bare_metal support, Winbond flash support, two-stage BL update support

.gitignore

@@ -8,3 +8,6 @@ synlog.tcl
 gerbers/
 build/
 *.pyc
+next_serial.txt
+_boardmeta_prod.json
+bootloader_copy.bin

boards/bare_metal/Makefile

@@ -0,0 +1,156 @@
+# bare_metal USB bootloader - Makefile
+# based on TinyFPGA BX bootloader build flow
+
+PROJ     = bootloader
+PIN_DEF  = pins.pcf
+DEVICE   = up5k
+PKG      = sg48
+
+# Path to TinyFPGA bootloader common Verilog
+COMMON   = ../../common
+
+# All source files
+SRC      = $(PROJ).v $(wildcard $(COMMON)/*.v)
+
+# Support up to three user bitstreams (slots 1..3). By default use the
+# placeholder copy of the bootloader so all slots contain something.
+USER_BITSTREAM_1 ?= bootloader_copy.bin
+USER_BITSTREAM_2 ?= bootloader_copy.bin
+USER_BITSTREAM_3 ?= bootloader_copy.bin
+
+# flash memory map
+
+# 0x000_0000 - 0x000_009f =160b, multiboot header, slot table
+# 0x000_00a0 - 0x001_efff ~124kB, slot 0, bare_metal_bootloader
+# 0x001_f000 - 0x001_ffff =4kB, bootmetadata
+# 0x002_0000 - 0x003_ffff =128kB, slot 1, user bitstream, hackerstacker_demo by default
+# 0x004_0000 - 0x005_ffff =128kB, slot 2, transputers anyone?
+# 0x006_0000 - 0x007_ffff ~128kB, slot 3, hooray for transputers
+# 0x008_0000 - 0x100_0000 user data, images, fonts, text, sounds, etc
+
+# UP5K bitstream is always ~104 KB, so we need 2^17 = 128 KB alignment
+ALIGN    = 17
+
+all: $(PROJ).rpt multiboot.bin
+
+$(PROJ).json: $(SRC)
+	yosys -p 'synth_ice40 -top $(PROJ) -json $@' $(SRC)
+
+$(PROJ).asc: $(PIN_DEF) $(PROJ).json
+	nextpnr-ice40 --$(DEVICE) --package $(PKG) --pcf $(PIN_DEF) --json $(PROJ).json --asc $@
+
+$(PROJ).bin: $(PROJ).asc
+	icepack $< $@
+
+# Metadata offset within slot 0 (must be within the 128KB slot, after bitstream)
+META_ADDR = 0x1F000
+
+# Build multiboot image:
+#   -p0  = power-on image is slot 0 (bootloader)
+#   -a17 = each image aligned at 128 KB boundary
+# For now, slot 1 is a copy of the bootloader (placeholder).
+# Replace bootloader_copy.bin with your user design when ready.
+# After icemulti, inject minified bootmeta.json at META_ADDR.
+multiboot.bin: $(PROJ).bin bootmeta.json
+	cp $(PROJ).bin bootloader_copy.bin
+	# Build a multiboot image with the bootloader (slot 0) followed by up to
+	# three user bitstreams (slots 1..3). Defaults point to the placeholder
+	# copy so the image is valid even if you don't provide real user bitfiles.
+	icemulti -v -o $@ -a$(ALIGN) -p0 bootloader.bin $(USER_BITSTREAM_1) $(USER_BITSTREAM_2) $(USER_BITSTREAM_3)
+	python3 -c "\
+import json; \
+d = json.load(open('bootmeta.json')); \
+blob = json.dumps(d, separators=(',',':')).encode(); \
+assert len(blob) <= 4096, f'bootmeta too large: {len(blob)} bytes (max 4096)'; \
+f = open('$@', 'r+b'); \
+f.seek($(META_ADDR)); \
+f.write(b'\\xff' * 4096); \
+f.seek($(META_ADDR)); \
+f.write(blob); \
+f.close(); \
+print(f'  Injected {len(blob)} bytes of bootmeta at $(META_ADDR)')"
+
+$(PROJ).rpt: $(PROJ).asc
+	icetime -d $(DEVICE) -mtr $@ $<
+
+# erase SPI flash (required before 'make prog' on non-empty flash)
+# leaving manually as it's time-consuming
+erase:
+	ch341prog -v -e
+
+# Flash multiboot image via CH341A clip programmer
+prog: multiboot.bin
+	ch341prog -v -w multiboot.bin
+
+# stage_two.bin: slot 0 with valid multiboot header, for OTA update.
+# Written to address 0x0 by tinyprog during stage two of bootloader update.
+# Uses icemulti with TWO images (so the header has a valid slot 1 entry),
+# injects bootmeta, then truncates to 0x20000 (slot 0 boundary).
+stage_two.bin: $(PROJ).bin bootmeta.json
+	cp $(PROJ).bin bootloader_copy.bin
+	icemulti -v -o $@ -a$(ALIGN) -p0 bootloader.bin bootloader_copy.bin
+	python3 -c "\
+import json; \
+d = json.load(open('bootmeta.json')); \
+blob = json.dumps(d, separators=(',',':')).encode(); \
+assert len(blob) <= 4096, f'bootmeta too large: {len(blob)} bytes (max 4096)'; \
+f = open('$@', 'r+b'); \
+f.seek($(META_ADDR)); \
+f.write(b'\\xff' * 4096); \
+f.seek($(META_ADDR)); \
+f.write(blob); \
+f.close(); \
+# truncate to slot 0 boundary - keeps header + bootloader + bootmeta \
+data = open('$@','rb').read()[:0x20000]; \
+# strip trailing 0xff, round up to 256B \
+end = len(data); \
+while end > 0 and data[end-1] == 0xff: end -= 1; \
+end = (end + 255) & ~255; \
+open('$@','wb').write(data[:end]); \
+print(f'  stage_two.bin: {end} bytes (bootmeta at $(META_ADDR))')"
+
+# User address in flash - must match icemulti -a$(ALIGN)
+USER_ADDR = 0x20000
+
+# Build a multiboot image with a real user design
+# Usage: make multiboot-user USER_BIN=path/to/user.bin
+multiboot-user: $(PROJ).bin
+	icemulti -v -o multiboot.bin -a$(ALIGN) -p0 $(PROJ).bin $(USER_BIN)
+
+# Just boot to user image (no programming)
+boot:
+	tinyprog --boot
+
+clean:
+	rm -f $(PROJ).json $(PROJ).asc $(PROJ).rpt $(PROJ).bin
+	rm -f bootloader_copy.bin multiboot.bin stage_two.bin
+
+# production: provision one board via CH341
+# reads serial from next_serial.txt, generates a UUID, writes boardmeta
+# to security register page 1, flashes multiboot.bin to address 0.
+CH341PROG ?= ch341prog
+SECREG_PAGE = 1
+
+produce_one_board: multiboot.bin
+	@echo "=== Producing board ==="
+	@SERIAL=$$(cat next_serial.txt) && \
+	UUID=$$(python3 -c "import uuid; print(uuid.uuid4())") && \
+	echo "  Serial: $$SERIAL" && \
+	echo "  UUID:   $$UUID" && \
+	python3 -c "\
+import json, sys; \
+d = json.load(open('boardmeta.json')); \
+d['boardmeta']['serial'] = int(sys.argv[1]); \
+d['boardmeta']['uuid'] = sys.argv[2]; \
+open('_boardmeta_prod.json','w').write(json.dumps(d, separators=(',',':')))" \
+	    "$$SERIAL" "$$UUID" && \
+	echo "  Minified: $$(wc -c < _boardmeta_prod.json) bytes (max 256)" && \
+	test $$(wc -c < _boardmeta_prod.json) -le 256 || { echo "ERROR: boardmeta > 256 bytes!"; rm -f _boardmeta_prod.json; exit 1; } && \
+	$(CH341PROG) -W $(SECREG_PAGE) _boardmeta_prod.json && \
+	$(CH341PROG) -L $(SECREG_PAGE) && \
+	$(CH341PROG) -w multiboot.bin && \
+	echo $$(($$SERIAL + 1)) > next_serial.txt && \
+	echo "=== Board $$SERIAL done. Next serial: $$(cat next_serial.txt) ===" && \
+	rm -f _boardmeta_prod.json
+
+.PHONY: all prog multiboot-user flash-user boot clean erase produce_one_board

boards/bare_metal/boardmeta.json

@@ -0,0 +1,10 @@
+{
+ "boardmeta":{
+  "name": "bare_metal",
+   "fpga": "ice40up5k-sg48",
+   "hver": "0.1",
+   "serial": 12345,
+   "uuid": "00000000-1111-2222-3333-444444444444",
+   "url": "https://wenzellabs.de/bare_metal"
+ }
+}