X-Git-Url: https://sigrok.org/gitweb/?p=libsigrok.git;a=blobdiff_plain;f=src%2Fhardware%2Fasix-sigma%2Fprotocol.c;h=fe90274f22c6ef557fce15c9d0434be97e78afdb;hp=98cfce7a185b1b4dd45a2940b372a04b227a5fd2;hb=5e78a56481769db6ffe9b9fd392d71be3fcf0319;hpb=85c032e48553458b43d0eb8315a7587abee4493f diff --git a/src/hardware/asix-sigma/protocol.c b/src/hardware/asix-sigma/protocol.c index 98cfce7a..fe90274f 100644 --- a/src/hardware/asix-sigma/protocol.c +++ b/src/hardware/asix-sigma/protocol.c @@ -47,19 +47,16 @@ SR_PRIV const uint64_t samplerates[] = { SR_PRIV const size_t samplerates_count = ARRAY_SIZE(samplerates); -static const char sigma_firmware_files[][24] = { - /* 50 MHz, supports 8 bit fractions */ - "asix-sigma-50.fw", - /* 100 MHz */ - "asix-sigma-100.fw", - /* 200 MHz */ - "asix-sigma-200.fw", - /* Synchronous clock from pin */ - "asix-sigma-50sync.fw", - /* Frequency counter */ - "asix-sigma-phasor.fw", +static const char *firmware_files[] = { + "asix-sigma-50.fw", /* Up to 50MHz sample rate, 8bit divider. */ + "asix-sigma-100.fw", /* 100MHz sample rate, fixed. */ + "asix-sigma-200.fw", /* 200MHz sample rate, fixed. */ + "asix-sigma-50sync.fw", /* Synchronous clock from external pin. */ + "asix-sigma-phasor.fw", /* Frequency counter. */ }; +#define SIGMA_FIRMWARE_SIZE_LIMIT (256 * 1024) + static int sigma_read(void *buf, size_t size, struct dev_context *devc) { int ret; @@ -78,12 +75,11 @@ static int sigma_write(void *buf, size_t size, struct dev_context *devc) int ret; ret = ftdi_write_data(&devc->ftdic, (unsigned char *)buf, size); - if (ret < 0) { + if (ret < 0) sr_err("ftdi_write_data failed: %s", ftdi_get_error_string(&devc->ftdic)); - } else if ((size_t) ret != size) { + else if ((size_t) ret != size) sr_err("ftdi_write_data did not complete write."); - } return ret; } @@ -135,30 +131,21 @@ static int sigma_read_register(uint8_t reg, uint8_t *data, size_t len, return sigma_read(data, len, devc); } -static uint8_t sigma_get_register(uint8_t reg, struct dev_context *devc) -{ - uint8_t value; - - if (1 != sigma_read_register(reg, &value, 1, devc)) { - sr_err("sigma_get_register: 1 byte expected"); - return 0; - } - - return value; -} - static int sigma_read_pos(uint32_t *stoppos, uint32_t *triggerpos, struct dev_context *devc) { + /* + * Read 6 registers starting at trigger position LSB. + * Which yields two 24bit counter values. + */ uint8_t buf[] = { REG_ADDR_LOW | READ_TRIGGER_POS_LOW, - - REG_READ_ADDR | NEXT_REG, - REG_READ_ADDR | NEXT_REG, - REG_READ_ADDR | NEXT_REG, - REG_READ_ADDR | NEXT_REG, - REG_READ_ADDR | NEXT_REG, - REG_READ_ADDR | NEXT_REG, + REG_READ_ADDR | REG_ADDR_INC, + REG_READ_ADDR | REG_ADDR_INC, + REG_READ_ADDR | REG_ADDR_INC, + REG_READ_ADDR | REG_ADDR_INC, + REG_READ_ADDR | REG_ADDR_INC, + REG_READ_ADDR | REG_ADDR_INC, }; uint8_t result[6]; @@ -169,11 +156,25 @@ static int sigma_read_pos(uint32_t *stoppos, uint32_t *triggerpos, *triggerpos = result[0] | (result[1] << 8) | (result[2] << 16); *stoppos = result[3] | (result[4] << 8) | (result[5] << 16); - /* Not really sure why this must be done, but according to spec. */ + /* + * These "position" values point to after the event (end of + * capture data, trigger condition matched). This is why they + * get decremented here. Sample memory consists of 512-byte + * chunks with meta data in the upper 64 bytes. Thus when the + * decrements takes us into this upper part of the chunk, then + * further move backwards to the end of the chunk's data part. + * + * TODO Re-consider the above comment's validity. It's true + * that a 1024byte row contains 512 u16 entities, of which 64 + * are timestamps and 448 are events with sample data. It's not + * true that 64bytes of metadata reside at the top of a 512byte + * block in a row. + * + * TODO Use ROW_MASK and CLUSTERS_PER_ROW here? + */ if ((--*stoppos & 0x1ff) == 0x1ff) *stoppos -= 64; - - if ((*--triggerpos & 0x1ff) == 0x1ff) + if ((--*triggerpos & 0x1ff) == 0x1ff) *triggerpos -= 64; return 1; @@ -182,33 +183,38 @@ static int sigma_read_pos(uint32_t *stoppos, uint32_t *triggerpos, static int sigma_read_dram(uint16_t startchunk, size_t numchunks, uint8_t *data, struct dev_context *devc) { - size_t i; uint8_t buf[4096]; - int idx = 0; + int idx; + size_t chunk; + int sel; + gboolean is_last; - /* Send the startchunk. Index start with 1. */ - buf[0] = startchunk >> 8; - buf[1] = startchunk & 0xff; - sigma_write_register(WRITE_MEMROW, buf, 2, devc); + /* Communicate DRAM start address (memory row, aka samples line). */ + idx = 0; + buf[idx++] = startchunk >> 8; + buf[idx++] = startchunk & 0xff; + sigma_write_register(WRITE_MEMROW, buf, idx, devc); - /* Read the DRAM. */ + /* + * Access DRAM content. Fetch from DRAM to FPGA's internal RAM, + * then transfer via USB. Interleave the FPGA's DRAM access and + * USB transfer, use alternating buffers (0/1) in the process. + */ + idx = 0; buf[idx++] = REG_DRAM_BLOCK; buf[idx++] = REG_DRAM_WAIT_ACK; - - for (i = 0; i < numchunks; i++) { - /* Alternate bit to copy from DRAM to cache. */ - if (i != (numchunks - 1)) - buf[idx++] = REG_DRAM_BLOCK | (((i + 1) % 2) << 4); - - buf[idx++] = REG_DRAM_BLOCK_DATA | ((i % 2) << 4); - - if (i != (numchunks - 1)) + for (chunk = 0; chunk < numchunks; chunk++) { + sel = chunk % 2; + is_last = chunk == numchunks - 1; + if (!is_last) + buf[idx++] = REG_DRAM_BLOCK | REG_DRAM_SEL_BOOL(!sel); + buf[idx++] = REG_DRAM_BLOCK_DATA | REG_DRAM_SEL_BOOL(sel); + if (!is_last) buf[idx++] = REG_DRAM_WAIT_ACK; } - sigma_write(buf, idx, devc); - return sigma_read(data, numchunks * CHUNK_SIZE, devc); + return sigma_read(data, numchunks * ROW_LENGTH_BYTES, devc); } /* Upload trigger look-up tables to Sigma. */ @@ -258,43 +264,83 @@ SR_PRIV int sigma_write_trigger_lut(struct triggerlut *lut, struct dev_context * if (lut->m1d[3] & bit) tmp[1] |= 0x80; - sigma_write_register(WRITE_TRIGGER_SELECT0, tmp, sizeof(tmp), + sigma_write_register(WRITE_TRIGGER_SELECT, tmp, sizeof(tmp), devc); - sigma_set_register(WRITE_TRIGGER_SELECT1, 0x30 | i, devc); + sigma_set_register(WRITE_TRIGGER_SELECT2, 0x30 | i, devc); } /* Send the parameters */ - sigma_write_register(WRITE_TRIGGER_SELECT0, (uint8_t *) &lut->params, + sigma_write_register(WRITE_TRIGGER_SELECT, (uint8_t *) &lut->params, sizeof(lut->params), devc); return SR_OK; } -SR_PRIV void sigma_clear_helper(void *priv) -{ - struct dev_context *devc; - - devc = priv; - - ftdi_deinit(&devc->ftdic); -} +/* + * See Xilinx UG332 for Spartan-3 FPGA configuration. The SIGMA device + * uses FTDI bitbang mode for netlist download in slave serial mode. + * (LATER: The OMEGA device's cable contains a more capable FTDI chip + * and uses MPSSE mode for bitbang. -- Can we also use FT232H in FT245 + * compatible bitbang mode? For maximum code re-use and reduced libftdi + * dependency? See section 3.5.5 of FT232H: D0 clk, D1 data (out), D2 + * data (in), D3 select, D4-7 GPIOL. See section 3.5.7 for MCU FIFO.) + * + * 750kbps rate (four times the speed of sigmalogan) works well for + * netlist download. All pins except INIT_B are output pins during + * configuration download. + * + * Some pins are inverted as a byproduct of level shifting circuitry. + * That's why high CCLK level (from the cable's point of view) is idle + * from the FPGA's perspective. + * + * The vendor's literature discusses a "suicide sequence" which ends + * regular FPGA execution and should be sent before entering bitbang + * mode and sending configuration data. Set D7 and toggle D2, D3, D4 + * a few times. + */ +#define BB_PIN_CCLK (1 << 0) /* D0, CCLK */ +#define BB_PIN_PROG (1 << 1) /* D1, PROG */ +#define BB_PIN_D2 (1 << 2) /* D2, (part of) SUICIDE */ +#define BB_PIN_D3 (1 << 3) /* D3, (part of) SUICIDE */ +#define BB_PIN_D4 (1 << 4) /* D4, (part of) SUICIDE (unused?) */ +#define BB_PIN_INIT (1 << 5) /* D5, INIT, input pin */ +#define BB_PIN_DIN (1 << 6) /* D6, DIN */ +#define BB_PIN_D7 (1 << 7) /* D7, (part of) SUICIDE */ + +#define BB_BITRATE (750 * 1000) +#define BB_PINMASK (0xff & ~BB_PIN_INIT) /* - * Configure the FPGA for bitbang mode. - * This sequence is documented in section 2. of the ASIX Sigma programming - * manual. This sequence is necessary to configure the FPGA in the Sigma - * into Bitbang mode, in which it can be programmed with the firmware. + * Initiate slave serial mode for configuration download. Which is done + * by pulsing PROG_B and sensing INIT_B. Make sure CCLK is idle before + * initiating the configuration download. Run a "suicide sequence" first + * to terminate the regular FPGA operation before reconfiguration. */ static int sigma_fpga_init_bitbang(struct dev_context *devc) { uint8_t suicide[] = { - 0x84, 0x84, 0x88, 0x84, 0x88, 0x84, 0x88, 0x84, + BB_PIN_D7 | BB_PIN_D2, + BB_PIN_D7 | BB_PIN_D2, + BB_PIN_D7 | BB_PIN_D3, + BB_PIN_D7 | BB_PIN_D2, + BB_PIN_D7 | BB_PIN_D3, + BB_PIN_D7 | BB_PIN_D2, + BB_PIN_D7 | BB_PIN_D3, + BB_PIN_D7 | BB_PIN_D2, }; uint8_t init_array[] = { - 0x01, 0x03, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01, - 0x01, 0x01, + BB_PIN_CCLK, + BB_PIN_CCLK | BB_PIN_PROG, + BB_PIN_CCLK | BB_PIN_PROG, + BB_PIN_CCLK, + BB_PIN_CCLK, + BB_PIN_CCLK, + BB_PIN_CCLK, + BB_PIN_CCLK, + BB_PIN_CCLK, + BB_PIN_CCLK, }; - int i, ret, timeout = (10 * 1000); + int retries, ret; uint8_t data; /* Section 2. part 1), do the FPGA suicide. */ @@ -303,19 +349,18 @@ static int sigma_fpga_init_bitbang(struct dev_context *devc) sigma_write(suicide, sizeof(suicide), devc); sigma_write(suicide, sizeof(suicide), devc); - /* Section 2. part 2), do pulse on D1. */ + /* Section 2. part 2), pulse PROG. */ sigma_write(init_array, sizeof(init_array), devc); ftdi_usb_purge_buffers(&devc->ftdic); - /* Wait until the FPGA asserts D6/INIT_B. */ - for (i = 0; i < timeout; i++) { + /* Wait until the FPGA asserts INIT_B. */ + retries = 10; + while (retries--) { ret = sigma_read(&data, 1, devc); if (ret < 0) return ret; - /* Test if pin D6 got asserted. */ - if (data & (1 << 5)) - return 0; - /* The D6 was not asserted yet, wait a bit. */ + if (data & BB_PIN_INIT) + return SR_OK; g_usleep(10 * 1000); } @@ -327,41 +372,49 @@ static int sigma_fpga_init_bitbang(struct dev_context *devc) */ static int sigma_fpga_init_la(struct dev_context *devc) { - /* Initialize the logic analyzer mode. */ + /* + * TODO Construct the sequence at runtime? Such that request data + * and response check values will match more apparently? + */ + uint8_t mode_regval = WMR_SDRAMINIT; uint8_t logic_mode_start[] = { + /* Read ID register. */ REG_ADDR_LOW | (READ_ID & 0xf), - REG_ADDR_HIGH | (READ_ID >> 8), - REG_READ_ADDR, /* Read ID register. */ + REG_ADDR_HIGH | (READ_ID >> 4), + REG_READ_ADDR, + /* Write 0x55 to scratch register, read back. */ REG_ADDR_LOW | (WRITE_TEST & 0xf), REG_DATA_LOW | 0x5, REG_DATA_HIGH_WRITE | 0x5, - REG_READ_ADDR, /* Read scratch register. */ + REG_READ_ADDR, + /* Write 0xaa to scratch register, read back. */ REG_DATA_LOW | 0xa, REG_DATA_HIGH_WRITE | 0xa, - REG_READ_ADDR, /* Read scratch register. */ + REG_READ_ADDR, + /* Initiate SDRAM initialization in mode register. */ REG_ADDR_LOW | (WRITE_MODE & 0xf), - REG_DATA_LOW | 0x0, - REG_DATA_HIGH_WRITE | 0x8, + REG_DATA_LOW | (mode_regval & 0xf), + REG_DATA_HIGH_WRITE | (mode_regval >> 4), }; - uint8_t result[3]; int ret; - /* Initialize the logic analyzer mode. */ + /* + * Send the command sequence which contains 3 READ requests. + * Expect to see the corresponding 3 response bytes. + */ sigma_write(logic_mode_start, sizeof(logic_mode_start), devc); - - /* Expect a 3 byte reply since we issued three READ requests. */ - ret = sigma_read(result, 3, devc); - if (ret != 3) + ret = sigma_read(result, ARRAY_SIZE(result), devc); + if (ret != ARRAY_SIZE(result)) goto err; - if (result[0] != 0xa6 || result[1] != 0x55 || result[2] != 0xaa) goto err; return SR_OK; + err: sr_err("Configuration failed. Invalid reply received."); return SR_ERR; @@ -375,24 +428,27 @@ err: static int sigma_fw_2_bitbang(struct sr_context *ctx, const char *name, uint8_t **bb_cmd, gsize *bb_cmd_size) { - size_t i, file_size, bb_size; - char *firmware; - uint8_t *bb_stream, *bbs; + uint8_t *firmware; + size_t file_size; + uint8_t *p; + size_t l; uint32_t imm; - int bit, v; - int ret = SR_OK; + size_t bb_size; + uint8_t *bb_stream, *bbs, byte, mask, v; /* Retrieve the on-disk firmware file content. */ - firmware = sr_resource_load(ctx, SR_RESOURCE_FIRMWARE, - name, &file_size, 256 * 1024); + firmware = sr_resource_load(ctx, SR_RESOURCE_FIRMWARE, name, + &file_size, SIGMA_FIRMWARE_SIZE_LIMIT); if (!firmware) - return SR_ERR; + return SR_ERR_IO; /* Unscramble the file content (XOR with "random" sequence). */ + p = firmware; + l = file_size; imm = 0x3f6df2ab; - for (i = 0; i < file_size; i++) { + while (l--) { imm = (imm + 0xa853753) % 177 + (imm * 0x8034052); - firmware[i] ^= imm & 0xff; + *p++ ^= imm & 0xff; } /* @@ -411,28 +467,32 @@ static int sigma_fw_2_bitbang(struct sr_context *ctx, const char *name, * the bitbang samples, and release the allocated memory. */ bb_size = file_size * 8 * 2; - bb_stream = (uint8_t *)g_try_malloc(bb_size); + bb_stream = g_try_malloc(bb_size); if (!bb_stream) { sr_err("%s: Failed to allocate bitbang stream", __func__); - ret = SR_ERR_MALLOC; - goto exit; + g_free(firmware); + return SR_ERR_MALLOC; } bbs = bb_stream; - for (i = 0; i < file_size; i++) { - for (bit = 7; bit >= 0; bit--) { - v = (firmware[i] & (1 << bit)) ? 0x40 : 0x00; - *bbs++ = v | 0x01; + p = firmware; + l = file_size; + while (l--) { + byte = *p++; + mask = 0x80; + while (mask) { + v = (byte & mask) ? BB_PIN_DIN : 0; + mask >>= 1; + *bbs++ = v | BB_PIN_CCLK; *bbs++ = v; } } + g_free(firmware); /* The transformation completed successfully, return the result. */ *bb_cmd = bb_stream; *bb_cmd_size = bb_size; -exit: - g_free(firmware); - return ret; + return SR_OK; } static int upload_firmware(struct sr_context *ctx, @@ -442,39 +502,35 @@ static int upload_firmware(struct sr_context *ctx, unsigned char *buf; unsigned char pins; size_t buf_size; - const char *firmware = sigma_firmware_files[firmware_idx]; - struct ftdi_context *ftdic = &devc->ftdic; + const char *firmware; - /* Make sure it's an ASIX SIGMA. */ - ret = ftdi_usb_open_desc(ftdic, USB_VENDOR, USB_PRODUCT, - USB_DESCRIPTION, NULL); - if (ret < 0) { - sr_err("ftdi_usb_open failed: %s", - ftdi_get_error_string(ftdic)); - return 0; + /* Avoid downloading the same firmware multiple times. */ + firmware = firmware_files[firmware_idx]; + if (devc->cur_firmware == firmware_idx) { + sr_info("Not uploading firmware file '%s' again.", firmware); + return SR_OK; } - ret = ftdi_set_bitmode(ftdic, 0xdf, BITMODE_BITBANG); + /* Set the cable to bitbang mode. */ + ret = ftdi_set_bitmode(&devc->ftdic, BB_PINMASK, BITMODE_BITBANG); if (ret < 0) { sr_err("ftdi_set_bitmode failed: %s", - ftdi_get_error_string(ftdic)); - return 0; + ftdi_get_error_string(&devc->ftdic)); + return SR_ERR; } - - /* Four times the speed of sigmalogan - Works well. */ - ret = ftdi_set_baudrate(ftdic, 750 * 1000); + ret = ftdi_set_baudrate(&devc->ftdic, BB_BITRATE); if (ret < 0) { sr_err("ftdi_set_baudrate failed: %s", - ftdi_get_error_string(ftdic)); - return 0; + ftdi_get_error_string(&devc->ftdic)); + return SR_ERR; } - /* Initialize the FPGA for firmware upload. */ + /* Initiate FPGA configuration mode. */ ret = sigma_fpga_init_bitbang(devc); if (ret) return ret; - /* Prepare firmware. */ + /* Prepare wire format of the firmware image. */ ret = sigma_fw_2_bitbang(ctx, firmware, &buf, &buf_size); if (ret != SR_OK) { sr_err("An error occurred while reading the firmware: %s", @@ -482,22 +538,20 @@ static int upload_firmware(struct sr_context *ctx, return ret; } - /* Upload firmware. */ + /* Write the FPGA netlist to the cable. */ sr_info("Uploading firmware file '%s'.", firmware); sigma_write(buf, buf_size, devc); g_free(buf); - ret = ftdi_set_bitmode(ftdic, 0x00, BITMODE_RESET); + /* Leave bitbang mode and discard pending input data. */ + ret = ftdi_set_bitmode(&devc->ftdic, 0, BITMODE_RESET); if (ret < 0) { sr_err("ftdi_set_bitmode failed: %s", - ftdi_get_error_string(ftdic)); + ftdi_get_error_string(&devc->ftdic)); return SR_ERR; } - - ftdi_usb_purge_buffers(ftdic); - - /* Discard garbage. */ + ftdi_usb_purge_buffers(&devc->ftdic); while (sigma_read(&pins, 1, devc) == 1) ; @@ -506,97 +560,329 @@ static int upload_firmware(struct sr_context *ctx, if (ret != SR_OK) return ret; + /* Keep track of successful firmware download completion. */ devc->cur_firmware = firmware_idx; - sr_info("Firmware uploaded."); return SR_OK; } /* - * Sigma doesn't support limiting the number of samples, so we have to - * translate the number and the samplerate to an elapsed time. + * The driver supports user specified time or sample count limits. The + * device's hardware supports neither, and hardware compression prevents + * reliable detection of "fill levels" (currently reached sample counts) + * from register values during acquisition. That's why the driver needs + * to apply some heuristics: + * + * - The (optional) sample count limit and the (normalized) samplerate + * get mapped to an estimated duration for these samples' acquisition. + * - The (optional) time limit gets checked as well. The lesser of the + * two limits will terminate the data acquisition phase. The exact + * sample count limit gets enforced in session feed submission paths. + * - Some slack needs to be given to account for hardware pipelines as + * well as late storage of last chunks after compression thresholds + * are tripped. The resulting data set will span at least the caller + * specified period of time, which shall be perfectly acceptable. * - * In addition we need to ensure that the last data cluster has passed - * the hardware pipeline, and became available to the PC side. With RLE - * compression up to 327ms could pass before another cluster accumulates - * at 200kHz samplerate when input pins don't change. + * With RLE compression active, up to 64K sample periods can pass before + * a cluster accumulates. Which translates to 327ms at 200kHz. Add two + * times that period for good measure, one is not enough to flush the + * hardware pipeline (observation from an earlier experiment). */ -SR_PRIV uint64_t sigma_limit_samples_to_msec(const struct dev_context *devc, - uint64_t limit_samples) +SR_PRIV int sigma_set_acquire_timeout(struct dev_context *devc) { - uint64_t limit_msec; + int ret; + GVariant *data; + uint64_t user_count, user_msecs; uint64_t worst_cluster_time_ms; + uint64_t count_msecs, acquire_msecs; - limit_msec = limit_samples * 1000 / devc->cur_samplerate; - worst_cluster_time_ms = 65536 * 1000 / devc->cur_samplerate; - /* - * One cluster time is not enough to flush pipeline when sampling - * grounded pins with 1 sample limit at 200kHz. Hence the 2* fix. - */ - return limit_msec + 2 * worst_cluster_time_ms; + sr_sw_limits_init(&devc->acq_limits); + + /* Get sample count limit, convert to msecs. */ + ret = sr_sw_limits_config_get(&devc->cfg_limits, + SR_CONF_LIMIT_SAMPLES, &data); + if (ret != SR_OK) + return ret; + user_count = g_variant_get_uint64(data); + g_variant_unref(data); + count_msecs = 0; + if (user_count) + count_msecs = 1000 * user_count / devc->samplerate + 1; + + /* Get time limit, which is in msecs. */ + ret = sr_sw_limits_config_get(&devc->cfg_limits, + SR_CONF_LIMIT_MSEC, &data); + if (ret != SR_OK) + return ret; + user_msecs = g_variant_get_uint64(data); + g_variant_unref(data); + + /* Get the lesser of them, with both being optional. */ + acquire_msecs = ~0ull; + if (user_count && count_msecs < acquire_msecs) + acquire_msecs = count_msecs; + if (user_msecs && user_msecs < acquire_msecs) + acquire_msecs = user_msecs; + if (acquire_msecs == ~0ull) + return SR_OK; + + /* Add some slack, and use that timeout for acquisition. */ + worst_cluster_time_ms = 1000 * 65536 / devc->samplerate; + acquire_msecs += 2 * worst_cluster_time_ms; + data = g_variant_new_uint64(acquire_msecs); + ret = sr_sw_limits_config_set(&devc->acq_limits, + SR_CONF_LIMIT_MSEC, data); + g_variant_unref(data); + if (ret != SR_OK) + return ret; + + sr_sw_limits_acquisition_start(&devc->acq_limits); + return SR_OK; } -SR_PRIV int sigma_set_samplerate(const struct sr_dev_inst *sdi, uint64_t samplerate) +/* + * Check whether a caller specified samplerate matches the device's + * hardware constraints (can be used for acquisition). Optionally yield + * a value that approximates the original spec. + * + * This routine assumes that input specs are in the 200kHz to 200MHz + * range of supported rates, and callers typically want to normalize a + * given value to the hardware capabilities. Values in the 50MHz range + * get rounded up by default, to avoid a more expensive check for the + * closest match, while higher sampling rate is always desirable during + * measurement. Input specs which exactly match hardware capabilities + * remain unaffected. Because 100/200MHz rates also limit the number of + * available channels, they are not suggested by this routine, instead + * callers need to pick them consciously. + */ +SR_PRIV int sigma_normalize_samplerate(uint64_t want_rate, uint64_t *have_rate) +{ + uint64_t div, rate; + + /* Accept exact matches for 100/200MHz. */ + if (want_rate == SR_MHZ(200) || want_rate == SR_MHZ(100)) { + if (have_rate) + *have_rate = want_rate; + return SR_OK; + } + + /* Accept 200kHz to 50MHz range, and map to near value. */ + if (want_rate >= SR_KHZ(200) && want_rate <= SR_MHZ(50)) { + div = SR_MHZ(50) / want_rate; + rate = SR_MHZ(50) / div; + if (have_rate) + *have_rate = rate; + return SR_OK; + } + + return SR_ERR_ARG; +} + +SR_PRIV int sigma_set_samplerate(const struct sr_dev_inst *sdi) { struct dev_context *devc; struct drv_context *drvc; - size_t i; + uint64_t samplerate; int ret; + int num_channels; devc = sdi->priv; drvc = sdi->driver->context; - ret = SR_OK; - /* Reject rates that are not in the list of supported rates. */ - for (i = 0; i < samplerates_count; i++) { - if (samplerates[i] == samplerate) - break; - } - if (i >= samplerates_count || samplerates[i] == 0) - return SR_ERR_SAMPLERATE; + /* Accept any caller specified rate which the hardware supports. */ + ret = sigma_normalize_samplerate(devc->samplerate, &samplerate); + if (ret != SR_OK) + return ret; /* * Depending on the samplerates of 200/100/50- MHz, specific * firmware is required and higher rates might limit the set * of available channels. */ + num_channels = devc->num_channels; if (samplerate <= SR_MHZ(50)) { ret = upload_firmware(drvc->sr_ctx, 0, devc); - devc->num_channels = 16; + num_channels = 16; } else if (samplerate == SR_MHZ(100)) { ret = upload_firmware(drvc->sr_ctx, 1, devc); - devc->num_channels = 8; + num_channels = 8; } else if (samplerate == SR_MHZ(200)) { ret = upload_firmware(drvc->sr_ctx, 2, devc); - devc->num_channels = 4; + num_channels = 4; } /* - * Derive the sample period from the sample rate as well as the - * number of samples that the device will communicate within - * an "event" (memory organization internal to the device). + * The samplerate affects the number of available logic channels + * as well as a sample memory layout detail (the number of samples + * which the device will communicate within an "event"). */ if (ret == SR_OK) { - devc->cur_samplerate = samplerate; - devc->period_ps = 1000000000000ULL / samplerate; + devc->num_channels = num_channels; devc->samples_per_event = 16 / devc->num_channels; devc->state.state = SIGMA_IDLE; } + return ret; +} + +/* + * Arrange for a session feed submit buffer. A queue where a number of + * samples gets accumulated to reduce the number of send calls. Which + * also enforces an optional sample count limit for data acquisition. + * + * The buffer holds up to CHUNK_SIZE bytes. The unit size is fixed (the + * driver provides a fixed channel layout regardless of samplerate). + */ + +#define CHUNK_SIZE (4 * 1024 * 1024) + +struct submit_buffer { + size_t unit_size; + size_t max_samples, curr_samples; + uint8_t *sample_data; + uint8_t *write_pointer; + struct sr_dev_inst *sdi; + struct sr_datafeed_packet packet; + struct sr_datafeed_logic logic; +}; + +static int alloc_submit_buffer(struct sr_dev_inst *sdi) +{ + struct dev_context *devc; + struct submit_buffer *buffer; + size_t size; + + devc = sdi->priv; + + buffer = g_malloc0(sizeof(*buffer)); + devc->buffer = buffer; + + buffer->unit_size = sizeof(uint16_t); + size = CHUNK_SIZE; + size /= buffer->unit_size; + buffer->max_samples = size; + size *= buffer->unit_size; + buffer->sample_data = g_try_malloc0(size); + if (!buffer->sample_data) + return SR_ERR_MALLOC; + buffer->write_pointer = buffer->sample_data; + sr_sw_limits_init(&devc->feed_limits); + + buffer->sdi = sdi; + memset(&buffer->logic, 0, sizeof(buffer->logic)); + buffer->logic.unitsize = buffer->unit_size; + buffer->logic.data = buffer->sample_data; + memset(&buffer->packet, 0, sizeof(buffer->packet)); + buffer->packet.type = SR_DF_LOGIC; + buffer->packet.payload = &buffer->logic; + + return SR_OK; +} + +static int setup_submit_limit(struct dev_context *devc) +{ + struct sr_sw_limits *limits; + int ret; + GVariant *data; + uint64_t total; + + limits = &devc->feed_limits; + + ret = sr_sw_limits_config_get(&devc->cfg_limits, + SR_CONF_LIMIT_SAMPLES, &data); + if (ret != SR_OK) + return ret; + total = g_variant_get_uint64(data); + g_variant_unref(data); + + sr_sw_limits_init(limits); + if (total) { + data = g_variant_new_uint64(total); + ret = sr_sw_limits_config_set(limits, + SR_CONF_LIMIT_SAMPLES, data); + g_variant_unref(data); + if (ret != SR_OK) + return ret; + } + + sr_sw_limits_acquisition_start(limits); + + return SR_OK; +} + +static void free_submit_buffer(struct dev_context *devc) +{ + struct submit_buffer *buffer; + + if (!devc) + return; + + buffer = devc->buffer; + if (!buffer) + return; + devc->buffer = NULL; + + g_free(buffer->sample_data); + g_free(buffer); +} + +static int flush_submit_buffer(struct dev_context *devc) +{ + struct submit_buffer *buffer; + int ret; + + buffer = devc->buffer; + + /* Is queued sample data available? */ + if (!buffer->curr_samples) + return SR_OK; + + /* Submit to the session feed. */ + buffer->logic.length = buffer->curr_samples * buffer->unit_size; + ret = sr_session_send(buffer->sdi, &buffer->packet); + if (ret != SR_OK) + return ret; + + /* Rewind queue position. */ + buffer->curr_samples = 0; + buffer->write_pointer = buffer->sample_data; + + return SR_OK; +} + +static int addto_submit_buffer(struct dev_context *devc, + uint16_t sample, size_t count) +{ + struct submit_buffer *buffer; + struct sr_sw_limits *limits; + int ret; + + buffer = devc->buffer; + limits = &devc->feed_limits; + if (sr_sw_limits_check(limits)) + count = 0; + /* - * Support for "limit_samples" is implemented by stopping - * acquisition after a corresponding period of time. - * Re-calculate that period of time, in case the limit is - * set first and the samplerate gets (re-)configured later. + * Individually accumulate and check each sample, such that + * accumulation between flushes won't exceed local storage, and + * enforcement of user specified limits is exact. */ - if (ret == SR_OK && devc->limit_samples) { - uint64_t msecs; - msecs = sigma_limit_samples_to_msec(devc, devc->limit_samples); - devc->limit_msec = msecs; + while (count--) { + WL16(buffer->write_pointer, sample); + buffer->write_pointer += buffer->unit_size; + buffer->curr_samples++; + if (buffer->curr_samples == buffer->max_samples) { + ret = flush_submit_buffer(devc); + if (ret != SR_OK) + return ret; + } + sr_sw_limits_update_samples_read(limits, 1); + if (sr_sw_limits_check(limits)) + break; } - return ret; + return SR_OK; } /* @@ -630,7 +916,7 @@ SR_PRIV int sigma_convert_trigger(const struct sr_dev_inst *sdi) /* Ignore disabled channels with a trigger. */ continue; channelbit = 1 << (match->channel->index); - if (devc->cur_samplerate >= SR_MHZ(100)) { + if (devc->samplerate >= SR_MHZ(100)) { /* Fast trigger support. */ if (trigger_set) { sr_err("Only a single pin trigger is " @@ -653,16 +939,13 @@ SR_PRIV int sigma_convert_trigger(const struct sr_dev_inst *sdi) if (match->match == SR_TRIGGER_ONE) { devc->trigger.simplevalue |= channelbit; devc->trigger.simplemask |= channelbit; - } - else if (match->match == SR_TRIGGER_ZERO) { + } else if (match->match == SR_TRIGGER_ZERO) { devc->trigger.simplevalue &= ~channelbit; devc->trigger.simplemask |= channelbit; - } - else if (match->match == SR_TRIGGER_FALLING) { + } else if (match->match == SR_TRIGGER_FALLING) { devc->trigger.fallingmask |= channelbit; trigger_set++; - } - else if (match->match == SR_TRIGGER_RISING) { + } else if (match->match == SR_TRIGGER_RISING) { devc->trigger.risingmask |= channelbit; trigger_set++; } @@ -684,7 +967,6 @@ SR_PRIV int sigma_convert_trigger(const struct sr_dev_inst *sdi) return SR_OK; } - /* Software trigger to determine exact trigger position. */ static int get_trigger_offset(uint8_t *samples, uint16_t last_sample, struct sigma_trigger *t) @@ -718,6 +1000,48 @@ static int get_trigger_offset(uint8_t *samples, uint16_t last_sample, return i & 0x7; } +static gboolean sample_matches_trigger(struct dev_context *devc, uint16_t sample) +{ + /* TODO + * Check whether the combination of this very sample and the + * previous state match the configured trigger condition. This + * improves the resolution of the trigger marker's position. + * The hardware provided position is coarse, and may point to + * a position before the actual match. + * + * See the previous get_trigger_offset() implementation. This + * code needs to get re-used here. + */ + (void)devc; + (void)sample; + (void)get_trigger_offset; + + return FALSE; +} + +static int check_and_submit_sample(struct dev_context *devc, + uint16_t sample, size_t count, gboolean check_trigger) +{ + gboolean triggered; + int ret; + + triggered = check_trigger && sample_matches_trigger(devc, sample); + if (triggered) { + ret = flush_submit_buffer(devc); + if (ret != SR_OK) + return ret; + ret = std_session_send_df_trigger(devc->buffer->sdi); + if (ret != SR_OK) + return ret; + } + + ret = addto_submit_buffer(devc, sample, count); + if (ret != SR_OK) + return ret; + + return SR_OK; +} + /* * Return the timestamp of "DRAM cluster". */ @@ -780,146 +1104,66 @@ static uint16_t sigma_deinterlace_200mhz_data(uint16_t indata, int idx) return outdata; } -static void store_sr_sample(uint8_t *samples, int idx, uint16_t data) +static void sigma_decode_dram_cluster(struct dev_context *devc, + struct sigma_dram_cluster *dram_cluster, + size_t events_in_cluster, gboolean triggered) { - samples[2 * idx + 0] = (data >> 0) & 0xff; - samples[2 * idx + 1] = (data >> 8) & 0xff; -} - -/* - * This size translates to: event count (1K events per cluster), times - * the sample width (unitsize, 16bits per event), times the maximum - * number of samples per event. - */ -#define SAMPLES_BUFFER_SIZE (1024 * 2 * 4) - -static void sigma_decode_dram_cluster(struct sigma_dram_cluster *dram_cluster, - unsigned int events_in_cluster, - unsigned int triggered, - struct sr_dev_inst *sdi) -{ - struct dev_context *devc = sdi->priv; - struct sigma_state *ss = &devc->state; - struct sr_datafeed_packet packet; - struct sr_datafeed_logic logic; + struct sigma_state *ss; uint16_t tsdiff, ts, sample, item16; - uint8_t samples[SAMPLES_BUFFER_SIZE]; - uint8_t *send_ptr; - size_t send_count, trig_count; unsigned int i; - int j; - - ts = sigma_dram_cluster_ts(dram_cluster); - tsdiff = ts - ss->lastts; - ss->lastts = ts + EVENTS_PER_CLUSTER; - packet.type = SR_DF_LOGIC; - packet.payload = &logic; - logic.unitsize = 2; - logic.data = samples; + if (!devc->use_triggers || !ASIX_SIGMA_WITH_TRIGGER) + triggered = FALSE; /* - * First of all, send Sigrok a copy of the last sample from - * previous cluster as many times as needed to make up for - * the differential characteristics of data we get from the - * Sigma. Sigrok needs one sample of data per period. + * If this cluster is not adjacent to the previously received + * cluster, then send the appropriate number of samples with the + * previous values to the sigrok session. This "decodes RLE". * - * One DRAM cluster contains a timestamp and seven samples, - * the units of timestamp are "devc->period_ps" , the first - * sample in the cluster happens at the time of the timestamp - * and the remaining samples happen at timestamp +1...+6 . + * These samples cannot match the trigger since they just repeat + * the previously submitted data pattern. (This assumption holds + * for simple level and edge triggers. It would not for timed or + * counted conditions, which currently are not supported.) */ - for (ts = 0; ts < tsdiff; ts++) { - i = ts % 1024; - store_sr_sample(samples, i, ss->lastsample); - - /* - * If we have 1024 samples ready or we're at the - * end of submitting the padding samples, submit - * the packet to Sigrok. Since constant data is - * sent, duplication of data for rates above 50MHz - * is simple. - */ - if ((i == 1023) || (ts == tsdiff - 1)) { - logic.length = (i + 1) * logic.unitsize; - for (j = 0; j < devc->samples_per_event; j++) - sr_session_send(sdi, &packet); - } + ss = &devc->state; + ts = sigma_dram_cluster_ts(dram_cluster); + tsdiff = ts - ss->lastts; + if (tsdiff > 0) { + size_t count; + count = tsdiff * devc->samples_per_event; + (void)check_and_submit_sample(devc, ss->lastsample, count, FALSE); } + ss->lastts = ts + EVENTS_PER_CLUSTER; /* - * Parse the samples in current cluster and prepare them - * to be submitted to Sigrok. Cope with memory layouts that - * vary with the samplerate. + * Grab sample data from the current cluster and prepare their + * submission to the session feed. Handle samplerate dependent + * memory layout of sample data. Accumulation of data chunks + * before submission is transparent to this code path, specific + * buffer depth is neither assumed nor required here. */ - send_ptr = &samples[0]; - send_count = 0; sample = 0; for (i = 0; i < events_in_cluster; i++) { item16 = sigma_dram_cluster_data(dram_cluster, i); - if (devc->cur_samplerate == SR_MHZ(200)) { + if (devc->samplerate == SR_MHZ(200)) { sample = sigma_deinterlace_200mhz_data(item16, 0); - store_sr_sample(samples, send_count++, sample); + check_and_submit_sample(devc, sample, 1, triggered); sample = sigma_deinterlace_200mhz_data(item16, 1); - store_sr_sample(samples, send_count++, sample); + check_and_submit_sample(devc, sample, 1, triggered); sample = sigma_deinterlace_200mhz_data(item16, 2); - store_sr_sample(samples, send_count++, sample); + check_and_submit_sample(devc, sample, 1, triggered); sample = sigma_deinterlace_200mhz_data(item16, 3); - store_sr_sample(samples, send_count++, sample); - } else if (devc->cur_samplerate == SR_MHZ(100)) { + check_and_submit_sample(devc, sample, 1, triggered); + } else if (devc->samplerate == SR_MHZ(100)) { sample = sigma_deinterlace_100mhz_data(item16, 0); - store_sr_sample(samples, send_count++, sample); + check_and_submit_sample(devc, sample, 1, triggered); sample = sigma_deinterlace_100mhz_data(item16, 1); - store_sr_sample(samples, send_count++, sample); + check_and_submit_sample(devc, sample, 1, triggered); } else { sample = item16; - store_sr_sample(samples, send_count++, sample); + check_and_submit_sample(devc, sample, 1, triggered); } } - - /* - * If a trigger position applies, then provide the datafeed with - * the first part of data up to that position, then send the - * trigger marker. - */ - int trigger_offset = 0; - if (triggered) { - /* - * Trigger is not always accurate to sample because of - * pipeline delay. However, it always triggers before - * the actual event. We therefore look at the next - * samples to pinpoint the exact position of the trigger. - */ - trigger_offset = get_trigger_offset(samples, - ss->lastsample, &devc->trigger); - - if (trigger_offset > 0) { - trig_count = trigger_offset * devc->samples_per_event; - packet.type = SR_DF_LOGIC; - logic.length = trig_count * logic.unitsize; - sr_session_send(sdi, &packet); - send_ptr += trig_count * logic.unitsize; - send_count -= trig_count; - } - - /* Only send trigger if explicitly enabled. */ - if (devc->use_triggers) { - packet.type = SR_DF_TRIGGER; - sr_session_send(sdi, &packet); - } - } - - /* - * Send the data after the trigger, or all of the received data - * if no trigger position applies. - */ - if (send_count) { - packet.type = SR_DF_LOGIC; - logic.length = send_count * logic.unitsize; - logic.data = send_ptr; - sr_session_send(sdi, &packet); - } - ss->lastsample = sample; } @@ -932,22 +1176,24 @@ static void sigma_decode_dram_cluster(struct sigma_dram_cluster *dram_cluster, * For 50 MHz and below, events contain one sample for each channel, * spread 20 ns apart. */ -static int decode_chunk_ts(struct sigma_dram_line *dram_line, - uint16_t events_in_line, - uint32_t trigger_event, - struct sr_dev_inst *sdi) +static int decode_chunk_ts(struct dev_context *devc, + struct sigma_dram_line *dram_line, + size_t events_in_line, size_t trigger_event) { struct sigma_dram_cluster *dram_cluster; - struct dev_context *devc = sdi->priv; - unsigned int clusters_in_line = - (events_in_line + (EVENTS_PER_CLUSTER - 1)) / EVENTS_PER_CLUSTER; + unsigned int clusters_in_line; unsigned int events_in_cluster; unsigned int i; - uint32_t trigger_cluster = ~0, triggered = 0; + uint32_t trigger_cluster; + + clusters_in_line = events_in_line; + clusters_in_line += EVENTS_PER_CLUSTER - 1; + clusters_in_line /= EVENTS_PER_CLUSTER; + trigger_cluster = ~0; /* Check if trigger is in this chunk. */ - if (trigger_event < (64 * 7)) { - if (devc->cur_samplerate <= SR_MHZ(50)) { + if (trigger_event < EVENTS_PER_ROW) { + if (devc->samplerate <= SR_MHZ(50)) { trigger_event -= MIN(EVENTS_PER_CLUSTER - 1, trigger_event); } @@ -968,9 +1214,8 @@ static int decode_chunk_ts(struct sigma_dram_line *dram_line, events_in_cluster = EVENTS_PER_CLUSTER; } - triggered = (i == trigger_cluster); - sigma_decode_dram_cluster(dram_cluster, events_in_cluster, - triggered, sdi); + sigma_decode_dram_cluster(devc, dram_cluster, + events_in_cluster, i == trigger_cluster); } return SR_OK; @@ -978,54 +1223,91 @@ static int decode_chunk_ts(struct sigma_dram_line *dram_line, static int download_capture(struct sr_dev_inst *sdi) { - struct dev_context *devc = sdi->priv; const uint32_t chunks_per_read = 32; + + struct dev_context *devc; struct sigma_dram_line *dram_line; int bufsz; uint32_t stoppos, triggerpos; uint8_t modestatus; - uint32_t i; uint32_t dl_lines_total, dl_lines_curr, dl_lines_done; - uint32_t dl_events_in_line = 64 * 7; - uint32_t trg_line = ~0, trg_event = ~0; + uint32_t dl_first_line, dl_line; + uint32_t dl_events_in_line; + uint32_t trg_line, trg_event; + int ret; - dram_line = g_try_malloc0(chunks_per_read * sizeof(*dram_line)); - if (!dram_line) - return FALSE; + devc = sdi->priv; + dl_events_in_line = EVENTS_PER_ROW; sr_info("Downloading sample data."); + devc->state.state = SIGMA_DOWNLOAD; - /* Stop acquisition. */ - sigma_set_register(WRITE_MODE, 0x11, devc); + /* + * Ask the hardware to stop data acquisition. Reception of the + * FORCESTOP request makes the hardware "disable RLE" (store + * clusters to DRAM regardless of whether pin state changes) and + * raise the POSTTRIGGERED flag. + */ + sigma_set_register(WRITE_MODE, WMR_FORCESTOP | WMR_SDRAMWRITEEN, devc); + do { + if (sigma_read_register(READ_MODE, &modestatus, 1, devc) != 1) { + sr_err("failed while waiting for RMR_POSTTRIGGERED bit"); + return FALSE; + } + } while (!(modestatus & RMR_POSTTRIGGERED)); /* Set SDRAM Read Enable. */ - sigma_set_register(WRITE_MODE, 0x02, devc); + sigma_set_register(WRITE_MODE, WMR_SDRAMREADEN, devc); /* Get the current position. */ sigma_read_pos(&stoppos, &triggerpos, devc); /* Check if trigger has fired. */ - modestatus = sigma_get_register(READ_MODE, devc); - if (modestatus & 0x20) { + if (sigma_read_register(READ_MODE, &modestatus, 1, devc) != 1) { + sr_err("failed to read READ_MODE register"); + return FALSE; + } + trg_line = ~0; + trg_event = ~0; + if (modestatus & RMR_TRIGGERED) { trg_line = triggerpos >> 9; trg_event = triggerpos & 0x1ff; } /* - * Determine how many 1024b "DRAM lines" do we need to read from the - * Sigma so we have a complete set of samples. Note that the last - * line can be only partial, containing less than 64 clusters. + * Determine how many "DRAM lines" of 1024 bytes each we need to + * retrieve from the Sigma hardware, so that we have a complete + * set of samples. Note that the last line need not contain 64 + * clusters, it might be partially filled only. + * + * When RMR_ROUND is set, the circular buffer in DRAM has wrapped + * around. Since the status of the very next line is uncertain in + * that case, we skip it and start reading from the next line. */ - dl_lines_total = (stoppos >> 9) + 1; - + dl_first_line = 0; + dl_lines_total = (stoppos >> ROW_SHIFT) + 1; + if (modestatus & RMR_ROUND) { + dl_first_line = dl_lines_total + 1; + dl_lines_total = ROW_COUNT - 2; + } + dram_line = g_try_malloc0(chunks_per_read * sizeof(*dram_line)); + if (!dram_line) + return FALSE; + ret = alloc_submit_buffer(sdi); + if (ret != SR_OK) + return FALSE; + ret = setup_submit_limit(devc); + if (ret != SR_OK) + return FALSE; dl_lines_done = 0; - while (dl_lines_total > dl_lines_done) { /* We can download only up-to 32 DRAM lines in one go! */ - dl_lines_curr = MIN(chunks_per_read, dl_lines_total); + dl_lines_curr = MIN(chunks_per_read, dl_lines_total - dl_lines_done); - bufsz = sigma_read_dram(dl_lines_done, dl_lines_curr, + dl_line = dl_first_line + dl_lines_done; + dl_line %= ROW_COUNT; + bufsz = sigma_read_dram(dl_line, dl_lines_curr, (uint8_t *)dram_line, devc); /* TODO: Check bufsz. For now, just avoid compiler warnings. */ (void)bufsz; @@ -1047,49 +1329,35 @@ static int download_capture(struct sr_dev_inst *sdi) if (dl_lines_done + i == trg_line) trigger_event = trg_event; - decode_chunk_ts(dram_line + i, dl_events_in_line, - trigger_event, sdi); + decode_chunk_ts(devc, dram_line + i, + dl_events_in_line, trigger_event); } dl_lines_done += dl_lines_curr; } + flush_submit_buffer(devc); + free_submit_buffer(devc); + g_free(dram_line); std_session_send_df_end(sdi); - sdi->driver->dev_acquisition_stop(sdi); - - g_free(dram_line); + devc->state.state = SIGMA_IDLE; + sr_dev_acquisition_stop(sdi); return TRUE; } /* - * Handle the Sigma when in CAPTURE mode. This function checks: - * - Sampling time ended - * - DRAM capacity overflow - * This function triggers download of the samples from Sigma - * in case either of the above conditions is true. + * Periodically check the Sigma status when in CAPTURE mode. This routine + * checks whether the configured sample count or sample time have passed, + * and will stop acquisition and download the acquired samples. */ static int sigma_capture_mode(struct sr_dev_inst *sdi) { - struct dev_context *devc = sdi->priv; - - uint64_t running_msec; - struct timeval tv; - - uint32_t stoppos, triggerpos; - - /* Check if the selected sampling duration passed. */ - gettimeofday(&tv, 0); - running_msec = (tv.tv_sec - devc->start_tv.tv_sec) * 1000 + - (tv.tv_usec - devc->start_tv.tv_usec) / 1000; - if (running_msec >= devc->limit_msec) - return download_capture(sdi); + struct dev_context *devc; - /* Get the position in DRAM to which the FPGA is writing now. */ - sigma_read_pos(&stoppos, &triggerpos, devc); - /* Test if DRAM is full and if so, download the data. */ - if ((stoppos >> 9) == 32767) + devc = sdi->priv; + if (sr_sw_limits_check(&devc->acq_limits)) return download_capture(sdi); return TRUE; @@ -1109,6 +1377,14 @@ SR_PRIV int sigma_receive_data(int fd, int revents, void *cb_data) if (devc->state.state == SIGMA_IDLE) return TRUE; + /* + * When the application has requested to stop the acquisition, + * then immediately start downloading sample data. Otherwise + * keep checking configured limits which will terminate the + * acquisition and initiate download. + */ + if (devc->state.state == SIGMA_STOPPING) + return download_capture(sdi); if (devc->state.state == SIGMA_CAPTURE) return sigma_capture_mode(sdi);