Add drive error reporting

1 files changed, 182 insertions, 12 deletions

diff --git a/disk.asm b/disk.asm
index bc588f6..4177c8d 100644
--- a/disk.asm
+++ b/disk.asm
@@ -26,8 +26,116 @@ disk_info:
 	pop bp
 	ret
 
+disk_last_status:
+	push bp
+	mov bp, sp
 
-disk_info_fmt: db 'HDD(%c): INT 13h Ext: %x (%x)', CR, 0
+					; DL = drive number
+	mov ah, 01h			; BIOS get status of last drive operation
+	int 13h				; BIOS disk service
+					; carry set on error
+	mov sp, bp
+	pop bp
+	ret
+
+
+disk_convert_status:
+	push bp
+	mov bp, sp
+	pusha
+
+	cmp ax, 01h			; Avoid writing "success" message
+	jl .return
+
+	xor cx, cx
+	mov cx, ax			; AL contains the sector count
+	and cx, 00ffh			; store in CX
+	shr ax, 8			; shift error code into AL
+
+					; This block handles AL when not 00h..11h
+					; The extended error values have no real order
+	cmp al, 20h
+	je .status_20
+
+	cmp al, 40h
+	je .status_40
+
+	cmp al, 80h
+	je .status_80
+
+	cmp al, 0AAh
+	je .status_AA
+
+	cmp al, 0BBh
+	je .status_BB
+
+	cmp al, 0CCh
+	je .status_CC
+
+	cmp al, 0E0h
+	je .status_E0
+
+	cmp al, 0FFh
+	je .status_FF
+
+	jmp .convert				; No match, convert AL as-is
+
+						; Adjust error code so that it can be indexed
+						; easily by error_msg_disk_table
+	.status_20:
+		mov al, 12h
+		jmp .convert
+
+	.status_40:
+		mov al, 13h
+		jmp .convert
+
+	.status_80:
+		mov al, 14h
+		jmp .convert
+
+	.status_AA:
+		mov al, 15h
+		jmp .convert
+
+	.status_BB:
+		mov al, 16h
+		jmp .convert
+
+	.status_CC:
+		mov al, 17h
+		jmp .convert
+
+	.status_E0:
+		mov al, 18h
+		jmp .convert
+
+	.status_FF:
+		mov al, 19h
+		jmp .convert
+
+	.convert:
+		mov bx, ax			; Get array index
+		imul bx, bx, 2			; Calculate index offset
+						; in human speak: idx * (idx * WORD)
+
+		lea si, [error_msg_disk_table]	; Load address of table into source index
+		add si, bx			; Add calculated index offset
+
+	and dx, 00ffh				; get drive number
+
+	push word [si]				; error message
+	push dx					; drive number
+	push ax					; error code
+	push error_msg_disk_status_fmt
+	call printf				; Print error message
+	add sp, 8				; Clean up stack
+
+.return:
+	popa
+	mov sp, bp
+	pop bp
+	ret
 
 
 disk_lba_chs:
@@ -50,14 +158,7 @@ disk_reset:
 	int 13h			; BIOS disk service
 	jnc .success
 
-	push error_msg_disk_reset
-	call panic
-
 .success:
-	push msg_disk_reset
-	call puts
-	add sp, 2
-
 	popa
 	mov sp, bp
 	pop bp
@@ -74,27 +175,35 @@ disk_read:
 	push ax
 	push bx
 	push cx
+	push dx
 
+				; AL = Sectors to read
+				; ES:BX = Buffer address
+				; CH = Cylinder (10 bits [6 & 7 of CL are MSB])
+				; CL = Sector (5 lower bits)
+				; DH = Head
+				; DL = Drive
 	mov ah, 02h		; BIOS - read disk sectors
 	int 13h			; BIOS disk service
 
 	jnc .success
 
+	call disk_convert_status
+
 	push dx
 	call disk_reset
 	add sp, 2
 
+
+	pop dx
 	pop cx
 	pop bx
 	pop ax
 
+
 	dec di
 	jnz .readloop
 
-	push error_msg_disk_read
-	call panic
-	add sp, 2
-
 .success:
 	pop di
 	mov sp, bp
@@ -103,6 +212,7 @@ disk_read:
 
 
 ; data
+align 2
 drive0: dw 0
 
 msg_disk_reset: db "Drive reset successful.", CR, 0
@@ -111,4 +221,64 @@ msg_disk_read: db "Sector read successful.", CR, 0
 error_msg_disk_reset: db "Drive reset failed!", CR, 0
 error_msg_disk_read: db "Drive read failed!", CR, 0
 
+disk_info_fmt: db 'HDD(%c): INT 13h Ext: %x (%x)', CR, 0
+error_msg_disk_status_fmt: db 'ERROR %x: Drive %x: %s', CR, 0
+error_msg_disk:
+	eds_success: db "Success", 0					; 00h
+	eds_invalid_command: db "Invalid command", 0
+	eds_address_mark: db "Cannot find address mark", 0
+	eds_write_protected: db "Attempted write on write protected disk", 0
+	eds_sector_not_found: db "Sector not found.", 0
+	eds_reset_failed: db "Reset failed.", 0
+	eds_disk_change_line_active: db "Disk change line active", 0
+	eds_drive_parameter_activity_failed: db "Drive parameter activity failed", 0
+	eds_dma_overrun: db "DMA overrun", 0
+	eds_dma_boundary_64: db "DMA over 64kb boundary", 0
+	eds_bad_sector: db "Bad sector detected", 0
+	eds_bad_cylinder: db "Bad cylinder detected", 0
+	eds_media_type_not_found: db "Media type not found", 0
+	eds_invalid_number_of_sectors: db "Invalid number of sectors", 0
+	eds_control_data_address_mark: db "Control data address mark detected", 0
+	eds_dma_out_of_range: db "DMA out of range", 0
+	eds_crc_ecc_data_error: db "CRC/ECC data error", 0	 	; 10h
+	eds_ecc_corrected_data_error: db "ECC corrected data error", 0	; 11h
+	; Everything was normal until... this...
+	eds_controller_failure: db "Controller failure", 0		; 20h
+	eds_seek_failure: db "Seek failure", 0				; 40h
+	eds_timeout: db "Drive timed out (not ready?)", 0		; 80h
+	eds_not_ready: db "Drive not ready", 0				; AAh
+	eds_undefined_error: db "Undefined error", 0			; BBh
+	eds_write_fault: db "Write fault", 0				; CCh
+	eds_status_error: db "Status error", 0				; E0h
+	eds_sense_operation_failed: db "Sense operation failed", 0	; FFh
+
+error_msg_disk_table:				; is an array of pointers for each error message
+	dw eds_success
+	dw eds_invalid_command
+	dw eds_address_mark
+	dw eds_write_protected
+	dw eds_sector_not_found
+	dw eds_reset_failed
+	dw eds_disk_change_line_active
+	dw eds_drive_parameter_activity_failed
+	dw eds_dma_overrun
+	dw eds_dma_boundary_64
+	dw eds_bad_sector
+	dw eds_bad_cylinder
+	dw eds_media_type_not_found
+	dw eds_invalid_number_of_sectors
+	dw eds_control_data_address_mark
+	dw eds_dma_out_of_range
+	dw eds_crc_ecc_data_error
+	dw eds_ecc_corrected_data_error
+	dw eds_controller_failure
+	dw eds_seek_failure
+	dw eds_timeout
+	dw eds_not_ready
+	dw eds_undefined_error
+	dw eds_write_fault
+	dw eds_status_error
+	dw eds_sense_operation_failed
+	dw 0000h				; END of error_msg_disk_table
+
 %endif ; _DISK_ASM