thodg/cgminer

diff --git a/FPGA-README b/FPGA-README
index 0c4da8a..6526031 100644
--- a/FPGA-README
+++ b/FPGA-README
@@ -13,6 +13,11 @@ a cost of 1% in overall hashrate so this feature is disabled by default. It
 is only recommended you enable this if you are mining with a minirig on
 p2pool.
 
+C source is included for a bitforce firmware flash utility on Linux only:
+ bitforce-firmware-flash.c
+Using this, you can change the bitstream firmware on bitforce singles.
+It is untested with other devices. Use at your own risk!
+
 
 Icarus
 
diff --git a/bitforce-firmware-flash.c b/bitforce-firmware-flash.c
new file mode 100644
index 0000000..fff27e4
--- /dev/null
+++ b/bitforce-firmware-flash.c
@@ -0,0 +1,106 @@
+/*
+ * 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.
+ */
+
+#define _BSD_SOURCE
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <libgen.h>
+#include <arpa/inet.h>
+
+#define BFL_FILE_MAGIC   "BFLDATA"
+#define BFL_UPLOAD_MAGIC "NGH-STREAM"
+
+#define myassert(expr, n, ...)  do {  \
+	if (!(expr))  \
+	{  \
+		fprintf(stderr, __VA_ARGS__);  \
+		return n;  \
+	}  \
+} while(0)
+
+#define ERRRESP(buf)  buf, (buf[strlen(buf)-1] == '\n' ? "" : "\n")
+
+#define WAITFOROK(n, msg)  do {  \
+	myassert(fgets(buf, sizeof(buf), BFL), n, "Error reading response from " msg "\n");  \
+	myassert(!strcmp(buf, "OK\n"), n, "Invalid response from " msg ": %s%s", ERRRESP(buf));  \
+} while(0)
+
+int
+main(int argc, char**argv) {
+	myassert(argc == 3, 1, "Usage: %s <serialdev> <firmware.bfl>\n", argv[0]);
+	setbuf(stdout, NULL);
+	
+	// Check filename
+	char *FWname = basename(strdup(argv[2]));
+	size_t FWnameLen = strlen(FWname);
+	myassert(FWnameLen <= 255, 0x0f, "Firmware filename '%s' is too long\n", FWname);
+	uint8_t n8 = FWnameLen;
+	
+	// Open and check firmware file
+	FILE *FW = fopen(argv[2], "r");
+	myassert(FW, 0x10, "Failed to open '%s' for reading\n", argv[2]);
+	char buf[0x20];
+	myassert(1 == fread(buf, 7, 1, FW), 0x10, "Failed to read from '%s'\n", argv[2]);
+	myassert(!memcmp(buf, BFL_FILE_MAGIC, sizeof(BFL_FILE_MAGIC)-1), 0x11, "'%s' doesn't look like a BFL firmware\n", argv[2]);
+	myassert(!fseek(FW, 0, SEEK_END), 0x12, "Failed to find end of '%s'\n", argv[2]);
+	long FWlen = ftell(FW);
+	myassert(FWlen > 0, 0x12, "Couldn't get size of '%s'\n", argv[2]);
+	myassert(!fseek(FW, 7, SEEK_SET), 0x12, "Failed to rewind firmware file after getting size\n");
+	FWlen -= 7;
+	printf("Firmware file looks OK :)\n");
+	
+	// Open device
+	FILE *BFL = fopen(argv[1], "r+");
+	myassert(BFL, 0x20, "Failed to open '%s' for read/write\n", argv[1]);
+	myassert(!setvbuf(BFL, NULL, _IOFBF, 1032), 0x21, "Failed to setup buffer for device");
+	
+	// ZAX: Start firmware upload
+	printf("Starting firmware upload... ");
+	myassert(1 == fwrite("ZAX", 3, 1, BFL), 0x22, "Failed to issue ZAX command\n");
+	WAITFOROK(0x22, "ZAX");
+	
+	// Firmware upload header
+	myassert(1 == fwrite(BFL_UPLOAD_MAGIC, sizeof(BFL_UPLOAD_MAGIC)-1, 1, BFL), 0x23, "Failed to send firmware upload header (magic)\n");
+	uint32_t n32 = htonl(FWlen - FWlen / 6);
+	myassert(1 == fwrite(&n32, sizeof(n32), 1, BFL), 0x23, "Failed to send firmware upload header (size)\n");
+	myassert(1 == fwrite("\0\0", 2        , 1, BFL), 0x23, "Failed to send firmware upload header (padding 1)\n");
+	myassert(1 == fwrite(&n8, sizeof(n8)  , 1, BFL), 0x23, "Failed to send firmware upload header (filename length)\n");
+	myassert(1 == fwrite(FWname, n8       , 1, BFL), 0x23, "Failed to send firmware upload header (filename)\n");
+	myassert(1 == fwrite("\0>>>>>>>>", 9  , 1, BFL), 0x23, "Failed to send firmware upload header (padding 2)\n");
+	WAITFOROK(0x23, "firmware upload header");
+	printf("OK, sending...\n");
+	
+	// Actual firmware upload
+	for (long i = 0, j = 0; i < FWlen; ++i)
+	{
+		myassert(1 == fread(&n8, sizeof(n8), 1, FW), 0x30, "Error reading data from firmware file\n");
+		if (5 == i % 6)
+			continue;
+		n8 ^= 0x2f;
+		myassert(1 == fwrite(&n8, sizeof(n8), 1, BFL), 0x31, "Error sending data to device\n");
+		if (!(++j % 0x400))
+		{
+			myassert(1 == fwrite(">>>>>>>>", 8, 1, BFL), 0x32, "Error sending block-finish to device\n");
+			printf("\r%5.2f%% complete", (double)i * 100. / (double)FWlen);
+			WAITFOROK(0x32, "block-finish");
+		}
+	}
+	printf("\r100%% complete :)\n");
+	myassert(1 == fwrite(">>>>>>>>", 8, 1, BFL), 0x3f, "Error sending upload-finished to device\n");
+	myassert(fgets(buf, sizeof(buf), BFL), 0x3f, "Error reading response from upload-finished\n");  \
+	myassert(!strcmp(buf, "DONE\n"), 0x3f, "Invalid response from upload-finished: %s%s", ERRRESP(buf));  \
+	
+	// ZBX: Finish programming
+	printf("Waiting for device... ");
+	myassert(1 == fwrite("ZBX", 3, 1, BFL), 0x40, "Failed to issue ZBX command\n");
+	WAITFOROK(0x40, "ZBX");
+	printf("ALL DONE!\n");
+}