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Reformat to use VASM

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pjht 2024-03-16 17:41:22 -05:00
parent 561a73e02e
commit 74ba1c2e0f
Signed by: pjht
GPG Key ID: 7B5F6AFBEC7EE78E
2 changed files with 90 additions and 89 deletions
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Tupfile
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.gitignore .gitignore
LDFLAGS = -z max-page-size=1 --orphan-handling=error -T rom.ld LDFLAGS = -z max-page-size=1 --orphan-handling=error -T rom.ld
ASFLAGS = -m68010 --register-prefix-optional ASFLAGS = -m68010 -spaces -Felf -ldots -align -quiet
: rom.68k |> m68k-elf-as $(ASFLAGS) -o %o %f |> rom.o : rom.68k |> vasmm68k_mot $(ASFLAGS) -o %o %f |> rom.o
: rom.o |> m68k-elf-ld $(LDFLAGS) -o %o %f |> rom.elf : rom.o |> m68k-elf-ld $(LDFLAGS) -o %o %f |> rom.elf
: rom.elf |> m68k-elf-objcopy -O binary %f %o |> rom.bin : rom.elf |> m68k-elf-objcopy -O binary %f %o |> rom.bin

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rom.68k
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.long fakestack, _start section .text,text
.global _start dc.l fakestack, _start
public _start
_start: _start:
move.w #0x1, d0 | Find the ROM card move.w #$1, d0 ; Find the ROM card
bra.b find_first_card bra.b find_first_card
romfindret: romfindret:
move.l a0, a2 | Save the ROM card IO base in a6 for later move.l a0, a2 ; Save the ROM card IO base in a6 for later
move.l #0x10000, a7 | Set up the stack at the end of the ROM card's RAM move.l #$10000, a7 ; Set up the stack at the end of the ROM card's RAM
bsr.w find_largest_ram | Find the largest RAM card and put the IO base in a3 bsr.w find_largest_ram ; Find the largest RAM card and put the IO base in a3
move.l a0, a3 move.l a0, a3
move.l d0, d2 move.l d0, d2
move.l #0x8100, a1 move.l #$8100, a1
bsr.w find_all_ram_cards bsr.w find_all_ram_cards
move.l #0x8100, a0 move.l #$8100, a0
bsr.w sort_ram_cards bsr.w sort_ram_cards
move.w #0x4, d0 | Find a storage card and put the IO base in a4 move.w #$4, d0 ; Find a storage card and put the IO base in a4
bsr.b find_first_card bsr.b find_first_card
move.l a0, a4 move.l a0, a4
| Transfer the bootsector load code to the ROM's ; Transfer the bootsector load code to the ROM's
| built in RAM at the start of it's IO space ; built in RAM at the start of it's IO space
move.w #(ramcode_end - ramcode), d0 | Put the length of the ramcode in d0 move.w #(ramcode_end - ramcode), d0 ; Put the length of the ramcode in d0
move.w #ramcode, a0 | Put the address of the ramcode in a0 move.w #ramcode, a0 ; Put the address of the ramcode in a0
move.l a2, a1 | Put the start of the ROM's IO space RAM in a0 move.l a2, a1 ; Put the start of the ROM's IO space RAM in a0
ramcode_loop: ramcode_loop:
move.b (a0)+, (a1)+ | Transfer a byte of ramcode to the ROM's IO space RAM move.b (a0)+, (a1)+ ; Transfer a byte of ramcode to the ROM's IO space RAM
dbra d0, ramcode_loop | Loop back if there is more to transfer dbra d0, ramcode_loop ; Loop back if there is more to transfer
jmp (a2) | Jump to the ramcode jmp (a2) ; Jump to the ramcode
ramcode: ramcode:
move.b #0x0, (0xF3, a2) | Disable the ROM move.b #$0, ($F3,a2) ; Disable the ROM
move.l #0x1, (a3) | Enable the RAM at base 0x0 move.l #$1, (a3) ; Enable the RAM at base $0
cmpi.l #0x1000000, d2 cmpi.l #$1000000, d2
bcs.b sp_ok bcs.b sp_ok
move.l #0xff0000, d2 move.l #$ff0000, d2
sp_ok: sp_ok:
move.l d2, a7 move.l d2, a7
| Load sector 0 to 0x0 ; Load sector 0 to $0
move.l #0x0, (0x0, a4) | Set the sector number to 0 move.l #$0, ($0,a4) ; Set the sector number to 0
move.l #0x1, (0x4, a4) | Set the sector count to 1 move.l #$1, ($4,a4) ; Set the sector count to 1
move.l #0x0, (0xC, a4) | Set the destination address to 0x0 move.l #$0, ($C,a4) ; Set the destination address to $0
move.w #0x1, (0x8, a4) | Send a DMA read command move.w #$1, ($8,a4) ; Send a DMA read command
jmp (0x0).W | Jump to the loaded sector jmp ($0).W ; Jump to the loaded sector
ramcode_end: ramcode_end:
nop | Padding to make sure ramcode_end and find_first_card are different nop ; Padding to make sure ramcode_end and find_first_card are different
| Finds the first card with the type in d0.w, and returns it's IO base address in a0, or 0 if not found ; Finds the first card with the type in d0.w, and returns it's IO base address in a0, or 0 if not found
find_first_card: find_first_card:
move.l #0xff0000, a0 | a0 holds the address of the current card move.l #$ff0000, a0 ; a0 holds the address of the current card
ffc_loop: ffc_loop:
lea (0x100,a0), a0 | adda.l #$100,a0 ; Move to the next card lea ($100,a0), a0 ; adda.l #$100,a0 ; Move to the next card
move.w (0xfe, a0), d1 | Load the type of the card into d1 move.w ($fe,a0), d1 ; Load the type of the card into d1
beq.b ffc_done | If the type is 0 (empty slot), we have scanned all cards, so exit the loop beq.b ffc_done ; If the type is 0 (empty slot), we have scanned all cards, so exit the loop
cmp.w d0, d1 | If the card is the type we want, return with the address in a0 cmp.w d0, d1 ; If the card is the type we want, return with the address in a0
beq.b ffc_done beq.b ffc_done
bra.b ffc_loop | Loop back and check the next card bra.b ffc_loop ; Loop back and check the next card
ffc_done: ffc_done:
rts rts
| Finds the largest RAM card, and returns it's IO base address in a0 and size in d0, or 0 if not found ; Finds the largest RAM card, and returns it's IO base address in a0 and size in d0, or 0 if not found
find_largest_ram: find_largest_ram:
move.l #0x0, d0 | d0 holds the size of the largest RAM card found move.l #$0, d0 ; d0 holds the size of the largest RAM card found
move.w #0x0, a0 | a0 holds the address of the largest RAM card found move.w #$0, a0 ; a0 holds the address of the largest RAM card found
move.l #0xff0000, a1 | a1 holds the address of the current card move.l #$ff0000, a1 ; a1 holds the address of the current card
flr_loop: flr_loop:
lea (0x100,a1), a1 | adda.l #$100,a0 ; Move to the next card lea ($100,a1), a1 ; adda.l #$100,a0 ; Move to the next card
move.w (0xfe, a1), d1 | Load the type of the card into d1 move.w ($fe,a1), d1 ; Load the type of the card into d1
beq.b flr_done | If the type is 0 (empty slot), we have scanned all cards, so exit the loop beq.b flr_done ; If the type is 0 (empty slot), we have scanned all cards, so exit the loop
cmp.w #0x2, d1 | If the card isn't a RAM card, skip it cmp.w #$2, d1 ; If the card isn't a RAM card, skip it
bne.b flr_loop bne.b flr_loop
move.l (0x4, a1), d1 | Load the card's size into d1 move.l ($4,a1), d1 ; Load the card's size into d1
cmp.l d0, d1 | If the current size is less than the largest size found, go back to the start of the loop cmp.l d0, d1 ; If the current size is less than the largest size found, go back to the start of the loop
bls.b flr_loop bls.b flr_loop
move.l d1, d0 | Store the size and address of the new largest card in d0 and a0 move.l d1, d0 ; Store the size and address of the new largest card in d0 and a0
move.l a1, a0 move.l a1, a0
bra.b flr_loop | Loop back and check the next card bra.b flr_loop ; Loop back and check the next card
flr_done: flr_done:
rts rts
fakestack: fakestack:
.long romfindret dc.l romfindret
| 1KB buffer in a1 ; 1KB buffer in a1
| Returns list length in d0 ; Returns list length in d0
find_all_ram_cards: find_all_ram_cards:
move.b #0, d0 | d0 holds the number of RAM cards found. move.b #0, d0 ; d0 holds the number of RAM cards found.
move.l #0xff0000, a0 | a0 holds the address of the current card. move.l #$ff0000, a0 ; a0 holds the address of the current card.
farc_loop: farc_loop:
lea (0x100, a0), a0 | adda.l #$100,a0 ; Move to the next card lea ($100,a0), a0 ; adda.l #$100,a0 ; Move to the next card
move.w (0xfe, a0), d1 | Load the type of the card into d1 move.w ($fe,a0), d1 ; Load the type of the card into d1
beq.b farc_done | If the type is 0 (empty slot), we have scanned all cards, so exit the loop beq.b farc_done ; If the type is 0 (empty slot), we have scanned all cards, so exit the loop
cmp.w #0x2, d1 | If the card isn't a RAM card, skip it cmp.w #$2, d1 ; If the card isn't a RAM card, skip it
bne.b farc_loop bne.b farc_loop
move.l a0, (a1)+ | Write the IO base address into the buffer and advance the buffer pointer move.l a0, (a1)+ ; Write the IO base address into the buffer and advance the buffer pointer
addq.b #1, d0 | Increment the count of found RAM cards addq.b #1, d0 ; Increment the count of found RAM cards
bra.b farc_loop | Loop back and check the next card bra.b farc_loop ; Loop back and check the next card
farc_done: farc_done:
move.l #0, (a1) | Write a null terminator on the end of the list move.l #0, (a1) ; Write a null terminator on the end of the list
rts rts
| optimized bubble sort to sort RAM cards by size ; optimized bubble sort to sort RAM cards by size
| Buffer in a0 ; Buffer in a0
| Length in d0 ; Length in d0
sort_ram_cards: sort_ram_cards:
movem.l d2-d4/a2, -(a7) | Save calle-preserved registers movem.l d2-d4/a2, -(a7) ; Save calle-preserved registers
src_outer_loop: src_outer_loop:
move.b #0, d1 | d1 = newlen move.b #0, d1 ; d1 = newlen
move.b #1, d2 | d2 = i move.b #1, d2 ; d2 = i
move.l a0, a1 | a1 holds the pointer to the current pair move.l a0, a1 ; a1 holds the pointer to the current pair
src_inner_loop: src_inner_loop:
cmp.b d0, d2 | if i >= length, exit the inner loop cmp.b d0, d2 ; if i >= length, exit the inner loop
bge.b src_inner_loop_done bge.b src_inner_loop_done
move.l (a1), a2 | Read the first card's size move.l (a1), a2 ; Read the first card's size
move.l (0x4, a2), d3 move.l ($4,a2), d3
move.l (4, a1), a2 | Read the second card's size move.l (4,a1), a2 ; Read the second card's size
move.l (0x4, a2), d4 move.l ($4,a2), d4
cmp.l d3, d4 | if d4 <= d3, branch to src_pair_sorted cmp.l d3, d4 ; if d4 <= d3, branch to src_pair_sorted
bls.b src_pair_sorted bls.b src_pair_sorted
move.l (a1), d3 | Read the first value move.l (a1), d3 ; Read the first value
move.l (0x4, a1), d4 | Read the second value move.l ($4,a1), d4 ; Read the second value
move.l d3, (0x4, a1) | Write the first value where the second value was move.l d3, ($4,a1) ; Write the first value where the second value was
move.l d4, (a1)+ | Write the second value where the first value was and increment a1 for the next pair move.l d4, (a1)+ ; Write the second value where the first value was and increment a1 for the next pair
move.b d2, d1 | i = newlem move.b d2, d1 ; i = newlem
src_pair_sorted: src_pair_sorted:
addq.b #1, d2 | i++ addq.b #1, d2 ; i++
bra.b src_inner_loop bra.b src_inner_loop
src_inner_loop_done: src_inner_loop_done:
move.b d1, d0 | len = newlen move.b d1, d0 ; len = newlen
cmp #1, d0 | if n > 1, branch to outer loop cmp #1, d0 ; if n > 1, branch to outer loop
bgt.b src_outer_loop bgt.b src_outer_loop
movem.l (a7)+, d2-d4/a2 | Restore calle-preserved registers movem.l (a7)+, d2-d4/a2 ; Restore calle-preserved registers
rts rts