Merge pull request #2748 from n-hutton/deterministic_bitfile_builds2

force bitfiles to be identical for same source code

fpga/Makefile

@@ -44,6 +44,9 @@ XST_OPTS_AREA += -opt_level 2
 XST_OPTS_AREA += -fsm_style bram
 XST_OPTS_AREA += -fsm_encoding compact
 
+# par specific option (set determistic seed)
+PAR_OPTIONS = -t 1
+
 # Types of selective module compilation:
 # WITH_LF  Enables selection of LF modules (and disables all HF)
 
@@ -179,12 +182,13 @@ work:
 %.ncd: %_map.ncd
 	$(Q)$(RM) $@
 	$(info [-] PAR $@)
-	$(Q)$(XILINX_TOOLS_PREFIX)par $(VERBOSITY) -w $< $@
+	$(Q)$(XILINX_TOOLS_PREFIX)par $(PAR_OPTIONS) $(VERBOSITY) -w $< $@
 
 %.bit: %.ncd
 	$(Q)$(RM) $@ $*.drc $*.rbt
 	$(info [=] BITGEN $@)
 	$(Q)$(XILINX_TOOLS_PREFIX)bitgen $(VERBOSITY) -w $* $@
+	python3 ../strip_date_time_from_binary.py $@ || true
 	$(Q)$(CP) $@ ..
 
 # Build all targets

fpga/strip_date_time_from_binary.py

@@ -0,0 +1,51 @@
+import sys
+
+# File to take a .bit file generated by xilinx webpack ISE
+# and replace the date and time embedded within with 'F'.
+# The header of the bitfile is seperated by ascii markers
+# 'a', 'b', 'c', 'd' etc.
+# see fpga_compress.c for comparison
+
+def parse_and_split_file(filename):
+    split_chars = ['a', 'b', 'c', 'd']  # Characters to split on
+    extracted_data = [] # for debug
+
+    print("Overwriting date and time in bitfile {}".format(filename))
+
+    with open(filename, 'rb') as f:  # Read as binary to handle non-text files
+        data = f.read(100)  # Read first 100 bytes which should contain all information
+
+    decoded_data = bytearray(data)
+
+    for i in range(len(decoded_data) - 3):
+        # subsequent two bytes after marker are null and the length
+        next_byte   = decoded_data[i+1]
+        data_length = decoded_data[i+2] - 1 # Don't overwrite terminating char
+
+        if decoded_data[i] == ord(split_chars[0]) and next_byte == 0x0:
+            start = i+3
+            extracted_data.append(decoded_data[start:start+data_length])
+
+            # time, date
+            if split_chars[0] == 'c' or split_chars[0] == 'd':
+                decoded_data[start:start+data_length] = bytes('F', encoding='ascii') * data_length
+
+            split_chars.pop(0)
+
+            if not split_chars:
+                break
+
+    print("Extracted data from bitfile: {}".format(extracted_data))
+
+    with open(filename, 'r+b') as f:  # Write back modified bytes
+        f.seek(0)
+        f.write(decoded_data.ljust(100, b' '))
+    print("writing complete")
+
+if __name__ == "__main__":
+    if len(sys.argv) < 2:
+        print("Usage: python script.py <filename>")
+        sys.exit(1)
+
+    filename = sys.argv[1]
+    parse_and_split_file(filename)

tools/fpga_compress/fpga_compress.c

@@ -18,9 +18,13 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include <inttypes.h>
+#include <sys/stat.h>
+#include "time.h"
 #include "fpga.h"
 #include "lz4hc.h"
 
+int fileno(FILE *);
+
 #ifndef MIN
 #define MIN(a,b) ((a) < (b) ? (a) : (b))
 #endif
@@ -354,6 +358,8 @@ static int FpgaGatherVersion(FILE *infile, char *infile_name, char *dst, int len
     for (uint16_t i = 0; i < FPGA_BITSTREAM_FIXED_HEADER_SIZE; i++) {
         if (fgetc(infile) != bitparse_fixed_header[i]) {
             fprintf(stderr, "Invalid FPGA file. Aborting...\n\n");
+            fprintf(stderr, "File: %s\n", infile_name);
+
             return (EXIT_FAILURE);
         }
     }
@@ -380,30 +386,22 @@ static int FpgaGatherVersion(FILE *infile, char *infile_name, char *dst, int len
         strncat(dst, tempstr, len - strlen(dst) - 1);
     }
 
-    strncat(dst, " ", len - strlen(dst) - 1);
+    // Get file statistics to extract date and time via file timestamp
-    if (bitparse_find_section(infile, 'c', &fpga_info_len)) {
+    int fd = fileno(infile);
-        for (uint32_t i = 0; i < fpga_info_len; i++) {
+    struct stat fileStat;
-            char c = (char)fgetc(infile);
+
-            if (i < sizeof(tempstr)) {
+    if (fstat(fd, &fileStat) == 0) {
-                if (c == '/') c = '-';
+        struct tm *modTime = localtime(&fileStat.st_mtime);
-                if (c == ' ') c = '0';
+
-                tempstr[i] = c;
+
-            }
+        char timeBuf[64];
-        }
+        snprintf(timeBuf, sizeof(timeBuf), " %02d-%02d-%04d %02d:%02d:%02d",
-        strncat(dst, tempstr, len - strlen(dst) - 1);
+                 modTime->tm_mday, modTime->tm_mon + 1, modTime->tm_year + 1900,
+                 modTime->tm_hour, modTime->tm_min, modTime->tm_sec);
+
+        strncat(dst, timeBuf, len - strlen(dst) - 1);
     }
 
-    if (bitparse_find_section(infile, 'd', &fpga_info_len)) {
-        strncat(dst, " ", len - strlen(dst) - 1);
-        for (uint32_t i = 0; i < fpga_info_len; i++) {
-            char c = (char)fgetc(infile);
-            if (i < sizeof(tempstr)) {
-                if (c == ' ') c = '0';
-                tempstr[i] = c;
-            }
-        }
-        strncat(dst, tempstr, len - strlen(dst) - 1);
-    }
     return 0;
 }