xref: /OK3568_Linux_fs/u-boot/doc/README.atmel_mci (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunHow to use SD/MMC cards with Atmel SoCs having MCI hardware
2*4882a593Smuzhiyun-----------------------------------------------------------
3*4882a593Smuzhiyun2010-08-16 Reinhard Meyer <reinhard.meyer@emk-elektronik.de>
4*4882a593Smuzhiyun
5*4882a593SmuzhiyunThis is a new approach to use Atmel MCI hardware with the
6*4882a593Smuzhiyungeneral MMC framework. Therefore it benefits from that
7*4882a593Smuzhiyunframework's abilities to handle SDHC Cards and the ability
8*4882a593Smuzhiyunto write blocks.
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun- AT91SAM9XE512 (tested, will definitely work with XE128 and XE256)
11*4882a593Smuzhiyun- AT91SAM9260 (not tested, but MCI is to AT91SAM9XE)
12*4882a593Smuzhiyun- AT91SAM9G20 (not tested, should work)
13*4882a593Smuzhiyun
14*4882a593SmuzhiyunIt should work with all other ATMEL devices that have MCI.
15*4882a593Smuzhiyun
16*4882a593SmuzhiyunThe generic driver does NOT assign port pins to the MCI block
17*4882a593Smuzhiyunnor does it start the MCI clock. This has to be handled in a
18*4882a593Smuzhiyunboard/SoC specific manner before the driver is initialized:
19*4882a593Smuzhiyun
20*4882a593Smuzhiyunexample: this is added to at91sam9260_devices.c:
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun#if defined(CONFIG_GENERIC_ATMEL_MCI)
23*4882a593Smuzhiyunvoid at91_mci_hw_init(void)
24*4882a593Smuzhiyun{
25*4882a593Smuzhiyun	at91_set_a_periph(AT91_PIO_PORTA, 8, PUP);	/* MCCK */
26*4882a593Smuzhiyun#if defined(CONFIG_ATMEL_MCI_PORTB)
27*4882a593Smuzhiyun	at91_set_b_periph(AT91_PIO_PORTA, 1, PUP);	/* MCCDB */
28*4882a593Smuzhiyun	at91_set_b_periph(AT91_PIO_PORTA, 0, PUP);	/* MCDB0 */
29*4882a593Smuzhiyun	at91_set_b_periph(AT91_PIO_PORTA, 5, PUP);	/* MCDB1 */
30*4882a593Smuzhiyun	at91_set_b_periph(AT91_PIO_PORTA, 4, PUP);	/* MCDB2 */
31*4882a593Smuzhiyun	at91_set_b_periph(AT91_PIO_PORTA, 3, PUP);	/* MCDB3 */
32*4882a593Smuzhiyun#else
33*4882a593Smuzhiyun	at91_set_a_periph(AT91_PIO_PORTA, 7, PUP);	/* MCCDA */
34*4882a593Smuzhiyun	at91_set_a_periph(AT91_PIO_PORTA, 6, PUP);	/* MCDA0 */
35*4882a593Smuzhiyun	at91_set_a_periph(AT91_PIO_PORTA, 9, PUP);	/* MCDA1 */
36*4882a593Smuzhiyun	at91_set_a_periph(AT91_PIO_PORTA, 10, PUP);	/* MCDA2 */
37*4882a593Smuzhiyun	at91_set_a_periph(AT91_PIO_PORTA, 11, PUP);	/* MCDA3 */
38*4882a593Smuzhiyun#endif
39*4882a593Smuzhiyun}
40*4882a593Smuzhiyun#endif
41*4882a593Smuzhiyun
42*4882a593Smuzhiyunthe board specific file need added:
43*4882a593Smuzhiyun...
44*4882a593Smuzhiyun#ifdef CONFIG_GENERIC_ATMEL_MCI
45*4882a593Smuzhiyun# include <mmc.h>
46*4882a593Smuzhiyun#endif
47*4882a593Smuzhiyun...
48*4882a593Smuzhiyun#ifdef CONFIG_GENERIC_ATMEL_MCI
49*4882a593Smuzhiyun/* this is a weak define that we are overriding */
50*4882a593Smuzhiyunint board_mmc_init(bd_t *bd)
51*4882a593Smuzhiyun{
52*4882a593Smuzhiyun	/* Enable clock */
53*4882a593Smuzhiyun	at91_sys_write(AT91_PMC_PCER, 1 << AT91SAM9260_ID_MCI);
54*4882a593Smuzhiyun	at91_mci_hw_init();
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun	/* This calls the atmel_mci_init in gen_atmel_mci.c */
57*4882a593Smuzhiyun	return atmel_mci_init((void *)AT91_BASE_MCI);
58*4882a593Smuzhiyun}
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun/* this is a weak define that we are overriding */
61*4882a593Smuzhiyunint board_mmc_getcd(struct mmc *mmc)
62*4882a593Smuzhiyun{
63*4882a593Smuzhiyun	return !at91_get_gpio_value(CONFIG_SYS_MMC_CD_PIN);
64*4882a593Smuzhiyun}
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun#endif
67*4882a593Smuzhiyun
68*4882a593Smuzhiyunand the board definition files needs:
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun/* SD/MMC card */
71*4882a593Smuzhiyun#define CONFIG_GENERIC_ATMEL_MCI	1
72*4882a593Smuzhiyun#define CONFIG_ATMEL_MCI_PORTB		1	/* Atmel XE-EK uses port B */
73*4882a593Smuzhiyun#define CONFIG_SYS_MMC_CD_PIN		AT91_PIN_PC9
74*4882a593Smuzhiyun#define CONFIG_CMD_MMC			1
75