]> sigrok.org Git - libsigrok.git/blobdiff - src/hardware/asix-sigma/protocol.c
asix-sigma: improve robustness of parameter upload to hardware
[libsigrok.git] / src / hardware / asix-sigma / protocol.c
index 9a45a2d95c4ae8355f99b410edb198ec35d10766..1875b75658d8358f4a41938f5e0a6c9d64d23476 100644 (file)
@@ -70,11 +70,11 @@ static int sigma_read(struct dev_context *devc, void *buf, size_t size)
        return ret;
 }
 
-static int sigma_write(struct dev_context *devc, void *buf, size_t size)
+static int sigma_write(struct dev_context *devc, const void *buf, size_t size)
 {
        int ret;
 
-       ret = ftdi_write_data(&devc->ftdic, (unsigned char *)buf, size);
+       ret = ftdi_write_data(&devc->ftdic, buf, size);
        if (ret < 0)
                sr_err("ftdi_write_data failed: %s",
                        ftdi_get_error_string(&devc->ftdic));
@@ -91,24 +91,28 @@ static int sigma_write(struct dev_context *devc, void *buf, size_t size)
 SR_PRIV int sigma_write_register(struct dev_context *devc,
        uint8_t reg, uint8_t *data, size_t len)
 {
-       size_t i;
-       uint8_t buf[80];
-       int idx = 0;
+       uint8_t buf[80], *wrptr;
+       size_t idx, count;
+       int ret;
 
-       if ((2 * len + 2) > sizeof(buf)) {
+       if (2 + 2 * len > sizeof(buf)) {
                sr_err("Write buffer too small to write %zu bytes.", len);
                return SR_ERR_BUG;
        }
 
-       buf[idx++] = REG_ADDR_LOW | (reg & 0xf);
-       buf[idx++] = REG_ADDR_HIGH | (reg >> 4);
-
-       for (i = 0; i < len; i++) {
-               buf[idx++] = REG_DATA_LOW | (data[i] & 0xf);
-               buf[idx++] = REG_DATA_HIGH_WRITE | (data[i] >> 4);
+       wrptr = buf;
+       write_u8_inc(&wrptr, REG_ADDR_LOW | (reg & 0xf));
+       write_u8_inc(&wrptr, REG_ADDR_HIGH | (reg >> 4));
+       for (idx = 0; idx < len; idx++) {
+               write_u8_inc(&wrptr, REG_DATA_LOW | (data[idx] & 0xf));
+               write_u8_inc(&wrptr, REG_DATA_HIGH_WRITE | (data[idx] >> 4));
        }
+       count = wrptr - buf;
+       ret = sigma_write(devc, buf, count);
+       if (ret != SR_OK)
+               return ret;
 
-       return sigma_write(devc, buf, idx);
+       return SR_OK;
 }
 
 SR_PRIV int sigma_set_register(struct dev_context *devc,
@@ -120,13 +124,13 @@ SR_PRIV int sigma_set_register(struct dev_context *devc,
 static int sigma_read_register(struct dev_context *devc,
        uint8_t reg, uint8_t *data, size_t len)
 {
-       uint8_t buf[3];
-
-       buf[0] = REG_ADDR_LOW | (reg & 0xf);
-       buf[1] = REG_ADDR_HIGH | (reg >> 4);
-       buf[2] = REG_READ_ADDR;
+       uint8_t buf[3], *wrptr;
 
-       sigma_write(devc, buf, sizeof(buf));
+       wrptr = buf;
+       write_u8_inc(&wrptr, REG_ADDR_LOW | (reg & 0xf));
+       write_u8_inc(&wrptr, REG_ADDR_HIGH | (reg >> 4));
+       write_u8_inc(&wrptr, REG_READ_ADDR);
+       sigma_write(devc, buf, wrptr - buf);
 
        return sigma_read(devc, data, len);
 }
@@ -138,7 +142,7 @@ static int sigma_read_pos(struct dev_context *devc,
         * Read 6 registers starting at trigger position LSB.
         * Which yields two 24bit counter values.
         */
-       uint8_t buf[] = {
+       const uint8_t buf[] = {
                REG_ADDR_LOW | READ_TRIGGER_POS_LOW,
                REG_READ_ADDR | REG_ADDR_INC,
                REG_READ_ADDR | REG_ADDR_INC,
@@ -146,73 +150,73 @@ static int sigma_read_pos(struct dev_context *devc,
                REG_READ_ADDR | REG_ADDR_INC,
                REG_READ_ADDR | REG_ADDR_INC,
                REG_READ_ADDR | REG_ADDR_INC,
-       };
+       }, *rdptr;
        uint8_t result[6];
 
        sigma_write(devc, buf, sizeof(buf));
 
        sigma_read(devc, result, sizeof(result));
 
-       *triggerpos = result[0] | (result[1] << 8) | (result[2] << 16);
-       *stoppos = result[3] | (result[4] << 8) | (result[5] << 16);
+       rdptr = &result[0];
+       *triggerpos = read_u24le_inc(&rdptr);
+       *stoppos = read_u24le_inc(&rdptr);
 
        /*
-        * 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.
+        * These positions consist of "the memory row" in the MSB fields,
+        * and "an event index" within the row in the LSB fields. Part
+        * of the memory row's content is sample data, another part is
+        * timestamps.
         *
-        * 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?
+        * The retrieved register values point to after the captured
+        * position. So they need to get decremented, and adjusted to
+        * cater for the timestamps when the decrement carries over to
+        * a different memory row.
         */
-       if ((--*stoppos & 0x1ff) == 0x1ff)
-               *stoppos -= 64;
-       if ((--*triggerpos & 0x1ff) == 0x1ff)
-               *triggerpos -= 64;
+       if ((--*stoppos & ROW_MASK) == ROW_MASK)
+               *stoppos -= CLUSTERS_PER_ROW;
+       if ((--*triggerpos & ROW_MASK) == ROW_MASK)
+               *triggerpos -= CLUSTERS_PER_ROW;
 
-       return 1;
+       return SR_OK;
 }
 
 static int sigma_read_dram(struct dev_context *devc,
        uint16_t startchunk, size_t numchunks, uint8_t *data)
 {
-       uint8_t buf[4096];
-       int idx;
+       uint8_t buf[128], *wrptr;
        size_t chunk;
        int sel;
        gboolean is_last;
 
+       if (2 + 3 * numchunks > ARRAY_SIZE(buf)) {
+               sr_err("Read buffer too small to read %zu DRAM rows", numchunks);
+               return SR_ERR_BUG;
+       }
+
        /* Communicate DRAM start address (memory row, aka samples line). */
-       idx = 0;
-       buf[idx++] = startchunk >> 8;
-       buf[idx++] = startchunk & 0xff;
-       sigma_write_register(devc, WRITE_MEMROW, buf, idx);
+       wrptr = buf;
+       write_u8_inc(&wrptr, startchunk >> 8);
+       write_u8_inc(&wrptr, startchunk & 0xff);
+       sigma_write_register(devc, WRITE_MEMROW, buf, wrptr - buf);
 
        /*
         * 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;
+       wrptr = buf;
+       write_u8_inc(&wrptr, REG_DRAM_BLOCK);
+       write_u8_inc(&wrptr, REG_DRAM_WAIT_ACK);
        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);
+                       write_u8_inc(&wrptr, REG_DRAM_BLOCK | REG_DRAM_SEL_BOOL(!sel));
+               write_u8_inc(&wrptr, REG_DRAM_BLOCK_DATA | REG_DRAM_SEL_BOOL(sel));
                if (!is_last)
-                       buf[idx++] = REG_DRAM_WAIT_ACK;
+                       write_u8_inc(&wrptr, REG_DRAM_WAIT_ACK);
        }
-       sigma_write(devc, buf, idx);
+       sigma_write(devc, buf, wrptr - buf);
 
        return sigma_read(devc, data, numchunks * ROW_LENGTH_BYTES);
 }
@@ -224,6 +228,7 @@ SR_PRIV int sigma_write_trigger_lut(struct dev_context *devc,
        int i;
        uint8_t tmp[2];
        uint16_t bit;
+       uint8_t buf[6], *wrptr, regval;
 
        /* Transpose the table and send to Sigma. */
        for (i = 0; i < 16; i++) {
@@ -265,14 +270,33 @@ SR_PRIV int sigma_write_trigger_lut(struct dev_context *devc,
                if (lut->m1d[3] & bit)
                        tmp[1] |= 0x80;
 
-               sigma_write_register(devc, WRITE_TRIGGER_SELECT,
-                       tmp, sizeof(tmp));
+               /*
+                * This logic seems redundant, but separates the value
+                * determination from the wire format, and is useful
+                * during future maintenance and research.
+                */
+               wrptr = buf;
+               write_u8_inc(&wrptr, tmp[0]);
+               write_u8_inc(&wrptr, tmp[1]);
+               sigma_write_register(devc, WRITE_TRIGGER_SELECT, buf, wrptr - buf);
                sigma_set_register(devc, WRITE_TRIGGER_SELECT2, 0x30 | i);
        }
 
        /* Send the parameters */
-       sigma_write_register(devc, WRITE_TRIGGER_SELECT,
-               (uint8_t *)&lut->params, sizeof(lut->params));
+       wrptr = buf;
+       regval = 0;
+       regval |= lut->params.selc << 6;
+       regval |= lut->params.selpresc << 0;
+       write_u8_inc(&wrptr, regval);
+       regval = 0;
+       regval |= lut->params.selinc << 6;
+       regval |= lut->params.selres << 4;
+       regval |= lut->params.sela << 2;
+       regval |= lut->params.selb << 0;
+       write_u8_inc(&wrptr, regval);
+       write_u16le_inc(&wrptr, lut->params.cmpb);
+       write_u16le_inc(&wrptr, lut->params.cmpa);
+       sigma_write_register(devc, WRITE_TRIGGER_SELECT, buf, wrptr - buf);
 
        return SR_OK;
 }
@@ -325,7 +349,7 @@ SR_PRIV int sigma_write_trigger_lut(struct dev_context *devc,
  */
 static int sigma_fpga_init_bitbang_once(struct dev_context *devc)
 {
-       uint8_t suicide[] = {
+       const uint8_t suicide[] = {
                BB_PIN_D7 | BB_PIN_D2,
                BB_PIN_D7 | BB_PIN_D2,
                BB_PIN_D7 |           BB_PIN_D3,
@@ -335,7 +359,7 @@ static int sigma_fpga_init_bitbang_once(struct dev_context *devc)
                BB_PIN_D7 |           BB_PIN_D3,
                BB_PIN_D7 | BB_PIN_D2,
        };
-       uint8_t init_array[] = {
+       const uint8_t init_array[] = {
                BB_PIN_CCLK,
                BB_PIN_CCLK | BB_PIN_PROG,
                BB_PIN_CCLK | BB_PIN_PROG,
@@ -365,7 +389,7 @@ static int sigma_fpga_init_bitbang_once(struct dev_context *devc)
        /* Wait until the FPGA asserts INIT_B. */
        retries = 10;
        while (retries--) {
-               ret = sigma_read(devc, &data, 1);
+               ret = sigma_read(devc, &data, sizeof(data));
                if (ret < 0)
                        return ret;
                if (data & BB_PIN_INIT)
@@ -402,52 +426,64 @@ static int sigma_fpga_init_bitbang(struct dev_context *devc)
  */
 static int sigma_fpga_init_la(struct dev_context *devc)
 {
-       /*
-        * 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 >> 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,
-
-               /* Write 0xaa to scratch register, read back. */
-               REG_DATA_LOW | 0xa,
-               REG_DATA_HIGH_WRITE | 0xa,
-               REG_READ_ADDR,
-
-               /* Initiate SDRAM initialization in mode register. */
-               REG_ADDR_LOW | (WRITE_MODE & 0xf),
-               REG_DATA_LOW | (mode_regval & 0xf),
-               REG_DATA_HIGH_WRITE | (mode_regval >> 4),
-       };
+       uint8_t buf[16], *wrptr;
+       uint8_t data_55, data_aa, mode;
        uint8_t result[3];
+       const uint8_t *rdptr;
        int ret;
 
+       wrptr = buf;
+
+       /* Read ID register. */
+       write_u8_inc(&wrptr, REG_ADDR_LOW | (READ_ID & 0xf));
+       write_u8_inc(&wrptr, REG_ADDR_HIGH | (READ_ID >> 4));
+       write_u8_inc(&wrptr, REG_READ_ADDR);
+
+       /* Write 0x55 to scratch register, read back. */
+       data_55 = 0x55;
+       write_u8_inc(&wrptr, REG_ADDR_LOW | (WRITE_TEST & 0xf));
+       write_u8_inc(&wrptr, REG_DATA_LOW | (data_55 & 0xf));
+       write_u8_inc(&wrptr, REG_DATA_HIGH_WRITE | (data_55 >> 4));
+       write_u8_inc(&wrptr, REG_READ_ADDR);
+
+       /* Write 0xaa to scratch register, read back. */
+       data_aa = 0xaa;
+       write_u8_inc(&wrptr, REG_ADDR_LOW | (WRITE_TEST & 0xf));
+       write_u8_inc(&wrptr, REG_DATA_LOW | (data_aa & 0xf));
+       write_u8_inc(&wrptr, REG_DATA_HIGH_WRITE | (data_aa >> 4));
+       write_u8_inc(&wrptr, REG_READ_ADDR);
+
+       /* Initiate SDRAM initialization in mode register. */
+       mode = WMR_SDRAMINIT;
+       write_u8_inc(&wrptr, REG_ADDR_LOW | (WRITE_MODE & 0xf));
+       write_u8_inc(&wrptr, REG_DATA_LOW | (mode & 0xf));
+       write_u8_inc(&wrptr, REG_DATA_HIGH_WRITE | (mode >> 4));
+
        /*
         * Send the command sequence which contains 3 READ requests.
         * Expect to see the corresponding 3 response bytes.
         */
-       sigma_write(devc, logic_mode_start, sizeof(logic_mode_start));
+       sigma_write(devc, buf, wrptr - buf);
        ret = sigma_read(devc, result, ARRAY_SIZE(result));
-       if (ret != ARRAY_SIZE(result))
-               goto err;
-       if (result[0] != 0xa6 || result[1] != 0x55 || result[2] != 0xaa)
-               goto err;
+       if (ret != ARRAY_SIZE(result)) {
+               sr_err("Insufficient start response length.");
+               return SR_ERR_IO;
+       }
+       rdptr = result;
+       if (read_u8_inc(&rdptr) != 0xa6) {
+               sr_err("Unexpected ID response.");
+               return SR_ERR_DATA;
+       }
+       if (read_u8_inc(&rdptr) != data_55) {
+               sr_err("Unexpected scratch read-back (55).");
+               return SR_ERR_DATA;
+       }
+       if (read_u8_inc(&rdptr) != data_aa) {
+               sr_err("Unexpected scratch read-back (aa).");
+               return SR_ERR_DATA;
+       }
 
        return SR_OK;
-
-err:
-       sr_err("Configuration failed. Invalid reply received.");
-       return SR_ERR;
 }
 
 /*
@@ -529,8 +565,8 @@ static int upload_firmware(struct sr_context *ctx, struct dev_context *devc,
        enum sigma_firmware_idx firmware_idx)
 {
        int ret;
-       unsigned char *buf;
-       unsigned char pins;
+       uint8_t *buf;
+       uint8_t pins;
        size_t buf_size;
        const char *firmware;
 
@@ -589,7 +625,7 @@ static int upload_firmware(struct sr_context *ctx, struct dev_context *devc,
                return SR_ERR;
        }
        ftdi_usb_purge_buffers(&devc->ftdic);
-       while (sigma_read(devc, &pins, 1) == 1)
+       while (sigma_read(devc, &pins, sizeof(pins)) > 0)
                ;
 
        /* Initialize the FPGA for logic-analyzer mode. */
@@ -906,8 +942,7 @@ static int addto_submit_buffer(struct dev_context *devc,
         * enforcement of user specified limits is exact.
         */
        while (count--) {
-               WL16(buffer->write_pointer, sample);
-               buffer->write_pointer += buffer->unit_size;
+               write_u16le_inc(&buffer->write_pointer, sample);
                buffer->curr_samples++;
                if (buffer->curr_samples == buffer->max_samples) {
                        ret = flush_submit_buffer(devc);
@@ -952,7 +987,7 @@ SR_PRIV int sigma_convert_trigger(const struct sr_dev_inst *sdi)
                        /* Ignore disabled channels with a trigger. */
                        if (!match->channel->enabled)
                                continue;
-                       channelbit = 1 << (match->channel->index);
+                       channelbit = 1 << match->channel->index;
                        if (devc->samplerate >= SR_MHZ(100)) {
                                /* Fast trigger support. */
                                if (trigger_set) {
@@ -960,11 +995,11 @@ SR_PRIV int sigma_convert_trigger(const struct sr_dev_inst *sdi)
                                                "supported in 100 and 200MHz mode.");
                                        return SR_ERR;
                                }
-                               if (match->match == SR_TRIGGER_FALLING)
+                               if (match->match == SR_TRIGGER_FALLING) {
                                        devc->trigger.fallingmask |= channelbit;
-                               else if (match->match == SR_TRIGGER_RISING)
+                               } else if (match->match == SR_TRIGGER_RISING) {
                                        devc->trigger.risingmask |= channelbit;
-                               else {
+                               else {
                                        sr_err("Only rising/falling trigger is "
                                                "supported in 100 and 200MHz mode.");
                                        return SR_ERR;
@@ -1007,13 +1042,16 @@ SR_PRIV int sigma_convert_trigger(const struct sr_dev_inst *sdi)
 static int get_trigger_offset(uint8_t *samples, uint16_t last_sample,
        struct sigma_trigger *t)
 {
+       const uint8_t *rdptr;
        int i;
-       uint16_t sample = 0;
+       uint16_t sample;
 
+       rdptr = samples;
+       sample = 0;
        for (i = 0; i < 8; i++) {
                if (i > 0)
                        last_sample = sample;
-               sample = samples[2 * i] | (samples[2 * i + 1] << 8);
+               sample = read_u16le_inc(&rdptr);
 
                /* Simple triggers. */
                if ((sample & t->simplemask) != t->simplevalue)
@@ -1083,7 +1121,7 @@ static int check_and_submit_sample(struct dev_context *devc,
  */
 static uint16_t sigma_dram_cluster_ts(struct sigma_dram_cluster *cluster)
 {
-       return (cluster->timestamp_hi << 8) | cluster->timestamp_lo;
+       return read_u16le(&cluster->timestamp[0]);
 }
 
 /*
@@ -1091,13 +1129,7 @@ static uint16_t sigma_dram_cluster_ts(struct sigma_dram_cluster *cluster)
  */
 static uint16_t sigma_dram_cluster_data(struct sigma_dram_cluster *cl, int idx)
 {
-       uint16_t sample;
-
-       sample = 0;
-       sample |= cl->samples[idx].sample_lo << 0;
-       sample |= cl->samples[idx].sample_hi << 8;
-       sample = (sample >> 8) | (sample << 8);
-       return sample;
+       return read_u16le(&cl->samples[idx].sample[0]);
 }
 
 /*
@@ -1288,8 +1320,10 @@ static int download_capture(struct sr_dev_inst *sdi)
         */
        sigma_set_register(devc, WRITE_MODE, WMR_FORCESTOP | WMR_SDRAMWRITEEN);
        do {
-               if (sigma_read_register(devc, READ_MODE, &modestatus, 1) != 1) {
-                       sr_err("failed while waiting for RMR_POSTTRIGGERED bit");
+               ret = sigma_read_register(devc, READ_MODE,
+                       &modestatus, sizeof(modestatus));
+               if (ret != sizeof(modestatus)) {
+                       sr_err("Could not poll for post-trigger condition.");
                        return FALSE;
                }
        } while (!(modestatus & RMR_POSTTRIGGERED));
@@ -1301,15 +1335,17 @@ static int download_capture(struct sr_dev_inst *sdi)
        sigma_read_pos(devc, &stoppos, &triggerpos);
 
        /* Check if trigger has fired. */
-       if (sigma_read_register(devc, READ_MODE, &modestatus, 1) != 1) {
-               sr_err("failed to read READ_MODE register");
+       ret = sigma_read_register(devc, READ_MODE,
+               &modestatus, sizeof(modestatus));
+       if (ret != sizeof(modestatus)) {
+               sr_err("Could not query trigger hit.");
                return FALSE;
        }
        trg_line = ~0;
        trg_event = ~0;
        if (modestatus & RMR_TRIGGERED) {
-               trg_line = triggerpos >> 9;
-               trg_event = triggerpos & 0x1ff;
+               trg_line = triggerpos >> ROW_SHIFT;
+               trg_event = triggerpos & ROW_MASK;
        }
 
        /*
@@ -1358,9 +1394,9 @@ static int download_capture(struct sr_dev_inst *sdi)
 
                for (i = 0; i < dl_lines_curr; i++) {
                        uint32_t trigger_event = ~0;
-                       /* The last "DRAM line" can be only partially full. */
+                       /* The last "DRAM line" need not span its full length. */
                        if (dl_lines_done + i == dl_lines_total - 1)
-                               dl_events_in_line = stoppos & 0x1ff;
+                               dl_events_in_line = stoppos & ROW_MASK;
 
                        /* Test if the trigger happened on this line. */
                        if (dl_lines_done + i == trg_line)
@@ -1438,7 +1474,7 @@ static void build_lut_entry(uint16_t value, uint16_t mask, uint16_t *entry)
                entry[i] = 0xffff;
 
                /* For each bit in LUT. */
-               for (j = 0; j < 16; j++)
+               for (j = 0; j < 16; j++) {
 
                        /* For each channel in quad. */
                        for (k = 0; k < 4; k++) {
@@ -1449,6 +1485,7 @@ static void build_lut_entry(uint16_t value, uint16_t mask, uint16_t *entry)
                                                        (!(j & (1 << k)))))
                                        entry[i] &= ~(1 << j);
                        }
+               }
        }
 }