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osd-contiki/dev/disk/mmc/mmc.c
Benoît Thébaudeau faf22609f4 disk: Add SD/MMC driver 
Only SPI is supported.

Signed-off-by: Benoît Thébaudeau <benoit@wsystem.com>
2016-11-27 22:50:42 +01:00

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/*
* Copyright (c) 2016, Benoît Thébaudeau <benoit@wsystem.com>
* All rights reserved.
*
* Based on the FatFs Module STM32 Sample Project,
* Copyright (c) 2014, ChaN
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/**
* \addtogroup mmc
* @{
*
* \file
* Implementation of the SD/MMC device driver.
*/
#include <stddef.h>
#include <stdint.h>
#include "contiki.h"
#include "sys/clock.h"
#include "sys/rtimer.h"
#include "dev/watchdog.h"
#include "mmc-arch.h"
#include "mmc.h"
/* Data read/write block length */
#define BLOCK_LEN 512
/*
* Logical sector size exposed to the disk API, not to be confused with the SDSC
* sector size, which is the size of an erasable sector
*/
#define SECTOR_SIZE BLOCK_LEN
/* Clock frequency in card identification mode: fOD <= 400 kHz */
#define CLOCK_FREQ_CARD_ID_MODE 400000
/*
* Clock frequency in data transfer mode: fPP <= 20 MHz, limited by the
* backward-compatible MMC interface timings
*/
#define CLOCK_FREQ_DATA_XFER_MODE 20000000
/* SPI-mode command list */
#define CMD0 0 /* GO_IDLE_STATE */
#define CMD1 1 /* SEND_OP_COND */
#define CMD8 8 /* SEND_IF_COND */
#define CMD8_VHS_2_7_3_6 0x1
#define CMD8_ARG(vhs, check_pattern) ((vhs) << 8 | (check_pattern))
#define CMD8_ECHO_MASK 0x00000fff
#define CMD9 9 /* SEND_CSD */
#define CMD10 10 /* SEND_CID */
#define CMD12 12 /* STOP_TRANSMISSION */
#define CMD13 13 /* SEND_STATUS */
#define CMD16 16 /* SET_BLOCKLEN */
#define CMD17 17 /* READ_SINGLE_BLOCK */
#define CMD18 18 /* READ_MULTIPLE_BLOCK */
#define CMD23 23 /* SET_BLOCK_COUNT */
#define CMD24 24 /* WRITE_BLOCK */
#define CMD25 25 /* WRITE_MULTIPLE_BLOCK */
#define CMD32 32 /* ERASE_WR_BLK_START */
#define CMD33 33 /* ERASE_WR_BLK_END */
#define CMD38 38 /* ERASE */
#define CMD55 55 /* APP_CMD */
#define CMD58 58 /* READ_OCR */
#define ACMD 0x80 /* Application-specific command */
#define ACMD13 (ACMD | 13) /* SD_STATUS */
#define ACMD23 (ACMD | 23) /* SET_WR_BLK_ERASE_COUNT */
#define ACMD41 (ACMD | 41) /* SD_APP_OP_COND */
#define ACMD41_HCS (1 << 30)
#define CMD_TX 0x40 /* Command transmission bit */
#define R1_MSB 0x00
#define R1_SUCCESS 0x00
#define R1_IDLE_STATE (1 << 0)
#define R1_ERASE_RESET (1 << 1)
#define R1_ILLEGAL_COMMAND (1 << 2)
#define R1_COM_CRC_ERROR (1 << 3)
#define R1_ERASE_SEQUENCE_ERROR (1 << 4)
#define R1_ADDRESS_ERROR (1 << 5)
#define R1_PARAMETER_ERROR (1 << 6)
#define TOK_DATA_RESP_MASK 0x1f
#define TOK_DATA_RESP_ACCEPTED 0x05
#define TOK_DATA_RESP_CRC_ERROR 0x0b
#define TOK_DATA_RESP_WR_ERROR 0x0d
#define TOK_RD_SINGLE_WR_START_BLOCK 0xfe
#define TOK_MULTI_WR_START_BLOCK 0xfc
#define TOK_MULTI_WR_STOP_TRAN 0xfd
/* The SD Status is one data block of 512 bits. */
#define SD_STATUS_SIZE (512 / 8)
#define SD_STATUS_AU_SIZE(sd_status) ((sd_status)[10] >> 4)
#define OCR_CCS (1 << 30)
#define CSD_SIZE 16
#define CSD_STRUCTURE(csd) ((csd)[0] >> 6)
#define CSD_STRUCTURE_SD_V1_0 0
#define CSD_STRUCTURE_SD_V2_0 1
#define CSD_SD_V1_0_READ_BL_LEN(csd) ((csd)[5] & 0x0f)
#define CSD_SD_V1_0_BLOCK_LEN(csd) (1ull << CSD_SD_V1_0_READ_BL_LEN(csd))
#define CSD_SD_V1_0_C_SIZE(csd) \
(((csd)[6] & 0x03) << 10 | (csd)[7] << 2 | (csd)[8] >> 6)
#define CSD_SD_V1_0_C_SIZE_MULT(csd) \
(((csd)[9] & 0x03) << 1 | (csd)[10] >> 7)
#define CSD_SD_V1_0_MULT(csd) \
(1 << (CSD_SD_V1_0_C_SIZE_MULT(csd) + 2))
#define CSD_SD_V1_0_BLOCKNR(csd) \
(((uint32_t)CSD_SD_V1_0_C_SIZE(csd) + 1) * CSD_SD_V1_0_MULT(csd))
#define CSD_SD_V1_0_CAPACITY(csd) \
(CSD_SD_V1_0_BLOCKNR(csd) * CSD_SD_V1_0_BLOCK_LEN(csd))
#define CSD_SD_V1_0_SECTOR_SIZE(csd) \
(((csd)[10] & 0x3f) << 1 | (csd)[11] >> 7)
#define CSD_SD_V1_0_WRITE_BL_LEN(csd) \
(((csd)[12] & 0x03) << 2 | (csd)[13] >> 6)
#define CSD_SD_V2_0_C_SIZE(csd) \
(((csd)[7] & 0x3f) << 16 | (csd)[8] << 8 | (csd)[9])
#define CSD_SD_V2_0_CAPACITY(csd) \
(((uint64_t)CSD_SD_V2_0_C_SIZE(csd) + 1) << 19)
#define CSD_MMC_ERASE_GRP_SIZE(csd) (((csd)[10] & 0x7c) >> 2)
#define CSD_MMC_ERASE_GRP_MULT(csd) \
(((csd)[10] & 0x03) << 3 | (csd)[11] >> 5)
#define CSD_MMC_WRITE_BL_LEN(csd) \
(((csd)[12] & 0x03) << 2 | (csd)[13] >> 6)
typedef enum {
CARD_TYPE_MMC = 0x01, /* MMC v3 */
CARD_TYPE_SD1 = 0x02, /* SD v1 */
CARD_TYPE_SD2 = 0x04, /* SD v2 */
CARD_TYPE_SD = CARD_TYPE_SD1 | CARD_TYPE_SD2, /* SD */
CARD_TYPE_BLOCK = 0x08 /* Block addressing */
} card_type_t;
static struct mmc_priv {
uint8_t status;
uint8_t card_type;
} mmc_priv[MMC_CONF_DEV_COUNT];
/*----------------------------------------------------------------------------*/
static uint8_t
mmc_spi_xchg(uint8_t dev, uint8_t tx_byte)
{
uint8_t rx_byte;
mmc_arch_spi_xfer(dev, &tx_byte, 1, &rx_byte, 1);
return rx_byte;
}
/*----------------------------------------------------------------------------*/
static void
mmc_spi_tx(uint8_t dev, const void *buf, size_t cnt)
{
mmc_arch_spi_xfer(dev, buf, cnt, NULL, 0);
}
/*----------------------------------------------------------------------------*/
static void
mmc_spi_rx(uint8_t dev, void *buf, size_t cnt)
{
mmc_arch_spi_xfer(dev, NULL, 0, buf, cnt);
}
/*----------------------------------------------------------------------------*/
static bool
mmc_wait_ready(uint8_t dev, uint16_t timeout_ms)
{
rtimer_clock_t timeout_end =
RTIMER_NOW() + ((uint32_t)timeout_ms * RTIMER_SECOND + 999) / 1000;
uint8_t rx_byte;
do {
rx_byte = mmc_spi_xchg(dev, 0xff);
watchdog_periodic();
} while(rx_byte != 0xff && RTIMER_CLOCK_LT(RTIMER_NOW(), timeout_end));
return rx_byte == 0xff;
}
/*----------------------------------------------------------------------------*/
static bool
mmc_select(uint8_t dev, bool sel)
{
mmc_arch_spi_select(dev, sel);
mmc_spi_xchg(dev, 0xff); /* Dummy clock (force D0) */
if(sel && !mmc_wait_ready(dev, 500)) {
mmc_select(dev, false);
return false;
}
return true;
}
/*----------------------------------------------------------------------------*/
static uint8_t
mmc_send_cmd(uint8_t dev, uint8_t cmd, uint32_t arg)
{
uint8_t resp, n;
/* Send a CMD55 prior to a ACMD<n>. */
if(cmd & ACMD) {
cmd &= ~ACMD;
resp = mmc_send_cmd(dev, CMD55, 0);
if(resp != R1_SUCCESS && resp != R1_IDLE_STATE) {
return resp;
}
}
/*
* Select the card and wait for ready, except to stop a multiple-block read.
*/
if(cmd != CMD12) {
mmc_select(dev, false);
if(!mmc_select(dev, true)) {
return 0xff;
}
}
/* Send the command packet. */
mmc_spi_xchg(dev, CMD_TX | cmd); /* Start & tx bits, cmd index */
mmc_spi_xchg(dev, arg >> 24); /* Argument[31..24] */
mmc_spi_xchg(dev, arg >> 16); /* Argument[23..16] */
mmc_spi_xchg(dev, arg >> 8); /* Argument[15..8] */
mmc_spi_xchg(dev, arg); /* Argument[7..0] */
switch(cmd) {
case CMD0:
n = 0x95; /* CMD0(0) CRC7, end bit */
break;
case CMD8:
n = 0x87; /* CMD8(0x1aa) CRC7, end bit */
break;
default:
n = 0x01; /* Dummy CRC7, end bit */
break;
}
mmc_spi_xchg(dev, n);
/* Receive the command response. */
if(cmd == CMD12) {
mmc_spi_xchg(dev, 0xff); /* Discard following byte if CMD12. */
}
/* Wait for the response (max. 10 bytes). */
n = 10;
do {
resp = mmc_spi_xchg(dev, 0xff);
} while((resp & 0x80) != R1_MSB && --n);
return resp;
}
/*----------------------------------------------------------------------------*/
static bool
mmc_tx_block(uint8_t dev, const void *buf, uint8_t token)
{
uint8_t resp;
if(!mmc_wait_ready(dev, 500)) {
return false;
}
mmc_spi_xchg(dev, token);
if(token != TOK_MULTI_WR_STOP_TRAN) {
mmc_spi_tx(dev, buf, BLOCK_LEN);
mmc_spi_xchg(dev, 0xff); /* Dummy CRC */
mmc_spi_xchg(dev, 0xff);
resp = mmc_spi_xchg(dev, 0xff);
if((resp & TOK_DATA_RESP_MASK) != TOK_DATA_RESP_ACCEPTED) {
return false;
}
}
return true;
}
/*----------------------------------------------------------------------------*/
static bool
mmc_rx(uint8_t dev, void *buf, size_t cnt)
{
rtimer_clock_t timeout_end =
RTIMER_NOW() + (200ul * RTIMER_SECOND + 999) / 1000;
uint8_t token;
do {
token = mmc_spi_xchg(dev, 0xff);
watchdog_periodic();
} while(token == 0xff && RTIMER_CLOCK_LT(RTIMER_NOW(), timeout_end));
if(token != TOK_RD_SINGLE_WR_START_BLOCK) {
return false;
}
mmc_spi_rx(dev, buf, cnt);
mmc_spi_xchg(dev, 0xff); /* Discard CRC. */
mmc_spi_xchg(dev, 0xff);
return true;
}
/*----------------------------------------------------------------------------*/
void
mmc_arch_cd_changed_callback(uint8_t dev, bool cd)
{
uint8_t status;
if(dev >= MMC_CONF_DEV_COUNT) {
return;
}
if(cd) {
status = DISK_STATUS_DISK;
if(!mmc_arch_get_wp(dev)) {
status |= DISK_STATUS_WRITABLE;
}
} else {
status = 0;
}
mmc_priv[dev].status = status;
}
/*----------------------------------------------------------------------------*/
static disk_status_t
mmc_status(uint8_t dev)
{
bool cd;
struct mmc_priv *priv;
if(dev >= MMC_CONF_DEV_COUNT) {
return DISK_RESULT_INVALID_ARG;
}
cd = mmc_arch_get_cd(dev);
priv = &mmc_priv[dev];
if(cd == !(priv->status & DISK_STATUS_DISK)) {
mmc_arch_cd_changed_callback(dev, cd);
}
return priv->status;
}
/*----------------------------------------------------------------------------*/
static disk_status_t
mmc_initialize(uint8_t dev)
{
disk_status_t status;
uint8_t n, cmd;
card_type_t card_type;
rtimer_clock_t timeout_end;
uint32_t arg, resp, ocr;
struct mmc_priv *priv;
if(dev >= MMC_CONF_DEV_COUNT) {
return DISK_RESULT_INVALID_ARG;
}
status = mmc_status(dev);
if(!(status & DISK_STATUS_DISK)) {
return status;
}
mmc_arch_spi_select(dev, false);
clock_delay_usec(10000);
mmc_arch_spi_set_clock_freq(dev, CLOCK_FREQ_CARD_ID_MODE);
for(n = 10; n; n--) {
mmc_spi_xchg(dev, 0xff); /* Generate 80 dummy clock cycles. */
}
card_type = 0;
if(mmc_send_cmd(dev, CMD0, 0) == R1_IDLE_STATE) {
timeout_end = RTIMER_NOW() + RTIMER_SECOND;
arg = CMD8_ARG(CMD8_VHS_2_7_3_6, 0xaa); /* Arbitrary check pattern */
if(mmc_send_cmd(dev, CMD8, arg) == R1_IDLE_STATE) { /* SD v2? */
resp = 0;
for(n = 4; n; n--) {
resp = resp << 8 | mmc_spi_xchg(dev, 0xff);
}
/* Does the card support 2.7 V - 3.6 V? */
if((arg & CMD8_ECHO_MASK) == (resp & CMD8_ECHO_MASK)) {
/* Wait for end of initialization. */
while(RTIMER_CLOCK_LT(RTIMER_NOW(), timeout_end) &&
mmc_send_cmd(dev, ACMD41, ACMD41_HCS) != R1_SUCCESS) {
watchdog_periodic();
}
if(RTIMER_CLOCK_LT(RTIMER_NOW(), timeout_end) &&
mmc_send_cmd(dev, CMD58, 0) == R1_SUCCESS) { /* Read OCR. */
ocr = 0;
for(n = 4; n; n--) {
ocr = ocr << 8 | mmc_spi_xchg(dev, 0xff);
}
card_type = CARD_TYPE_SD2;
if(ocr & OCR_CCS) {
card_type |= CARD_TYPE_BLOCK;
}
}
}
} else { /* Not SD v2 */
resp = mmc_send_cmd(dev, ACMD41, 0);
if(resp == R1_SUCCESS || resp == R1_IDLE_STATE) { /* SD v1 or MMC? */
card_type = CARD_TYPE_SD1;
cmd = ACMD41;
} else {
card_type = CARD_TYPE_MMC;
cmd = CMD1;
}
/* Wait for end of initialization. */
while(RTIMER_CLOCK_LT(RTIMER_NOW(), timeout_end) &&
mmc_send_cmd(dev, cmd, 0) != R1_SUCCESS) {
watchdog_periodic();
}
/* Set block length. */
if(!RTIMER_CLOCK_LT(RTIMER_NOW(), timeout_end) ||
mmc_send_cmd(dev, CMD16, BLOCK_LEN) != R1_SUCCESS) {
card_type = 0;
}
}
}
priv = &mmc_priv[dev];
priv->card_type = card_type;
mmc_select(dev, false);
status = priv->status;
if(status & DISK_STATUS_DISK && card_type) { /* OK */
mmc_arch_spi_set_clock_freq(dev, CLOCK_FREQ_DATA_XFER_MODE);
status |= DISK_STATUS_INIT;
} else { /* Failed */
status &= ~DISK_STATUS_INIT;
}
priv->status = status;
return status;
}
/*----------------------------------------------------------------------------*/
static disk_result_t
mmc_read(uint8_t dev, void *buff, uint32_t sector, uint32_t count)
{
if(dev >= MMC_CONF_DEV_COUNT || !count) {
return DISK_RESULT_INVALID_ARG;
}
if(!(mmc_status(dev) & DISK_STATUS_INIT)) {
return DISK_RESULT_NO_INIT;
}
if(!(mmc_priv[dev].card_type & CARD_TYPE_BLOCK)) {
sector *= SECTOR_SIZE;
}
if(count == 1) {
if(mmc_send_cmd(dev, CMD17, sector) == R1_SUCCESS &&
mmc_rx(dev, buff, SECTOR_SIZE)) {
count = 0;
}
} else if(mmc_send_cmd(dev, CMD18, sector) == R1_SUCCESS) {
do {
if(!mmc_rx(dev, buff, SECTOR_SIZE)) {
break;
}
buff = (uint8_t *)buff + SECTOR_SIZE;
watchdog_periodic();
} while(--count);
mmc_send_cmd(dev, CMD12, 0); /* Stop transmission. */
}
mmc_select(dev, false);
return count ? DISK_RESULT_IO_ERROR : DISK_RESULT_OK;
}
/*----------------------------------------------------------------------------*/
static disk_result_t
mmc_write(uint8_t dev, const void *buff, uint32_t sector, uint32_t count)
{
disk_status_t status;
card_type_t card_type;
if(dev >= MMC_CONF_DEV_COUNT || !count) {
return DISK_RESULT_INVALID_ARG;
}
status = mmc_status(dev);
if(!(status & DISK_STATUS_INIT)) {
return DISK_RESULT_NO_INIT;
}
if(!(status & DISK_STATUS_WRITABLE)) {
return DISK_RESULT_WR_PROTECTED;
}
card_type = mmc_priv[dev].card_type;
if(!(card_type & CARD_TYPE_BLOCK)) {
sector *= SECTOR_SIZE;
}
if(count == 1) {
if(mmc_send_cmd(dev, CMD24, sector) == R1_SUCCESS &&
mmc_tx_block(dev, buff, TOK_RD_SINGLE_WR_START_BLOCK)) {
count = 0;
}
} else {
if(card_type & CARD_TYPE_SD) {
mmc_send_cmd(dev, ACMD23, count);
}
if(mmc_send_cmd(dev, CMD25, sector) == R1_SUCCESS) {
do {
if(!mmc_tx_block(dev, buff, TOK_MULTI_WR_START_BLOCK)) {
break;
}
buff = (uint8_t *)buff + BLOCK_LEN;
watchdog_periodic();
} while(--count);
if(!mmc_tx_block(dev, NULL, TOK_MULTI_WR_STOP_TRAN)) {
count = 1;
}
}
}
mmc_select(dev, false);
return count ? DISK_RESULT_IO_ERROR : DISK_RESULT_OK;
}
/*----------------------------------------------------------------------------*/
static disk_result_t
mmc_ioctl(uint8_t dev, uint8_t cmd, void *buff)
{
card_type_t card_type;
disk_result_t res;
uint8_t csd[CSD_SIZE], sd_status[SD_STATUS_SIZE], au_size;
uint64_t capacity;
uint32_t block_size;
static const uint8_t AU_TO_BLOCK_SIZE[] = {12, 16, 24, 32, 64};
if(dev >= MMC_CONF_DEV_COUNT) {
return DISK_RESULT_INVALID_ARG;
}
if(!(mmc_status(dev) & DISK_STATUS_INIT)) {
return DISK_RESULT_NO_INIT;
}
card_type = mmc_priv[dev].card_type;
res = DISK_RESULT_IO_ERROR;
switch(cmd) {
case DISK_IOCTL_CTRL_SYNC:
if(mmc_select(dev, true)) {
res = DISK_RESULT_OK;
}
break;
case DISK_IOCTL_GET_SECTOR_COUNT:
if(mmc_send_cmd(dev, CMD9, 0) == R1_SUCCESS && mmc_rx(dev, csd, CSD_SIZE)) {
capacity = CSD_STRUCTURE(csd) == CSD_STRUCTURE_SD_V2_0 ?
CSD_SD_V2_0_CAPACITY(csd) : CSD_SD_V1_0_CAPACITY(csd);
*(uint32_t *)buff = capacity / SECTOR_SIZE;
res = DISK_RESULT_OK;
}
break;
case DISK_IOCTL_GET_SECTOR_SIZE:
*(uint16_t *)buff = SECTOR_SIZE;
res = DISK_RESULT_OK;
break;
case DISK_IOCTL_GET_BLOCK_SIZE:
if(card_type & CARD_TYPE_SD2) {
if(mmc_send_cmd(dev, ACMD13, 0) == R1_SUCCESS) { /* Read SD status. */
mmc_spi_xchg(dev, 0xff);
if(mmc_rx(dev, sd_status, SD_STATUS_SIZE)) {
au_size = SD_STATUS_AU_SIZE(sd_status);
if(au_size) {
block_size = au_size <= 0xa ? 8192ull << au_size :
(uint32_t)AU_TO_BLOCK_SIZE[au_size - 0xb] << 20;
*(uint32_t *)buff = block_size / SECTOR_SIZE;
res = DISK_RESULT_OK;
}
}
}
} else if(mmc_send_cmd(dev, CMD9, 0) == R1_SUCCESS &&
mmc_rx(dev, csd, CSD_SIZE)) {
if(card_type & CARD_TYPE_SD1) {
block_size = (uint32_t)(CSD_SD_V1_0_SECTOR_SIZE(csd) + 1) <<
CSD_SD_V1_0_WRITE_BL_LEN(csd);
} else { /* MMC */
block_size = (uint32_t)(CSD_MMC_ERASE_GRP_SIZE(csd) + 1) *
(CSD_MMC_ERASE_GRP_MULT(csd) + 1) <<
CSD_MMC_WRITE_BL_LEN(csd);
}
*(uint32_t *)buff = block_size / SECTOR_SIZE;
res = DISK_RESULT_OK;
}
break;
default:
res = DISK_RESULT_INVALID_ARG;
break;
}
mmc_select(dev, false);
return res;
}
/*----------------------------------------------------------------------------*/
const struct disk_driver mmc_driver = {
.status = mmc_status,
.initialize = mmc_initialize,
.read = mmc_read,
.write = mmc_write,
.ioctl = mmc_ioctl
};
/*----------------------------------------------------------------------------*/
/** @} */
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