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thodg/cgminer/driver-modminer.c

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  • Author : Kano
    Date : 2013-02-13 11:13:30
    Hash : b9968156
    Message : MMQ rewrite the last of the old scanhash loop and drastically reduce CPU

  • driver-modminer.c
  • /*
     * Copyright 2012-2013 Andrew Smith
     * Copyright 2012 Luke Dashjr
     *
     * 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.
     */
    
    #include "config.h"
    
    #include <stdarg.h>
    #include <stdio.h>
    #include <unistd.h>
    #include <math.h>
    
    #include "logging.h"
    #include "miner.h"
    #include "usbutils.h"
    #include "fpgautils.h"
    #include "util.h"
    
    #define BITSTREAM_FILENAME "fpgaminer_top_fixed7_197MHz.ncd"
    #define BISTREAM_USER_ID "\2\4$B"
    
    #define BITSTREAM_MAGIC_0 0
    #define BITSTREAM_MAGIC_1 9
    
    #define MODMINER_CUTOFF_TEMP 60.0
    #define MODMINER_OVERHEAT_TEMP 50.0
    #define MODMINER_RECOVER_TEMP 46.5
    #define MODMINER_TEMP_UP_LIMIT 47.0
    
    #define MODMINER_HW_ERROR_PERCENT 0.75
    
    // How many seconds of no nonces means there's something wrong
    // First time - drop the clock and see if it revives
    // Second time - (and it didn't revive) disable it
    #define ITS_DEAD_JIM 300
    
    // N.B. in the latest firmware the limit is 250
    // however the voltage/temperature risks preclude that
    #define MODMINER_MAX_CLOCK 230
    #define MODMINER_DEF_CLOCK 200
    #define MODMINER_MIN_CLOCK 160
    
    #define MODMINER_CLOCK_UP 2
    #define MODMINER_CLOCK_SET 0
    #define MODMINER_CLOCK_DOWN -2
    // = 0 means OVERHEAT doesn't affect the clock
    #define MODMINER_CLOCK_OVERHEAT 0
    #define MODMINER_CLOCK_DEAD -6
    #define MODMINER_CLOCK_CUTOFF -10
    
    // Commands
    #define MODMINER_PING "\x00"
    #define MODMINER_GET_VERSION "\x01"
    #define MODMINER_FPGA_COUNT "\x02"
    // Commands + require FPGAid
    #define MODMINER_GET_IDCODE '\x03'
    #define MODMINER_GET_USERCODE '\x04'
    #define MODMINER_PROGRAM '\x05'
    #define MODMINER_SET_CLOCK '\x06'
    #define MODMINER_READ_CLOCK '\x07'
    #define MODMINER_SEND_WORK '\x08'
    #define MODMINER_CHECK_WORK '\x09'
    // One byte temperature reply
    #define MODMINER_TEMP1 '\x0a'
    // Two byte temperature reply
    #define MODMINER_TEMP2 '\x0d'
    
    // +6 bytes
    #define MODMINER_SET_REG '\x0b'
    // +2 bytes
    #define MODMINER_GET_REG '\x0c'
    
    #define FPGAID_ALL 4
    
    // Maximum how many good shares in a row means clock up
    // 96 is ~34m22s at 200MH/s
    #define MODMINER_TRY_UP 96
    // Initially how many good shares in a row means clock up
    // This is doubled each down clock until it reaches MODMINER_TRY_UP
    // 6 is ~2m9s at 200MH/s
    #define MODMINER_EARLY_UP 6
    // Limit when reducing shares_to_good
    #define MODMINER_MIN_BACK 12
    
    struct device_drv modminer_drv;
    
    // 45 noops sent when detecting, in case the device was left in "start job" reading
    static const char NOOP[] = MODMINER_PING "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff";
    
    static void do_ping(struct cgpu_info *modminer)
    {
    	char buf[0x100+1];
    	int err, amount;
    
    	// Don't care if it fails
    	err = usb_write(modminer, (char *)NOOP, sizeof(NOOP)-1, &amount, C_PING);
    	applog(LOG_DEBUG, "%s%u: flush noop got %d err %d",
    		modminer->drv->name, modminer->fpgaid, amount, err);
    
    	// Clear any outstanding data
    	while ((err = usb_read(modminer, buf, sizeof(buf)-1, &amount, C_CLEAR)) == 0 && amount > 0)
    		applog(LOG_DEBUG, "%s%u: clear got %d",
    			modminer->drv->name, modminer->fpgaid, amount);
    
    	applog(LOG_DEBUG, "%s%u: final clear got %d err %d",
    		modminer->drv->name, modminer->fpgaid, amount, err);
    }
    
    static bool modminer_detect_one(struct libusb_device *dev, struct usb_find_devices *found)
    {
    	char buf[0x100+1];
    	char *devname = NULL;
    	char devpath[20];
    	int err, i, amount;
    	bool added = false;
    
    	struct cgpu_info *modminer = NULL;
    	modminer = calloc(1, sizeof(*modminer));
    	modminer->drv = &modminer_drv;
    	modminer->modminer_mutex = calloc(1, sizeof(*(modminer->modminer_mutex)));
    	mutex_init(modminer->modminer_mutex);
    	modminer->fpgaid = (char)0;
    
    	if (!usb_init(modminer, dev, found)) {
    		applog(LOG_ERR, "%s detect (%d:%d) failed to initialise (incorrect device?)",
    			modminer->drv->dname,
    			(int)(modminer->usbinfo.bus_number),
    			(int)(modminer->usbinfo.device_address));
    		goto shin;
    	}
    
    	sprintf(devpath, "%d:%d",
    			(int)(modminer->usbinfo.bus_number),
    			(int)(modminer->usbinfo.device_address));
    
    	do_ping(modminer);
    
    	if ((err = usb_write(modminer, MODMINER_GET_VERSION, 1, &amount, C_REQUESTVERSION)) < 0 || amount != 1) {
    		applog(LOG_ERR, "%s detect (%s) send version request failed (%d:%d)",
    			modminer->drv->dname, devpath, amount, err);
    		goto unshin;
    	}
    
    	if ((err = usb_read(modminer, buf, sizeof(buf)-1, &amount, C_GETVERSION)) < 0 || amount < 1) {
    		if (err < 0)
    			applog(LOG_ERR, "%s detect (%s) no version reply (%d)",
    				modminer->drv->dname, devpath, err);
    		else
    			applog(LOG_ERR, "%s detect (%s) empty version reply (%d)",
    				modminer->drv->dname, devpath, amount);
    
    		applog(LOG_DEBUG, "%s detect (%s) check the firmware",
    				modminer->drv->dname, devpath);
    
    		goto unshin;
    	}
    	buf[amount] = '\0';
    	devname = strdup(buf);
    	applog(LOG_DEBUG, "%s (%s) identified as: %s", modminer->drv->dname, devpath, devname);
    
    	if ((err = usb_write(modminer, MODMINER_FPGA_COUNT, 1, &amount, C_REQUESTFPGACOUNT) < 0 || amount != 1)) {
    		applog(LOG_ERR, "%s detect (%s) FPGA count request failed (%d:%d)",
    			modminer->drv->dname, devpath, amount, err);
    		goto unshin;
    	}
    
    	if ((err = usb_read(modminer, buf, 1, &amount, C_GETFPGACOUNT)) < 0 || amount != 1) {
    		applog(LOG_ERR, "%s detect (%s) no FPGA count reply (%d:%d)",
    			modminer->drv->dname, devpath, amount, err);
    		goto unshin;
    	}
    
    	// TODO: flag it use 1 byte temp if it is an old firmware
    	// can detect with modminer->cgusb->serial ?
    
    	if (buf[0] == 0) {
    		applog(LOG_ERR, "%s detect (%s) zero FPGA count from %s",
    			modminer->drv->dname, devpath, devname);
    		goto unshin;
    	}
    
    	if (buf[0] < 1 || buf[0] > 4) {
    		applog(LOG_ERR, "%s detect (%s) invalid FPGA count (%u) from %s",
    			modminer->drv->dname, devpath, buf[0], devname);
    		goto unshin;
    	}
    
    	applog(LOG_DEBUG, "%s (%s) %s has %u FPGAs",
    		modminer->drv->dname, devpath, devname, buf[0]);
    
    	modminer->name = devname;
    
    	// TODO: test with 1 board missing in the middle and each end
    	// to see how that affects the sequence numbers
    	for (i = 0; i < buf[0]; i++) {
    		struct cgpu_info *tmp = calloc(1, sizeof(*tmp));
    
    		tmp->drv = copy_drv(modminer->drv);
    		tmp->name = devname;
    
    		sprintf(devpath, "%d:%d:%d",
    			(int)(modminer->usbinfo.bus_number),
    			(int)(modminer->usbinfo.device_address),
    			i);
    
    		tmp->device_path = strdup(devpath);
    		tmp->usbdev = modminer->usbdev;
    		tmp->usbinfo.bus_number = modminer->usbinfo.bus_number;
    		tmp->usbinfo.device_address = modminer->usbinfo.device_address;
    		// Only the first copy gets the already used stats
    		if (!added)
    			tmp->usbinfo.usbstat = modminer->usbinfo.usbstat;
    		tmp->fpgaid = (char)i;
    		tmp->modminer_mutex = modminer->modminer_mutex;
    		tmp->deven = DEV_ENABLED;
    		tmp->threads = 1;
    
    		if (!add_cgpu(tmp)) {
    			free(tmp->device_path);
    			if (tmp->drv->copy)
    				free(tmp->drv);
    			free(tmp);
    			goto unshin;
    		}
    
    		update_usb_stats(tmp);
    
    		added = true;
    	}
    
    	if (modminer->drv->copy)
    		free(modminer->drv);
    
    	free(modminer);
    
    	return true;
    
    unshin:
    	if (!added)
    		usb_uninit(modminer);
    
    shin:
    	if (!added)
    		free(modminer->modminer_mutex);
    
    	if (modminer->drv->copy)
    		free(modminer->drv);
    
    	free(modminer);
    
    	if (added)
    		return true;
    	else
    		return false;
    }
    
    static void modminer_detect()
    {
    	usb_detect(&modminer_drv, modminer_detect_one);
    }
    
    static bool get_expect(struct cgpu_info *modminer, FILE *f, char c)
    {
    	char buf;
    
    	if (fread(&buf, 1, 1, f) != 1) {
    		applog(LOG_ERR, "%s%u: Error (%d) reading bitstream (%c)",
    				modminer->drv->name, modminer->device_id, errno, c);
    		return false;
    	}
    
    	if (buf != c) {
    		applog(LOG_ERR, "%s%u: bitstream code mismatch (%c)",
    				modminer->drv->name, modminer->device_id, c);
    		return false;
    	}
    
    	return true;
    }
    
    static bool get_info(struct cgpu_info *modminer, FILE *f, char *buf, int bufsiz, const char *name)
    {
    	unsigned char siz[2];
    	int len;
    
    	if (fread(siz, 2, 1, f) != 1) {
    		applog(LOG_ERR, "%s%u: Error (%d) reading bitstream '%s' len",
    			modminer->drv->name, modminer->device_id, errno, name);
    		return false;
    	}
    
    	len = siz[0] * 256 + siz[1];
    
    	if (len >= bufsiz) {
    		applog(LOG_ERR, "%s%u: Bitstream '%s' len too large (%d)",
    			modminer->drv->name, modminer->device_id, name, len);
    		return false;
    	}
    
    	if (fread(buf, len, 1, f) != 1) {
    		applog(LOG_ERR, "%s%u: Error (%d) reading bitstream '%s'", errno,
    			modminer->drv->name, modminer->device_id, errno, name);
    		return false;
    	}
    
    	buf[len] = '\0';
    
    	return true;
    }
    
    #define USE_DEFAULT_TIMEOUT 0
    
    // mutex must always be locked before calling
    static bool get_status_timeout(struct cgpu_info *modminer, char *msg, unsigned int timeout, enum usb_cmds cmd)
    {
    	int err, amount;
    	char buf[1];
    
    	if (timeout == USE_DEFAULT_TIMEOUT)
    		err = usb_read(modminer, buf, 1, &amount, cmd);
    	else
    		err = usb_read_timeout(modminer, buf, 1, &amount, timeout, cmd);
    
    	if (err < 0 || amount != 1) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error (%d:%d) getting %s reply",
    			modminer->drv->name, modminer->device_id, amount, err, msg);
    
    		return false;
    	}
    
    	if (buf[0] != 1) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error, invalid %s reply (was %d should be 1)",
    			modminer->drv->name, modminer->device_id, msg, buf[0]);
    
    		return false;
    	}
    
    	return true;
    }
    
    // mutex must always be locked before calling
    static bool get_status(struct cgpu_info *modminer, char *msg, enum usb_cmds cmd)
    {
    	return get_status_timeout(modminer, msg, USE_DEFAULT_TIMEOUT, cmd);
    }
    
    static bool modminer_fpga_upload_bitstream(struct cgpu_info *modminer)
    {
    	const char *bsfile = BITSTREAM_FILENAME;
    	char buf[0x100], *p;
    	char devmsg[64];
    	unsigned char *ubuf = (unsigned char *)buf;
    	unsigned long totlen, len;
    	size_t buflen, remaining;
    	float nextmsg, upto;
    	char fpgaid = FPGAID_ALL;
    	int err, amount, tries;
    	char *ptr;
    
    	FILE *f = open_bitstream("modminer", bsfile);
    	if (!f) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error (%d) opening bitstream file %s",
    			modminer->drv->name, modminer->device_id, errno, bsfile);
    
    		return false;
    	}
    
    	if (fread(buf, 2, 1, f) != 1) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error (%d) reading bitstream magic",
    			modminer->drv->name, modminer->device_id, errno);
    
    		goto dame;
    	}
    
    	if (buf[0] != BITSTREAM_MAGIC_0 || buf[1] != BITSTREAM_MAGIC_1) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: bitstream has incorrect magic (%u,%u) instead of (%u,%u)",
    			modminer->drv->name, modminer->device_id,
    			buf[0], buf[1],
    			BITSTREAM_MAGIC_0, BITSTREAM_MAGIC_1);
    
    		goto dame;
    	}
    
    	if (fseek(f, 11L, SEEK_CUR)) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error (%d) bitstream seek failed",
    			modminer->drv->name, modminer->device_id, errno);
    
    		goto dame;
    	}
    
    	if (!get_expect(modminer, f, 'a'))
    		goto undame;
    
    	if (!get_info(modminer, f, buf, sizeof(buf), "Design name"))
    		goto undame;
    
    	applog(LOG_DEBUG, "%s%u: bitstream file '%s' info:",
    		modminer->drv->name, modminer->device_id, bsfile);
    
    	applog(LOG_DEBUG, " Design name: '%s'", buf);
    
    	p = strrchr(buf, ';') ? : buf;
    	p = strrchr(buf, '=') ? : p;
    	if (p[0] == '=')
    		p++;
    
    	unsigned long fwusercode = (unsigned long)strtoll(p, &p, 16);
    
    	if (p[0] != '\0') {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Bad usercode in bitstream file",
    			modminer->drv->name, modminer->device_id);
    
    		goto dame;
    	}
    
    	if (fwusercode == 0xffffffff) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: bitstream doesn't support user code",
    			modminer->drv->name, modminer->device_id);
    
    		goto dame;
    	}
    
    	applog(LOG_DEBUG, " Version: %u, build %u", (fwusercode >> 8) & 0xff, fwusercode & 0xff);
    
    	if (!get_expect(modminer, f, 'b'))
    		goto undame;
    
    	if (!get_info(modminer, f, buf, sizeof(buf), "Part number"))
    		goto undame;
    
    	applog(LOG_DEBUG, " Part number: '%s'", buf);
    
    	if (!get_expect(modminer, f, 'c'))
    		goto undame;
    
    	if (!get_info(modminer, f, buf, sizeof(buf), "Build date"))
    		goto undame;
    
    	applog(LOG_DEBUG, " Build date: '%s'", buf);
    
    	if (!get_expect(modminer, f, 'd'))
    		goto undame;
    
    	if (!get_info(modminer, f, buf, sizeof(buf), "Build time"))
    		goto undame;
    
    	applog(LOG_DEBUG, " Build time: '%s'", buf);
    
    	if (!get_expect(modminer, f, 'e'))
    		goto undame;
    
    	if (fread(buf, 4, 1, f) != 1) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error (%d) reading bitstream data len",
    			modminer->drv->name, modminer->device_id, errno);
    
    		goto dame;
    	}
    
    	len = ((unsigned long)ubuf[0] << 24) | ((unsigned long)ubuf[1] << 16) | (ubuf[2] << 8) | ubuf[3];
    	applog(LOG_DEBUG, " Bitstream size: %lu", len);
    
    	strcpy(devmsg, modminer->device_path);
    	ptr = strrchr(devmsg, ':');
    	if (ptr)
    		*ptr = '\0';
    
    	applog(LOG_WARNING, "%s%u: Programming all FPGA on %s ... Mining will not start until complete",
    		modminer->drv->name, modminer->device_id, devmsg);
    
    	buf[0] = MODMINER_PROGRAM;
    	buf[1] = fpgaid;
    	buf[2] = (len >>  0) & 0xff;
    	buf[3] = (len >>  8) & 0xff;
    	buf[4] = (len >> 16) & 0xff;
    	buf[5] = (len >> 24) & 0xff;
    
    	if ((err = usb_write(modminer, buf, 6, &amount, C_STARTPROGRAM)) < 0 || amount != 6) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Program init failed (%d:%d)",
    			modminer->drv->name, modminer->device_id, amount, err);
    
    		goto dame;
    	}
    
    	if (!get_status(modminer, "initialise", C_STARTPROGRAMSTATUS))
    		goto undame;
    
    // It must be 32 bytes according to MCU legacy.c
    #define WRITE_SIZE 32
    
    	totlen = len;
    	nextmsg = 0.1;
    	while (len > 0) {
    		buflen = len < WRITE_SIZE ? len : WRITE_SIZE;
    		if (fread(buf, buflen, 1, f) != 1) {
    			mutex_unlock(modminer->modminer_mutex);
    
    			applog(LOG_ERR, "%s%u: bitstream file read error %d (%d bytes left)",
    				modminer->drv->name, modminer->device_id, errno, len);
    
    			goto dame;
    		}
    
    		tries = 0;
    		ptr = buf;
    		remaining = buflen;
    		while ((err = usb_write(modminer, ptr, remaining, &amount, C_PROGRAM)) < 0 || amount != (int)remaining) {
    			if (err == LIBUSB_ERROR_TIMEOUT && amount > 0 && ++tries < 4) {
    				remaining -= amount;
    				ptr += amount;
    
    				if (opt_debug)
    					applog(LOG_DEBUG, "%s%u: Program timeout (%d:%d) sent %d tries %d",
    						modminer->drv->name, modminer->device_id,
    						amount, err, remaining, tries);
    
    				if (!get_status(modminer, "write status", C_PROGRAMSTATUS2))
    					goto dame;
    
    			} else {
    				mutex_unlock(modminer->modminer_mutex);
    
    				applog(LOG_ERR, "%s%u: Program failed (%d:%d) sent %d",
    					modminer->drv->name, modminer->device_id, amount, err, remaining);
    
    				goto dame;
    			}
    		}
    
    		if (!get_status(modminer, "write status", C_PROGRAMSTATUS))
    			goto dame;
    
    		len -= buflen;
    
    		upto = (float)(totlen - len) / (float)(totlen);
    		if (upto >= nextmsg) {
    			applog(LOG_WARNING,
    				"%s%u: Programming %.1f%% (%d out of %d)",
    				modminer->drv->name, modminer->device_id, upto*100, (totlen - len), totlen);
    
    			nextmsg += 0.1;
    		}
    	}
    
    	if (!get_status(modminer, "final status", C_FINALPROGRAMSTATUS))
    		goto undame;
    
    	applog(LOG_WARNING, "%s%u: Programming completed for all FPGA on %s",
    		modminer->drv->name, modminer->device_id, devmsg);
    
    	// Give it a 2/3s delay after programming
    	nmsleep(666);
    
    	return true;
    undame:
    	;
    	mutex_unlock(modminer->modminer_mutex);
    	;
    dame:
    	fclose(f);
    	return false;
    }
    
    static bool modminer_fpga_prepare(struct thr_info *thr)
    {
    	struct cgpu_info *modminer = thr->cgpu;
    	struct timeval now;
    
    	gettimeofday(&now, NULL);
    	get_datestamp(modminer->init, &now);
    
    	struct modminer_fpga_state *state;
    	state = thr->cgpu_data = calloc(1, sizeof(struct modminer_fpga_state));
    	state->shares_to_good = MODMINER_EARLY_UP;
    	state->overheated = false;
    
    	return true;
    }
    
    /*
     * Clocking rules:
     *	If device exceeds cutoff or overheat temp - stop sending work until it cools
     *		decrease the clock by MODMINER_CLOCK_CUTOFF/MODMINER_CLOCK_OVERHEAT
     *		for when it restarts
     *		with MODMINER_CLOCK_OVERHEAT=0 basically says that temp shouldn't
     *		affect the clock unless we reach CUTOFF
     *
     *	If device overheats
     *		set shares_to_good back to MODMINER_MIN_BACK
     *		to speed up clock recovery if temp drop doesnt help
     *
     * When to clock down:
     *	If device gets MODMINER_HW_ERROR_PERCENT errors since last clock up or down
     *		if clock is <= default it requires 2 HW to do this test
     *		if clock is > default it only requires 1 HW to do this test
     *			also double shares_to_good
     *
     * When to clock up:
     *	If device gets shares_to_good good shares in a row
     *		and temp < MODMINER_TEMP_UP_LIMIT
     *
     * N.B. clock must always be a multiple of 2
     */
    static const char *clocknodev = "clock failed - no device";
    static const char *clockoldwork = "clock already changed for this work";
    static const char *clocktoolow = "clock too low";
    static const char *clocktoohi = "clock too high";
    static const char *clocksetfail = "clock set command failed";
    static const char *clockreplyfail = "clock reply failed";
    
    static const char *modminer_delta_clock(struct thr_info *thr, int delta, bool temp, bool force)
    {
    	struct cgpu_info *modminer = thr->cgpu;
    	struct modminer_fpga_state *state = thr->cgpu_data;
    	unsigned char cmd[6], buf[1];
    	int err, amount;
    
    	// Device is gone
    	if (modminer->usbinfo.nodev)
    		return clocknodev;
    
    	// Only do once if multiple shares per work or multiple reasons
    	if (!state->new_work && !force)
    		return clockoldwork;
    
    	state->new_work = false;
    
    	state->shares = 0;
    	state->shares_last_hw = 0;
    	state->hw_errors = 0;
    
    	// FYI clock drop has little effect on temp
    	if (delta < 0 && (modminer->clock + delta) < MODMINER_MIN_CLOCK)
    		return clocktoolow;
    
    	if (delta > 0 && (modminer->clock + delta) > MODMINER_MAX_CLOCK)
    		return clocktoohi;
    
    	if (delta < 0) {
    		if (temp)
    			state->shares_to_good = MODMINER_MIN_BACK;
    		else {
    			if ((state->shares_to_good * 2) < MODMINER_TRY_UP)
    				state->shares_to_good *= 2;
    			else
    				state->shares_to_good = MODMINER_TRY_UP;
    		}
    	}
    
    	modminer->clock += delta;
    
    	cmd[0] = MODMINER_SET_CLOCK;
    	cmd[1] = modminer->fpgaid;
    	cmd[2] = modminer->clock;
    	cmd[3] = cmd[4] = cmd[5] = '\0';
    
    	mutex_lock(modminer->modminer_mutex);
    
    	if ((err = usb_write(modminer, (char *)cmd, 6, &amount, C_SETCLOCK)) < 0 || amount != 6) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error writing set clock speed (%d:%d)",
    			modminer->drv->name, modminer->device_id, amount, err);
    
    		return clocksetfail;
    	}
    
    	if ((err = usb_read(modminer, (char *)(&buf), 1, &amount, C_REPLYSETCLOCK)) < 0 || amount != 1) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error reading set clock speed (%d:%d)",
    			modminer->drv->name, modminer->device_id, amount, err);
    
    		return clockreplyfail;
    	}
    
    	mutex_unlock(modminer->modminer_mutex);
    
    	applog(LOG_WARNING, "%s%u: Set clock speed %sto %u",
    			modminer->drv->name, modminer->device_id,
    			(delta < 0) ? "down " : (delta > 0 ? "up " : ""),
    			modminer->clock);
    
    	return NULL;
    }
    
    static bool modminer_fpga_init(struct thr_info *thr)
    {
    	struct cgpu_info *modminer = thr->cgpu;
    	unsigned char cmd[2], buf[4];
    	int err, amount;
    
    	mutex_lock(modminer->modminer_mutex);
    
    	cmd[0] = MODMINER_GET_USERCODE;
    	cmd[1] = modminer->fpgaid;
    	if ((err = usb_write(modminer, (char *)cmd, 2, &amount, C_REQUESTUSERCODE)) < 0 || amount != 2) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error requesting USER code (%d:%d)",
    			modminer->drv->name, modminer->device_id, amount, err);
    
    		return false;
    	}
    
    	if ((err = usb_read(modminer, (char *)buf, 4, &amount, C_GETUSERCODE)) < 0 || amount != 4) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Error reading USER code (%d:%d)",
    			modminer->drv->name, modminer->device_id, amount, err);
    
    		return false;
    	}
    
    	if (memcmp(buf, BISTREAM_USER_ID, 4)) {
    		applog(LOG_ERR, "%s%u: FPGA not programmed",
    			modminer->drv->name, modminer->device_id);
    
    		if (!modminer_fpga_upload_bitstream(modminer))
    			return false;
    
    		mutex_unlock(modminer->modminer_mutex);
    	} else {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_DEBUG, "%s%u: FPGA is already programmed :)",
    			modminer->drv->name, modminer->device_id);
    	}
    
    	modminer->clock = MODMINER_DEF_CLOCK;
    	modminer_delta_clock(thr, MODMINER_CLOCK_SET, false, false);
    
    	thr->primary_thread = true;
    
    	return true;
    }
    
    static void get_modminer_statline_before(char *buf, struct cgpu_info *modminer)
    {
    	char info[64];
    
    	sprintf(info, " %s%.1fC %3uMHz  | ",
    			(modminer->temp < 10) ? " " : "",
    			modminer->temp,
    			(unsigned int)(modminer->clock));
    
    	strcat(buf, info);
    }
    
    static bool modminer_start_work(struct thr_info *thr, struct work *work)
    {
    	struct cgpu_info *modminer = thr->cgpu;
    	struct modminer_fpga_state *state = thr->cgpu_data;
    	int err, amount;
    	char cmd[48];
    	bool sta;
    
    	cmd[0] = MODMINER_SEND_WORK;
    	cmd[1] = modminer->fpgaid;
    	memcpy(&cmd[2], work->midstate, 32);
    	memcpy(&cmd[34], work->data + 64, 12);
    
    	if (state->first_work.tv_sec == 0)
    		gettimeofday(&state->first_work, NULL);
    
    	if (state->last_nonce.tv_sec == 0)
    		gettimeofday(&state->last_nonce, NULL);
    
    	mutex_lock(modminer->modminer_mutex);
    
    	if ((err = usb_write(modminer, cmd, 46, &amount, C_SENDWORK)) < 0 || amount != 46) {
    		mutex_unlock(modminer->modminer_mutex);
    
    		applog(LOG_ERR, "%s%u: Start work failed (%d:%d)",
    			modminer->drv->name, modminer->device_id, amount, err);
    
    		return false;
    	}
    
    	gettimeofday(&state->tv_workstart, NULL);
    
    	sta = get_status(modminer, "start work", C_SENDWORKSTATUS);
    
    	if (sta) {
    		mutex_unlock(modminer->modminer_mutex);
    		state->new_work = true;
    	}
    
    	return sta;
    }
    
    static void check_temperature(struct thr_info *thr)
    {
    	struct cgpu_info *modminer = thr->cgpu;
    	struct modminer_fpga_state *state = thr->cgpu_data;
    	char cmd[2], temperature[2];
    	int tbytes, tamount;
    	int amount;
    
    	// Device is gone
    	if (modminer->usbinfo.nodev)
    		return;
    
    	if (state->one_byte_temp) {
    		cmd[0] = MODMINER_TEMP1;
    		tbytes = 1;
    	} else {
    		cmd[0] = MODMINER_TEMP2;
    		tbytes = 2;
    	}
    
    	cmd[1] = modminer->fpgaid;
    
    	mutex_lock(modminer->modminer_mutex);
    	if (usb_write(modminer, (char *)cmd, 2, &amount, C_REQUESTTEMPERATURE) == 0 && amount == 2 &&
    	    usb_read(modminer, (char *)(&temperature), tbytes, &tamount, C_GETTEMPERATURE) == 0 && tamount == tbytes) {
    		mutex_unlock(modminer->modminer_mutex);
    		if (state->one_byte_temp)
    			modminer->temp = temperature[0];
    		else {
    			// Only accurate to 2 and a bit places
    			modminer->temp = roundf((temperature[1] * 256.0 + temperature[0]) / 0.128) / 1000.0;
    
    			state->tried_two_byte_temp = true;
    		}
    
    		if (state->overheated) {
    			// Limit recovery to lower than OVERHEAT so it doesn't just go straight over again
    			if (modminer->temp < MODMINER_RECOVER_TEMP) {
    				state->overheated = false;
    				applog(LOG_WARNING, "%s%u: Recovered, temp less than (%.1f) now %.3f",
    					modminer->drv->name, modminer->device_id,
    					MODMINER_RECOVER_TEMP, modminer->temp);
    			}
    		}
    		else if (modminer->temp >= MODMINER_OVERHEAT_TEMP) {
    			if (modminer->temp >= MODMINER_CUTOFF_TEMP) {
    				applog(LOG_WARNING, "%s%u: Hit thermal cutoff limit! (%.1f) at %.3f",
    					modminer->drv->name, modminer->device_id,
    					MODMINER_CUTOFF_TEMP, modminer->temp);
    
    				modminer_delta_clock(thr, MODMINER_CLOCK_CUTOFF, true, false);
    				state->overheated = true;
    				dev_error(modminer, REASON_DEV_THERMAL_CUTOFF);
    			} else {
    				applog(LOG_WARNING, "%s%u: Overheat limit (%.1f) reached %.3f",
    					modminer->drv->name, modminer->device_id,
    					MODMINER_OVERHEAT_TEMP, modminer->temp);
    
    				// If it's defined to be 0 then don't call modminer_delta_clock()
    				if (MODMINER_CLOCK_OVERHEAT != 0)
    					modminer_delta_clock(thr, MODMINER_CLOCK_OVERHEAT, true, false);
    				state->overheated = true;
    				dev_error(modminer, REASON_DEV_OVER_HEAT);
    			}
    		}
    	} else {
    		mutex_unlock(modminer->modminer_mutex);
    
    		if (!state->tried_two_byte_temp) {
    			state->tried_two_byte_temp = true;
    			state->one_byte_temp = true;
    		}
    	}
    }
    
    #define work_restart(thr)  thr->work_restart
    
    // 250Mhz is 17.17s - ensure we don't go idle
    static const double processtime = 17.0;
    // 160Mhz is 26.84 - when overheated ensure we don't throw away shares
    static const double overheattime = 26.9;
    
    static uint64_t modminer_process_results(struct thr_info *thr, struct work *work)
    {
    	struct cgpu_info *modminer = thr->cgpu;
    	struct modminer_fpga_state *state = thr->cgpu_data;
    	struct timeval now;
    	char cmd[2];
    	uint32_t nonce;
    	uint32_t curr_hw_errors;
    	int err, amount, amount2;
    	int timeoutloop;
    	double timeout;
    	int temploop;
    
    	// Device is gone
    	if (modminer->usbinfo.nodev)
    		return -1;
    
    	// If we are overheated it will just keep checking for results
    	// since we can't stop the work
    	// The next work will not start until the temp drops
    	check_temperature(thr);
    
    	cmd[0] = MODMINER_CHECK_WORK;
    	cmd[1] = modminer->fpgaid;
    
    	timeoutloop = 0;
    	temploop = 0;
    	while (0x80085) {
    		mutex_lock(modminer->modminer_mutex);
    		if ((err = usb_write(modminer, cmd, 2, &amount, C_REQUESTWORKSTATUS)) < 0 || amount != 2) {
    			mutex_unlock(modminer->modminer_mutex);
    
    			// timeoutloop never resets so the timeouts can't
    			// accumulate much during a single item of work
    			if (err == LIBUSB_ERROR_TIMEOUT && ++timeoutloop < 5) {
    				state->timeout_fail++;
    				goto tryagain;
    			}
    
    			applog(LOG_ERR, "%s%u: Error sending (get nonce) (%d:%d)",
    				modminer->drv->name, modminer->device_id, amount, err);
    
    			return -1;
    		}
    
    		err = usb_read(modminer, (char *)(&nonce), 4, &amount, C_GETWORKSTATUS);
    		while (err == LIBUSB_SUCCESS && amount < 4) {
    			size_t remain = 4 - amount;
    			char *pos = ((char *)(&nonce)) + amount;
    
    			state->success_more++;
    
    			err = usb_read(modminer, pos, remain, &amount2, C_GETWORKSTATUS);
    
    			amount += amount2;
    		}
    		mutex_unlock(modminer->modminer_mutex);
    
    		if (err < 0 || amount < 4) {
    			// timeoutloop never resets so the timeouts can't
    			// accumulate much during a single item of work
    			if (err == LIBUSB_ERROR_TIMEOUT && ++timeoutloop < 10) {
    				state->timeout_fail++;
    				goto tryagain;
    			}
    
    			applog(LOG_ERR, "%s%u: Error reading (get nonce) (%d:%d)",
    				modminer->drv->name, modminer->device_id, amount+amount2, err);
    		}
    
    		if (memcmp(&nonce, "\xff\xff\xff\xff", 4)) {
    			// found 'something' ...
    			state->shares++;
    			curr_hw_errors = state->hw_errors;
    			submit_nonce(thr, work, nonce);
    			if (state->hw_errors > curr_hw_errors) {
    				gettimeofday(&now, NULL);
    				// Ignore initial errors that often happen
    				if (tdiff(&now, &state->first_work) < 2.0) {
    					state->shares = 0;
    					state->shares_last_hw = 0;
    					state->hw_errors = 0;
    				} else {
    					state->shares_last_hw = state->shares;
    					if (modminer->clock > MODMINER_DEF_CLOCK || state->hw_errors > 1) {
    						float pct = (state->hw_errors * 100.0 / (state->shares ? : 1.0));
    						if (pct >= MODMINER_HW_ERROR_PERCENT)
    							modminer_delta_clock(thr, MODMINER_CLOCK_DOWN, false, false);
    					}
    				}
    			} else {
    				gettimeofday(&state->last_nonce, NULL);
    				state->death_stage_one = false;
    				// If we've reached the required good shares in a row then clock up
    				if (((state->shares - state->shares_last_hw) >= state->shares_to_good) &&
    						modminer->temp < MODMINER_TEMP_UP_LIMIT)
    					modminer_delta_clock(thr, MODMINER_CLOCK_UP, false, false);
    			}
    		} else {
    			// on rare occasions - the MMQ can just stop returning valid nonces
    			double death = ITS_DEAD_JIM * (state->death_stage_one ? 2.0 : 1.0);
    			gettimeofday(&now, NULL);
    			if (tdiff(&now, &state->last_nonce) >= death) {
    				if (state->death_stage_one) {
    					modminer_delta_clock(thr, MODMINER_CLOCK_DEAD, false, true);
    					applog(LOG_ERR, "%s%u: DEATH clock down",
    						modminer->drv->name, modminer->device_id);
    
    					// reset the death info and DISABLE it
    					state->last_nonce.tv_sec = 0;
    					state->last_nonce.tv_usec = 0;
    					state->death_stage_one = false;
    					return -1;
    				} else {
    					modminer_delta_clock(thr, MODMINER_CLOCK_DEAD, false, true);
    					applog(LOG_ERR, "%s%u: death clock down",
    						modminer->drv->name, modminer->device_id);
    
    					state->death_stage_one = true;
    				}
    			}
    		}
    
    tryagain:
    
    		if (work_restart(thr))
    			break;
    
    		if (state->overheated == true) {
    			// don't check every time (every ~1/2 sec)
    			if (++temploop > 4) {
    				check_temperature(thr);
    				temploop = 0;
    			}
    
    		}
    
    		if (state->overheated == true)
    			timeout = overheattime;
    		else
    			timeout = processtime;
    
    		gettimeofday(&now, NULL);
    		if (tdiff(&now, &state->tv_workstart) > timeout)
    			break;
    
    		// 1/10th sec to lower CPU usage
    		nmsleep(100);
    		if (work_restart(thr))
    			break;
    	}
    
    	struct timeval tv_workend, elapsed;
    	gettimeofday(&tv_workend, NULL);
    	timersub(&tv_workend, &state->tv_workstart, &elapsed);
    
    	// Not exact since the clock may have changed ... but close enough I guess
    	uint64_t hashes = (uint64_t)modminer->clock * (((uint64_t)elapsed.tv_sec * 1000000) + elapsed.tv_usec);
    	// Overheat will complete the nonce range
    	if (hashes > 0xffffffff)
    		hashes = 0xffffffff;
    
    	work->blk.nonce = 0xffffffff;
    
    	return hashes;
    }
    
    static int64_t modminer_scanhash(struct thr_info *thr, struct work *work, int64_t __maybe_unused max_nonce)
    {
    	struct modminer_fpga_state *state = thr->cgpu_data;
    	struct timeval tv1, tv2;
    	int64_t hashes;
    
    	// Device is gone
    	if (thr->cgpu->usbinfo.nodev)
    		return -1;
    
    	// Don't start new work if overheated
    	if (state->overheated == true) {
    		gettimeofday(&tv1, NULL);
    
    		while (state->overheated == true) {
    			check_temperature(thr);
    
    			// Device is gone
    			if (thr->cgpu->usbinfo.nodev)
    				return -1;
    
    			if (state->overheated == true) {
    				gettimeofday(&tv2, NULL);
    
    				// give up on this work item after 30s
    				if (work_restart(thr) || tdiff(&tv2, &tv1) > 30)
    					return 0;
    
    				// Give it 1s rest then check again
    				nmsleep(1000);
    			}
    		}
    	}
    
    	if (!modminer_start_work(thr, work))
    		return -1;
    
    	hashes = modminer_process_results(thr, work);
    	if (hashes == -1)
    		return hashes;
    
    	return hashes;
    }
    
    static void modminer_hw_error(struct thr_info *thr)
    {
    	struct modminer_fpga_state *state = thr->cgpu_data;
    
    	state->hw_errors++;
    }
    
    static void modminer_fpga_shutdown(struct thr_info *thr)
    {
    	free(thr->cgpu_data);
    }
    
    static char *modminer_set_device(struct cgpu_info *modminer, char *option, char *setting, char *replybuf)
    {
    	const char *ret;
    	int val;
    
    	if (strcasecmp(option, "help") == 0) {
    		sprintf(replybuf, "clock: range %d-%d and a multiple of 2",
    					MODMINER_MIN_CLOCK, MODMINER_MAX_CLOCK);
    		return replybuf;
    	}
    
    	if (strcasecmp(option, "clock") == 0) {
    		if (!setting || !*setting) {
    			sprintf(replybuf, "missing clock setting");
    			return replybuf;
    		}
    
    		val = atoi(setting);
    		if (val < MODMINER_MIN_CLOCK || val > MODMINER_MAX_CLOCK || (val & 1) != 0) {
    			sprintf(replybuf, "invalid clock: '%s' valid range %d-%d and a multiple of 2",
    						setting, MODMINER_MIN_CLOCK, MODMINER_MAX_CLOCK);
    			return replybuf;
    		}
    
    		val -= (int)(modminer->clock);
    
    		ret = modminer_delta_clock(modminer->thr[0], val, false, true);
    		if (ret) {
    			sprintf(replybuf, "Set clock failed: %s", ret);
    			return replybuf;
    		} else
    			return NULL;
    	}
    
    	sprintf(replybuf, "Unknown option: %s", option);
    	return replybuf;
    }
    
    struct device_drv modminer_drv = {
    	.drv_id = DRIVER_MODMINER,
    	.dname = "ModMiner",
    	.name = "MMQ",
    	.drv_detect = modminer_detect,
    	.get_statline_before = get_modminer_statline_before,
    	.set_device = modminer_set_device,
    	.thread_prepare = modminer_fpga_prepare,
    	.thread_init = modminer_fpga_init,
    	.scanhash = modminer_scanhash,
    	.hw_error = modminer_hw_error,
    	.thread_shutdown = modminer_fpga_shutdown,
    };