From b129d5c5f5b8764bb0dbd9ee7f86ea7287ca9390 Mon Sep 17 00:00:00 2001
From: Philippe Sauter <phsauter@iis.ee.ethz.ch>
Date: Fri, 27 Sep 2024 12:16:07 +0200
Subject: [PATCH] sw: change hex from words to bytes

objcopy with --verilog-data-width produces inconsistent
byte ordering between different installs -> useless
---
 Makefile           |  2 ++
 rtl/tb_croc_soc.sv | 40 ++++++++++++++++++++++++++++------------
 sw/Makefile        |  2 +-
 3 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/Makefile b/Makefile
index d38ed80..eb1fab7 100644
--- a/Makefile
+++ b/Makefile
@@ -49,6 +49,8 @@ $(SW):
 ## Build the helloworld software
 software: $(SW)
 
+sw: $(SW)
+
 .PHONY: software
 
 ##################
diff --git a/rtl/tb_croc_soc.sv b/rtl/tb_croc_soc.sv
index a08b731..3d331ab 100644
--- a/rtl/tb_croc_soc.sv
+++ b/rtl/tb_croc_soc.sv
@@ -178,6 +178,8 @@ module tb_croc_soc #(
         string line;
         bit [31:0] addr;
         bit [31:0] data;
+        bit [7:0] byte_data;
+        int byte_count;
 
         file = $fopen(filename, "r");
         if (file == 0) begin
@@ -189,27 +191,41 @@ module tb_croc_soc #(
         // line by line
         while (!$feof(file)) begin
             if ($fgets(line, file) == 0) begin
-                break;
+                break; // End of file
             end
-            // lines starting with @ are addresses
+            
+            // '@' indicates address
             if (line[0] == "@") begin
                 status = $sscanf(line, "@%h", addr);
                 if (status != 1) begin
                     $fatal(1, "Error: Incorrect address line format in file %s", filename);
                 end
-            end else begin
-                // otherwise it contains space separated 32bit data blocks
-                while (line.len() > 0) begin
-                    status = $sscanf(line, "%h", data); // extract one 32bit block
-                    if (status != 1) begin
-                        break; // No more data to read on this line
-                    end
+                continue;
+            end
+
+            byte_count = 0;
+            data = 32'h0;
+
+            // Loop through the line to read bytes
+            while (line.len() > 0) begin
+                status = $sscanf(line, "%h", byte_data); // Extract one byte
+                if (status != 1) begin
+                    break; // No more data to read on this line
+                end
+
+                // Shift in the byte to the correct position in the data word
+                data = {data[23:0], byte_data}; // Combine bytes into a 32-bit word
+                byte_count++;
 
+                // remove the byte from the line (2 numbers + 1 space)
+                line = line.substr(3, line.len()-1);
+
+                // write a complete word via jtag
+                if (byte_count == 4) begin
                     jtag_write_reg32(addr, data, 1'b0);
                     addr += 4;
-
-                    // remove the processed 32-bit value from the line
-                    line = line.substr(8 + 1, line.len()-1);
+                    data = 32'h0;
+                    byte_count = 0;
                 end
             end
         end
diff --git a/sw/Makefile b/sw/Makefile
index a743214..ae35c50 100644
--- a/sw/Makefile
+++ b/sw/Makefile
@@ -55,7 +55,7 @@ $(BINDIR)/%.dump: $(BINDIR)/%.elf
 	$(RISCV_OBJDUMP) -D -s $< >$@
 
 $(BINDIR)/%.hex: $(BINDIR)/%.elf
-	$(RISCV_OBJCOPY) --reverse-bytes 4 -O verilog --verilog-data-width 4 $< $@
+	$(RISCV_OBJCOPY) -O verilog $< $@
 
 # keep dumps