From 9e48568e227637b1a3e9d571935e0dfec669ed7b Mon Sep 17 00:00:00 2001 From: pjht Date: Fri, 18 Nov 2022 16:05:13 -0600 Subject: [PATCH] Update to sector size of 512 --- boot/boot.68k | 55 ++++++++++++++++++++++++++++++------------------ initrd_maker.rs | 16 ++++++++------ kernel/main.68k | 3 +++ rom.bin | Bin 172 -> 188 bytes 4 files changed, 48 insertions(+), 26 deletions(-) diff --git a/boot/boot.68k b/boot/boot.68k index 1cac92a..6f70b58 100644 --- a/boot/boot.68k +++ b/boot/boot.68k @@ -3,25 +3,16 @@ _start: move.b #0x4, d0 bsr.w find_first_card | Load the header sector for the kernel binary -move.l #0x1, (a0) | Set the sector number to 1 -| Transfer 0x100 (256) bytes from the storage card's data register to 0x100 -move.w #0x100, a1 | Load a1, the destination address register, with 0x100 -move.w #0xFF, d0 | Load d0 with the sector size - 1. -hdr_sector_loop: -move.b (4, a0), (a1)+ | Transfer a byte of sector data to the destination -dbra d0, hdr_sector_loop | Loop back if there is more to transfer -move.w (0x102), d0 | Load d0 with the number of sectors for the kernel - 1 -subq.w #0x1, d0 +move.l #0x200, a1 | Set the destination address to 0x200 +move.l #0x1, d0 | Set the starting sector number to 1 +move.l #0x1, d1 | Set the sector count to 1 +bsr.w read_sectors | load the ELF kernel binary off the disk -move.l #0x2, (a0) | Set the sector number to 2 -| Transfer 0x100 (256) * d0 bytes from the storage card's data register to 0xA000 -move.l #0xA000, a1 | Load a1, the destination address register, with 0xA000 -sectors_loop: -move.w #0xFF, d1 | Load d0 with the sector size - 1. -sector_loop: -move.b (4, a0), (a1)+ | Transfer a byte of sector data to the destination -dbra d1, sector_loop | Loop back if there is more to transfer -dbra d0, sectors_loop | Loop back if there are more sectors to transfer +move.l #0xA000, a1 | Set the destination address to 0xA000 +move.l #0x2, d0 | Set the starting sector number to 2 +clr.l d1 +move.w (0x202), d1 | Set the sector count +bsr.b read_sectors move.l (0xA01C), d0 | Load the offset of the program headers in the file move.l #0xA000, a0 | Put the address of the program headers in a0 adda.w d0, a0 @@ -72,8 +63,32 @@ ffc_done: rts -.if . != 256 -.org 255 +| Reads sectors from a storage card +| Card base in a0 +| Destination in a1 +| Start sector in d0.l +| Sector count in d1.l +| Clobbers a1, d1 +read_sectors: +move.l d0, (a0) | Set the sector number +move.l d1, (4, a0) | Set the sector count +move.w #0x0, (8, a0) | Issue a read command +| Transfer 0x200 (512) * sector_count bytes from the storage card's data register to (a1) +lsl.l #8, d1 | d0 = d0 * 256 to compute the number of words to transfer +subq.l #0x1, d1 | Subtract 1 from the word count to account for the extra loop done by dbra +bra.b rs_loop +rs_loop_swap: +swap.w d1 +rs_loop: +move.w (0xA, a0), (a1)+ | Transfer a word of sector data to the destination +dbra.w d1, rs_loop +swap.w d1 +dbra.w d1, rs_loop_swap +rts + +.if . != 512 +.org 511 .byte 0 .endif + diff --git a/initrd_maker.rs b/initrd_maker.rs index 8734c87..9704e4f 100644 --- a/initrd_maker.rs +++ b/initrd_maker.rs @@ -5,7 +5,8 @@ use std::{ path::Path, }; -const BLOCK_SIZE: u16 = 256; +const BLOCK_SIZE: u16 = 512; +const MAX_NAME_LEN: u16 = BLOCK_SIZE - 8; fn main() { let mut archive = File::create("initrd").expect("Could not open initrd"); @@ -13,9 +14,12 @@ fn main() { let file_path = Path::new(&file_path); let file_name = file_path.file_name().unwrap(); let file_name_len = - u8::try_from(file_name.len()).expect("File name length greater than 256 bytes"); - if file_name_len > 252 { - panic!("File {:?} has name longer than 252 bytes", file_name); + u16::try_from(file_name.len()).expect("File name length greater than 256 bytes"); + if file_name_len > MAX_NAME_LEN { + panic!( + "File {:?} has name longer than {} bytes", + file_name, MAX_NAME_LEN + ); } let mut file = File::open(file_path).expect("File did not exist"); let length = u16::try_from(file.metadata().expect("Could not get file metadata").len()) @@ -24,7 +28,7 @@ fn main() { let mut header_block = Vec::new(); header_block.extend_from_slice(&length.to_be_bytes()); header_block.extend_from_slice(&file_num_blocks.to_be_bytes()); - header_block.push(file_name_len); + header_block.extend_from_slice(&file_name_len.to_be_bytes()); header_block.extend_from_slice(file_name.to_str().unwrap().as_bytes()); header_block.push(0); header_block.resize(BLOCK_SIZE as usize, 0); @@ -41,6 +45,6 @@ fn main() { } } archive - .write_all(&[0; 256]) + .write_all(&[0; BLOCK_SIZE as usize]) .expect("Could not write to initrd"); } diff --git a/kernel/main.68k b/kernel/main.68k index 0d216f6..d9c5edf 100644 --- a/kernel/main.68k +++ b/kernel/main.68k @@ -1,3 +1,6 @@ .global _start _start: + move.b #'H', 0xFF0200 + move.b #'i', 0xFF0200 + move.b #0xA, 0xFF0200 stop #0x2700 diff --git a/rom.bin b/rom.bin index 830090300fb7eacdd0a9d6b79ec45cb63a6887db..f8b80044bec89b43a99d58d34672fc4755a7990b 100644 GIT binary patch delta 163 zcmZ3(xQ9`Tfq`KM5OWCFFfb;h>3I0RWB8C*rsbi>02E&SH zhIFQc4}PTu3_z0@l)$piFM+a}Kv@wUMh2#|4@#O0ESnngUnnptcqTmZD+SuX2LS4Q BDue(4 delta 147 zcmdnPxQ0=W0RlMeY8X}s*f20Agy?wqzhiipn4;yO#{d*zNp#ZiFtB0JGN@s&nW&`{ zGx;Qt_h0A@154nE|G)fxFfjNPsWT|lF#Km=aD2hYAf&t8LpoE!2fxw+hKVPX oz;eznfpVHaIgw2^3`}Vslr$MwHZ|nGP+(N>OnBs13Ur7N0GaeE$^ZZW