Merge branch 'filesystem': FAT filesystem on flash with require support

Author: harukasan

CLAUDE.md

@@ -24,7 +24,10 @@ Design documents and implementation notes are in `doc/`:
 - [doc/psram.md](doc/psram.md) — PSRAM driver (APS6404L, QMI CS1 initialization, XIP mapping)
 - [doc/dvi.md](doc/dvi.md) — DVI output (HSTX, DMA, text/pixel modes, stability analysis)
 - [doc/dvi/batch-rendering.md](doc/dvi/batch-rendering.md) — Batch scanline rendering (N=4, line buffers, descriptor layout)
+- [doc/dvi/text-mode-rendering.md](doc/dvi/text-mode-rendering.md) — Text mode rendering (VRAM, font cache, scanline renderer)
+- [doc/dvi/stability.md](doc/dvi/stability.md) — DVI stability analysis (bus contention, flash write safety, diagnostics)
 - [doc/usb-host-keyboard.md](doc/usb-host-keyboard.md) — USB host keyboard (PIO-USB, HID, Ruby/C API)
+- [doc/filesystem.md](doc/filesystem.md) — FAT filesystem on flash (FatFs, VFS, flash write safety)
 
 ## Documentation style
 

CMakeLists.txt

@@ -118,6 +118,9 @@ add_executable(harucom_os
     src/main.c
     src/hal.c
     src/psram.c
+    src/flash_disk.c
+    src/platform.c
+    src/env.c
     ${PICORUBY_ROOT}/mrbgems/picoruby-gpio/ports/rp2040/gpio.c
     mrbgems/picoruby-usb-host/ports/rp2350/usb_host.c
 )
@@ -144,6 +147,7 @@ target_compile_definitions(harucom_os PRIVATE
     MRB_TIMESLICE_TICK_COUNT=10
     MRB_USE_TASK_SCHEDULER=1
     NO_CLOCK_GETTIME=1
+    USE_FAT_FLASH_DISK=1
     NDEBUG=1
     BOARD_TUH_RHPORT=1
 )
@@ -152,6 +156,7 @@ target_compile_options(harucom_os PRIVATE -fshort-enums)
 
 target_include_directories(harucom_os PRIVATE
     ${CMAKE_CURRENT_LIST_DIR}/src
+    ${CMAKE_CURRENT_LIST_DIR}/include
     ${PICORUBY_ROOT}/include
     ${PICORUBY_ROOT}/build/${PICORUBY_BUILD_CONFIG}/include
     ${PICORUBY_ROOT}/mrbgems/picoruby-mruby/lib/mruby/include
@@ -161,6 +166,12 @@ target_include_directories(harucom_os PRIVATE
     ${PICORUBY_ROOT}/mrbgems/picoruby-gpio/include
     ${PICORUBY_ROOT}/mrbgems/picoruby-mruby/lib/mruby/mrbgems/mruby-task/include
     ${PICORUBY_ROOT}/mrbgems/picoruby-machine/include
+    ${PICORUBY_ROOT}/mrbgems/picoruby-require/include
+    ${PICORUBY_ROOT}/mrbgems/picoruby-env/include
+    ${PICORUBY_ROOT}/mrbgems/picoruby-time/include
+    ${PICORUBY_ROOT}/mrbgems/picoruby-filesystem-fat/include
+    ${PICORUBY_ROOT}/mrbgems/picoruby-filesystem-fat/lib/ff14b/source
+    ${PICORUBY_ROOT}/mrbgems/picoruby-filesystem-fat/src/hal
     ${PICORUBY_ROOT}/build/${PICORUBY_BUILD_CONFIG}/mrbgems
     ${CMAKE_CURRENT_LIST_DIR}/mrbgems/picoruby-usb-host/include
 )

build_config/harucom-os-pico2.rb

@@ -12,6 +12,7 @@
   conf.cc.defines << "MRB_USE_CUSTOM_RO_DATA_P"
   conf.cc.defines << "MRB_LINK_TIME_RO_DATA_P"
   conf.cc.defines << "NO_CLOCK_GETTIME=1"
+  conf.cc.defines << "USE_FAT_FLASH_DISK"
 
   conf.cc.command = "arm-none-eabi-gcc"
   conf.linker.command = "arm-none-eabi-ld"
@@ -39,7 +40,11 @@
   conf.microruby
 
   conf.gembox "minimum"
+  conf.gem gemdir: "#{MRUBY_ROOT}/mrbgems/picoruby-mruby/lib/mruby/mrbgems/mruby-string-ext"
   conf.gem core: 'picoruby-gpio'
+  conf.gem core: 'picoruby-require'
+  conf.gem core: 'picoruby-vfs'
+  conf.gem core: 'picoruby-filesystem-fat'
   conf.gem File.expand_path('../../mrbgems/picoruby-dvi', __FILE__)
   conf.gem File.expand_path('../../mrbgems/picoruby-usb-host', __FILE__)
 end