? 0x80 : 0x00));
+                       if (in)
+                               in_offset += buffer_add_read(ctx,
+                                               in,
+                                               in_offset,
+                                               this_bits,
+                                               8 - this_bits);
+                       length -= this_bits;
+               }
+       }
+       return retval;
+}
+
+int mpsse_set_data_bits_low_byte(struct mpsse_ctx *ctx, uint8_t data, uint8_t dir)
+{
+       DEBUG_IO("-");
+       int retval = ERROR_OK;
+
+       if (buffer_write_space(ctx) < 3)
+               retval = mpsse_flush(ctx);
+
+       buffer_write_byte(ctx, 0x80);
+       buffer_write_byte(ctx, data);
+       buffer_write_byte(ctx, dir);
+
+       return retval;
+}
+
+int mpsse_set_data_bits_high_byte(struct mpsse_ctx *ctx, uint8_t data, uint8_t dir)
+{
+       DEBUG_IO("-");
+       int retval = ERROR_OK;
+
+       if (buffer_write_space(ctx) < 3)
+               retval = mpsse_flush(ctx);
+
+       buffer_write_byte(ctx, 0x82);
+       buffer_write_byte(ctx, data);
+       buffer_write_byte(ctx, dir);
+
+       return retval;
+}
+
+int mpsse_read_data_bits_low_byte(struct mpsse_ctx *ctx, uint8_t *data)
+{
+       DEBUG_IO("-");
+       int retval = ERROR_OK;
+
+       if (buffer_write_space(ctx) < 1)
+               retval = mpsse_flush(ctx);
+
+       buffer_write_byte(ctx, 0x81);
+       buffer_add_read(ctx, data, 0, 8, 0);
+
+       return retval;
+}
+
+int mpsse_read_data_bits_high_byte(struct mpsse_ctx *ctx, uint8_t *data)
+{
+       DEBUG_IO("-");
+       int retval = ERROR_OK;
+
+       if (buffer_write_space(ctx) < 1)
+               retval = mpsse_flush(ctx);
+
+       buffer_write_byte(ctx, 0x83);
+       buffer_add_read(ctx, data, 0, 8, 0);
+
+       return retval;
+}
+
+static int single_byte_boolean_helper(struct mpsse_ctx *ctx, bool var, uint8_t val_if_true,
+       uint8_t val_if_false)
+{
+       int retval = ERROR_OK;
+
+       if (buffer_write_space(ctx) < 1)
+               retval = mpsse_flush(ctx);
+
+       buffer_write_byte(ctx, var ? val_if_true : val_if_false);
+
+       return retval;
+}
+
+int mpsse_loopback_config(struct mpsse_ctx *ctx, bool enable)
+{
+       LOG_DEBUG("%s", enable ? "on" : "off");
+       return single_byte_boolean_helper(ctx, enable, 0x84, 0x85);
+}
+
+int mpsse_set_divisor(struct mpsse_ctx *ctx, uint16_t divisor)
+{
+       LOG_DEBUG("%d", divisor);
+       int retval = ERROR_OK;
+
+       if (buffer_write_space(ctx) < 3)
+               retval = mpsse_flush(ctx);
+
+       buffer_write_byte(ctx, 0x86);
+       buffer_write_byte(ctx, divisor & 0xff);
+       buffer_write_byte(ctx, divisor >> 8);
+
+       return retval;
+}
+
+int mpsse_divide_by_5_config(struct mpsse_ctx *ctx, bool enable)
+{
+       if (!mpsse_is_high_speed(ctx))
+               return ERROR_FAIL;
+
+       LOG_DEBUG("%s", enable ? "on" : "off");
+
+       return single_byte_boolean_helper(ctx, enable, 0x8b, 0x8a);
+}
+
+int mpsse_rtck_config(struct mpsse_ctx *ctx, bool enable)
+{
+       if (!mpsse_is_high_speed(ctx))
+               return ERROR_FAIL;
+
+       LOG_DEBUG("%s", enable ? "on" : "off");
+
+       return single_byte_boolean_helper(ctx, enable, 0x96, 0x97);
+}
+
+int mpsse_set_frequency(struct mpsse_ctx *ctx, int frequency)
+{
+       LOG_DEBUG("target %d Hz", frequency);
+       assert(frequency >= 0);
+       int base_clock;
+
+       if (frequency == 0)
+               return mpsse_rtck_config(ctx, true);
+
+       mpsse_rtck_config(ctx, false); /* just try */
+
+       if (frequency > 60000000 / 2 / 65536 && mpsse_is_high_speed(ctx)) {
+               int retval = mpsse_divide_by_5_config(ctx, false);
+               if (retval != ERROR_OK)
+                       return retval;
+               base_clock = 60000000;
+       } else {
+               mpsse_divide_by_5_config(ctx, true); /* just try */
+               base_clock = 12000000;
+       }
+
+       int divisor = (base_clock / 2 + frequency - 1) / frequency - 1;
+       if (divisor > 65535)
+               divisor = 65535;
+       assert(divisor >= 0);
+
+       int retval = mpsse_set_divisor(ctx, divisor);
+       if (retval != ERROR_OK)
+               return retval;
+
+       frequency = base_clock / 2 / (1 + divisor);
+       LOG_DEBUG("actually %d Hz", frequency);
+
+       return frequency;
+}
+
+/* Context needed by the callbacks */
+struct transfer_result {
+       struct mpsse_ctx *ctx;
+       bool done;
+       unsigned transferred;
+};
+
+static LIBUSB_CALL void read_cb(struct libusb_transfer *transfer)
+{
+       struct transfer_result *res = (struct transfer_result *)transfer->user_data;
+       struct mpsse_ctx *ctx = res->ctx;
+
+       unsigned packet_size = ctx->max_packet_size;
+
+       DEBUG_PRINT_BUF(transfer->buffer, transfer->actual_length);
+
+       /* Strip the two status bytes sent at the beginning of each USB packet
+        * while copying the chunk buffer to the read buffer */
+       unsigned num_packets = DIV_ROUND_UP(transfer->actual_length, packet_size);
+       unsigned chunk_remains = transfer->actual_length;
+       for (unsigned i = 0; i < num_packets && chunk_remains > 2; i++) {
+               unsigned this_size = packet_size - 2;
+               if (this_size > chunk_remains - 2)
+                       this_size = chunk_remains - 2;
+               if (this_size > ctx->read_count - res->transferred)
+                       this_size = ctx->read_count - res->transferred;
+               memcpy(ctx->read_buffer + res->transferred,
+                       ctx->read_chunk + packet_size * i + 2,
+                       this_size);
+               res->transferred += this_size;
+               chunk_remains -= this_size + 2;
+               if (res->transferred == ctx->read_count) {
+                       res->done = true;
+                       break;
+               }
+       }
+
+       DEBUG_IO("raw chunk %d, transferred %d of %d", transfer->actual_length, res->transferred,
+               ctx->read_count);
+
+       if (!res->done)
+               if (libusb_submit_transfer(transfer) != LIBUSB_SUCCESS)
+                       res->done = true;
+}
+
+static LIBUSB_CALL void write_cb(struct libusb_transfer *transfer)
+{
+       struct transfer_result *res = (struct transfer_result *)transfer->user_data;
+       struct mpsse_ctx *ctx = res->ctx;
+
+       res->transferred += transfer->actual_length;
+
+       DEBUG_IO("transferred %d of %d", res->transferred, ctx->write_count);
+
+       DEBUG_PRINT_BUF(transfer->buffer, transfer->actual_length);
+
+       if (res->transferred == ctx->write_count)
+               res->done = true;
+       else {
+               transfer->length = ctx->write_count - res->transferred;
+               transfer->buffer = ctx->write_buffer + res->transferred;
+               if (libusb_submit_transfer(transfer) != LIBUSB_SUCCESS)
+                       res->done = true;
+       }
+}
+
+int mpsse_flush(struct mpsse_ctx *ctx)
+{
+       DEBUG_IO("write %d%s, read %d", ctx->write_count, ctx->read_count ? "+1" : "",
+                       ctx->read_count);
+       assert(ctx->write_count > 0 || ctx->read_count == 0); /* No read data without write data */
+       int retval = ERROR_OK;
+
+       if (ctx->write_count == 0)
+               return retval;
+
+       struct libusb_transfer *read_transfer = 0;
+       struct transfer_result read_result = { .ctx = ctx, .done = true };
+       if (ctx->read_count) {
+               buffer_write_byte(ctx, 0x87); /* SEND_IMMEDIATE */
+               read_result.done = false;
+               read_transfer = libusb_alloc_transfer(0);
+               libusb_fill_bulk_transfer(read_transfer, ctx->usb_dev, ctx->in_ep, ctx->read_chunk,
+                       ctx->read_chunk_size, read_cb, &read_result,
+                       ctx->usb_read_timeout);
+               retval = libusb_submit_transfer(read_transfer);
+       }
+
+       struct transfer_result write_result = { .ctx = ctx, .done = false };
+       struct libusb_transfer *write_transfer = libusb_alloc_transfer(0);
+       libusb_fill_bulk_transfer(write_transfer, ctx->usb_dev, ctx->out_ep, ctx->write_buffer,
+               ctx->write_count, write_cb, &write_result, ctx->usb_write_timeout);
+       retval = libusb_submit_transfer(write_transfer);
+
+       /* Polling loop, more or less taken from libftdi */
+       while (!write_result.done || !read_result.done) {
+               retval = libusb_handle_events(ctx->usb_ctx);
+               keep_alive();
+               if (retval != LIBUSB_SUCCESS && retval != LIBUSB_ERROR_INTERRUPTED) {
+                       libusb_cancel_transfer(write_transfer);
+                       if (read_transfer)
+                               libusb_cancel_transfer(read_transfer);
+                       while (!write_result.done || !read_result.done)
+                               if (libusb_handle_events(ctx->usb_ctx) != LIBUSB_SUCCESS)
+                                       break;
+               }
+       }
+
+       if (retval != LIBUSB_SUCCESS) {
+               LOG_ERROR("libusb_handle_events() failed with %d", retval);
+               retval = ERROR_FAIL;
+       } else if (write_result.transferred < ctx->write_count) {
+               LOG_ERROR("ftdi device did not accept all data: %d, tried %d",
+                       write_result.transferred,
+                       ctx->write_count);
+               retval = ERROR_FAIL;
+       } else if (read_result.transferred < ctx->read_count) {
+               LOG_ERROR("ftdi device did not return all data: %d, expected %d",
+                       read_result.transferred,
+                       ctx->read_count);
+               retval = ERROR_FAIL;
+       } else if (ctx->read_count) {
+               ctx->write_count = 0;
+               ctx->read_count = 0;
+               bit_copy_execute(&ctx->read_queue);
+               retval = ERROR_OK;
+       } else {
+               ctx->write_count = 0;
+               bit_copy_discard(&ctx->read_queue);
+               retval = ERROR_OK;
+       }
+
+       libusb_free_transfer(write_transfer);
+       if (read_transfer)
+               libusb_free_transfer(read_transfer);
+
+       if (retval != ERROR_OK)
+               mpsse_purge(ctx);
+
+       return retval;
+}
diff --git a/src/jtag/drivers/mpsse.h b/src/jtag/drivers/mpsse.h
new file mode 100644 (file)
index 0000000..766a215
--- /dev/null
@@ -0,0 +1,79 @@
+/**************************************************************************
+ *   Copyright (C) 2012 by Andreas Fritiofson                              *
+ *   andreas.fritiofson@gmail.com                                          *
+ *                                                                         *
+ *   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     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+
+#ifndef MPSSE_H_
+#define MPSSE_H_
+
+#include <stdbool.h>
+#include "helper/binarybuffer.h"
+
+/* Mode flags */
+#define POS_EDGE_OUT 0x00
+#define NEG_EDGE_OUT 0x01
+#define POS_EDGE_IN 0x00
+#define NEG_EDGE_IN 0x04
+#define MSB_FIRST 0x00
+#define LSB_FIRST 0x08
+
+enum ftdi_chip_type {
+       TYPE_FT2232C,
+       TYPE_FT2232H,
+       TYPE_FT4232H,
+};
+
+struct mpsse_ctx;
+
+/* Device handling */
+struct mpsse_ctx *mpsse_open(const uint16_t *vid, const uint16_t *pid, const char *description,
+       const char *serial, int channel);
+void mpsse_close(struct mpsse_ctx *ctx);
+bool mpsse_is_high_speed(struct mpsse_ctx *ctx);
+
+/* Command queuing. These correspond to the MPSSE commands with the same names, but no need to care
+ * about bit/byte transfer or data length limitation. Read data is guaranteed to be available only
+ * after the following mpsse_flush(). */
+int mpsse_clock_data_out(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset,
+                        unsigned length, uint8_t mode);
+int mpsse_clock_data_in(struct mpsse_ctx *ctx, uint8_t *in, unsigned in_offset, unsigned length,
+                       uint8_t mode);
+int mpsse_clock_data(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset, uint8_t *in,
+                    unsigned in_offset, unsigned length, uint8_t mode);
+int mpsse_clock_tms_cs_out(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset,
+                          unsigned length, bool tdi, uint8_t mode);
+int mpsse_clock_tms_cs(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset, uint8_t *in,
+                      unsigned in_offset, unsigned length, bool tdi, uint8_t mode);
+int mpsse_set_data_bits_low_byte(struct mpsse_ctx *ctx, uint8_t data, uint8_t dir);
+int mpsse_set_data_bits_high_byte(struct mpsse_ctx *ctx, uint8_t data, uint8_t dir);
+int mpsse_read_data_bits_low_byte(struct mpsse_ctx *ctx, uint8_t *data);
+int mpsse_read_data_bits_high_byte(struct mpsse_ctx *ctx, uint8_t *data);
+int mpsse_loopback_config(struct mpsse_ctx *ctx, bool enable);
+int mpsse_set_divisor(struct mpsse_ctx *ctx, uint16_t divisor);
+int mpsse_divide_by_5_config(struct mpsse_ctx *ctx, bool enable);
+int mpsse_rtck_config(struct mpsse_ctx *ctx, bool enable);
+
+/* Helper to set frequency in Hertz. Returns actual realizable frequency or negative error.
+ * Frequency 0 means RTCK. */
+int mpsse_set_frequency(struct mpsse_ctx *ctx, int frequency);
+
+/* Queue handling */
+int mpsse_flush(struct mpsse_ctx *ctx);
+void mpsse_purge(struct mpsse_ctx *ctx);
+
+#endif /* MPSSE_H_ */