https://git.reactos.org/?p=reactos.git;a=commitdiff;h=065afd93fd35cb8a9717d901649bee97d71d1a35
commit 065afd93fd35cb8a9717d901649bee97d71d1a35 Author: Dmitry Borisov <[email protected]> AuthorDate: Sun Jan 19 00:16:23 2020 +0600 Commit: Hermès BÉLUSCA - MAÏTO <[email protected]> CommitDate: Sat Jan 18 19:16:23 2020 +0100 [FREELDR] Add FAT12 file system boot sector for NEC PC-98 series (#2025) The first part of PC-98 Port - https://reactos.org/wiki/PC-98 - Add FAT12 file system boot sector for NEC PC-98 series. - Add a new build target for a PC-98 bootable floppy disk. - Add a new sub-architecture into config.cmake. --- boot/freeldr/bootsect/CMakeLists.txt | 4 + boot/freeldr/bootsect/pc98/fat12fdd.S | 501 ++++++++++++++++++++++++++++++++++ boot/freeldr/freeldr/CMakeLists.txt | 8 + sdk/cmake/config.cmake | 2 +- 4 files changed, 514 insertions(+), 1 deletion(-) diff --git a/boot/freeldr/bootsect/CMakeLists.txt b/boot/freeldr/bootsect/CMakeLists.txt index 411750ac7a0..c847a998fa2 100644 --- a/boot/freeldr/bootsect/CMakeLists.txt +++ b/boot/freeldr/bootsect/CMakeLists.txt @@ -8,6 +8,10 @@ if(ARCH STREQUAL "i386" OR ARCH STREQUAL "amd64") CreateBootSectorTarget(fat32 ${CMAKE_CURRENT_SOURCE_DIR}/fat32.S ${CMAKE_CURRENT_BINARY_DIR}/fat32.bin 7c00) CreateBootSectorTarget(btrfsvbr ${CMAKE_CURRENT_SOURCE_DIR}/btrfs.S ${CMAKE_CURRENT_BINARY_DIR}/btrfs.bin 7c00) + if(SARCH STREQUAL "pc98") + CreateBootSectorTarget(fat12pc98 ${CMAKE_CURRENT_SOURCE_DIR}/pc98/fat12fdd.S ${CMAKE_CURRENT_BINARY_DIR}/pc98/fat12fdd.bin 7c00) + endif() + ## New versions using FATY.S (experimental) # add_definitions(-DFAT12) # CreateBootSectorTarget(fat_new ${CMAKE_CURRENT_SOURCE_DIR}/faty.S ${CMAKE_CURRENT_BINARY_DIR}/fat_new.bin 7c00) diff --git a/boot/freeldr/bootsect/pc98/fat12fdd.S b/boot/freeldr/bootsect/pc98/fat12fdd.S new file mode 100644 index 00000000000..51ebfec05c4 --- /dev/null +++ b/boot/freeldr/bootsect/pc98/fat12fdd.S @@ -0,0 +1,501 @@ +/* + * PROJECT: FreeLoader + * LICENSE: GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later) + * PURPOSE: FAT12 file system boot sector for NEC PC-98 series + * NOTES: The source code in this file is based on the Brian Palmer's work + * (boot/freeldr/bootsect/fat.S) + * COPYRIGHT: Copyright 2019 Dmitry Borisov ([email protected]) + */ + +#include <asm.inc> +#include <freeldr/include/arch/pc/x86common.h> + +#define BP_REL(x) [bp + x - offset start] +#define VGA_WIDTH 80 +#define VGA_HEIGHT 25 + +/* + * See https://www.webtech.co.jp/company/doc/undocumented_mem/memsys.txt + * At segment 0000h + */ +#define BOOT_DAUA HEX(0584) + +DataAreaStartHigh = 2 +DataAreaStartLow = 4 +BiosCHSDriveSizeHigh = 6 +BiosCHSDriveSizeLow = 8 +BiosCHSDriveSize = 8 +ReadSectorsOffset = 10 +ReadClusterOffset = 12 +PutCharsOffset = 14 +BootSectorStackTop = HEX(7C00) - 16 + +if 0 +.macro DEBUG_STOP + hlt + jmp short $ - 1 +.endm + +.macro DEBUG_STEP + push ax + xor ah, ah + int HEX(18) // Wait for a keypress + pop ax +.endm +endif + +// org 7C00h + +.code16 + +start: + jmp main + nop + +// After running fatten tool it overwrites (BPB & EBPB) +OEMName: + .ascii "FrLdr1.0" +BytesPerSector: + .word 512 +SectsPerCluster: + .byte 1 +ReservedSectors: + .word 1 +NumberOfFats: + .byte 2 +MaxRootEntries: + .word 224 +TotalSectors: + .word 2880 +MediaDescriptor: + .byte HEX(0f0) +SectorsPerFat: + .word 9 +SectorsPerTrack: + .word 18 +NumberOfHeads: + .word 2 +HiddenSectors: + .long 0 +TotalSectorsBig: + .long 0 +BootDrive: + .byte HEX(0ff) +Reserved: + .byte 0 +ExtendSig: + .byte HEX(29) +SerialNumber: + .long 00000000 +VolumeLabel: + .ascii "NO NAME " +FileSystem: + .ascii "FAT12 " + +/* + * Real-mode entry point + */ +main: + xor ax, ax // Setup segment registers: + mov ds, ax // Make DS correct + mov es, ax // Make ES correct + mov ss, ax // Make SS correct + mov bp, HEX(7C00) + mov sp, BootSectorStackTop // Stack grows downwards from BootSectorStackTop + +if 0 // It would have been nice to have had this check... + mov ax, HEX(1000) // Detecting hardware + + /* + * INSTALLATION CHECK interrupt + * See http://www.ctyme.com/intr/rb-2293.htm + */ + int HEX(1A) + cmp ax, HEX(1000) + je HardwareError // An IBM-compatible PC +endif + + /* + * IBM PC here: NEC PC-98 here: + * ESI = 000E:0000 ESI = 0000:0000 + * EDI = 0000:070C EDI = 0000:0000 + * EBP = 0000:7C00 EBP = 0000:7C00 + * ESP = 0000:7BF0 ESP = 0000:7BF0 + * CS:IP = 0000:7C4E CS:IP = 1FE0:004E + */ + mov ax, word ptr ds:[BOOT_DAUA] // Get the Device Address/Unit Address (DA/UA) + mov si, ax + + push si + push cs + pop ds + xor si, si + mov ax, HEX(0000) + mov es, ax + mov di, HEX(7C00) + mov cx, 512 + rep movsw // Move our 512 bytes boot sector to the [0000:7C00] + pop si + + ljmp16 0, relocated // Jump into relocated code + +relocated: + xor ax, ax // Clean-up segments + mov es, ax + mov ds, ax + + test byte ptr ds:[HEX(501)], HEX(08) // High-resolution mode check + jz VideoTestNormalMode + mov ax, HEX(0E000) + jmp short VideoTestDone +VideoTestNormalMode: + mov ax, HEX(0A000) +VideoTestDone: + mov word ptr BP_REL(VramSegment), ax + + mov ax, si + mov byte ptr BP_REL(BootDrive), al // Save the boot drive + + /* + * Now we must find our way to the first sector of the root directory + * + * LBA = NumberOfFats * SectorsPerFat + HiddenSectors + ReservedSectors + */ + xor ax, ax + xor cx, cx + mov al, byte ptr BP_REL(NumberOfFats) // Number of fats + mul word ptr BP_REL(SectorsPerFat) // Times sectors per fat + add ax, word ptr BP_REL(HiddenSectors) + adc dx, word ptr BP_REL(HiddenSectors + 2) // Add the number of hidden sectors + add ax, word ptr BP_REL(ReservedSectors) // Add the number of reserved sectors + adc dx, cx // Add carry bit + mov word ptr [bp - DataAreaStartLow], ax // Save the starting sector of the root directory + mov word ptr [bp - DataAreaStartHigh], dx // Save it in the first 4 bytes before the boot sector + mov si, word ptr BP_REL(MaxRootEntries) // Get number of root dir entries in SI + pusha // Save 32-bit logical start sector of root dir + // DX:AX now has the number of the starting sector of the root directory + + /* + * Now calculate the size of the root directory + * + * Root directory sectors = (MaxRootEntries * 32 + BytesPerSector - 1) / BytesPerSector + */ + xor dx, dx + mov ax, 32 // Size of dir entry + mul si // Times the number of entries + mov bx, word ptr BP_REL(BytesPerSector) + add ax, bx + dec ax + div bx // Divided by the size of a sector + // AX now has the number of root directory sectors + + add word ptr [bp - DataAreaStartLow], ax // Add the number of sectors of the root directory to our other value + adc word ptr [bp - DataAreaStartHigh], cx // Now the first 4 bytes before the boot sector contain the starting sector of the data area + popa + +/* + * Reads root directory into [0000:7E00] and finds 'FREELDR SYS' + * + * Call with: + * + * DX:AX - LBA of the starting sector of the root directory + */ +LoadRootDirSector: + mov bx, HEX(7E0) // We will load the root directory sector + mov es, bx // Right after the boot sector in memory + xor bx, bx // We will load it to [0000:7E00] + xor cx, cx // Zero out CX + inc cx // Now increment it to 1, we are reading one sector + xor di, di // Zero out di + push es // Save ES because it will get incremented by 20h + call ReadSectors // Read the first sector of the root directory + pop es // Restore ES (ES:DI = 7E0:0000) + +SearchRootDirSector: + cmp byte ptr es:[di], ch // If the first byte of the directory entry is zero then we have + jz PrintFileNotFound // reached the end of the directory and FREELDR.SYS is not here so reboot + pusha // Save all registers + mov cl, 11 // Put 11 in cl (length of filename in directory entry) + mov si, offset filename // Put offset of filename string in DS:SI + repe cmpsb // Compare this directory entry against 'FREELDR SYS' + popa // Restore all the registers + jz FoundFreeLoader // If we found it then jump + dec si // SI holds MaxRootEntries, subtract one + jz PrintFileNotFound // If we are out of root dir entries then reboot + add di, 32 // Increment DI by the size of a directory entry + cmp di, HEX(0200) // Compare DI to 512 (DI has offset to next dir entry, make sure we haven't gone over one sector) + jc SearchRootDirSector // If DI is less than 512 loop again + jmp short LoadRootDirSector // Didn't find FREELDR.SYS in this directory sector, try again + +FoundFreeLoader: + /* + * We found freeldr.sys on the disk + * so we need to load the first 512 bytes of it to [0000:F800] + * ES:DI has dir entry (ES:DI == 07E0:XXXX) + */ + mov ax, word ptr es:[di + HEX(1A)] // Get start cluster + push ax // Save start cluster + push FREELDR_BASE / 16 // Put load segment on the stack and load it + pop es // Into ES so that we load the cluster at [0000:F800] + call ReadCluster // Read the cluster + pop ax // Restore start cluster of FreeLoader + + /* + * Save the addresses of needed functions so + * the helper code will know where to call them + */ + mov word ptr [bp - ReadSectorsOffset], offset ReadSectors // Save the address of ReadSectors + mov word ptr [bp - ReadClusterOffset], offset ReadCluster // Save the address of ReadCluster + mov word ptr [bp - PutCharsOffset], offset PrintString // Save the address of PrintString + + /* + * Now AX has start cluster of FreeLoader and we + * have loaded the helper code in the first 512 bytes + * of FreeLoader to 0000:F800. Now transfer control + * to the helper code. Skip the first three bytes + * because they contain a jump instruction to skip + * over the helper code in the FreeLoader image + */ + ljmp16 0, FREELDR_BASE + 3 + +/* + * Reads cluster number in AX into [ES:BX] + * + * Call with: + * + * AX - cluster number + * ES:BX - buffer to read data into + */ +ReadCluster: + /* + * StartSector = ((Cluster - 2) * SectorsPerCluster) + ReservedSectors + HiddenSectors + */ + dec ax // Adjust start cluster by 2 + dec ax // Because the data area starts on cluster 2 + xor ch, ch + mov cl, byte ptr BP_REL(SectsPerCluster) + mul cx // Times sectors per cluster + add ax, [bp - DataAreaStartLow] // Add start of data area + adc dx, [bp - DataAreaStartHigh] // Now we have DX:AX with the logical start sector of FREELDR.SYS + xor bx, bx // We will load it to [ES:0000], ES loaded before function call + +/* + * Reads logical sectors into [ES:BX] + * + * Call with: + * + * DX:AX - logical sector number to read (LBA value) + * ES:BX - buffer to read data into + * CX - number of sectors to read + */ +ReadSectors: + + .ReadSectorsLoop: + pusha + + /* + * Converting LBA (Linear Block Address) into a format CHS (Cylinder:Head:Sector) + * + * C = (LBA / SPT) / HPC + * H = (LBA / SPT) % HPC + * S = (LBA % SPT) + 1 + */ + xchg ax, cx + xchg ax, dx + xor dx, dx + div word ptr BP_REL(SectorsPerTrack) + xchg ax, cx + div word ptr BP_REL(SectorsPerTrack) // Divide logical by SectorsPerTrack + inc dx // Sectors numbering starts at 1 not 0 + xchg cx, dx + div word ptr BP_REL(NumberOfHeads) // Number of heads + + mov dh, dl // DH - head number (0-1) + mov dl, cl // DL - sector number (1-26) + mov cl, al // CL - cylinder number (0-76) + + // TODO: This should be calculated using the equation: BytesPerSector = (CH + 1) * 128 + mov ch, 2 // CH - sector size (0-4): 0 (128), 1 (256), 2 (512), 3 (1024), 4 (2048) + + mov al, byte ptr BP_REL(BootDrive) // AL - DA/UA + push bp + push bx + mov bx, word ptr BP_REL(BytesPerSector) // BX - bytes to read + pop bp // ES:BP - buffer to read data into + mov ah, HEX(56) // AH - read sectors from a floppy disk with SEEK, and use double-density format (MFM) + + /* + * Disk BIOS interrupt + * See http://radioc.web.fc2.com/column/pc98bas/bios/int1b_06.htm + */ + int HEX(1b) + + pop bp + jc PrintDiskError // CF set on failure + + popa + + inc ax // Increment sector to read + jnz .NoCarryCHS + inc dx + + .NoCarryCHS: + push bx + mov bx, es + add bx, HEX(20) // Add size of dir entry to the buffer address for the next sector + mov es, bx + pop bx + loop .ReadSectorsLoop // Increment read buffer for next sector, read next sector + + ret + +/* + * Prints a character + * + * Call with: + * + * AL - ASCII code + */ +PutChar: + push di + push es + + push word ptr BP_REL(VramSegment) + pop es + mov di, word ptr BP_REL(VramOffset) // ES:DI = VramSegment:VramOffset + .PutCharWrite: + xor ah, ah + stosw // Write ASCII directly to the VRAM + + mov word ptr BP_REL(VramOffset), di + pop es + pop di + + ret + +/* + * Prints a null-terminated string + * + * Call with: + * + * DS:SI - pointer to a string + */ +PrintString: + xor ah, ah + lodsb // Get a single char from a ptr + + or al, al + jz short .PrintEnd // Found NULL + + cmp al, HEX(0D) + jz short .PrintStringHandleCR // Found CR + + call PutChar + jmp short PrintString + + .PrintStringHandleCR: + mov ax, word ptr BP_REL(VramOffset) + mov dl, VGA_WIDTH * 2 + div dl + inc ax + mul dl + mov word ptr BP_REL(VramOffset), ax + inc si // Skip the next LF character + jmp short PrintString + +.PrintEnd: + ret + +if 0 +/* + * Displays a hardware error message and reboots + */ +HardwareError: + mov si, offset msgHardwareError + + .PrintStringVGA: + lodsb // Get a single char from a ptr + + or al, al + jz short .HardwareErrorDone // Found NULL + + mov ah, HEX(0E) // Teletype output + mov bx, 7 // BH - video page number, BL - foreground color + int HEX(10) // Display a character via TTY mode + jmp short .PrintStringVGA + +.HardwareErrorDone: + xor ax, ax + int HEX(16) // Wait for a keypress + int HEX(19) // Reboot +endif + +/* + * Displays a disk error message and reboots + */ +PrintDiskError: + mov si, offset msgDiskError // Disk error message + call PrintString // Display it + + jmp short Reboot + +/* + * Displays a file not found error message and reboots + */ +PrintFileNotFound: + mov si, offset msgNotFoundError // FreeLdr not found message + call PrintString // Display it + + jmp short Reboot + +/* + * Reboots the computer after keypress + */ +Reboot: + mov si, offset msgAnyKey // Press any key message + call PrintString // Display it + + xor ax, ax + int HEX(18) // Wait for a keypress + + /* + * Activate the CPU reset line + * See https://people.freebsd.org/~kato/pc98-arch.html#cpureset + * and http://www.webtech.co.jp/company/doc/undocumented_mem/io_cpu.txt + */ + xor ax, ax + out HEX(0F0), al + + hlt +Halt: + jmp short Halt // Spin + +VramSegment: + .word 0 +VramOffset: + .word 0 +msgDiskError: + .ascii "ERR", CR, LF, NUL +msgNotFoundError: + .ascii "NFE", CR, LF, NUL +msgAnyKey: + .ascii "Press any key", NUL +filename: + .ascii "FREELDR SYS" + +if 0 // So totally out of space here... +msgHardwareError: + .ascii "It's not PC-98", NUL +endif + + .org 509 // Pad to 509 bytes + +BootPartition: + .byte 0 + +BootSignature: + .word HEX(0AA55) // BootSector signature + +.endcode16 + +END diff --git a/boot/freeldr/freeldr/CMakeLists.txt b/boot/freeldr/freeldr/CMakeLists.txt index 37f44004ef8..784febe1f43 100644 --- a/boot/freeldr/freeldr/CMakeLists.txt +++ b/boot/freeldr/freeldr/CMakeLists.txt @@ -292,6 +292,14 @@ endif() add_dependencies(freeldr_pe asm) add_dependencies(freeldr_pe_dbg asm) +if(SARCH STREQUAL "pc98") + file(MAKE_DIRECTORY ${REACTOS_BINARY_DIR}/PC98) + add_custom_target(pc98bootfdd + COMMAND native-fatten ${REACTOS_BINARY_DIR}/PC98/ReactOS-98.IMG -format 2880 ROS98BOOT -boot ${CMAKE_BINARY_DIR}/boot/freeldr/bootsect/pc98/fat12fdd.bin -add ${CMAKE_CURRENT_BINARY_DIR}/freeldr.sys FREELDR.SYS -add ${CMAKE_SOURCE_DIR}/boot/bootdata/livecd.ini FREELDR.INI + DEPENDS native-fatten fat12pc98 freeldr + VERBATIM) +endif() + if(NOT ARCH STREQUAL "arm") concatenate_files( ${CMAKE_CURRENT_BINARY_DIR}/freeldr.sys diff --git a/sdk/cmake/config.cmake b/sdk/cmake/config.cmake index d3f596f3168..4c2305479ac 100644 --- a/sdk/cmake/config.cmake +++ b/sdk/cmake/config.cmake @@ -1,7 +1,7 @@ set(SARCH "pc" CACHE STRING "Sub-architecture to build for. Specify one of: - pc xbox") + pc pc98 xbox") set(OARCH "pentium" CACHE STRING "Generate instructions for this CPU type. Specify one of:
