[avrcpm.git] / avr / mmc.asm

;    MMC/SD-Card routines
;
;    Copyright (C) 2010 Leo C.
;
;    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/>.
;
;    $Id$
;

/* Definitions for MMC/SDC command */
#define CMD0	(0)		/* GO_IDLE_STATE */
#define CMD1	(1)		/* SEND_OP_COND (MMC) */
#define	ACMD41	(0x80+41)	/* SEND_OP_COND (SDC) */
#define CMD8	(8)		/* SEND_IF_COND */
#define CMD9	(9)		/* SEND_CSD */
#define CMD10	(10)		/* SEND_CID */
#define CMD12	(12)		/* STOP_TRANSMISSION */
#define ACMD13	(0x80+13)	/* SD_STATUS (SDC) */
#define CMD16	(16)		/* SET_BLOCKLEN */
#define CMD17	(17)		/* READ_SINGLE_BLOCK */
#define CMD18	(18)		/* READ_MULTIPLE_BLOCK */
#define CMD23	(23)		/* SET_BLOCK_COUNT (MMC) */
#define	ACMD23	(0x80+23)	/* SET_WR_BLK_ERASE_COUNT (SDC) */
#define CMD24	(24)		/* WRITE_BLOCK */
#define CMD25	(25)		/* WRITE_MULTIPLE_BLOCK */
#define CMD55	(55)		/* APP_CMD */
#define CMD58	(58)		/* READ_OCR */

/* Disk Status Bits (masks) (DSTATUS) */
#define MMCST_NOINIT	0x01	/* Drive not initialized */
#define MMCST_NODISK	0x02	/* No medium in the drive */
#define MMCST_PROTECT	0x04	/* Write protected */

/* Card type flags (masks) (CardType) */
#define CT_MMC		0x01	/* MMC ver 3 */
#define CT_SD1		0x02	/* SD ver 1 */
#define CT_SD2		0x04	/* SD ver 2 */
#define CT_SDC	(CT_SD1|CT_SD2)	/* SD */
#define CT_BLOCK	0x08	/* Block addressing */

#define	RES_OK 		0	/* 0: Successful */
#define	RES_ERROR	1	/* 1: R/W Error */
#define	RES_WRPRT	2	/* 2: Write Protected */
#define	RES_NOTRDY	3	/* 3: Not Ready */
#define	RES_PARERR	4	/* 4: Invalid Parameter */


#define SPI_MODE_0	(0<<CPOL)|(0<<CPHA)
#define SPI_MODE_1	(0<<CPOL)|(1<<CPHA)
#define SPI_MODE_2	(1<<CPOL)|(0<<CPHA)
#define SPI_MODE_3	(1<<CPOL)|(1<<CPHA)
#define SPI_MODE	SPI_MODE_0

;------------------------------------------------
; 
.macro	spi_clkslow
.if MMC_DEBUG > 1
	printstring	"SPI_CLK_SLOW "
.endif
	ldi	temp,SPI_MODE|(1<<SPE)|(1<<MSTR)|(1<<SPR1)|(1<<SPR0)	;clk/128
	out	SPCR,temp
	out	SPSR,_0
.endm

;------------------------------------------------
; 
.macro	spi_clkfast
.if MMC_DEBUG > 1
	printstring	"SPI_CLK_FAST "
.endif
	ldi	temp,SPI_MODE|(1<<SPE)|(1<<MSTR)			;clk/4
	out	SPCR,temp
#if MMC_SPI2X
	ldi	temp,(1<<SPI2X)
	out	SPSR,temp
#else
	out	SPSR,_0
#endif
.endm

;------------------------------------------------
; 
.macro	spi_disable
.if MMC_DEBUG > 1
	printstring	"SPI_DISABLE "
.endif
	out	SPCR,_0
.endm


;------------------------------------------------
;
.macro	spi_waitm
	.set	spiwl_ = PC
	sbism8	SPSR,SPIF
	rjmp	spiwl_
.endm

;------------------------------------------------

	.dseg

mmcStat:
	.byte	1
mmcCardType:
	.byte	1


	.cseg

;------------------------------------------------
; Multiply 32 bit value in yh,yl,xh,xl by 512

mul_yx_512:
	mov	yh,yl
	mov	yl,xh
	mov	xh,xl
	ldi	xl,0
	lsl	xh
	rol	yl
	rol	yh
	ret
		
;------------------------------------------------
spi_rcvr:
	out	SPDR,_255
spi_rcvr_l:
	sbism8 SPSR,SPIF
	rjmp	spi_rcvr_l
	in	temp,SPDR
.if MMC_DEBUG > 2
	printstring "<"
	rcall printhex
	printstring " "
.endif
	ret

;------------------------------------------------
spi_xmit:
.if MMC_DEBUG > 2
	printstring ">"
	rcall printhex
	printstring " "
.endif
	out	SPDR,temp
					;fall thru
spi_wait:	
	sbism8	SPSR,SPIF
	rjmp	spi_wait
	ret
	
;------------------------------------------------
; Wait for card ready 
;	return  1:OK, 0:Timeout 

mmcWaitReady:
	push	temp2
	ldi	temp2,2			;Wait for ready in timeout of 500ms.
	rcall	spi_rcvr
mmc_wrl:
	sts	delay_timer2,_255
mmc_wrl1:
	rcall	spi_rcvr
	cp	temp,_255
	brne	mmc_wrl2
	ldi	temp,1
	rjmp	mmc_wrbreak

mmc_wrl2:
	lds	temp,delay_timer2
	cpi	temp,0
	brne	mmc_wrl1
	dec	temp2
	brne	mmc_wrl		;tmp is 0 here

mmc_wrbreak:
	pop	temp2	
	tst	temp		;set flags
	ret


;------------------------------------------------
; Deselect the card and release SPI bus
;	return 0

mmcDeselect:
	sbi	P_MMC_CS,mmc_cs		; CS high
	rcall	spi_rcvr
	clr	temp
	ret

;------------------------------------------------
; Select the card and wait for ready 
;	return 255:Successful, 0:Timeout

mmcSelect:
	cbi	P_MMC_CS,mmc_cs		; CS low
	rcall	mmcWaitReady
	breq	mmcDeselect		;return via Deselect
	sbr	temp,255
	ret
	

;------------------------------------------------
; Send a command packet to MMC 
; 	temp2:	Command
;       yh..xl:	Argument
;  return:
;	temp:	0 = ok, no error
;	z-flag	1 = ok, no error
;

mmcCmd:
	sbrs	temp2,7
	rjmp	mmc_cmddo

; ACMD<n> is the command sequence of CMD55-CMD<n>	
	
	push	yh
	push	yl
	push	xh
	push	xl
	push	temp2
	ldiw	y,0
	movw	x,y
	ldi	temp2,CMD55
	rcall	mmcCmd
	pop	temp2
	pop	xl
	pop	xh
	pop	yl
	pop	yh

	cpi	temp,2
	brlo	mmc_cmddo		; fall thru, if (retval <= 1)
	
	tst	temp
	ret				; else return error

; Select the card and wait for ready

mmc_cmddo:
.if MMC_DEBUG
	sbrc	temp2,7
	rjmp	dmmccmd_nonl
	printnewline

dmmccmd_nonl:
	printstring "mmcCMD: "
	mov	temp,temp2
	cbr	temp,0x80
	rcall	printhex
	printstring " "
	push	temp2
	movw	temp,y
	rcall	printhexw
	movw	temp,x
	rcall	printhexw
	printstring " "
	pop	temp2
.endif
	rcall	mmcDeselect
	rcall	mmcSelect
	brne	mmc_cmd_p

	ldi	temp,0xFF
	rjmp	mmc_cmdexit
	
; Send command packet

mmc_cmd_p:
	mov	temp,temp2
	cbr	temp,0x80
	sbr	temp,0x40
	rcall	spi_xmit
	out	SPDR,yh
	rcall	spi_wait
	out	SPDR,yl
	rcall	spi_wait
	out	SPDR,xh
	rcall	spi_wait
	out	SPDR,xl
	rcall	spi_wait
	
	ldi	temp,0x95		;CRC for CMD0(0)
	cpi	temp2,CMD0
	breq	mmc_cmdxcrc
	ldi	temp,0x87		;CRC for CMD8(0x1AA) 
	cpi	temp2,CMD8
	breq	mmc_cmdxcrc
	ldi	temp,0x01		;Dummy CRC + Stop
mmc_cmdxcrc:
.if MMC_DEBUG
	printstring ".. "
	rcall	printhex
.endif
	rcall	spi_xmit

; Receive command response

	cpi	temp2,CMD12		; Skip a stuff byte when stop reading
	brne	mmc_cmdres
	rcall	spi_rcvr
	
; Wait for a valid response in timeout of 10 attempts

mmc_cmdres:
	push	temp2
	ldi	temp2,10
mmc_cmdrl:
	rcall	spi_rcvr
	sbrs	temp,7
	rjmp	mmc_cmdexit
	dec	temp2
	brne	mmc_cmdrl

; Return with  response value

mmc_cmdexit:
	pop	temp2
.if MMC_DEBUG
	printstring " CMDRes: "
	rcall	printhex
	printstring " "
	rcall	uart_wait_empty
.endif
	tst	temp			;set flags
	ret
	
;------------------------------------------------
; Send command and receive ocr response
; 	temp2:	Command, zl: expected cmd response
;       yh..xl:	Argument
;	return: yh..xl: ocr, z flag == 1, if return from mmcCmd was ok.

mmcCmd_ocr:

	rcall	mmcCmd

	cp	temp,zl			;
	brne	mmc_cocr_e

; Get trailing return value of R7 response

	ldi	temp2,4
	ldiw	z,0x1a			;memory address of xl
mmc_cocr1:
	rcall	spi_rcvr
	st	z+,temp
	dec	temp2
	brne	mmc_cocr1
					;z-flag =1
mmc_cocr_e:
	ret

;------------------------------------------------
; Check if 1 sec timeout
;	return Z-Flag set, if timeout

mmc_timeout_1s:
	lds	temp,delay_timer1
	tst	temp
	brne	mmc_ttex
	dec	zh
	breq	mmc_ttex
	ldi	temp,100
	sts	delay_timer1,temp
mmc_ttex:
	ret


;------------------------------------------------
;       "Public" functions
;------------------------------------------------

;------------------------------------------------
; Initialize MMC/SD card

mmcInit:
.if MMC_DEBUG 
	printnewline
	printstring	"mmcInit "
.endif
	lds	temp,mmcStat		;Set 'NO INIT' status
	sbr	temp,MMCST_NOINIT
	sts	mmcStat,temp

	spi_clkslow
	ldi	temp2,10
mmci_lp:
	rcall	spi_rcvr
	dec	temp2			;80 dummy clocks
	brne	mmci_lp

	ldi	temp3,0			;Card type
	ldi	temp2,CMD0
	ldiw	y,0
	movw	x,y
	rcall	mmcCmd			;Enter Idle state
	cpi	temp,1
	breq	mmci_1
	rjmp	mmci_lend
mmci_1:	
	ldi	zh,10			;Initialization timeout of 1000 ms.
	ldi	temp,100
	sts	delay_timer1,temp
	ldi	temp2,CMD8
	ldiw	y,0
	ldi	xh,0x01
	ldi	xl,0xAA
	ldi	zl,1
	rcall	mmcCmd_ocr
	brne	mmci_sdv1		;SDv2?

	cpi	yl,0x01			;ocr[2]
	brne	mmci_sdv1
	cpi	yh,0xAA			;ocr[3]
	brne	mmci_sdv1

; The card can work at vdd range of 2.7-3.6V.
; Wait for leaving idle state (ACMD41 with HCS bit).
	
	ldi	temp2,ACMD41
	ldi	yh,0x40
	ldi	yl,0
	ldi	xh,0
	ldi	xl,0
mmci_v2l2:
	rcall	mmcCmd
	breq	mmci_ccc
	rcall	mmc_timeout_1s
	brne	mmci_v2l2
	rjmp	mmci_sdv2end
	
; Check CCS bit in the OCR
mmci_ccc:
	ldi	temp2,CMD58
	ldi	yh,0
	ldi	zl,0
	rcall	mmcCmd_ocr

	brne	mmci_sdv2end

	sbr	temp3,CT_SD2
	sbrc	xl,6
	sbr	temp3,CT_BLOCK

mmci_sdv2end:
	rjmp	mmci_lend
	
; SDv1 or MMCv3

mmci_sdv1:
	ldi	temp2,ACMD41
	ldiw	y,0
	movw	x,y
	rcall	mmcCmd	
	cpi	temp,2
	brsh	mmci_mmcv3
	sbr	temp3,CT_SD1		;SDv1
	ldi	temp2,ACMD41
	rjmp	mmci_v1_l
mmci_mmcv3:
	sbr	temp3,CT_MMC		;MMCv3
	ldi	temp2,CMD1

; Wait for leaving idle state
mmci_v1_l:
	rcall	mmcCmd
	breq	mmci_v1_2
	rcall	mmc_timeout_1s
	brne	mmci_v1_l
	rjmp	mmci_lend		;Timeout
	
; Set R/W block length to 512
mmci_v1_2:
	ldi	temp2,CMD16		
	ldiw	x,512
	rcall	mmcCmd
	breq	mmci_lend
	ldi	temp3,0
	
mmci_lend:
	sts	mmcCardType,temp3
	rcall	mmcDeselect
	
; Initialization succeded?

	lds	temp,mmcStat
	tst	temp3
	breq	mmci_lex
	cbr	temp,MMCST_NOINIT	;Yes, clear 'NO INIT' status
	sts	mmcStat,temp
mmci_lex:

.if MMC_DEBUG
	printnewline
	printstring " CT: "
	push	temp
	lds temp,mmcCardType
	lcall	printhex
	pop	temp
	printstring " InitRes: "
	lcall	printhex
	printstring " "
.endif

	spi_disable
	ret
	
;--------------------------------------------------------------

	.equ	MMC_RDOP   = 0		;Read Operation
	.equ	MMC_RDWORD = 1		;Read Word (FAT entry)

;--------------------------------------------------------------

mmcReadSect:

.if MMC_DEBUG > 1
	printnewline
	printstring	"mmcRdSect "
.endif
	ldi	temp,(1<<MMC_RDOP)
	rjmp	mmc_rw_common

mmcReadWord:

.if MMC_DEBUG > 1
	printnewline
	printstring "mmcRdWord "
.endif
	ldi	temp,(1<<MMC_RDOP) | (1<<MMC_RDWORD) 
	rjmp	mmc_rw_common

mmcWriteSect:

.if MMC_DEBUG > 1
	printnewline
	printstring	"mmcWrSect "
.endif
	ldi	temp,0

mmc_rw_common:
	push	temp3
	mov	temp3,temp
	lds	temp,mmcStat
	ldi	temp2,RES_NOTRDY
	sbrc	temp,log2(MMCST_NOINIT)
	 rjmp	mmc_rwexit_2
	
	spi_clkfast
	lds	temp,mmcCardType
	sbrs	temp,log2(CT_BLOCK)
	 rcall	mul_yx_512		;Convert to byte address  (*512)
	
	sbrc	temp3,MMC_RDOP
	 ldi	temp2,CMD17
	sbrs	temp3,MMC_RDOP
	 ldi	temp2,CMD24
	rcall	mmcCmd
	breq	mmc_rw_1
	rjmp	mmc_rwexit_error

mmc_rw_1:
	ldiw	y,hostbuf		;aarrrgh
	sbrs	temp3,MMC_RDWORD
	 movw	 z,y
	ldiw	y,512
	sbrs	temp3,MMC_RDOP
	 rjmp	mmc_wroper

;-------------------------------------------------------------------------------
; Receive a data packet from MMC

	ldi	temp,200		;Wait for data packet in timeout of 200ms.
	sts	delay_timer1,temp
mmc_rcv_wl:
	rcall	spi_rcvr
	cp	temp,_255
	brne	mmc_rcv_start
	lds	_tmp0,delay_timer1
	cp	_tmp0,_0
	brne	mmc_rcv_wl
.if MMC_DEBUG > 1
	printstring	"TIMEOUT "
	rjmp	mmc_rcv_dbg1
.endif

mmc_rcv_start:
.if MMC_DEBUG > 1
	cpi	temp,0xFE		;If not valid data token, 
	breq	mmc_rcv_dbg1
	printstring	"Token: "
	lcall	printhex
	printstring	" "
mmc_rcv_dbg1:
.endif
	cpi	temp,0xFE		;If not valid data token, 
	breq	mmc_rw_2
	rjmp	mmc_rwexit_error
mmc_rw_2:

	rcall	spi_rcvr		;Shift in first byte.
.if MMC_DEBUG > 3
	printnewline
	lcall	printhex
	printstring	" "
.endif
	out	SPDR,_255		;Start shift in next byte.

	sbrs	temp3,MMC_RDWORD
	 rjmp	mmc_rcv_readloop

; discard x-1 bytes

mmc_rcvw_rl:
	sbiw	yl,1
	breq	mmc_rcv_rlend
	cp	zl,_0
	cpc	zh,_0
	breq	mmc_rcvw_sto

	sbiw	zl,1
	spi_waitm
	in	temp,SPDR
	out	SPDR,_255
	rjmp	mmc_rcvw_rl

; read next two bytes

mmc_rcvw_sto:
	mov 	zl,temp
	spi_waitm
	in	temp,SPDR
	out	SPDR,_255
	mov 	zh,temp

; discard the rest

mmc_rcvw_rl2:
	sbiw	yl,1
	breq	mmc_rcv_rlend
	spi_waitm
	in	temp,SPDR
	out	SPDR,_255
	rjmp	mmc_rcvw_rl2

; read sector, store in buffer

mmc_rcv_readloop:
	sbiw	yl,1
	breq	mmc_rcv_rle
	st	z+,temp
	spi_waitm
	in	temp,SPDR
.if MMC_DEBUG > 3
	lcall	printhex
	printstring	" "
.endif
	out	SPDR,_255
	rjmp	mmc_rcv_readloop

mmc_rcv_rle:
	st	z+,temp			;Store last byte in buffer 
mmc_rcv_rlend:
.if MMC_DEBUG > 3
	printnewline
.endif
	rcall	spi_wait		;while SPI module shifts in crc part1.
	rcall	spi_rcvr		;Read second crc.
	
	ldi	temp2,RES_OK		;Return success
	rjmp	mmc_rwexit

	
;-------------------------------------------------------------------------------
; Send a data packet to MMC

mmc_wroper:

.if MMC_DEBUG > 2
;	printnewline
	printstring	"mmcXMIT "
.endif
	rcall	mmcWaitReady
	breq	mmc_rwexit_error

	ldi	temp,0xFE		;Data token
	out	SPDR,temp
mmc_x_loop:
	ld	temp,z+
	spi_waitm
	out	SPDR,temp
	sbiw	yl,1
	brne	mmc_x_loop
	
	rcall	spi_wait
	ldi	temp,0xFF		;dummy crc
	rcall	spi_xmit
	rcall	spi_xmit
	rcall	spi_rcvr
.if MMC_DEBUG > 2
	printstring	"XMITRes: "
	lcall	printhex
	printstring	" "
.endif
	andi	temp,0x1F		;If not accepted, return with error
	cpi	temp,0x05
	ldi	temp2,RES_OK		;Return success
	breq	mmc_rwexit

mmc_rwexit_error:
	ldi	temp2,RES_ERROR
mmc_rwexit:
	rcall	mmcDeselect
	spi_disable
mmc_rwexit_2:
	mov	temp,temp2

.if MMC_DEBUG > 1
	sbrc	temp3,MMC_RDOP
	rjmp	mmc_dbg_rder

	printstring "WrSectRes: "
	rjmp	mmc_dbg_rwerex

mmc_dbg_rder:
	sbrc	temp3,MMC_RDWORD
	rjmp	mmc_dbg_rdwder
	printstring "RdSectRes: "
	rjmp	mmc_dbg_rwerex

mmc_dbg_rdwder:
	printstring "RdWordRes: "
mmc_dbg_rwerex:
	lcall	printhex
	printstring	" "
.endif
	pop	temp3
	ret

;--------------------------------------------------------------
; vim:set ts=8 noet nowrap
Commit	Line	Data
9c15f366 L	1	; MMC/SD-Card routines
	2	;
	3	; Copyright (C) 2010 Leo C.
	4	;
	5	; This file is part of avrcpm.
	6	;
	7	; avrcpm is free software: you can redistribute it and/or modify it
	8	; under the terms of the GNU General Public License as published by
	9	; the Free Software Foundation, either version 3 of the License, or
	10	; (at your option) any later version.
	11	;
	12	; avrcpm is distributed in the hope that it will be useful,
	13	; but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	; GNU General Public License for more details.
	16	;
	17	; You should have received a copy of the GNU General Public License
	18	; along with avrcpm. If not, see <http://www.gnu.org/licenses/>.
	19	;
	20	; $Id$
	21	;
	22
	23	/* Definitions for MMC/SDC command */
	24	#define CMD0 (0) /* GO_IDLE_STATE */
	25	#define CMD1 (1) /* SEND_OP_COND (MMC) */
	26	#define ACMD41 (0x80+41) /* SEND_OP_COND (SDC) */
	27	#define CMD8 (8) /* SEND_IF_COND */
	28	#define CMD9 (9) /* SEND_CSD */
	29	#define CMD10 (10) /* SEND_CID */
	30	#define CMD12 (12) /* STOP_TRANSMISSION */
	31	#define ACMD13 (0x80+13) /* SD_STATUS (SDC) */
	32	#define CMD16 (16) /* SET_BLOCKLEN */
	33	#define CMD17 (17) /* READ_SINGLE_BLOCK */
	34	#define CMD18 (18) /* READ_MULTIPLE_BLOCK */
	35	#define CMD23 (23) /* SET_BLOCK_COUNT (MMC) */
	36	#define ACMD23 (0x80+23) /* SET_WR_BLK_ERASE_COUNT (SDC) */
	37	#define CMD24 (24) /* WRITE_BLOCK */
	38	#define CMD25 (25) /* WRITE_MULTIPLE_BLOCK */
	39	#define CMD55 (55) /* APP_CMD */
	40	#define CMD58 (58) /* READ_OCR */
	41
34527fc2	42	/* Disk Status Bits (masks) (DSTATUS) */
9c15f366 L	43	#define MMCST_NOINIT 0x01 /* Drive not initialized */
	44	#define MMCST_NODISK 0x02 /* No medium in the drive */
	45	#define MMCST_PROTECT 0x04 /* Write protected */
	46
34527fc2	47	/* Card type flags (masks) (CardType) */
9c15f366 L	48	#define CT_MMC 0x01 /* MMC ver 3 */
	49	#define CT_SD1 0x02 /* SD ver 1 */
	50	#define CT_SD2 0x04 /* SD ver 2 */
	51	#define CT_SDC (CT_SD1\|CT_SD2) /* SD */
	52	#define CT_BLOCK 0x08 /* Block addressing */
	53
	54	#define RES_OK 0 /* 0: Successful */
	55	#define RES_ERROR 1 /* 1: R/W Error */
	56	#define RES_WRPRT 2 /* 2: Write Protected */
	57	#define RES_NOTRDY 3 /* 3: Not Ready */
	58	#define RES_PARERR 4 /* 4: Invalid Parameter */
	59
4160d270 L	60
	61	#define SPI_MODE_0 (0<<CPOL)\|(0<<CPHA)
	62	#define SPI_MODE_1 (0<<CPOL)\|(1<<CPHA)
	63	#define SPI_MODE_2 (1<<CPOL)\|(0<<CPHA)
	64	#define SPI_MODE_3 (1<<CPOL)\|(1<<CPHA)
	65	#define SPI_MODE SPI_MODE_0
	66
9c15f366 L	67	;------------------------------------------------
	68	;
	69	.macro spi_clkslow
	70	.if MMC_DEBUG > 1
	71	printstring "SPI_CLK_SLOW "
	72	.endif
4160d270	73	ldi temp,SPI_MODE\|(1<<SPE)\|(1<<MSTR)\|(1<<SPR1)\|(1<<SPR0) ;clk/128
9c15f366 L	74	out SPCR,temp
	75	out SPSR,_0
	76	.endm
	77
	78	;------------------------------------------------
	79	;
	80	.macro spi_clkfast
	81	.if MMC_DEBUG > 1
	82	printstring "SPI_CLK_FAST "
	83	.endif
4160d270	84	ldi temp,SPI_MODE\|(1<<SPE)\|(1<<MSTR) ;clk/4
9c15f366 L	85	out SPCR,temp
	86	#if MMC_SPI2X
	87	ldi temp,(1<<SPI2X)
	88	out SPSR,temp
	89	#else
	90	out SPSR,_0
	91	#endif
	92	.endm
	93
	94	;------------------------------------------------
	95	;
	96	.macro spi_disable
	97	.if MMC_DEBUG > 1
	98	printstring "SPI_DISABLE "
	99	.endif
	100	out SPCR,_0
	101	.endm
	102
	103
	104	;------------------------------------------------
	105	;
	106	.macro spi_waitm
	107	.set spiwl_ = PC
	108	sbism8 SPSR,SPIF
	109	rjmp spiwl_
	110	.endm
	111
	112	;------------------------------------------------
	113
	114	.dseg
	115
	116	mmcStat:
	117	.byte 1
	118	mmcCardType:
	119	.byte 1
9c15f366 L	120
	121
	122	.cseg
	123
	124	;------------------------------------------------
	125	; Multiply 32 bit value in yh,yl,xh,xl by 512
	126
	127	mul_yx_512:
	128	mov yh,yl
	129	mov yl,xh
	130	mov xh,xl
	131	ldi xl,0
	132	lsl xh
	133	rol yl
	134	rol yh
	135	ret
	136
	137	;------------------------------------------------
	138	spi_rcvr:
	139	out SPDR,_255
	140	spi_rcvr_l:
	141	sbism8 SPSR,SPIF
	142	rjmp spi_rcvr_l
	143	in temp,SPDR
	144	.if MMC_DEBUG > 2
9c15f366 L	145	printstring "<"
	146	rcall printhex
	147	printstring " "
9c15f366 L	148	.endif
	149	ret
	150
	151	;------------------------------------------------
	152	spi_xmit:
	153	.if MMC_DEBUG > 2
	154	printstring ">"
	155	rcall printhex
	156	printstring " "
	157	.endif
	158	out SPDR,temp
	159	;fall thru
	160	spi_wait:
	161	sbism8 SPSR,SPIF
	162	rjmp spi_wait
	163	ret
	164
	165	;------------------------------------------------
	166	; Wait for card ready
	167	; return 1:OK, 0:Timeout
	168
	169	mmcWaitReady:
	170	push temp2
	171	ldi temp2,2 ;Wait for ready in timeout of 500ms.
	172	rcall spi_rcvr
	173	mmc_wrl:
	174	sts delay_timer2,_255
	175	mmc_wrl1:
	176	rcall spi_rcvr
	177	cp temp,_255
	178	brne mmc_wrl2
	179	ldi temp,1
	180	rjmp mmc_wrbreak
	181
	182	mmc_wrl2:
	183	lds temp,delay_timer2
	184	cpi temp,0
	185	brne mmc_wrl1
	186	dec temp2
	187	brne mmc_wrl ;tmp is 0 here
	188
	189	mmc_wrbreak:
	190	pop temp2
	191	tst temp ;set flags
	192	ret
	193
	194
	195	;------------------------------------------------
	196	; Deselect the card and release SPI bus
	197	; return 0
	198
	199	mmcDeselect:
	200	sbi P_MMC_CS,mmc_cs ; CS high
	201	rcall spi_rcvr
	202	clr temp
	203	ret
	204
	205	;------------------------------------------------
	206	; Select the card and wait for ready
	207	; return 255:Successful, 0:Timeout
	208
	209	mmcSelect:
	210	cbi P_MMC_CS,mmc_cs ; CS low
	211	rcall mmcWaitReady
212	breq mmcDeselect ;return via Deselect
213	sbr temp,255
214	ret
215
216
217	;------------------------------------------------
218	; Send a command packet to MMC
219	; temp2: Command
220	; yh..xl: Argument
34527fc2 L	221	; return:
	222	; temp: 0 = ok, no error
	223	; z-flag 1 = ok, no error
	224	;
9c15f366 L	225
	226	mmcCmd:
	227	sbrs temp2,7
	228	rjmp mmc_cmddo
	229
	230	; ACMD<n> is the command sequence of CMD55-CMD<n>
	231
	232	push yh
	233	push yl
	234	push xh
	235	push xl
	236	push temp2
	237	ldiw y,0
	238	movw x,y
	239	ldi temp2,CMD55
	240	rcall mmcCmd
	241	pop temp2
	242	pop xl
	243	pop xh
	244	pop yl
	245	pop yh
	246
	247	cpi temp,2
	248	brlo mmc_cmddo ; fall thru, if (retval <= 1)
	249
	250	tst temp
	251	ret ; else return error
	252
	253	; Select the card and wait for ready
	254
	255	mmc_cmddo:
	256	.if MMC_DEBUG
	257	sbrc temp2,7
	258	rjmp dmmccmd_nonl
	259	printnewline
	260
	261	dmmccmd_nonl:
	262	printstring "mmcCMD: "
	263	mov temp,temp2
	264	cbr temp,0x80
	265	rcall printhex
	266	printstring " "
	267	push temp2
	268	movw temp,y
	269	rcall printhexw
	270	movw temp,x
	271	rcall printhexw
	272	printstring " "
	273	pop temp2
	274	.endif
	275	rcall mmcDeselect
	276	rcall mmcSelect
	277	brne mmc_cmd_p
	278
	279	ldi temp,0xFF
	280	rjmp mmc_cmdexit
	281
	282	; Send command packet
	283
	284	mmc_cmd_p:
	285	mov temp,temp2
	286	cbr temp,0x80
	287	sbr temp,0x40
	288	rcall spi_xmit
289	out SPDR,yh
290	rcall spi_wait
291	out SPDR,yl
292	rcall spi_wait
293	out SPDR,xh
294	rcall spi_wait
295	out SPDR,xl
296	rcall spi_wait
297
298	ldi temp,0x95 ;CRC for CMD0(0)
299	cpi temp2,CMD0
300	breq mmc_cmdxcrc
301	ldi temp,0x87 ;CRC for CMD8(0x1AA)
302	cpi temp2,CMD8
303	breq mmc_cmdxcrc
304	ldi temp,0x01 ;Dummy CRC + Stop
305	mmc_cmdxcrc:
306	.if MMC_DEBUG
307	printstring ".. "
308	rcall printhex
309	.endif
310	rcall spi_xmit
311
312	; Receive command response
313
314	cpi temp2,CMD12 ; Skip a stuff byte when stop reading
315	brne mmc_cmdres
316	rcall spi_rcvr
317
318	; Wait for a valid response in timeout of 10 attempts
319
320	mmc_cmdres:
825ecc9d L	321	push temp2
825ecc9d L	322	ldi temp2,10
9c15f366 L	323	mmc_cmdrl:
	324	rcall spi_rcvr
	325	sbrs temp,7
	326	rjmp mmc_cmdexit
825ecc9d	327	dec temp2
9c15f366 L	328	brne mmc_cmdrl
	329
	330	; Return with response value
	331
	332	mmc_cmdexit:
825ecc9d	333	pop temp2
9c15f366 L	334	.if MMC_DEBUG
	335	printstring " CMDRes: "
	336	rcall printhex
	337	printstring " "
	338	rcall uart_wait_empty
	339	.endif
	340	tst temp ;set flags
	341	ret
	342
08716d4f L	343	;------------------------------------------------
	344	; Send command and receive ocr response
	345	; temp2: Command, zl: expected cmd response
	346	; yh..xl: Argument
	347	; return: yh..xl: ocr, z flag == 1, if return from mmcCmd was ok.
	348
	349	mmcCmd_ocr:
	350
	351	rcall mmcCmd
	352
	353	cp temp,zl ;
	354	brne mmc_cocr_e
	355
	356	; Get trailing return value of R7 response
	357
	358	ldi temp2,4
	359	ldiw z,0x1a ;memory address of xl
	360	mmc_cocr1:
	361	rcall spi_rcvr
	362	st z+,temp
	363	dec temp2
	364	brne mmc_cocr1
	365	;z-flag =1
	366	mmc_cocr_e:
	367	ret
	368
9c15f366 L	369	;------------------------------------------------
	370	; Check if 1 sec timeout
	371	; return Z-Flag set, if timeout
	372
	373	mmc_timeout_1s:
	374	lds temp,delay_timer1
	375	tst temp
	376	brne mmc_ttex
825ecc9d	377	dec zh
9c15f366 L	378	breq mmc_ttex
	379	ldi temp,100
	380	sts delay_timer1,temp
	381	mmc_ttex:
	382	ret
	383
	384
	385	;------------------------------------------------
	386	; "Public" functions
	387	;------------------------------------------------
	388
	389	;------------------------------------------------
	390	; Initialize MMC/SD card
	391
	392	mmcInit:
	393	.if MMC_DEBUG
	394	printnewline
	395	printstring "mmcInit "
	396	.endif
	397	lds temp,mmcStat ;Set 'NO INIT' status
	398	sbr temp,MMCST_NOINIT
	399	sts mmcStat,temp
	400
	401	spi_clkslow
	402	ldi temp2,10
	403	mmci_lp:
	404	rcall spi_rcvr
	405	dec temp2 ;80 dummy clocks
	406	brne mmci_lp
	407
	408	ldi temp3,0 ;Card type
	409	ldi temp2,CMD0
	410	ldiw y,0
	411	movw x,y
	412	rcall mmcCmd ;Enter Idle state
	413	cpi temp,1
	414	breq mmci_1
	415	rjmp mmci_lend
	416	mmci_1:
825ecc9d	417	ldi zh,10 ;Initialization timeout of 1000 ms.
9c15f366 L	418	ldi temp,100
	419	sts delay_timer1,temp
	420	ldi temp2,CMD8
	421	ldiw y,0
	422	ldi xh,0x01
	423	ldi xl,0xAA
08716d4f L	424	ldi zl,1
	425	rcall mmcCmd_ocr
	426	brne mmci_sdv1 ;SDv2?
9c15f366	427
08716d4f L	428	cpi yl,0x01 ;ocr[2]
	429	brne mmci_sdv1
	430	cpi yh,0xAA ;ocr[3]
9c15f366 L	431	brne mmci_sdv1
	432
	433	; The card can work at vdd range of 2.7-3.6V.
	434	; Wait for leaving idle state (ACMD41 with HCS bit).
	435
	436	ldi temp2,ACMD41
	437	ldi yh,0x40
	438	ldi yl,0
	439	ldi xh,0
	440	ldi xl,0
	441	mmci_v2l2:
	442	rcall mmcCmd
	443	breq mmci_ccc
	444	rcall mmc_timeout_1s
	445	brne mmci_v2l2
	446	rjmp mmci_sdv2end
	447
	448	; Check CCS bit in the OCR
	449	mmci_ccc:
	450	ldi temp2,CMD58
	451	ldi yh,0
08716d4f L	452	ldi zl,0
	453	rcall mmcCmd_ocr
	454
9c15f366 L	455	brne mmci_sdv2end
9c15f366 L	456
9c15f366	457	sbr temp3,CT_SD2
08716d4f	458	sbrc xl,6
9c15f366 L	459	sbr temp3,CT_BLOCK
	460
	461	mmci_sdv2end:
	462	rjmp mmci_lend
	463
	464	; SDv1 or MMCv3
	465
	466	mmci_sdv1:
	467	ldi temp2,ACMD41
	468	ldiw y,0
	469	movw x,y
	470	rcall mmcCmd
	471	cpi temp,2
	472	brsh mmci_mmcv3
	473	sbr temp3,CT_SD1 ;SDv1
	474	ldi temp2,ACMD41
	475	rjmp mmci_v1_l
	476	mmci_mmcv3:
	477	sbr temp3,CT_MMC ;MMCv3
	478	ldi temp2,CMD1
	479
	480	; Wait for leaving idle state
	481	mmci_v1_l:
	482	rcall mmcCmd
	483	breq mmci_v1_2
	484	rcall mmc_timeout_1s
	485	brne mmci_v1_l
	486	rjmp mmci_lend ;Timeout
	487
	488	; Set R/W block length to 512
	489	mmci_v1_2:
	490	ldi temp2,CMD16
	491	ldiw x,512
	492	rcall mmcCmd
	493	breq mmci_lend
	494	ldi temp3,0
	495
	496	mmci_lend:
	497	sts mmcCardType,temp3
	498	rcall mmcDeselect
	499
	500	; Initialization succeded?
	501
	502	lds temp,mmcStat
	503	tst temp3
	504	breq mmci_lex
	505	cbr temp,MMCST_NOINIT ;Yes, clear 'NO INIT' status
	506	sts mmcStat,temp
	507	mmci_lex:
	508
	509	.if MMC_DEBUG
	510	printnewline
	511	printstring " CT: "
	512	push temp
	513	lds temp,mmcCardType
34527fc2	514	lcall printhex
9c15f366 L	515	pop temp
9c15f366 L	516	printstring " InitRes: "
34527fc2	517	lcall printhex
9c15f366 L	518	printstring " "
	519	.endif
	520
	521	spi_disable
	522	ret
	523
9c15f366	524	;--------------------------------------------------------------
34527fc2 L	525
	526	.equ MMC_RDOP = 0 ;Read Operation
	527	.equ MMC_RDWORD = 1 ;Read Word (FAT entry)
	528
	529	;--------------------------------------------------------------
9c15f366 L	530
9c15f366 L	531	mmcReadSect:
34527fc2	532
9c15f366 L	533	.if MMC_DEBUG > 1
	534	printnewline
	535	printstring "mmcRdSect "
	536	.endif
96a054ef	537	ldi temp,(1<<MMC_RDOP)
34527fc2 L	538	rjmp mmc_rw_common
	539
	540	mmcReadWord:
	541
	542	.if MMC_DEBUG > 1
	543	printnewline
	544	printstring "mmcRdWord "
	545	.endif
96a054ef	546	ldi temp,(1<<MMC_RDOP) \| (1<<MMC_RDWORD)
34527fc2 L	547	rjmp mmc_rw_common
	548
	549	mmcWriteSect:
	550
	551	.if MMC_DEBUG > 1
	552	printnewline
	553	printstring "mmcWrSect "
	554	.endif
96a054ef	555	ldi temp,0
9c15f366	556
34527fc2	557	mmc_rw_common:
96a054ef L	558	push temp3
96a054ef L	559	mov temp3,temp
34527fc2 L	560	lds temp,mmcStat
	561	ldi temp2,RES_NOTRDY
	562	sbrc temp,log2(MMCST_NOINIT)
	563	rjmp mmc_rwexit_2
9c15f366 L	564
	565	spi_clkfast
	566	lds temp,mmcCardType
	567	sbrs temp,log2(CT_BLOCK)
	568	rcall mul_yx_512 ;Convert to byte address (*512)
9c15f366	569
34527fc2 L	570	sbrc temp3,MMC_RDOP
	571	ldi temp2,CMD17
	572	sbrs temp3,MMC_RDOP
	573	ldi temp2,CMD24
	574	rcall mmcCmd
	575	breq mmc_rw_1
	576	rjmp mmc_rwexit_error
	577
	578	mmc_rw_1:
	579	ldiw y,hostbuf ;aarrrgh
	580	sbrs temp3,MMC_RDWORD
	581	movw z,y
	582	ldiw y,512
	583	sbrs temp3,MMC_RDOP
	584	rjmp mmc_wroper
	585
	586	;-------------------------------------------------------------------------------
9c15f366 L	587	; Receive a data packet from MMC
9c15f366 L	588
9c15f366 L	589	ldi temp,200 ;Wait for data packet in timeout of 200ms.
	590	sts delay_timer1,temp
	591	mmc_rcv_wl:
	592	rcall spi_rcvr
	593	cp temp,_255
	594	brne mmc_rcv_start
	595	lds _tmp0,delay_timer1
	596	cp _tmp0,_0
	597	brne mmc_rcv_wl
	598	.if MMC_DEBUG > 1
	599	printstring "TIMEOUT "
	600	rjmp mmc_rcv_dbg1
	601	.endif
	602
	603	mmc_rcv_start:
	604	.if MMC_DEBUG > 1
	605	cpi temp,0xFE ;If not valid data token,
	606	breq mmc_rcv_dbg1
	607	printstring "Token: "
34527fc2	608	lcall printhex
9c15f366 L	609	printstring " "
	610	mmc_rcv_dbg1:
	611	.endif
	612	cpi temp,0xFE ;If not valid data token,
34527fc2 L	613	breq mmc_rw_2
	614	rjmp mmc_rwexit_error
	615	mmc_rw_2:
	616
9c15f366	617	rcall spi_rcvr ;Shift in first byte.
4160d270 L	618	.if MMC_DEBUG > 3
4160d270 L	619	printnewline
34527fc2	620	lcall printhex
4160d270 L	621	printstring " "
4160d270 L	622	.endif
9c15f366	623	out SPDR,_255 ;Start shift in next byte.
9c15f366	624
34527fc2 L	625	sbrs temp3,MMC_RDWORD
34527fc2 L	626	rjmp mmc_rcv_readloop
92202636	627
34527fc2	628	; discard x-1 bytes
64219415	629
64219415 FZ	630	mmc_rcvw_rl:
64219415 FZ	631	sbiw yl,1
34527fc2	632	breq mmc_rcv_rlend
08716d4f L	633	cp zl,_0
08716d4f L	634	cpc zh,_0
92202636 L	635	breq mmc_rcvw_sto
	636
	637	sbiw zl,1
64219415	638	spi_waitm
08716d4f L	639	in temp,SPDR
08716d4f L	640	out SPDR,_255
64219415 FZ	641	rjmp mmc_rcvw_rl
64219415 FZ	642
34527fc2 L	643	; read next two bytes
34527fc2 L	644
92202636 L	645	mmc_rcvw_sto:
92202636 L	646	mov zl,temp
678fc0b0	647	spi_waitm
08716d4f L	648	in temp,SPDR
08716d4f L	649	out SPDR,_255
92202636 L	650	mov zh,temp
92202636 L	651
34527fc2 L	652	; discard the rest
34527fc2 L	653
678fc0b0 FZ	654	mmc_rcvw_rl2:
678fc0b0 FZ	655	sbiw yl,1
34527fc2	656	breq mmc_rcv_rlend
678fc0b0	657	spi_waitm
08716d4f L	658	in temp,SPDR
08716d4f L	659	out SPDR,_255
92202636	660	rjmp mmc_rcvw_rl2
9c15f366	661
34527fc2	662	; read sector, store in buffer
9c15f366	663
34527fc2 L	664	mmc_rcv_readloop:
	665	sbiw yl,1
	666	breq mmc_rcv_rle
	667	st z+,temp
	668	spi_waitm
	669	in temp,SPDR
	670	.if MMC_DEBUG > 3
	671	lcall printhex
	672	printstring " "
	673	.endif
	674	out SPDR,_255
	675	rjmp mmc_rcv_readloop
	676
	677	mmc_rcv_rle:
	678	st z+,temp ;Store last byte in buffer
	679	mmc_rcv_rlend:
	680	.if MMC_DEBUG > 3
9c15f366	681	printnewline
9c15f366	682	.endif
34527fc2 L	683	rcall spi_wait ;while SPI module shifts in crc part1.
34527fc2 L	684	rcall spi_rcvr ;Read second crc.
9c15f366	685
34527fc2 L	686	ldi temp2,RES_OK ;Return success
34527fc2 L	687	rjmp mmc_rwexit
9c15f366	688
9c15f366	689
34527fc2	690	;-------------------------------------------------------------------------------
9c15f366 L	691	; Send a data packet to MMC
9c15f366 L	692
34527fc2 L	693	mmc_wroper:
34527fc2 L	694
9c15f366 L	695	.if MMC_DEBUG > 2
	696	; printnewline
	697	printstring "mmcXMIT "
	698	.endif
	699	rcall mmcWaitReady
34527fc2	700	breq mmc_rwexit_error
9c15f366 L	701
	702	ldi temp,0xFE ;Data token
	703	out SPDR,temp
9c15f366 L	704	mmc_x_loop:
	705	ld temp,z+
	706	spi_waitm
	707	out SPDR,temp
	708	sbiw yl,1
	709	brne mmc_x_loop
	710
	711	rcall spi_wait
	712	ldi temp,0xFF ;dummy crc
	713	rcall spi_xmit
	714	rcall spi_xmit
	715	rcall spi_rcvr
	716	.if MMC_DEBUG > 2
	717	printstring "XMITRes: "
34527fc2	718	lcall printhex
9c15f366 L	719	printstring " "
	720	.endif
	721	andi temp,0x1F ;If not accepted, return with error
	722	cpi temp,0x05
	723	ldi temp2,RES_OK ;Return success
34527fc2	724	breq mmc_rwexit
9c15f366	725
34527fc2 L	726	mmc_rwexit_error:
	727	ldi temp2,RES_ERROR
	728	mmc_rwexit:
9c15f366 L	729	rcall mmcDeselect
9c15f366 L	730	spi_disable
34527fc2	731	mmc_rwexit_2:
9c15f366	732	mov temp,temp2
34527fc2	733
9c15f366	734	.if MMC_DEBUG > 1
34527fc2 L	735	sbrc temp3,MMC_RDOP
	736	rjmp mmc_dbg_rder
	737
	738	printstring "WrSectRes: "
	739	rjmp mmc_dbg_rwerex
	740
	741	mmc_dbg_rder:
	742	sbrc temp3,MMC_RDWORD
	743	rjmp mmc_dbg_rdwder
	744	printstring "RdSectRes: "
	745	rjmp mmc_dbg_rwerex
	746
	747	mmc_dbg_rdwder:
	748	printstring "RdWordRes: "
	749	mmc_dbg_rwerex:
	750	lcall printhex
9c15f366 L	751	printstring " "
9c15f366 L	752	.endif
96a054ef	753	pop temp3
9c15f366 L	754	ret
	755
	756	;--------------------------------------------------------------
	757	; vim:set ts=8 noet nowrap
	758