sr_usb_close(usb);
return ret;
}
+ /* This delay appears to be necessary for reliable operation. */
+ g_usleep(30 * 1000);
sdi->status = SR_ST_ACTIVE;
devc->active_fpga_config = FPGA_NOCONF;
+ devc->short_transfer_quirk = FALSE;
devc->state = STATE_IDLE;
ret = (*devc->model->apply_fpga_config)(sdi);
if (ret != SR_OK) {
sdi->status = SR_ST_INACTIVE;
sr_usb_close(usb);
+ return ret;
}
- return ret;
+ if (devc->short_transfer_quirk)
+ sr_warn("Short transfer quirk detected! "
+ "Memory reads will be slow.");
+ return SR_OK;
}
/* Shutdown and close device.
}
SR_PRIV int lwla_receive_reply(const struct sr_usb_dev_inst *usb,
- uint32_t *reply, int reply_len, int expect_len)
+ void *reply, int buf_size, int *xfer_len)
{
int ret;
- int xfer_len;
- if (!usb || !reply || reply_len <= 0)
+ if (!usb || !reply || buf_size <= 0)
return SR_ERR_BUG;
- xfer_len = 0;
- ret = libusb_bulk_transfer(usb->devhdl, EP_REPLY,
- (unsigned char *)reply, reply_len * 4,
- &xfer_len, USB_TIMEOUT_MS);
+ ret = libusb_bulk_transfer(usb->devhdl, EP_REPLY, reply, buf_size,
+ xfer_len, USB_TIMEOUT_MS);
if (ret != 0) {
sr_dbg("Failed to receive reply: %s.", libusb_error_name(ret));
return SR_ERR;
}
- if (xfer_len != expect_len * 4) {
- sr_dbg("Failed to receive reply: incorrect length %d != %d.",
- xfer_len, expect_len * 4);
- return SR_ERR;
- }
return SR_OK;
}
SR_PRIV int lwla_read_reg(const struct sr_usb_dev_inst *usb,
uint16_t reg, uint32_t *value)
{
+ int xfer_len;
int ret;
uint16_t command[2];
uint32_t reply[128]; /* full EP buffer to avoid overflows */
command[1] = LWLA_WORD(reg);
ret = lwla_send_command(usb, command, ARRAY_SIZE(command));
-
if (ret != SR_OK)
return ret;
- ret = lwla_receive_reply(usb, reply, ARRAY_SIZE(reply), 1);
+ ret = lwla_receive_reply(usb, reply, sizeof(reply), &xfer_len);
+ if (ret != SR_OK)
+ return ret;
- if (ret == SR_OK)
- *value = LWLA_TO_UINT32(reply[0]);
+ if (xfer_len != 4) {
+ sr_dbg("Invalid register read response of length %d.",
+ xfer_len);
+ return SR_ERR;
+ }
+ *value = LWLA_TO_UINT32(reply[0]);
- return ret;
+ return SR_OK;
}
SR_PRIV int lwla_write_reg(const struct sr_usb_dev_inst *usb,
const uint16_t *command, int cmd_len);
SR_PRIV int lwla_receive_reply(const struct sr_usb_dev_inst *usb,
- uint32_t *reply, int reply_len, int expect_len);
+ void *reply, int buf_size, int *xfer_len);
SR_PRIV int lwla_read_reg(const struct sr_usb_dev_inst *usb,
uint16_t reg, uint32_t *value);
/* Capture memory read start address.
*/
-#define READ_START_ADDR 2
+#define READ_START_ADDR 2
/* Number of device memory units (32 bit) to read at a time.
*/
-#define READ_CHUNK_LEN32 250
+#define READ_CHUNK_LEN 250
/** LWLA1016 register addresses.
*/
acq->mem_addr_done += wi;
}
+/* Check whether we can receive responses of more than 64 bytes.
+ * The FX2 firmware of the LWLA1016 has a bug in the reset logic which
+ * sometimes causes the response endpoint to be limited to transfers of
+ * 64 bytes at a time, instead of the expected 2*512 bytes. The problem
+ * can be worked around by never requesting more than 64 bytes.
+ * This quirk manifests itself only under certain conditions, and some
+ * users seem to see it more frequently than others. Detect it here in
+ * order to avoid paying the penalty unnecessarily.
+ */
+static int test_read_memory(const struct sr_dev_inst *sdi,
+ unsigned int start, unsigned int count)
+{
+ struct dev_context *devc;
+ struct sr_usb_dev_inst *usb;
+ unsigned int i;
+ int xfer_len;
+ int ret;
+ uint16_t command[5];
+ unsigned char reply[512];
+
+ devc = sdi->priv;
+ usb = sdi->conn;
+
+ command[0] = LWLA_WORD(CMD_READ_MEM32);
+ command[1] = LWLA_WORD_0(start);
+ command[2] = LWLA_WORD_1(start);
+ command[3] = LWLA_WORD_0(count);
+ command[4] = LWLA_WORD_1(count);
+
+ ret = lwla_send_command(usb, command, ARRAY_SIZE(command));
+ if (ret != SR_OK)
+ return ret;
+
+ ret = lwla_receive_reply(usb, reply, sizeof(reply), &xfer_len);
+ if (ret != SR_OK)
+ return ret;
+
+ devc->short_transfer_quirk = (xfer_len == 64);
+
+ for (i = xfer_len; i < 4 * count && xfer_len == 64; i += xfer_len) {
+ ret = lwla_receive_reply(usb, reply, sizeof(reply), &xfer_len);
+ if (ret != SR_OK)
+ return ret;
+ }
+ if (i != 4 * count) {
+ sr_err("Invalid read response of unexpected length %d.",
+ xfer_len);
+ return SR_ERR;
+ }
+ return SR_OK;
+}
+
/* Select and transfer FPGA bitstream for the current configuration.
*/
static int apply_fpga_config(const struct sr_dev_inst *sdi)
*/
static int device_init_check(const struct sr_dev_inst *sdi)
{
+ static const struct regval mem_reset[] = {
+ {REG_MEM_CTRL, MEM_CTRL_RESET},
+ {REG_MEM_CTRL, 0},
+ };
uint32_t value;
int ret;
+ const unsigned int test_count = 24;
+
ret = lwla_read_reg(sdi->conn, REG_TEST_ID, &value);
if (ret != SR_OK)
return ret;
sr_err("Received invalid test word 0x%08X.", value);
return SR_ERR;
}
- return SR_OK;
+
+ ret = lwla_write_regs(sdi->conn, mem_reset, ARRAY_SIZE(mem_reset));
+ if (ret != SR_OK)
+ return ret;
+
+ ret = test_read_memory(sdi, 0, test_count);
+ if (ret != SR_OK)
+ return ret;
+ /*
+ * Issue another read request or the device will stall, for whatever
+ * reason. This happens both with and without the short transfer quirk.
+ */
+ return test_read_memory(sdi, test_count, test_count);
}
static int setup_acquisition(const struct sr_dev_inst *sdi)
{
struct dev_context *devc;
struct acquisition_state *acq;
- unsigned int count;
+ unsigned int chunk_len, count;
devc = sdi->priv;
acq = devc->acquisition;
lwla_queue_regval(acq, REG_CAP_COUNT, 0);
break;
case STATE_READ_REQUEST:
- count = MIN(READ_CHUNK_LEN32,
- acq->mem_addr_stop - acq->mem_addr_next);
+ /* Limit reads to 16 device words (64 bytes) at a time if the
+ * device firmware has the short transfer quirk. */
+ chunk_len = (devc->short_transfer_quirk) ? 16 : READ_CHUNK_LEN;
+ count = MIN(chunk_len, acq->mem_addr_stop - acq->mem_addr_next);
acq->xfer_buf_out[0] = LWLA_WORD(CMD_READ_MEM32);
acq->xfer_buf_out[1] = LWLA_WORD_0(acq->mem_addr_next);
/* Capture memory read start address.
*/
-#define READ_START_ADDR 4
+#define READ_START_ADDR 4
/* Number of device memory units (36 bit) to read at a time. Slices of 8
* consecutive 36-bit words are mapped to 9 32-bit words each, so the chunk
* a time. So far, it appears safe to increase this to 224 words (28 slices,
* 1008 bytes), thus making the most of two 512 byte buffers.
*/
-#define READ_CHUNK_LEN36 (28 * 8)
+#define READ_CHUNK_LEN (28 * 8)
/* Bit mask for the RLE repeat-count-follows flag.
*/
acq->mem_addr_done += wi;
}
+/* Check whether we can receive responses of more than 64 bytes.
+ * The FX2 firmware of the LWLA1034 has a bug in the reset logic which
+ * sometimes causes the response endpoint to be limited to transfers of
+ * 64 bytes at a time, instead of the expected 2*512 bytes. The problem
+ * can be worked around by never requesting more than 64 bytes.
+ * This quirk manifests itself only under certain conditions, and some
+ * users seem to see it more frequently than others. Detect it here in
+ * order to avoid paying the penalty unnecessarily.
+ */
+static int detect_short_transfer_quirk(const struct sr_dev_inst *sdi)
+{
+ struct dev_context *devc;
+ struct sr_usb_dev_inst *usb;
+ int xfer_len;
+ int ret;
+ uint16_t command[3];
+ unsigned char buf[512];
+
+ const int lreg_count = 10;
+
+ devc = sdi->priv;
+ usb = sdi->conn;
+
+ command[0] = LWLA_WORD(CMD_READ_LREGS);
+ command[1] = LWLA_WORD(0);
+ command[2] = LWLA_WORD(lreg_count);
+
+ ret = lwla_send_command(usb, command, ARRAY_SIZE(command));
+ if (ret != SR_OK)
+ return ret;
+
+ ret = lwla_receive_reply(usb, buf, sizeof(buf), &xfer_len);
+ if (ret != SR_OK)
+ return ret;
+
+ devc->short_transfer_quirk = (xfer_len == 64);
+
+ if (xfer_len == 8 * lreg_count)
+ return SR_OK;
+
+ if (xfer_len == 64) {
+ /* Drain the tailing portion of the split transfer. */
+ ret = lwla_receive_reply(usb, buf, sizeof(buf), &xfer_len);
+ if (ret != SR_OK)
+ return ret;
+
+ if (xfer_len == 8 * lreg_count - 64)
+ return SR_OK;
+ }
+ sr_err("Received response of unexpected length %d.", xfer_len);
+
+ return SR_ERR;
+}
+
/* Select and transfer FPGA bitstream for the current configuration.
*/
static int apply_fpga_config(const struct sr_dev_inst *sdi)
sr_err("Received invalid test word 0x%016" PRIX64 ".", value);
return SR_ERR;
}
- return SR_OK;
+
+ return detect_short_transfer_quirk(sdi);
}
/* Set up the device in preparation for an acquisition session.
{
struct dev_context *devc;
struct acquisition_state *acq;
- unsigned int count;
+ unsigned int chunk_len, remaining, count;
devc = sdi->priv;
acq = devc->acquisition;
lwla_queue_regval(acq, REG_MEM_FILL, 0);
break;
case STATE_READ_REQUEST:
+ /* Limit reads to 8 device words (36 bytes) at a time if the
+ * device firmware has the short transfer quirk. */
+ chunk_len = (devc->short_transfer_quirk) ? 8 : READ_CHUNK_LEN;
/* Always read a multiple of 8 device words. */
- count = MIN(READ_CHUNK_LEN36, acq->mem_addr_stop
- - acq->mem_addr_next + 7) / 8 * 8;
+ remaining = (acq->mem_addr_stop - acq->mem_addr_next + 7) / 8 * 8;
+ count = MIN(chunk_len, remaining);
acq->xfer_buf_out[0] = LWLA_WORD(CMD_READ_MEM36);
acq->xfer_buf_out[1] = LWLA_WORD_0(acq->mem_addr_next);
const struct model_info *model; /* device model descriptor */
struct acquisition_state *acquisition; /* running capture state */
int active_fpga_config; /* FPGA configuration index */
+ gboolean short_transfer_quirk; /* 64 bytes response limit */
enum protocol_state state; /* async protocol state */
gboolean cancel_requested; /* stop after current transfer */