minrt: restructuring

README.md

@@ -9,7 +9,7 @@
 ## Setup
 
 ```
-meson setup --cross-file=cross/arm-none-eabi.txt --cross-file=cross/arm7tdmi.txt build
+./meson-setup.sh
 meson compile -C build
 ```
 

examples/meson.build

@@ -14,5 +14,7 @@ foreach bin : elfs
     input: bin,
     output: bin.name() + '.gba',
     command: [makerom, '@INPUT@', '@OUTPUT@'],
+    # https://github.com/mesonbuild/meson/discussions/10981#discussioncomment-4034259
+    depends: [gbafix],
     build_by_default: true)
 endforeach

meson-setup.sh

@@ -0,0 +1,2 @@
+#!/bin/sh
+meson setup --cross-file=cross/arm-none-eabi.txt --cross-file=cross/arm7tdmi.txt build

meson.build

@@ -1,5 +1,5 @@
 project('sdk-seven', 'c',
-  version: '0.1.1',
+  version: '0.2.0',
   license: 'Zlib',
   meson_version: '>=0.56.0')
 
@@ -12,8 +12,19 @@ add_project_arguments(
 add_project_link_arguments(
   '-mthumb',
   '-Wl,--gc-sections',
+  '-specs=nosys.specs',
   language: 'c')
 
+cc = meson.get_compiler('c')
+
+# Detect newlib-nano
+#
+if cc.has_argument('-specs=nano.specs')
+  add_project_link_arguments(
+    '-specs=nano.specs',
+    language: 'c')
+endif
+
 subproject('libseven')
 subproject('minrt')
 

subprojects/libseven/meson.build

@@ -27,7 +27,8 @@ libseven = static_library(
   'seven',
   sources,
   include_directories: includes + 'src',
-  c_args: ['-mthumb', '-ffunction-sections', '-fdata-sections', '-ffreestanding'])
+  c_args: ['-mthumb', '-ffunction-sections', '-fdata-sections'])
+
 
 libseven_dep = declare_dependency(
   include_directories: includes,

subprojects/minrt/meson.build

@@ -1,24 +1,25 @@
 project('minrt', 'c',
-  version: '0.1.1',
+  version: '0.2.0',
   license: 'MPL-2.0',
   default_options: ['warning_level=2', 'c_std=c99'])
 
 sources = [
-  'src/crt0.s',
-  'src/ram.c',
+  'src/gba/rom_header.s',
+  'src/gba/crt0.s',
+  'src/gba/ram.c',
 ]
 
 includes = ['include']
 
 lib = meson.project_source_root() / 'lib'
 
-link_args = ['-specs=' + lib / 'nocrt0.specs', '-L' + lib]
+link_args = ['-specs=' + lib / 'nocrt0.specs', '-L' + lib / 'ldscripts']
 
 minrt = static_library(
   'minrt',
   sources,
-  include_directories: includes + 'src',
-  c_args: ['-mthumb', '-ffunction-sections', '-fdata-sections', '-ffreestanding'])
+  include_directories: includes + 'src' + 'src/gba',
+  c_args: ['-mthumb', '-ffunction-sections', '-fdata-sections'])
 
 minrt_dep = declare_dependency(
   include_directories: includes,

subprojects/minrt/src/crt0.s → subprojects/minrt/src/gba/crt0.s

@@ -7,34 +7,14 @@
 .syntax         unified
 .cpu            arm7tdmi
 
-.section        .rom_header,"ax",%progbits
-.align 2
-.arm
 _start:
-    b           entrypoint      @ ROM entry point
-    .include    "header.s"
-    b           entrypoint      @ Multiboot entry point
-_boot_type:
-    .zero       1               @ Boot type
-_boot_client:
-    .zero       1               @ Client number
-    .zero       26              @ Reserved
-    b           entrypoint      @ JOY Bus entry point
-
-.align 2
-.arm
-entrypoint:
     add         r0, pc, #1
     bx          r0
 .thumb
     @ IRQs off
     ldr         r3, =REG_IME
     strh        r3, [r3]
 
-    ldr         r3, =REG_WRAMCNT
-    ldr         r2, =__wramcnt
-    str         r2, [r3]
-
     ldr         r3, =REG_DMA3
 
     @ .iwram section
@@ -151,12 +131,14 @@ fini_skip:
 
 pool: .pool
 
+@ HACK: Reference a symbol from the header so it doesn't get dropped during link
+.equiv          KEEP_HEADER,    __boot_type
 .equiv          REG_DMA3,       0x040000D4
 .equiv          REG_IME,        0x04000208
 .equiv          REG_WRAMCNT,    0x04000800
 .equiv          SVC_CPUSET,     11
 
-.global         _start, _exit, _boot_type, _boot_client
+.global         _start, _exit
 .weak           _exit
 
 @ vim: ft=armv4 et sta sw=4 sts=8

subprojects/minrt/src/gba/rom_header.s

@@ -0,0 +1,24 @@
+@
+@ This Source Code Form is subject to the terms of the Mozilla Public
+@ License, v. 2.0. If a copy of the MPL was not distributed with this
+@ file, You can obtain one at https://mozilla.org/MPL/2.0/.
+@
+
+.syntax         unified
+.cpu            arm7tdmi
+
+.section        .rom_header,"ax",%progbits
+
+    b           _start                  @ ROM entry point
+    .include    "rom_header_data.s"     @ ROM header information
+    b           _start                  @ Multiboot entry point
+__boot_type:
+    .zero       1                       @ Link transfer boot type
+__boot_client:
+    .zero       1                       @ Multiplayer player number
+    .zero       26                      @ Reserved
+    b           _start                  @ JOY Bus entry point
+
+.global         __boot_type, __boot_client
+
+@ vim: ft=armv4 et sta sw=4 sts=8

subprojects/minrt/src/header.s → subprojects/minrt/src/gba/rom_header_data.s

@@ -1,4 +1,4 @@
-@ NINTENDO LOGO DATA
+@ Nintendo Logo Data
 .byte   0x24, 0xFF, 0xAE, 0x51, 0x69, 0x9A, 0xA2, 0x21
 .byte   0x3D, 0x84, 0x82, 0x0A, 0x84, 0xE4, 0x09, 0xAD
 .byte   0x11, 0x24, 0x8B, 0x98, 0xC0, 0x81, 0x7F, 0x21
@@ -19,7 +19,7 @@
 .byte   0x65, 0xC0, 0x7C, 0x63, 0x87, 0xF0, 0x3C, 0xAF
 .byte   0xD6, 0x25, 0xE4, 0x8B, 0x38, 0x0A, 0xAC, 0x72
 .byte   0x21, 0xD4, 0xF8, 0x07
-@ CHECKSUM AREA BEGIN
+@ Checksum Area Start
 .zero   12              @ Game title
 .zero   4               @ Game code
 .zero   2               @ Maker code
@@ -28,7 +28,7 @@
 .zero   1               @ Device type
 .zero   7               @ Reserved
 .zero   1               @ Game version
-@ CHECKSUM AREA END
+@ Checksum Area End
 .byte   0x51            @ Checksum
 .zero   2               @ Reserved