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thodg/cgminer/driver-icarus.c

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  • Author : Kano
    Date : 2013-10-09 14:09:47
    Hash : 39ac69c1
    Message : CMR allow sending flash and clock commands

  • driver-icarus.c
  • /*
     * Copyright 2012-2013 Andrew Smith
     * Copyright 2012 Xiangfu <xiangfu@openmobilefree.com>
     * Copyright 2013 Con Kolivas <kernel@kolivas.org>
     *
     * 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 3 of the License, or (at your option)
     * any later version.  See COPYING for more details.
     */
    
    /*
     * Those code should be works fine with V2 and V3 bitstream of Icarus.
     * Operation:
     *   No detection implement.
     *   Input: 64B = 32B midstate + 20B fill bytes + last 12 bytes of block head.
     *   Return: send back 32bits immediately when Icarus found a valid nonce.
     *           no query protocol implemented here, if no data send back in ~11.3
     *           seconds (full cover time on 32bit nonce range by 380MH/s speed)
     *           just send another work.
     * Notice:
     *   1. Icarus will start calculate when you push a work to them, even they
     *      are busy.
     *   2. The 2 FPGAs on Icarus will distribute the job, one will calculate the
     *      0 ~ 7FFFFFFF, another one will cover the 80000000 ~ FFFFFFFF.
     *   3. It's possible for 2 FPGAs both find valid nonce in the meantime, the 2
     *      valid nonce will all be send back.
     *   4. Icarus will stop work when: a valid nonce has been found or 32 bits
     *      nonce range is completely calculated.
     */
    
    
    #include <float.h>
    #include <limits.h>
    #include <pthread.h>
    #include <stdint.h>
    #include <stdio.h>
    #include <strings.h>
    #include <sys/time.h>
    #include <unistd.h>
    
    #include "config.h"
    
    #ifdef WIN32
    #include <windows.h>
    #endif
    
    #include "compat.h"
    #include "miner.h"
    #include "usbutils.h"
    
    // The serial I/O speed - Linux uses a define 'B115200' in bits/termios.h
    #define ICARUS_IO_SPEED 115200
    
    // The size of a successful nonce read
    #define ICARUS_READ_SIZE 4
    
    #define AMU_PREF_PACKET 256
    #define BLT_PREF_PACKET 512
    #define ICA_PREF_PACKET 256
    
    // Ensure the sizes are correct for the Serial read
    #if (ICARUS_READ_SIZE != 4)
    #error ICARUS_READ_SIZE must be 4
    #endif
    #define ASSERT1(condition) __maybe_unused static char sizeof_uint32_t_must_be_4[(condition)?1:-1]
    ASSERT1(sizeof(uint32_t) == 4);
    
    // TODO: USB? Different calculation? - see usbstats to work it out e.g. 1/2 of normal send time
    //  or even use that number? 1/2
    // #define ICARUS_READ_TIME(baud) ((double)ICARUS_READ_SIZE * (double)8.0 / (double)(baud))
    // maybe 1ms?
    #define ICARUS_READ_TIME(baud) (0.001)
    
    // USB ms timeout to wait - user specified timeouts are multiples of this
    #define ICARUS_WAIT_TIMEOUT 100
    #define ICARUS_CMR2_TIMEOUT 1
    
    // Defined in multiples of ICARUS_WAIT_TIMEOUT
    // Must of course be greater than ICARUS_READ_COUNT_TIMING/ICARUS_WAIT_TIMEOUT
    // There's no need to have this bigger, since the overhead/latency of extra work
    // is pretty small once you get beyond a 10s nonce range time and 10s also
    // means that nothing slower than 429MH/s can go idle so most icarus devices
    // will always mine without idling
    #define ICARUS_READ_TIME_LIMIT_MAX 100
    
    // In timing mode: Default starting value until an estimate can be obtained
    // 5000 ms allows for up to a ~840MH/s device
    #define ICARUS_READ_COUNT_TIMING	5000
    #define ICARUS_READ_COUNT_MIN		ICARUS_WAIT_TIMEOUT
    #define SECTOMS(s)	((int)((s) * 1000))
    // How many ms below the expected completion time to abort work
    // extra in case the last read is delayed
    #define ICARUS_READ_REDUCE	((int)(ICARUS_WAIT_TIMEOUT * 1.5))
    
    // For a standard Icarus REV3 (to 5 places)
    // Since this rounds up a the last digit - it is a slight overestimate
    // Thus the hash rate will be a VERY slight underestimate
    // (by a lot less than the displayed accuracy)
    // Minor inaccuracy of these numbers doesn't affect the work done,
    // only the displayed MH/s
    #define ICARUS_REV3_HASH_TIME 0.0000000026316
    #define LANCELOT_HASH_TIME 0.0000000025000
    #define ASICMINERUSB_HASH_TIME 0.0000000029761
    // TODO: What is it?
    #define CAIRNSMORE1_HASH_TIME 0.0000000027000
    // Per FPGA
    #define CAIRNSMORE2_HASH_TIME 0.0000000066600
    #define NANOSEC 1000000000.0
    
    #define CAIRNSMORE2_INTS 4
    
    // Icarus Rev3 doesn't send a completion message when it finishes
    // the full nonce range, so to avoid being idle we must abort the
    // work (by starting a new work item) shortly before it finishes
    //
    // Thus we need to estimate 2 things:
    //	1) How many hashes were done if the work was aborted
    //	2) How high can the timeout be before the Icarus is idle,
    //		to minimise the number of work items started
    //	We set 2) to 'the calculated estimate' - ICARUS_READ_REDUCE
    //	to ensure the estimate ends before idle
    //
    // The simple calculation used is:
    //	Tn = Total time in seconds to calculate n hashes
    //	Hs = seconds per hash
    //	Xn = number of hashes
    //	W  = code/usb overhead per work
    //
    // Rough but reasonable estimate:
    //	Tn = Hs * Xn + W	(of the form y = mx + b)
    //
    // Thus:
    //	Line of best fit (using least squares)
    //
    //	Hs = (n*Sum(XiTi)-Sum(Xi)*Sum(Ti))/(n*Sum(Xi^2)-Sum(Xi)^2)
    //	W = Sum(Ti)/n - (Hs*Sum(Xi))/n
    //
    // N.B. W is less when aborting work since we aren't waiting for the reply
    //	to be transferred back (ICARUS_READ_TIME)
    //	Calculating the hashes aborted at n seconds is thus just n/Hs
    //	(though this is still a slight overestimate due to code delays)
    //
    
    // Both below must be exceeded to complete a set of data
    // Minimum how long after the first, the last data point must be
    #define HISTORY_SEC 60
    // Minimum how many points a single ICARUS_HISTORY should have
    #define MIN_DATA_COUNT 5
    // The value MIN_DATA_COUNT used is doubled each history until it exceeds:
    #define MAX_MIN_DATA_COUNT 100
    
    static struct timeval history_sec = { HISTORY_SEC, 0 };
    
    // Store the last INFO_HISTORY data sets
    // [0] = current data, not yet ready to be included as an estimate
    // Each new data set throws the last old set off the end thus
    // keeping a ongoing average of recent data
    #define INFO_HISTORY 10
    
    struct ICARUS_HISTORY {
    	struct timeval finish;
    	double sumXiTi;
    	double sumXi;
    	double sumTi;
    	double sumXi2;
    	uint32_t values;
    	uint32_t hash_count_min;
    	uint32_t hash_count_max;
    };
    
    enum timing_mode { MODE_DEFAULT, MODE_SHORT, MODE_LONG, MODE_VALUE };
    
    static const char *MODE_DEFAULT_STR = "default";
    static const char *MODE_SHORT_STR = "short";
    static const char *MODE_SHORT_STREQ = "short=";
    static const char *MODE_LONG_STR = "long";
    static const char *MODE_LONG_STREQ = "long=";
    static const char *MODE_VALUE_STR = "value";
    static const char *MODE_UNKNOWN_STR = "unknown";
    
    struct ICARUS_INFO {
    	enum sub_ident ident;
    	int intinfo;
    
    	// time to calculate the golden_ob
    	uint64_t golden_hashes;
    	struct timeval golden_tv;
    
    	struct ICARUS_HISTORY history[INFO_HISTORY+1];
    	uint32_t min_data_count;
    
    	int timeout;
    
    	// seconds per Hash
    	double Hs;
    	// ms til we abort
    	int read_time;
    	// ms limit for (short=/long=) read_time
    	int read_time_limit;
    
    	enum timing_mode timing_mode;
    	bool do_icarus_timing;
    
    	double fullnonce;
    	int count;
    	double W;
    	uint32_t values;
    	uint64_t hash_count_range;
    
    	// Determine the cost of history processing
    	// (which will only affect W)
    	uint64_t history_count;
    	struct timeval history_time;
    
    	// icarus-options
    	int baud;
    	int work_division;
    	int fpga_count;
    	uint32_t nonce_mask;
    
    	uint8_t cmr2_speed;
    	bool speed_next_work;
    	bool flash_next_work;
    };
    
    #define ICARUS_MIDSTATE_SIZE 32
    #define ICARUS_UNUSED_SIZE 16
    #define ICARUS_WORK_SIZE 12
    
    #define ICARUS_WORK_DATA_OFFSET 64
    
    #define ICARUS_CMR2_SPEED_FACTOR 2.5
    #define ICARUS_CMR2_SPEED_MIN_INT 100
    #define ICARUS_CMR2_SPEED_DEF_INT 180
    #define ICARUS_CMR2_SPEED_MAX_INT 220
    #define CMR2_INT_TO_SPEED(_speed) ((uint8_t)((float)_speed / ICARUS_CMR2_SPEED_FACTOR))
    #define ICARUS_CMR2_SPEED_MIN CMR2_INT_TO_SPEED(ICARUS_CMR2_SPEED_MIN_INT)
    #define ICARUS_CMR2_SPEED_DEF CMR2_INT_TO_SPEED(ICARUS_CMR2_SPEED_DEF_INT)
    #define ICARUS_CMR2_SPEED_MAX CMR2_INT_TO_SPEED(ICARUS_CMR2_SPEED_MAX_INT)
    #define ICARUS_CMR2_SPEED_INC 1
    #define ICARUS_CMR2_SPEED_DEC -1
    #define ICARUS_CMR2_SPEED_FAIL -10
    
    #define ICARUS_CMR2_PREFIX ((uint8_t)0xB7)
    #define ICARUS_CMR2_CMD_SPEED ((uint8_t)0)
    #define ICARUS_CMR2_CMD_FLASH ((uint8_t)1)
    #define ICARUS_CMR2_DATA_FLASH_OFF ((uint8_t)0)
    #define ICARUS_CMR2_DATA_FLASH_ON ((uint8_t)1)
    #define ICARUS_CMR2_CHECK ((uint8_t)0x6D)
    
    struct ICARUS_WORK {
    	uint8_t midstate[ICARUS_MIDSTATE_SIZE];
    	// These 4 bytes are for CMR2 bitstreams that handle MHz adjustment
    	uint8_t check;
    	uint8_t data;
    	uint8_t cmd;
    	uint8_t prefix;
    	uint8_t unused[ICARUS_UNUSED_SIZE];
    	uint8_t work[ICARUS_WORK_SIZE];
    };
    
    #define END_CONDITION 0x0000ffff
    
    // Looking for options in --icarus-timing and --icarus-options:
    //
    // Code increments this each time we start to look at a device
    // However, this means that if other devices are checked by
    // the Icarus code (e.g. Avalon only as at 20130517)
    // they will count in the option offset
    //
    // This, however, is deterministic so that's OK
    //
    // If we were to increment after successfully finding an Icarus
    // that would be random since an Icarus may fail and thus we'd
    // not be able to predict the option order
    //
    // Devices are checked in the order libusb finds them which is ?
    //
    static int option_offset = -1;
    
    /*
    #define ICA_BUFSIZ (0x200)
    
    static void transfer_read(struct cgpu_info *icarus, uint8_t request_type, uint8_t bRequest, uint16_t wValue, uint16_t wIndex, char *buf, int bufsiz, int *amount, enum usb_cmds cmd)
    {
    	int err;
    
    	err = usb_transfer_read(icarus, request_type, bRequest, wValue, wIndex, buf, bufsiz, amount, cmd);
    
    	applog(LOG_DEBUG, "%s: cgid %d %s got err %d",
    			icarus->drv->name, icarus->cgminer_id,
    			usb_cmdname(cmd), err);
    }
    */
    
    static void _transfer(struct cgpu_info *icarus, uint8_t request_type, uint8_t bRequest, uint16_t wValue, uint16_t wIndex, uint32_t *data, int siz, enum usb_cmds cmd)
    {
    	int err;
    
    	err = usb_transfer_data(icarus, request_type, bRequest, wValue, wIndex, data, siz, cmd);
    
    	applog(LOG_DEBUG, "%s: cgid %d %s got err %d",
    			icarus->drv->name, icarus->cgminer_id,
    			usb_cmdname(cmd), err);
    }
    
    #define transfer(icarus, request_type, bRequest, wValue, wIndex, cmd) \
    		_transfer(icarus, request_type, bRequest, wValue, wIndex, NULL, 0, cmd)
    
    static void icarus_initialise(struct cgpu_info *icarus, int baud)
    {
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(icarus->device_data);
    	uint16_t wValue, wIndex;
    	enum sub_ident ident;
    	int interface;
    
    	if (icarus->usbinfo.nodev)
    		return;
    
    	usb_set_cps(icarus, baud / 10);
    	usb_enable_cps(icarus);
    
    	interface = _usb_interface(icarus, info->intinfo);
    	ident = usb_ident(icarus);
    
    	switch (ident) {
    		case IDENT_BLT:
    		case IDENT_LLT:
    		case IDENT_CMR1:
    		case IDENT_CMR2:
    			usb_set_pps(icarus, BLT_PREF_PACKET);
    
    			// Reset
    			transfer(icarus, FTDI_TYPE_OUT, FTDI_REQUEST_RESET, FTDI_VALUE_RESET,
    				 interface, C_RESET);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Latency
    			_usb_ftdi_set_latency(icarus, info->intinfo);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Set data control
    			transfer(icarus, FTDI_TYPE_OUT, FTDI_REQUEST_DATA, FTDI_VALUE_DATA_BLT,
    				 interface, C_SETDATA);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// default to BLT/LLT 115200
    			wValue = FTDI_VALUE_BAUD_BLT;
    			wIndex = FTDI_INDEX_BAUD_BLT;
    
    			if (ident == IDENT_CMR1 || ident == IDENT_CMR2) {
    				switch (baud) {
    					case 115200:
    						wValue = FTDI_VALUE_BAUD_CMR_115;
    						wIndex = FTDI_INDEX_BAUD_CMR_115;
    						break;
    					case 57600:
    						wValue = FTDI_VALUE_BAUD_CMR_57;
    						wIndex = FTDI_INDEX_BAUD_CMR_57;
    						break;
    					default:
    						quit(1, "icarus_intialise() invalid baud (%d) for Cairnsmore1", baud);
    						break;
    				}
    			}
    
    			// Set the baud
    			transfer(icarus, FTDI_TYPE_OUT, FTDI_REQUEST_BAUD, wValue,
    				 (wIndex & 0xff00) | interface, C_SETBAUD);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Set Modem Control
    			transfer(icarus, FTDI_TYPE_OUT, FTDI_REQUEST_MODEM, FTDI_VALUE_MODEM,
    				 interface, C_SETMODEM);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Set Flow Control
    			transfer(icarus, FTDI_TYPE_OUT, FTDI_REQUEST_FLOW, FTDI_VALUE_FLOW,
    				 interface, C_SETFLOW);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Clear any sent data
    			transfer(icarus, FTDI_TYPE_OUT, FTDI_REQUEST_RESET, FTDI_VALUE_PURGE_TX,
    				 interface, C_PURGETX);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Clear any received data
    			transfer(icarus, FTDI_TYPE_OUT, FTDI_REQUEST_RESET, FTDI_VALUE_PURGE_RX,
    				 interface, C_PURGERX);
    			break;
    		case IDENT_ICA:
    			usb_set_pps(icarus, ICA_PREF_PACKET);
    
    			// Set Data Control
    			transfer(icarus, PL2303_CTRL_OUT, PL2303_REQUEST_CTRL, PL2303_VALUE_CTRL,
    				 interface, C_SETDATA);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Set Line Control
    			uint32_t ica_data[2] = { PL2303_VALUE_LINE0, PL2303_VALUE_LINE1 };
    			_transfer(icarus, PL2303_CTRL_OUT, PL2303_REQUEST_LINE, PL2303_VALUE_LINE,
    				 interface, &ica_data[0], PL2303_VALUE_LINE_SIZE, C_SETLINE);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Vendor
    			transfer(icarus, PL2303_VENDOR_OUT, PL2303_REQUEST_VENDOR, PL2303_VALUE_VENDOR,
    				 interface, C_VENDOR);
    			break;
    		case IDENT_AMU:
    			usb_set_pps(icarus, AMU_PREF_PACKET);
    
    			// Enable the UART
    			transfer(icarus, CP210X_TYPE_OUT, CP210X_REQUEST_IFC_ENABLE,
    				 CP210X_VALUE_UART_ENABLE,
    				 interface, C_ENABLE_UART);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Set data control
    			transfer(icarus, CP210X_TYPE_OUT, CP210X_REQUEST_DATA, CP210X_VALUE_DATA,
    				 interface, C_SETDATA);
    
    			if (icarus->usbinfo.nodev)
    				return;
    
    			// Set the baud
    			uint32_t data = CP210X_DATA_BAUD;
    			_transfer(icarus, CP210X_TYPE_OUT, CP210X_REQUEST_BAUD, 0,
    				 interface, &data, sizeof(data), C_SETBAUD);
    			break;
    		default:
    			quit(1, "icarus_intialise() called with invalid %s cgid %i ident=%d",
    				icarus->drv->name, icarus->cgminer_id, ident);
    	}
    }
    
    static void rev(unsigned char *s, size_t l)
    {
    	size_t i, j;
    	unsigned char t;
    
    	for (i = 0, j = l - 1; i < j; i++, j--) {
    		t = s[i];
    		s[i] = s[j];
    		s[j] = t;
    	}
    }
    
    #define ICA_NONCE_ERROR -1
    #define ICA_NONCE_OK 0
    #define ICA_NONCE_RESTART 1
    #define ICA_NONCE_TIMEOUT 2
    
    static int icarus_get_nonce(struct cgpu_info *icarus, unsigned char *buf, struct timeval *tv_start, struct timeval *tv_finish, struct thr_info *thr, int read_time)
    {
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(icarus->device_data);
    	struct timeval read_start, read_finish;
    	int err, amt;
    	int rc = 0, delay;
    	int read_amount = ICARUS_READ_SIZE;
    	bool first = true;
    
    	cgtime(tv_start);
    	while (true) {
    		if (icarus->usbinfo.nodev)
    			return ICA_NONCE_ERROR;
    
    		cgtime(&read_start);
    		err = usb_read_ii_timeout(icarus, info->intinfo,
    					  (char *)buf, read_amount, &amt,
    					  info->timeout, C_GETRESULTS);
    		cgtime(&read_finish);
    		if (err < 0 && err != LIBUSB_ERROR_TIMEOUT) {
    			applog(LOG_ERR, "%s%i: Comms error (rerr=%d amt=%d)",
    					icarus->drv->name, icarus->device_id, err, amt);
    			dev_error(icarus, REASON_DEV_COMMS_ERROR);
    			return ICA_NONCE_ERROR;
    		}
    
    		if (first)
    			copy_time(tv_finish, &read_finish);
    
    		if (amt >= read_amount)
    			return ICA_NONCE_OK;
    
    		rc = SECTOMS(tdiff(&read_finish, tv_start));
    		if (rc >= read_time) {
    			if (amt > 0)
    				applog(LOG_DEBUG, "Icarus Read: Timeout reading for %d ms", rc);
    			else
    				applog(LOG_DEBUG, "Icarus Read: No data for %d ms", rc);
    			return ICA_NONCE_TIMEOUT;
    		}
    
    		if (thr && thr->work_restart) {
    			applog(LOG_DEBUG, "Icarus Read: Work restart at %d ms", rc);
    			return ICA_NONCE_RESTART;
    		}
    
    		if (amt > 0) {
    			buf += amt;
    			read_amount -= amt;
    			first = false;
    		}
    
    		if (info->timeout < ICARUS_WAIT_TIMEOUT) {
    			delay = ICARUS_WAIT_TIMEOUT - rc;
    			if (delay > 0) {
    				cgsleep_ms(delay);
    
    				if (thr && thr->work_restart) {
    					applog(LOG_DEBUG, "Icarus Read: Work restart at %d ms", rc);
    					return ICA_NONCE_RESTART;
    				}
    			}
    		}
    	}
    }
    
    static const char *timing_mode_str(enum timing_mode timing_mode)
    {
    	switch(timing_mode) {
    	case MODE_DEFAULT:
    		return MODE_DEFAULT_STR;
    	case MODE_SHORT:
    		return MODE_SHORT_STR;
    	case MODE_LONG:
    		return MODE_LONG_STR;
    	case MODE_VALUE:
    		return MODE_VALUE_STR;
    	default:
    		return MODE_UNKNOWN_STR;
    	}
    }
    
    static void set_timing_mode(int this_option_offset, struct cgpu_info *icarus)
    {
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(icarus->device_data);
    	enum sub_ident ident;
    	double Hs;
    	char buf[BUFSIZ+1];
    	char *ptr, *comma, *eq;
    	size_t max;
    	int i;
    
    	if (opt_icarus_timing == NULL)
    		buf[0] = '\0';
    	else {
    		ptr = opt_icarus_timing;
    		for (i = 0; i < this_option_offset; i++) {
    			comma = strchr(ptr, ',');
    			if (comma == NULL)
    				break;
    			ptr = comma + 1;
    		}
    
    		comma = strchr(ptr, ',');
    		if (comma == NULL)
    			max = strlen(ptr);
    		else
    			max = comma - ptr;
    
    		if (max > BUFSIZ)
    			max = BUFSIZ;
    		strncpy(buf, ptr, max);
    		buf[max] = '\0';
    	}
    
    	ident = usb_ident(icarus);
    	switch (ident) {
    		case IDENT_ICA:
    			info->Hs = ICARUS_REV3_HASH_TIME;
    			break;
    		case IDENT_BLT:
    		case IDENT_LLT:
    			info->Hs = LANCELOT_HASH_TIME;
    			break;
    		case IDENT_AMU:
    			info->Hs = ASICMINERUSB_HASH_TIME;
    			break;
    		case IDENT_CMR1:
    			info->Hs = CAIRNSMORE1_HASH_TIME;
    			break;
    		case IDENT_CMR2:
    			info->Hs = CAIRNSMORE2_HASH_TIME;
    			break;
    		default:
    			quit(1, "Icarus get_options() called with invalid %s ident=%d",
    				icarus->drv->name, ident);
    	}
    
    	info->read_time = 0;
    	info->read_time_limit = 0; // 0 = no limit
    
    	if (strcasecmp(buf, MODE_SHORT_STR) == 0) {
    		// short
    		info->read_time = ICARUS_READ_COUNT_TIMING;
    
    		info->timing_mode = MODE_SHORT;
    		info->do_icarus_timing = true;
    	} else if (strncasecmp(buf, MODE_SHORT_STREQ, strlen(MODE_SHORT_STREQ)) == 0) {
    		// short=limit
    		info->read_time = ICARUS_READ_COUNT_TIMING;
    
    		info->timing_mode = MODE_SHORT;
    		info->do_icarus_timing = true;
    
    		info->read_time_limit = atoi(&buf[strlen(MODE_SHORT_STREQ)]);
    		if (info->read_time_limit < 0)
    			info->read_time_limit = 0;
    		if (info->read_time_limit > ICARUS_READ_TIME_LIMIT_MAX)
    			info->read_time_limit = ICARUS_READ_TIME_LIMIT_MAX;
    	} else if (strcasecmp(buf, MODE_LONG_STR) == 0) {
    		// long
    		info->read_time = ICARUS_READ_COUNT_TIMING;
    
    		info->timing_mode = MODE_LONG;
    		info->do_icarus_timing = true;
    	} else if (strncasecmp(buf, MODE_LONG_STREQ, strlen(MODE_LONG_STREQ)) == 0) {
    		// long=limit
    		info->read_time = ICARUS_READ_COUNT_TIMING;
    
    		info->timing_mode = MODE_LONG;
    		info->do_icarus_timing = true;
    
    		info->read_time_limit = atoi(&buf[strlen(MODE_LONG_STREQ)]);
    		if (info->read_time_limit < 0)
    			info->read_time_limit = 0;
    		if (info->read_time_limit > ICARUS_READ_TIME_LIMIT_MAX)
    			info->read_time_limit = ICARUS_READ_TIME_LIMIT_MAX;
    	} else if ((Hs = atof(buf)) != 0) {
    		// ns[=read_time]
    		info->Hs = Hs / NANOSEC;
    		info->fullnonce = info->Hs * (((double)0xffffffff) + 1);
    
    		if ((eq = strchr(buf, '=')) != NULL)
    			info->read_time = atoi(eq+1) * ICARUS_WAIT_TIMEOUT;
    
    		if (info->read_time < ICARUS_READ_COUNT_MIN)
    			info->read_time = SECTOMS(info->fullnonce) - ICARUS_READ_REDUCE;
    
    		if (unlikely(info->read_time < ICARUS_READ_COUNT_MIN))
    			info->read_time = ICARUS_READ_COUNT_MIN;
    
    		info->timing_mode = MODE_VALUE;
    		info->do_icarus_timing = false;
    	} else {
    		// Anything else in buf just uses DEFAULT mode
    
    		info->fullnonce = info->Hs * (((double)0xffffffff) + 1);
    
    		if ((eq = strchr(buf, '=')) != NULL)
    			info->read_time = atoi(eq+1) * ICARUS_WAIT_TIMEOUT;
    
    		if (info->read_time < ICARUS_READ_COUNT_MIN)
    			info->read_time = SECTOMS(info->fullnonce) - ICARUS_READ_REDUCE;
    
    		if (unlikely(info->read_time < ICARUS_READ_COUNT_MIN))
    			info->read_time = ICARUS_READ_COUNT_MIN;
    
    		info->timing_mode = MODE_DEFAULT;
    		info->do_icarus_timing = false;
    	}
    
    	info->min_data_count = MIN_DATA_COUNT;
    
    	// All values are in multiples of ICARUS_WAIT_TIMEOUT
    	info->read_time_limit *= ICARUS_WAIT_TIMEOUT;
    
    	applog(LOG_DEBUG, "%s: cgid %d Init: mode=%s read_time=%dms limit=%dms Hs=%e",
    			icarus->drv->name, icarus->cgminer_id,
    			timing_mode_str(info->timing_mode),
    			info->read_time, info->read_time_limit, info->Hs);
    }
    
    static uint32_t mask(int work_division)
    {
    	uint32_t nonce_mask = 0x7fffffff;
    
    	// yes we can calculate these, but this way it's easy to see what they are
    	switch (work_division) {
    	case 1:
    		nonce_mask = 0xffffffff;
    		break;
    	case 2:
    		nonce_mask = 0x7fffffff;
    		break;
    	case 4:
    		nonce_mask = 0x3fffffff;
    		break;
    	case 8:
    		nonce_mask = 0x1fffffff;
    		break;
    	default:
    		quit(1, "Invalid2 icarus-options for work_division (%d) must be 1, 2, 4 or 8", work_division);
    	}
    
    	return nonce_mask;
    }
    
    static void get_options(int this_option_offset, struct cgpu_info *icarus, int *baud, int *work_division, int *fpga_count)
    {
    	char buf[BUFSIZ+1];
    	char *ptr, *comma, *colon, *colon2;
    	enum sub_ident ident;
    	size_t max;
    	int i, tmp;
    
    	if (opt_icarus_options == NULL)
    		buf[0] = '\0';
    	else {
    		ptr = opt_icarus_options;
    		for (i = 0; i < this_option_offset; i++) {
    			comma = strchr(ptr, ',');
    			if (comma == NULL)
    				break;
    			ptr = comma + 1;
    		}
    
    		comma = strchr(ptr, ',');
    		if (comma == NULL)
    			max = strlen(ptr);
    		else
    			max = comma - ptr;
    
    		if (max > BUFSIZ)
    			max = BUFSIZ;
    		strncpy(buf, ptr, max);
    		buf[max] = '\0';
    	}
    
    	ident = usb_ident(icarus);
    	switch (ident) {
    		case IDENT_ICA:
    		case IDENT_BLT:
    		case IDENT_LLT:
    			*baud = ICARUS_IO_SPEED;
    			*work_division = 2;
    			*fpga_count = 2;
    			break;
    		case IDENT_AMU:
    			*baud = ICARUS_IO_SPEED;
    			*work_division = 1;
    			*fpga_count = 1;
    			break;
    		case IDENT_CMR1:
    			*baud = ICARUS_IO_SPEED;
    			*work_division = 2;
    			*fpga_count = 2;
    			break;
    		case IDENT_CMR2:
    			*baud = ICARUS_IO_SPEED;
    			*work_division = 1;
    			*fpga_count = 1;
    			break;
    		default:
    			quit(1, "Icarus get_options() called with invalid %s ident=%d",
    				icarus->drv->name, ident);
    	}
    
    	if (*buf) {
    		colon = strchr(buf, ':');
    		if (colon)
    			*(colon++) = '\0';
    
    		if (*buf) {
    			tmp = atoi(buf);
    			switch (tmp) {
    			case 115200:
    				*baud = 115200;
    				break;
    			case 57600:
    				*baud = 57600;
    				break;
    			default:
    				quit(1, "Invalid icarus-options for baud (%s) must be 115200 or 57600", buf);
    			}
    		}
    
    		if (colon && *colon) {
    			colon2 = strchr(colon, ':');
    			if (colon2)
    				*(colon2++) = '\0';
    
    			if (*colon) {
    				tmp = atoi(colon);
    				if (tmp == 1 || tmp == 2 || tmp == 4 || tmp == 8) {
    					*work_division = tmp;
    					*fpga_count = tmp;	// default to the same
    				} else {
    					quit(1, "Invalid icarus-options for work_division (%s) must be 1, 2, 4 or 8", colon);
    				}
    			}
    
    			if (colon2 && *colon2) {
    				tmp = atoi(colon2);
    				if (tmp > 0 && tmp <= *work_division)
    					*fpga_count = tmp;
    				else {
    					quit(1, "Invalid icarus-options for fpga_count (%s) must be >0 and <=work_division (%d)", colon2, *work_division);
    				}
    			}
    		}
    	}
    }
    
    static bool icarus_detect_one(struct libusb_device *dev, struct usb_find_devices *found)
    {
    	int this_option_offset = ++option_offset;
    	struct ICARUS_INFO *info;
    	struct timeval tv_start, tv_finish;
    
    	// Block 171874 nonce = (0xa2870100) = 0x000187a2
    	// N.B. golden_ob MUST take less time to calculate
    	//	than the timeout set in icarus_open()
    	//	This one takes ~0.53ms on Rev3 Icarus
    	const char golden_ob[] =
    		"4679ba4ec99876bf4bfe086082b40025"
    		"4df6c356451471139a3afa71e48f544a"
    		"00000000000000000000000000000000"
    		"0000000087320b1a1426674f2fa722ce";
    
    	const char golden_nonce[] = "000187a2";
    	const uint32_t golden_nonce_val = 0x000187a2;
    	unsigned char nonce_bin[ICARUS_READ_SIZE];
    	struct ICARUS_WORK workdata;
    	char *nonce_hex;
    	int baud, uninitialised_var(work_division), uninitialised_var(fpga_count);
    	struct cgpu_info *icarus;
    	int ret, err, amount, tries, i;
    	bool ok;
    	bool cmr2_ok[CAIRNSMORE2_INTS];
    	int cmr2_count;
    
    	if ((sizeof(workdata) << 1) != (sizeof(golden_ob) - 1))
    		quithere(1, "Data and golden_ob sizes don't match");
    
    	icarus = usb_alloc_cgpu(&icarus_drv, 1);
    
    	if (!usb_init(icarus, dev, found))
    		goto shin;
    
    	usb_buffer_enable(icarus);
    
    	get_options(this_option_offset, icarus, &baud, &work_division, &fpga_count);
    
    	hex2bin((void *)(&workdata), golden_ob, sizeof(workdata));
    
    	info = (struct ICARUS_INFO *)calloc(1, sizeof(struct ICARUS_INFO));
    	if (unlikely(!info))
    		quit(1, "Failed to malloc ICARUS_INFO");
    	icarus->device_data = (void *)info;
    
    	info->ident = usb_ident(icarus);
    	switch (info->ident) {
    		case IDENT_ICA:
    		case IDENT_BLT:
    		case IDENT_LLT:
    		case IDENT_AMU:
    		case IDENT_CMR1:
    			info->timeout = ICARUS_WAIT_TIMEOUT;
    			break;
    		case IDENT_CMR2:
    			if (found->intinfo_count != CAIRNSMORE2_INTS) {
    				quithere(1, "CMR2 Interface count (%d) isn't expected: %d",
    						found->intinfo_count,
    						CAIRNSMORE2_INTS);
    			}
    			info->timeout = ICARUS_CMR2_TIMEOUT;
    			cmr2_count = 0;
    			for (i = 0; i < CAIRNSMORE2_INTS; i++)
    				cmr2_ok[i] = false;
    			break;
    		default:
    			quit(1, "%s icarus_detect_one() invalid %s ident=%d",
    				icarus->drv->dname, icarus->drv->dname, info->ident);
    	}
    
    // For CMR2 test each USB Interface
    
    cmr2_retry:
    
    	tries = 2;
    	ok = false;
    	while (!ok && tries-- > 0) {
    		icarus_initialise(icarus, baud);
    
    		err = usb_write_ii(icarus, info->intinfo,
    				   (char *)(&workdata), sizeof(workdata), &amount, C_SENDWORK);
    
    		if (err != LIBUSB_SUCCESS || amount != sizeof(workdata))
    			continue;
    
    		memset(nonce_bin, 0, sizeof(nonce_bin));
    		ret = icarus_get_nonce(icarus, nonce_bin, &tv_start, &tv_finish, NULL, 100);
    		if (ret != ICA_NONCE_OK)
    			continue;
    
    		nonce_hex = bin2hex(nonce_bin, sizeof(nonce_bin));
    		if (strncmp(nonce_hex, golden_nonce, 8) == 0)
    			ok = true;
    		else {
    			if (tries < 0 && info->ident != IDENT_CMR2) {
    				applog(LOG_ERR,
    					"Icarus Detect: "
    					"Test failed at %s: get %s, should: %s",
    					icarus->device_path, nonce_hex, golden_nonce);
    			}
    		}
    		free(nonce_hex);
    	}
    
    	if (!ok) {
    		if (info->ident != IDENT_CMR2)
    			goto unshin;
    
    		if (info->intinfo < CAIRNSMORE2_INTS-1) {
    			info->intinfo++;
    			goto cmr2_retry;
    		}
    	} else {
    		if (info->ident == IDENT_CMR2) {
    			applog(LOG_DEBUG,
    				"Icarus Detect: "
    				"Test succeeded at %s i%d: got %s",
    					icarus->device_path, info->intinfo, golden_nonce);
    
    			cmr2_ok[info->intinfo] = true;
    			cmr2_count++;
    			if (info->intinfo < CAIRNSMORE2_INTS-1) {
    				info->intinfo++;
    				goto cmr2_retry;
    			}
    		}
    	}
    
    	if (info->ident == IDENT_CMR2) {
    		if (cmr2_count == 0) {
    			applog(LOG_ERR,
    				"Icarus Detect: Test failed at %s: for all %d CMR2 Interfaces",
    				icarus->device_path, CAIRNSMORE2_INTS);
    			goto unshin;
    		}
    
    		// set the interface to the first one that succeeded
    		for (i = 0; i < CAIRNSMORE2_INTS; i++)
    			if (cmr2_ok[i]) {
    				info->intinfo = i;
    				break;
    			}
    	} else {
    		applog(LOG_DEBUG,
    			"Icarus Detect: "
    			"Test succeeded at %s: got %s",
    				icarus->device_path, golden_nonce);
    	}
    
    	/* We have a real Icarus! */
    	if (!add_cgpu(icarus))
    		goto unshin;
    
    	update_usb_stats(icarus);
    
    	applog(LOG_INFO, "%s%d: Found at %s",
    		icarus->drv->name, icarus->device_id, icarus->device_path);
    
    	if (info->ident == IDENT_CMR2) {
    		applog(LOG_INFO, "%s%d: with %d Interface%s",
    				icarus->drv->name, icarus->device_id,
    				cmr2_count, cmr2_count > 1 ? "s" : "");
    
    		// Assume 1 or 2 are running FPGA pairs
    		if (cmr2_count < 3) {
    			work_division = fpga_count = 2;
    			info->Hs /= 2;
    		}
    	}
    
    	applog(LOG_DEBUG, "%s%d: Init baud=%d work_division=%d fpga_count=%d",
    		icarus->drv->name, icarus->device_id, baud, work_division, fpga_count);
    
    	info->baud = baud;
    	info->work_division = work_division;
    	info->fpga_count = fpga_count;
    	info->nonce_mask = mask(work_division);
    
    	info->golden_hashes = (golden_nonce_val & info->nonce_mask) * fpga_count;
    	timersub(&tv_finish, &tv_start, &(info->golden_tv));
    
    	set_timing_mode(this_option_offset, icarus);
    	
    	if (info->ident == IDENT_CMR2) {
    		int i;
    		for (i = info->intinfo + 1; i < icarus->usbdev->found->intinfo_count; i++) {
    			struct cgpu_info *cgtmp;
    			struct ICARUS_INFO *intmp;
    
    			if (!cmr2_ok[i])
    				continue;
    
    			cgtmp = usb_copy_cgpu(icarus);
    			if (!cgtmp) {
    				applog(LOG_ERR, "%s%d: Init failed initinfo %d",
    						icarus->drv->name, icarus->device_id, i);
    				continue;
    			}
    
    			cgtmp->usbinfo.usbstat = USB_NOSTAT;
    
    			intmp = (struct ICARUS_INFO *)malloc(sizeof(struct ICARUS_INFO));
    			if (unlikely(!intmp))
    				quit(1, "Failed2 to malloc ICARUS_INFO");
    
    			cgtmp->device_data = (void *)intmp;
    
    			// Initialise everything to match
    			memcpy(intmp, info, sizeof(struct ICARUS_INFO));
    
    			intmp->intinfo = i;
    
    			icarus_initialise(cgtmp, baud);
    
    			if (!add_cgpu(cgtmp)) {
    				usb_uninit(cgtmp);
    				free(intmp);
    				continue;
    			}
    
    			update_usb_stats(cgtmp);
    		}
    	}
    
    	return true;
    
    unshin:
    
    	usb_uninit(icarus);
    	free(info);
    	icarus->device_data = NULL;
    
    shin:
    
    	icarus = usb_free_cgpu(icarus);
    
    	return false;
    }
    
    static void icarus_detect(bool __maybe_unused hotplug)
    {
    	usb_detect(&icarus_drv, icarus_detect_one);
    }
    
    static bool icarus_prepare(__maybe_unused struct thr_info *thr)
    {
    //	struct cgpu_info *icarus = thr->cgpu;
    
    	return true;
    }
    
    static void cmr2_command(struct cgpu_info *icarus, uint8_t cmd, uint8_t data)
    {
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(icarus->device_data);
    	struct ICARUS_WORK workdata;
    	int amount;
    
    	memset((void *)(&workdata), 0, sizeof(workdata));
    
    	workdata.prefix = ICARUS_CMR2_PREFIX;
    	workdata.cmd = cmd;
    	workdata.data = data;
    	workdata.check = workdata.data ^ workdata.cmd ^ workdata.prefix ^ ICARUS_CMR2_CHECK;
    
    	usb_write_ii(icarus, info->intinfo, (char *)(&workdata), sizeof(workdata), &amount, C_SENDWORK);
    }
    
    static void cmr2_commands(struct cgpu_info *icarus)
    {
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(icarus->device_data);
    
    	if (info->speed_next_work) {
    		info->speed_next_work = false;
    		cmr2_command(icarus, ICARUS_CMR2_CMD_SPEED, info->cmr2_speed);
    		return;
    	}
    
    	if (info->flash_next_work) {
    		info->flash_next_work = false;
    		cmr2_command(icarus, ICARUS_CMR2_CMD_FLASH, ICARUS_CMR2_DATA_FLASH_ON);
    		cgsleep_ms(250);
    		cmr2_command(icarus, ICARUS_CMR2_CMD_FLASH, ICARUS_CMR2_DATA_FLASH_OFF);
    		cgsleep_ms(250);
    		cmr2_command(icarus, ICARUS_CMR2_CMD_FLASH, ICARUS_CMR2_DATA_FLASH_ON);
    		cgsleep_ms(250);
    		cmr2_command(icarus, ICARUS_CMR2_CMD_FLASH, ICARUS_CMR2_DATA_FLASH_OFF);
    		return;
    	}
    }
    
    static int64_t icarus_scanhash(struct thr_info *thr, struct work *work,
    				__maybe_unused int64_t max_nonce)
    {
    	struct cgpu_info *icarus = thr->cgpu;
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(icarus->device_data);
    	int ret, err, amount;
    	unsigned char nonce_bin[ICARUS_READ_SIZE];
    	struct ICARUS_WORK workdata;
    	char *ob_hex;
    	uint32_t nonce;
    	int64_t hash_count;
    	struct timeval tv_start, tv_finish, elapsed;
    	struct timeval tv_history_start, tv_history_finish;
    	double Ti, Xi;
    	int curr_hw_errors, i;
    	bool was_hw_error;
    
    	struct ICARUS_HISTORY *history0, *history;
    	int count;
    	double Hs, W, fullnonce;
    	int read_time;
    	bool limited;
    	int64_t estimate_hashes;
    	uint32_t values;
    	int64_t hash_count_range;
    
    	// Device is gone
    	if (icarus->usbinfo.nodev)
    		return -1;
    
    	elapsed.tv_sec = elapsed.tv_usec = 0;
    
    	memset((void *)(&workdata), 0, sizeof(workdata));
    	memcpy(&(workdata.midstate), work->midstate, ICARUS_MIDSTATE_SIZE);
    	memcpy(&(workdata.work), work->data + ICARUS_WORK_DATA_OFFSET, ICARUS_WORK_SIZE);
    	rev((void *)(&(workdata.midstate)), ICARUS_MIDSTATE_SIZE);
    	rev((void *)(&(workdata.work)), ICARUS_WORK_SIZE);
    
    	if (info->speed_next_work || info->flash_next_work)
    		cmr2_commands(icarus);
    
    	// We only want results for the work we are about to send
    	usb_buffer_clear(icarus);
    
    	err = usb_write_ii(icarus, info->intinfo, (char *)(&workdata), sizeof(workdata), &amount, C_SENDWORK);
    	if (err < 0 || amount != sizeof(workdata)) {
    		applog(LOG_ERR, "%s%i: Comms error (werr=%d amt=%d)",
    				icarus->drv->name, icarus->device_id, err, amount);
    		dev_error(icarus, REASON_DEV_COMMS_ERROR);
    		icarus_initialise(icarus, info->baud);
    		return 0;
    	}
    
    	if (opt_debug) {
    		ob_hex = bin2hex((void *)(&workdata), sizeof(workdata));
    		applog(LOG_DEBUG, "%s%d: sent %s",
    			icarus->drv->name, icarus->device_id, ob_hex);
    		free(ob_hex);
    	}
    
    	/* Icarus will return 4 bytes (ICARUS_READ_SIZE) nonces or nothing */
    	memset(nonce_bin, 0, sizeof(nonce_bin));
    	ret = icarus_get_nonce(icarus, nonce_bin, &tv_start, &tv_finish, thr, info->read_time);
    	if (ret == ICA_NONCE_ERROR)
    		return 0;
    
    	work->blk.nonce = 0xffffffff;
    
    	// aborted before becoming idle, get new work
    	if (ret == ICA_NONCE_TIMEOUT || ret == ICA_NONCE_RESTART) {
    		timersub(&tv_finish, &tv_start, &elapsed);
    
    		// ONLY up to just when it aborted
    		// We didn't read a reply so we don't subtract ICARUS_READ_TIME
    		estimate_hashes = ((double)(elapsed.tv_sec)
    					+ ((double)(elapsed.tv_usec))/((double)1000000)) / info->Hs;
    
    		// If some Serial-USB delay allowed the full nonce range to
    		// complete it can't have done more than a full nonce
    		if (unlikely(estimate_hashes > 0xffffffff))
    			estimate_hashes = 0xffffffff;
    
    		applog(LOG_DEBUG, "%s%d: no nonce = 0x%08lX hashes (%ld.%06lds)",
    				icarus->drv->name, icarus->device_id,
    				(long unsigned int)estimate_hashes,
    				elapsed.tv_sec, elapsed.tv_usec);
    
    		return estimate_hashes;
    	}
    
    	memcpy((char *)&nonce, nonce_bin, sizeof(nonce_bin));
    	nonce = htobe32(nonce);
    	curr_hw_errors = icarus->hw_errors;
    	submit_nonce(thr, work, nonce);
    	was_hw_error = (curr_hw_errors > icarus->hw_errors);
    
    	hash_count = (nonce & info->nonce_mask);
    	hash_count++;
    	hash_count *= info->fpga_count;
    
    #if 0
    	// This appears to only return zero nonce values
    	if (usb_buffer_size(icarus) > 3) {
    		memcpy((char *)&nonce, icarus->usbdev->buffer, sizeof(nonce_bin));
    		nonce = htobe32(nonce);
    		applog(LOG_WARNING, "%s%d: attempting to submit 2nd nonce = 0x%08lX",
    				icarus->drv->name, icarus->device_id,
    				(long unsigned int)nonce);
    		curr_hw_errors = icarus->hw_errors;
    		submit_nonce(thr, work, nonce);
    		was_hw_error = (curr_hw_errors > icarus->hw_errors);
    	}
    #endif
    
    	if (opt_debug || info->do_icarus_timing)
    		timersub(&tv_finish, &tv_start, &elapsed);
    
    	applog(LOG_DEBUG, "%s%d: nonce = 0x%08x = 0x%08lX hashes (%ld.%06lds)",
    			icarus->drv->name, icarus->device_id,
    			nonce, (long unsigned int)hash_count,
    			elapsed.tv_sec, elapsed.tv_usec);
    
    	// Ignore possible end condition values ... and hw errors
    	// TODO: set limitations on calculated values depending on the device
    	// to avoid crap values caused by CPU/Task Switching/Swapping/etc
    	if (info->do_icarus_timing
    	&&  !was_hw_error
    	&&  ((nonce & info->nonce_mask) > END_CONDITION)
    	&&  ((nonce & info->nonce_mask) < (info->nonce_mask & ~END_CONDITION))) {
    		cgtime(&tv_history_start);
    
    		history0 = &(info->history[0]);
    
    		if (history0->values == 0)
    			timeradd(&tv_start, &history_sec, &(history0->finish));
    
    		Ti = (double)(elapsed.tv_sec)
    			+ ((double)(elapsed.tv_usec))/((double)1000000)
    			- ((double)ICARUS_READ_TIME(info->baud));
    		Xi = (double)hash_count;
    		history0->sumXiTi += Xi * Ti;
    		history0->sumXi += Xi;
    		history0->sumTi += Ti;
    		history0->sumXi2 += Xi * Xi;
    
    		history0->values++;
    
    		if (history0->hash_count_max < hash_count)
    			history0->hash_count_max = hash_count;
    		if (history0->hash_count_min > hash_count || history0->hash_count_min == 0)
    			history0->hash_count_min = hash_count;
    
    		if (history0->values >= info->min_data_count
    		&&  timercmp(&tv_start, &(history0->finish), >)) {
    			for (i = INFO_HISTORY; i > 0; i--)
    				memcpy(&(info->history[i]),
    					&(info->history[i-1]),
    					sizeof(struct ICARUS_HISTORY));
    
    			// Initialise history0 to zero for summary calculation
    			memset(history0, 0, sizeof(struct ICARUS_HISTORY));
    
    			// We just completed a history data set
    			// So now recalc read_time based on the whole history thus we will
    			// initially get more accurate until it completes INFO_HISTORY
    			// total data sets
    			count = 0;
    			for (i = 1 ; i <= INFO_HISTORY; i++) {
    				history = &(info->history[i]);
    				if (history->values >= MIN_DATA_COUNT) {
    					count++;
    
    					history0->sumXiTi += history->sumXiTi;
    					history0->sumXi += history->sumXi;
    					history0->sumTi += history->sumTi;
    					history0->sumXi2 += history->sumXi2;
    					history0->values += history->values;
    
    					if (history0->hash_count_max < history->hash_count_max)
    						history0->hash_count_max = history->hash_count_max;
    					if (history0->hash_count_min > history->hash_count_min || history0->hash_count_min == 0)
    						history0->hash_count_min = history->hash_count_min;
    				}
    			}
    
    			// All history data
    			Hs = (history0->values*history0->sumXiTi - history0->sumXi*history0->sumTi)
    				/ (history0->values*history0->sumXi2 - history0->sumXi*history0->sumXi);
    			W = history0->sumTi/history0->values - Hs*history0->sumXi/history0->values;
    			hash_count_range = history0->hash_count_max - history0->hash_count_min;
    			values = history0->values;
    			
    			// Initialise history0 to zero for next data set
    			memset(history0, 0, sizeof(struct ICARUS_HISTORY));
    
    			fullnonce = W + Hs * (((double)0xffffffff) + 1);
    			read_time = SECTOMS(fullnonce) - ICARUS_READ_REDUCE;
    			if (info->read_time_limit > 0 && read_time > info->read_time_limit) {
    				read_time = info->read_time_limit;
    				limited = true;
    			} else
    				limited = false;
    
    			info->Hs = Hs;
    			info->read_time = read_time;
    
    			info->fullnonce = fullnonce;
    			info->count = count;
    			info->W = W;
    			info->values = values;
    			info->hash_count_range = hash_count_range;
    
    			if (info->min_data_count < MAX_MIN_DATA_COUNT)
    				info->min_data_count *= 2;
    			else if (info->timing_mode == MODE_SHORT)
    				info->do_icarus_timing = false;
    
    			applog(LOG_WARNING, "%s%d Re-estimate: Hs=%e W=%e read_time=%dms%s fullnonce=%.3fs",
    					icarus->drv->name, icarus->device_id, Hs, W, read_time,
    					limited ? " (limited)" : "", fullnonce);
    		}
    		info->history_count++;
    		cgtime(&tv_history_finish);
    
    		timersub(&tv_history_finish, &tv_history_start, &tv_history_finish);
    		timeradd(&tv_history_finish, &(info->history_time), &(info->history_time));
    	}
    
    	return hash_count;
    }
    
    static struct api_data *icarus_api_stats(struct cgpu_info *cgpu)
    {
    	struct api_data *root = NULL;
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(cgpu->device_data);
    
    	// Warning, access to these is not locked - but we don't really
    	// care since hashing performance is way more important than
    	// locking access to displaying API debug 'stats'
    	// If locking becomes an issue for any of them, use copy_data=true also
    	root = api_add_int(root, "read_time", &(info->read_time), false);
    	root = api_add_int(root, "read_time_limit", &(info->read_time_limit), false);
    	root = api_add_double(root, "fullnonce", &(info->fullnonce), false);
    	root = api_add_int(root, "count", &(info->count), false);
    	root = api_add_hs(root, "Hs", &(info->Hs), false);
    	root = api_add_double(root, "W", &(info->W), false);
    	root = api_add_uint(root, "total_values", &(info->values), false);
    	root = api_add_uint64(root, "range", &(info->hash_count_range), false);
    	root = api_add_uint64(root, "history_count", &(info->history_count), false);
    	root = api_add_timeval(root, "history_time", &(info->history_time), false);
    	root = api_add_uint(root, "min_data_count", &(info->min_data_count), false);
    	root = api_add_uint(root, "timing_values", &(info->history[0].values), false);
    	root = api_add_const(root, "timing_mode", timing_mode_str(info->timing_mode), false);
    	root = api_add_bool(root, "is_timing", &(info->do_icarus_timing), false);
    	root = api_add_int(root, "baud", &(info->baud), false);
    	root = api_add_int(root, "work_division", &(info->work_division), false);
    	root = api_add_int(root, "fpga_count", &(info->fpga_count), false);
    
    	return root;
    }
    
    static void icarus_statline_before(char *buf, size_t bufsiz, struct cgpu_info *cgpu)
    {
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(cgpu->device_data);
    
    	if (info->ident == IDENT_CMR2 && info->cmr2_speed > 0)
    		tailsprintf(buf, bufsiz, "%5.1fMhz", (float)(info->cmr2_speed) * ICARUS_CMR2_SPEED_FACTOR);
    	else
    		tailsprintf(buf, bufsiz, "        ");
    
    	tailsprintf(buf, bufsiz, "        | ");
    }
    
    static void icarus_shutdown(__maybe_unused struct thr_info *thr)
    {
    	// TODO: ?
    }
    
    static void icarus_identify(struct cgpu_info *cgpu)
    {
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(cgpu->device_data);
    
    	if (info->ident == IDENT_CMR2)
    		info->flash_next_work = true;
    }
    
    static char *icarus_set(struct cgpu_info *cgpu, char *option, char *setting, char *replybuf)
    {
    	struct ICARUS_INFO *info = (struct ICARUS_INFO *)(cgpu->device_data);
    	int val;
    
    	if (info->ident != IDENT_CMR2) {
    		strcpy(replybuf, "no set options available");
    		return replybuf;
    	}
    
    	if (strcasecmp(option, "help") == 0) {
    		sprintf(replybuf, "clock: range %d-%d",
    				  ICARUS_CMR2_SPEED_MIN_INT, ICARUS_CMR2_SPEED_MAX_INT);
    		return replybuf;
    	}
    
    	if (strcasecmp(option, "clock") == 0) {
    		if (!setting || !*setting) {
    			sprintf(replybuf, "missing clock setting");
    			return replybuf;
    		}
    
    		val = atoi(setting);
    		if (val < ICARUS_CMR2_SPEED_MIN_INT || val > ICARUS_CMR2_SPEED_MAX_INT) {
    			sprintf(replybuf, "invalid clock: '%s' valid range %d-%d",
    					  setting,
    					  ICARUS_CMR2_SPEED_MIN_INT,
    					  ICARUS_CMR2_SPEED_MAX_INT);
    		}
    
    		info->cmr2_speed = CMR2_INT_TO_SPEED(val);
    		info->speed_next_work = true;
    
    		return NULL;
    	}
    
    	sprintf(replybuf, "Unknown option: %s", option);
    	return replybuf;
    }
    
    struct device_drv icarus_drv = {
    	.drv_id = DRIVER_icarus,
    	.dname = "Icarus",
    	.name = "ICA",
    	.drv_detect = icarus_detect,
    	.get_api_stats = icarus_api_stats,
    	.get_statline_before = icarus_statline_before,
    	.set_device = icarus_set,
    	.identify_device = icarus_identify,
    	.thread_prepare = icarus_prepare,
    	.scanhash = icarus_scanhash,
    	.thread_shutdown = icarus_shutdown,
    };