diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/boot.asm | 15 | ||||
| -rw-r--r-- | src/dmesg.asm | 311 | ||||
| -rw-r--r-- | src/fs.asm | 2 | ||||
| -rw-r--r-- | src/kdata.asm | 3 | ||||
| -rw-r--r-- | src/programs.asm | 1 |
5 files changed, 330 insertions, 2 deletions
diff --git a/src/boot.asm b/src/boot.asm index c29267d..c2d461a 100644 --- a/src/boot.asm +++ b/src/boot.asm @@ -41,12 +41,19 @@ SECTION "kinit", ROM0 KernelInit: di ld sp, KSTACK_TOP + push af ; boot ROM hands the console model in A/B - + push bc ; park it on the (uncleared) stack for dmesg ; enable cart RAM (MBC5) ld a, $0A ld [MBC5_RAM_ENABLE], a call ClearKernelRAM + pop bc + pop af + ld [wBootA], a + ld a, b + ld [wBootB], a call CopyHramCode ; move context-switch trampoline into HRAM call ProcInit ; wipe process table ; point wCurProc at the (zeroed) kernel PCB so disk I/O during boot restores @@ -56,11 +63,15 @@ KernelInit: ld a, HIGH(wKernelPCB) ld [wCurProc+1], a call pipe_init ; mark all pipes free + call term_init ; LCD console first, so the boot spew is visible + call boot_banner ; dmesg: kernel/console/cart/mem/proc lines call net_init ; clear the socket table, set our IP (10.0.0.2) + call boot_net call fs_init ; mount the disk (format on first boot; persists) - call term_init ; set up the LCD text terminal + call boot_fs call osk_init ; build the on-screen keyboard (window layer) - ; terminal starts blank; shell output flows in via KPutc + call boot_tty + call boot_init ; "init: spawning pid 1" ; --- spawn the init task (pid 1); it fork()s the rest --- ld hl, TaskInit diff --git a/src/dmesg.asm b/src/dmesg.asm new file mode 100644 index 0000000..5d991b0 --- /dev/null +++ b/src/dmesg.asm @@ -0,0 +1,311 @@ +; ============================================================================= +; dmesg.asm - kernel boot spew: everything the kernel knows implicitly before +; init spawns, printed dmesg-style on the LCD console (and mirrored over the +; link port, so a gbhub logs the whole boot). +; +; The info costs nothing to know: +; - the boot ROM hands the console model in A/B at entry (saved to wBootA/B) +; - the cartridge describes itself in its own header ($0147-$0149) +; - the CGB memory map is a constant of the hardware +; - subsystem shapes (proc slots, sockets, program table) are link-time facts +; - fs_init just mounted (or formatted) the disk and left the block bitmap +; in fs_bmbuf - counting free blocks is a 16-byte popcount +; ============================================================================= +INCLUDE "include/gbos.inc" + +SECTION "dmesg", ROM0 + +; ----------------------------------------------------------------------------- +; kernel console output (boot-time: no process context, so KPutc is unusable) +; ----------------------------------------------------------------------------- +; kputc(A = char) - LCD terminal + serial mirror. Preserves BC/DE/HL. +kputc:: + push bc + push de + push hl + ld b, a + ld [rSB], a ; mirror to the link (gbhub console log) + ld a, $81 + ld [rSC], a + ld a, b + call term_putc + pop hl + pop de + pop bc + ret + +; kputs(HL = NUL-terminated string). Clobbers A, HL. +kputs:: +.l + ld a, [hl+] + or a + ret z + call kputc + jr .l + +; kputhex(A = byte) - two uppercase hex digits. Clobbers A. +kputhex:: + push af + swap a + call .nib + pop af +.nib + and $0F + add "0" + cp "9" + 1 + jr c, .put + add "A" - "9" - 1 +.put + jp kputc + +; kputdec(A = 0..255) - decimal, no leading zeros. Clobbers A, BC, DE. +kputdec:: + ld c, 0 ; "printed a digit yet" flag + ld b, 100 + call .digit + ld b, 10 + call .digit + add "0" + jp kputc ; ones digit always prints +.digit ; A/B -> A = remainder; prints quotient digit + ld e, 0 +.sub + cp b + jr c, .rem + sub b + inc e + jr .sub +.rem + ld d, a + ld a, e + or c + jr z, .skip ; leading zero + ld a, e + add "0" + call kputc + ld c, 1 +.skip + ld a, d + ret + +; ----------------------------------------------------------------------------- +; boot_banner - kernel line + console model + cart header + memory map + proc +; shape. Called right after term_init. +; ----------------------------------------------------------------------------- +boot_banner:: + ld hl, .s_kernel + call kputs + + ; console model: boot ROM leaves A=$11 (CGB/AGB, B bit0 = AGB), $01 (DMG), + ; $FF (MGB/pocket) + ld hl, .s_console + call kputs + ld a, [wBootA] + cp $11 + jr nz, .not_cgb + ld a, [wBootB] + bit 0, a + jr z, .cgb + ld hl, .s_agb + jr .model +.cgb + ld hl, .s_cgb + jr .model +.not_cgb + cp $01 + jr nz, .not_dmg + ld hl, .s_dmg + jr .model +.not_dmg + ld hl, .s_mgb +.model + call kputs + ld hl, .s_boota + call kputs + ld a, [wBootA] + call kputhex + ld a, ")" + call kputc + ld a, 10 + call kputc + + ; cart: the header describes the very cartridge we run from + ld hl, .s_cart + call kputs + ld a, [$0147] ; cart type + cp $19 + jr c, .rawtype + cp $1F + jr nc, .rawtype + ld hl, .s_mbc5 + call kputs + jr .romsize +.rawtype + ld hl, .s_type + call kputs + ld a, [$0147] + call kputhex +.romsize + ld hl, .s_rom + call kputs + ld a, [$0148] ; ROM size code: 32K << code + cp 9 + jr nc, .romq + add a ; *2: word index into the pointer table + ld e, a + ld d, 0 + ld hl, .romtab + add hl, de + ld a, [hl+] + ld h, [hl] + ld l, a + jr .romp +.romq + ld hl, .s_unk +.romp + call kputs + ld hl, .s_sram + call kputs + ld a, [$0149] ; cart RAM size code + cp 6 + jr nc, .ramq + add a + ld e, a + ld d, 0 + ld hl, .ramtab + add hl, de + ld a, [hl+] + ld h, [hl] + ld l, a + jr .ramp +.ramq + ld hl, .s_unk +.ramp + call kputs + ld hl, .s_sram2 + call kputs + + ; memory map: hardware constants of the CGB + ld hl, .s_mem + call kputs + + ; processes + programs: link-time shape of the kernel + ld hl, .s_proc + call kputs + ld hl, ProgramTableEnd - ProgramTable ; bytes; 4 per entry + ld a, l + srl h + rra + srl h + rra ; /4 (table < 1K, fits in A) + call kputdec + ld hl, .s_progs + call kputs + ret + +.s_kernel: db "gbos sm83 microkernel\n", 0 +.s_console: db "console: ", 0 +.s_cgb: db "CGB", 0 +.s_agb: db "AGB", 0 +.s_dmg: db "DMG", 0 +.s_mgb: db "MGB", 0 +.s_boota: db " (boot a=$", 0 +.s_cart: db "cart: ", 0 +.s_mbc5: db "mbc5", 0 +.s_type: db "type $", 0 +.s_rom: db ", ", 0 +.s_sram: db " rom, ", 0 +.s_sram2: db " sram\n", 0 +.s_unk: db "?", 0 +.s_mem: db "mem: 32K wram 16K vram 127B hram\n", 0 +.s_proc: db "proc: {d:MAX_PROCS} slots, ", 0 +.s_progs: db " programs\n", 0 +.romtab: dw .r0, .r1, .r2, .r3, .r4, .r5, .r6, .r7, .r8 +.r0: db "32K",0 +.r1: db "64K",0 +.r2: db "128K",0 +.r3: db "256K",0 +.r4: db "512K",0 +.r5: db "1M",0 +.r6: db "2M",0 +.r7: db "4M",0 +.r8: db "8M",0 +.ramtab: dw .m0, .m1, .m2, .m3, .m4, .m5 +.m0: db "no",0 +.m1: db "2K",0 +.m2: db "8K",0 +.m3: db "32K",0 +.m4: db "128K",0 +.m5: db "64K",0 + +; ----------------------------------------------------------------------------- +; boot_net - after net_init: the link is the network. +; ----------------------------------------------------------------------------- +boot_net:: + ld hl, .s + call kputs + ret +.s: db "net: slip on link port, {d:MAX_SOCKS} sockets\n", 0 + +; ----------------------------------------------------------------------------- +; boot_fs - after fs_init: mounted vs freshly formatted, and free blocks +; (popcount of clear bits in the block bitmap fs_init left in fs_bmbuf). +; ----------------------------------------------------------------------------- +boot_fs:: + ld hl, .s_fs + call kputs + ld a, [wBootFsFresh] + or a + jr z, .mounted + ld hl, .s_fresh + call kputs + jr .count +.mounted + ld hl, .s_mount + call kputs +.count + ld hl, fs_bmbuf + ld b, FS_NBLOCKS / 8 + ld c, 0 ; free-block count +.byte + ld a, [hl+] + cpl ; set bits = free blocks + ld e, 8 +.bit + rra + jr nc, .nofree + inc c +.nofree + dec e + jr nz, .bit + dec b + jr nz, .byte + ld a, c + call kputdec + ld hl, .s_of + call kputs + ld a, FS_NBLOCKS + call kputdec + ld hl, .s_blkfree + call kputs + ret +.s_fs: db "fs: gbfs v{d:FS_VERSION} ", 0 +.s_mount: db "mounted, ", 0 +.s_fresh: db "formatted, ", 0 +.s_of: db "/", 0 +.s_blkfree: db " blk free\n", 0 + +; ----------------------------------------------------------------------------- +; boot_tty / boot_init - console shape, and the handoff line. +; ----------------------------------------------------------------------------- +boot_tty:: + ld hl, .s + call kputs + ret +.s: db "tty: 40x18 console, SELECT = osk\n", 0 + +boot_init:: + ld hl, .s + call kputs + ret +.s: db "init: spawning pid 1\n", 0 @@ -615,6 +615,8 @@ fs_init:: cp FS_VERSION jr z, .load .fmt + ld a, 1 + ld [wBootFsFresh], a ; report "formatted" in the boot spew call fs_format .load ld a, BLK_BITMAP diff --git a/src/kdata.asm b/src/kdata.asm index 83ed162..65a059a 100644 --- a/src/kdata.asm +++ b/src/kdata.asm @@ -62,3 +62,6 @@ wSleepLastDiv::DS 1 ; sys_sleep: previous DIV reading wKillParent::DS 1 ; scratch for sys_kill wPsBuf:: DS 2 ; scratch for sys_ps wPnStart:: DS 2 ; scratch for sys_progname +wBootA:: DS 1 ; A at entry: console model from the boot ROM +wBootB:: DS 1 ; B at entry: bit0 set = AGB (GBA in CGB mode) +wBootFsFresh::DS 1 ; fs_init formatted a blank disk this boot diff --git a/src/programs.asm b/src/programs.asm index 92c736b..6dbc584 100644 --- a/src/programs.asm +++ b/src/programs.asm @@ -237,6 +237,7 @@ ProgramTable:: dw ProgDhcp db LOW(BANK(ProgIrc)), HIGH(BANK(ProgIrc)) dw ProgIrc +ProgramTableEnd:: ; ----------------------------------------------------------------------------- ; NameTable (ROM0) - command name -> program id, searched by sys_lookup. |