option for icepack to skip initializing BRAM (tested for ice40hx8k)
diff --git a/icepack/icepack.cc b/icepack/icepack.cc
index 325c853..5b1745a 100644
--- a/icepack/icepack.cc
+++ b/icepack/icepack.cc
@@ -112,6 +112,7 @@
// bram[BANK][X][Y]
int bram_width, bram_height;
vector<vector<vector<bool>>> bram;
+ bool skip_bram_initialization;
// data before preamble
vector<uint8_t> initblop;
@@ -579,18 +580,20 @@
}
- debug("BRAM: Writing bank %d data.\n", bram_bank);
- write_byte(ofs, crc_value, file_offset, 0x01);
- write_byte(ofs, crc_value, file_offset, 0x03);
- for (int i = 0; i < int(bram_bits.size()); i += 8) {
- uint8_t byte = 0;
- for (int j = 0; j < 8; j++)
- byte = (byte << 1) | (bram_bits[i+j] ? 1 : 0);
- write_byte(ofs, crc_value, file_offset, byte);
- }
+ if (!this->skip_bram_initialization) {
+ debug("BRAM: Writing bank %d data.\n", bram_bank);
+ write_byte(ofs, crc_value, file_offset, 0x01);
+ write_byte(ofs, crc_value, file_offset, 0x03);
+ for (int i = 0; i < int(bram_bits.size()); i += 8) {
+ uint8_t byte = 0;
+ for (int j = 0; j < 8; j++)
+ byte = (byte << 1) | (bram_bits[i+j] ? 1 : 0);
+ write_byte(ofs, crc_value, file_offset, byte);
+ }
- write_byte(ofs, crc_value, file_offset, 0x00);
- write_byte(ofs, crc_value, file_offset, 0x00);
+ write_byte(ofs, crc_value, file_offset, 0x00);
+ write_byte(ofs, crc_value, file_offset, 0x00);
+ }
}
}
}
@@ -1348,6 +1351,9 @@
log(" -B0, -B1, -B2, -B3\n");
log(" only include the specified bank in the netpbm file\n");
log("\n");
+ log(" -n\n");
+ log(" skip initializing BRAM\n");
+ log("\n");
exit(1);
}
@@ -1372,6 +1378,7 @@
bool netpbm_bram = false;
bool netpbm_fill_tiles = false;
bool netpbm_checkerboard = false;
+ bool skip_bram_initialization = false;
int netpbm_banknum = -1;
int checkerboard_m = 1;
@@ -1406,6 +1413,8 @@
nosleep_mode = true;
} else if (arg[i] == 'v') {
log_level++;
+ } else if (arg[i] == 'n') {
+ skip_bram_initialization = true;
} else
usage();
continue;
@@ -1442,6 +1451,8 @@
usage();
FpgaConfig fpga_config;
+
+ fpga_config.skip_bram_initialization = skip_bram_initialization;
if (unpack_mode) {
fpga_config.read_bits(*isp);
