;    Various functions for the Interaction with the CPM Filesystem
;
;    Copyright (C) 2010 Frank Zoll
;
;    This file is part of avrcpm.
;
;    avrcpm is free software: you can redistribute it and/or modify it
;    under the terms of the GNU General Public License as published by
;    the Free Software Foundation, either version 3 of the License, or
;    (at your option) any later version.
;
;    avrcpm is distributed in the hope that it will be useful,
;    but WITHOUT ANY WARRANTY; without even the implied warranty of
;    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;    GNU General Public License for more details.
;
;    You should have received a copy of the GNU General Public License
;    along with avrcpm.  If not, see <http://www.gnu.org/licenses/>.
;
;    $Id$
;

#ifndef CPMDSK_SUPPORT
	#define CPMDSK_SUPPORT 1	
#endif

#if CPMDSK_SUPPORT

;-------------------------------------- Defines for CPM Structures
#define PART_TYPE   4
#define PART_START  8
#define PART_SIZE  12

#define PARTID_CPM 0x52		/* Partition table id */
	/* http://www.win.tue.nl/~aeb/partitions/partition_types-1.html */
;----------------------------------------------- Start of Data Segment

	.dseg

; Partition table offsets:
tmp_tbl:
	.byte	PARTENTRY_SIZE*MAXDISKS

; ---------------------------------------------- Start of Code Segment
	.cseg

; ====================================================================
; Function: Does a Disk write operation
; ====================================================================
; Parameters
; --------------------------------------------------------------------
; Registers  : none
; Variables  : [r] seekdsk		Number of Disk to Read
;			   [r] seeksec		Sector to read
;              [r] seektrk		Track  to read
; hostdsk = host disk #,  (partition #)
; hostlba = host block #, relative to partition start 
; Read/Write "hostsize" bytes to/from hostbuf
; --------------------------------------------------------------------
; Description:
; ====================================================================	

cpm_hostparam:
	lds		xl,hostdsk

.if HOSTRW_DEBUG
	mov     temp,xl
	subi	temp,-('A')
	rcall	uartputc
	printstring ": "
.endif

	rcall dsk_getpartentry		; get partition entry
		

cpm_hostlend:
	lds		temp,hostlba		; get sector to access
	lds		temp2,hostlba+1
	lds		temp3,hostlba+2

.if HOSTRW_DEBUG
	printstring "lba: "
	clr		temp4
	rcall	print_ultoa
.endif

	ldd		xl,z+5				; get disksize
	ldd		xh,z+6
	ldd		yl,z+7
	
	cp		temp,xl				; check given sector against disksize
	cpc		temp2,xh
	cpc		temp3,yl
	brcs	cpm_hp1
	
.if HOSTRW_DEBUG
	printstring ", max: "
	push	temp4
	push	temp3
	push	temp2
	push	temp
	movw	temp,x
	mov		temp3,yl
	clr		temp4
	rcall	print_ultoa
	pop		temp
	pop		temp2
	pop		temp3
	pop		temp4
	printstring " "
.endif
	
	clr		temp
	ret

cpm_hp1:
	ldd		xl,z+1			; get startsector of partition
	ldd		xh,z+2
	ldd		yl,z+3
	ldd		yh,z+4

	add		xl,temp			; add offset to startsector
	adc		xh,temp2
	adc		yl,temp3
	adc		yh,_0

.if HOSTRW_DEBUG
	printstring ", abs:"
	push	temp4
	push	temp3
	push	temp2
	push	temp
	movw	temp,x
	movw	temp3,y
	rcall	print_ultoa
	pop		temp
	pop		temp2
	pop		temp3
	pop		temp4
	printstring " "
.endif

	ori		temp,255
cpm_hpex:
	ret

; ====================================================================
; Function: Does a Disk write operation
; ====================================================================
; Parameters
; --------------------------------------------------------------------
; Registers  : none
; Variables  : [r] seekdsk		Number of Disk to Read
;			   [r] seeksec		Sector to read
;              [r] seektrk		Track  to read
; --------------------------------------------------------------------
; Description:
; ====================================================================

cpm_writehost:
.if HOSTRW_DEBUG
	printnewline
	printstring "host write "
.endif
	rcall	cpm_hostparam
	breq	cpm_rdwr_err
	
	rcall	mmcWriteSect
	tst		temp
	breq	cpm_rdwr_ok
	
	rcall	mgr_init_partitions
	cbr		temp,0x80
	breq	cpm_rdwr_err

	rcall	cpm_hostparam
	breq	cpm_rdwr_err
	rcall	mmcWriteSect
	tst		temp
	brne	cpm_rdwr_err
	rjmp	cpm_rdwr_ok

; ====================================================================
; Function: Does a Disk read operation
; ====================================================================
; Parameters
; --------------------------------------------------------------------
; Registers  : none
; Variables  : [r] seekdsk		Number of Disk to Read
;			   [r] seeksec		Sector to read
;              [r] seektrk		Track  to read
; --------------------------------------------------------------------
; Description:
; ====================================================================
cpm_readhost:
.if HOSTRW_DEBUG
	printnewline
	printstring "host read  "
.endif

	rcall	cpm_hostparam
	breq	cpm_rdwr_err
	
	rcall	mmcReadSect
	tst		temp
	breq	cpm_rdwr_ok

	rcall	mgr_init_partitions
	cbr		temp,0x80
	breq	cpm_rdwr_err

	rcall	cpm_hostparam
	breq	cpm_rdwr_err
	rcall	mmcReadSect
	tst		temp
	brne	cpm_rdwr_err

cpm_rdwr_ok:
	sts		erflag,_0
	ret

cpm_rdwr_err:
	sts		erflag,_255
	ret


; ====================================================================
; Function: Add's a CP/M Partition to the Partition table
; ====================================================================
; Parameters
; --------------------------------------------------------------------
; Registers  : none
; Variables  : [r] seekdsk		Number of Disk to Read
;			   [r] seeksec		Sector to read
;              [r] seektrk		Track  to read
; --------------------------------------------------------------------
; Description:
; ====================================================================	
cpm_add_partition:
	
	ldi temp,dskType_CPM
	st	y+,temp

	ldd	temp,z+PART_START
	st	y+,temp
	ldd	temp,z+PART_START+1
	st	y+,temp
	ldd	temp,z+PART_START+2
	st	y+,temp
	ldd	temp,z+PART_START+3
	st	y+,temp
	
	ldd	temp,z+PART_SIZE
	st	y+,temp
	ldd	temp,z+PART_SIZE+1
	st	y+,temp
	ldd	temp,z+PART_SIZE+2
	st	y+,temp
	ldd	temp,z+PART_SIZE+3
	st	y+,temp
	ret
		
#endif