rockbox/firmware/target/arm/tms320dm320/sdmmc-dm320.c
Tomasz Moń 8de163b8ae
Sansa Connect: Fix reported CPU frequency
Make frequency related comments accurate. Disable UART0 clock.

Change-Id: I224a3d6656ad53165dcff68ed716fa2c6863240d
2021-07-09 14:16:05 +02:00

906 lines
22 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id: $
*
* Copyright (C) 2011 by Tomasz Moń
*
* This program 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 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "system.h"
#include <string.h>
#include "gcc_extensions.h"
#include "panic.h"
#include "dma-target.h"
#include "ata_idle_notify.h"
//#define SD_DEBUG
#ifdef SD_DEBUG
#include "lcd-target.h"
#include "lcd.h"
#include "font.h"
#ifdef BOOTLOADER
#include "common.h"
#else
#include "debug.h"
#endif
#endif
#include "sdmmc.h"
#include "system-target.h"
#include "storage.h"
/* The configuration method is not very flexible. */
#define CARD_NUM_SLOT 1
#define NUM_CARDS 2
#define EC_OK 0
#define EC_FAILED 1
#define EC_NOCARD 2
#define EC_WAIT_STATE_FAILED 3
#define EC_POWER_UP 4
#define EC_FIFO_WR_EMPTY 5
#define EC_FIFO_WR_DONE 6
#define EC_TRAN_READ_ENTRY 7
#define EC_TRAN_READ_EXIT 8
#define EC_TRAN_WRITE_ENTRY 9
#define EC_TRAN_WRITE_EXIT 10
#define EC_COMMAND 11
#define EC_WRITE_PROTECT 12
#define EC_DATA_TIMEOUT 13
#define EC_RESP_TIMEOUT 14
#define EC_CRC_ERROR 15
#define NUM_EC 16
#define MIN_YIELD_PERIOD 5
#define UNALIGNED_NUM_SECTORS 10
#define MAX_TRANSFER_ERRORS 10
#define BLOCKS_PER_BANK 0x7A7800
/* command flags for send_cmd */
#define SDHC_RESP_FMT_MASK 0x0600
#define SDHC_RESP_FMT_NONE 0x0000
#define SDHC_RESP_FMT_1 0x0200
#define SDHC_RESP_FMT_2 0x0400
#define SDHC_RESP_FMT_3 0x0600
#define INITIAL_CLK 312500 /* Initial clock */
#define SD_CLK 24000000 /* Clock for SD cards */
#define MMC_CLK 15000000 /* Clock for MMC cards */
#ifdef SD_DEBUG
#ifdef BOOTLOADER
#define dbgprintf printf
#else
#define dbgprintf DEBUGF
#endif
#else
#define dbgprintf(...)
#endif
struct sd_card_status
{
int retry;
int retry_max;
};
/** static, private data **/
/* for compatibility */
static long last_disk_activity = -1;
static bool initialized = false;
static bool sd_enabled = false;
static long next_yield = 0;
static tCardInfo card_info [NUM_CARDS];
static tCardInfo *currcard;
static struct sd_card_status sd_status[NUM_CARDS] =
{
#if NUM_CARDS > 1
{0, 10},
#endif
{0, 10}
};
/* Shoot for around 75% usage */
static struct mutex sd_mtx SHAREDBSS_ATTR;
static struct semaphore data_done SHAREDBSS_ATTR;
static volatile unsigned int transfer_error[NUM_DRIVES];
/* align on cache line size */
static unsigned char aligned_buffer[UNALIGNED_NUM_SECTORS * SD_BLOCK_SIZE]
__attribute__((aligned(32)));
static void sd_card_mux(int card_no)
{
#ifdef HAVE_MULTIDRIVE
#ifdef SANSA_CONNECT
/* GIO6 - select Card; GIO5 - select iNAND (both active low) */
if (card_no == CARD_NUM_SLOT)
{
IO_GIO_BITSET0 = (1 << 5); /* deselect iNAND (GIO5) */
IO_GIO_BITCLR0 = (1 << 6); /* select card (GIO6) */
}
else
{
IO_GIO_BITSET0 = (1 << 6); /* deselect card (GIO6) */
IO_GIO_BITCLR0 = (1 << 5); /* select iNAND (GIO5) */
}
#else /* Different players */
(void)card_no;
#endif
#else /* No multidrive */
(void)card_no;
#endif
}
static inline void enable_controller(bool on)
{
sd_enabled = on;
}
void sd_enable(bool on)
{
mutex_lock(&sd_mtx);
enable_controller(on);
mutex_unlock(&sd_mtx);
}
/* sets clock rate just like OF does */
static void sd_set_clock_rate(unsigned long rate)
{
unsigned char rate_val = 0;
if (rate == INITIAL_CLK)
{
rate_val = 0x3B;
}
else if (rate > INITIAL_CLK)
{
rate_val = 0;
}
else
{
rate_val = 0xFF;
}
IO_MMC_MEM_CLK_CONTROL = (IO_MMC_MEM_CLK_CONTROL & 0xFF00) | rate_val;
}
static int sd_poll_status(int st_reg_num, volatile unsigned int flag)
{
unsigned int status;
unsigned int status1;
bool done;
do
{
long time = current_tick;
if (TIME_AFTER(time, next_yield))
{
long ty = current_tick;
yield();
next_yield = ty + MIN_YIELD_PERIOD;
}
status = IO_MMC_STATUS0;
status1 = IO_MMC_STATUS1;
if (status & MMC_ST0_CMD_TIMEOUT)
{
dbgprintf("CMD timeout");
return -EC_RESP_TIMEOUT;
}
if (status & MMC_ST0_DATA_TIMEOUT)
{
dbgprintf("DATA timeout");
return -EC_DATA_TIMEOUT;
}
if (status &
(MMC_ST0_WR_CRCERR | MMC_ST0_RD_CRCERR | MMC_ST0_RESP_CRCERR))
{
dbgprintf("CRC error");
return -EC_CRC_ERROR;
}
if (st_reg_num == 0)
{
done = status & flag;
}
else
{
done = status1 & flag;
}
} while (!done);
return EC_OK;
}
static int dma_wait_for_completion(void)
{
uint16_t dma_status;
semaphore_wait(&data_done, TIMEOUT_BLOCK);
dma_status = IO_MMC_SD_DMA_STATUS1;
if (dma_status & MMC_DMASTAT1_TOUTDT)
{
return -EC_DATA_TIMEOUT;
}
if (dma_status & MMC_DMASTAT1_RUNST)
{
panicf("Semaphore released while DMA still running");
}
return EC_OK;
}
static int sd_command(int cmd, unsigned long arg,
int cmdat, unsigned long *response)
{
int ret;
/* Clear response registers */
IO_MMC_RESPONSE0 = 0;
IO_MMC_RESPONSE1 = 0;
IO_MMC_RESPONSE2 = 0;
IO_MMC_RESPONSE3 = 0;
IO_MMC_RESPONSE4 = 0;
IO_MMC_RESPONSE5 = 0;
IO_MMC_RESPONSE6 = 0;
IO_MMC_RESPONSE7 = 0;
IO_MMC_COMMAND_INDEX = 0;
IO_MMC_SPI_DATA = 0;
IO_MMC_ARG_LOW = (unsigned int)((arg & 0xFFFF));
IO_MMC_ARG_HI = (unsigned int)((arg & 0xFFFF0000) >> 16);
/* SD is always in push-pull mode */
cmdat |= MMC_CMD_PPLEN;
cmdat |= (cmd & MMC_CMD_CMD_MASK);
if (cmdat & MMC_CMD_DATA)
cmdat |= MMC_CMD_DCLR;
IO_MMC_COMMAND = cmdat;
if (cmdat & MMC_CMD_DATA)
{
/* Command requires data - do not wait for RSPDNE */
ret = EC_OK;
}
else
{
ret = sd_poll_status(0, MMC_ST0_RSPDNE);
}
if (ret != EC_OK)
{
dbgprintf("Command failed (ret %d)", ret);
return ret;
}
if (response == NULL)
{
/* discard response */
}
else
{
switch (cmdat & SDHC_RESP_FMT_MASK)
{
case SDHC_RESP_FMT_1:
case SDHC_RESP_FMT_3:
response[0] = (IO_MMC_RESPONSE7 << 16) | IO_MMC_RESPONSE6;
break;
case SDHC_RESP_FMT_2:
response[0] = (IO_MMC_RESPONSE7 << 16) | IO_MMC_RESPONSE6;
response[1] = (IO_MMC_RESPONSE5 << 16) | IO_MMC_RESPONSE4;
response[2] = (IO_MMC_RESPONSE3 << 16) | IO_MMC_RESPONSE2;
response[3] = (IO_MMC_RESPONSE1 << 16) | IO_MMC_RESPONSE0;
break;
default:
break;
}
}
return 0;
}
static int sd_init_card(const int card_no)
{
bool sdhc = false;
unsigned long response[4];
int ret;
int i;
memset(currcard, 0, sizeof(*currcard));
sd_card_mux(card_no);
/* Set data bus width to 1 bit */
bitclr16(&IO_MMC_CONTROL, MMC_CTRL_WIDTH);
sd_set_clock_rate(INITIAL_CLK);
/* Prevent controller lock */
udelay(100);
ret = sd_command(SD_GO_IDLE_STATE, 0, MMC_CMD_INITCLK, NULL);
if (ret < 0)
return -1;
ret = sd_command(SD_SEND_IF_COND, 0x1AA,
SDHC_RESP_FMT_3, response);
if ((response[0] & 0xFFF) == 0x1AA)
{
sdhc = true;
dbgprintf("found sdhc card");
}
while ((currcard->ocr & (1 << 31)) == 0) /* until card is powered up */
{
ret = sd_command(SD_APP_CMD, currcard->rca,
SDHC_RESP_FMT_1, NULL);
if (ret < 0)
{
dbgprintf("SD_APP_CMD failed");
return -1;
}
ret = sd_command(SD_APP_OP_COND,
(1 << 20) /* 3.2-3.3V */ |
(1 << 21) /* 3.3-3.4V */ |
(sdhc ? (1 << 30) : 0),
SDHC_RESP_FMT_3, &currcard->ocr);
if (ret < 0)
{
dbgprintf("SD_APP_OP_COND failed");
return -1;
}
}
dbgprintf("Card powered up");
ret = sd_command(SD_ALL_SEND_CID, 0,
SDHC_RESP_FMT_2, response);
if (ret < 0)
{
dbgprintf("SD_ALL_SEND_CID failed");
return -1;
}
for (i = 0; i<4; i++)
{
currcard->cid[i] = response[i];
}
ret = sd_command(SD_SEND_RELATIVE_ADDR, 0,
SDHC_RESP_FMT_1, &currcard->rca);
if (ret < 0)
{
dbgprintf("SD_SEND_RELATIVE_ADDR failed");
return -1;
}
ret = sd_command(SD_SEND_CSD, currcard->rca,
SDHC_RESP_FMT_2, response);
if (ret < 0)
{
dbgprintf("SD_SEND_CSD failed");
return -1;
}
for (i = 0; i<4; i++)
{
currcard->csd[i] = response[i];
}
sd_parse_csd(currcard);
sd_set_clock_rate(currcard->speed);
/* Prevent controller lock */
udelay(100);
ret = sd_command(SD_SELECT_CARD, currcard->rca,
SDHC_RESP_FMT_1, NULL);
if (ret < 0)
{
dbgprintf("SD_SELECT_CARD failed");
return -1;
}
ret = sd_command(SD_APP_CMD, currcard->rca,
SDHC_RESP_FMT_1, NULL);
if (ret < 0)
{
dbgprintf("SD_APP_CMD failed");
return -1;
}
ret = sd_command(SD_SET_BUS_WIDTH, currcard->rca | 2,
SDHC_RESP_FMT_1, NULL); /* 4 bit */
if (ret < 0)
{
dbgprintf("SD_SET_BUS_WIDTH failed");
return -1;
}
/* Set data bus width to 4 bits */
bitset16(&IO_MMC_CONTROL, MMC_CTRL_WIDTH);
ret = sd_command(SD_SET_BLOCKLEN, currcard->blocksize,
SDHC_RESP_FMT_1, NULL);
if (ret < 0)
{
dbgprintf("SD_SET_BLOCKLEN failed");
return -1;
}
IO_MMC_BLOCK_LENGTH = currcard->blocksize;
dbgprintf("Card initialized");
currcard->initialized = 1;
return EC_OK;
}
/* lock must already by aquired */
static void sd_select_device(int card_no)
{
currcard = &card_info[card_no];
if (card_no == 0)
{
/* Main card always gets a chance */
sd_status[0].retry = 0;
}
if (currcard->initialized > 0)
{
/* This card is already initialized - switch to it */
sd_card_mux(card_no);
return;
}
if (currcard->initialized == 0)
{
/* Card needs (re)init */
sd_init_card(card_no);
}
}
static inline bool card_detect_target(void)
{
#ifdef SANSA_CONNECT
bool removed;
removed = IO_GIO_BITSET0 & (1 << 14);
return !removed;
#else
return false;
#endif
}
#ifdef HAVE_HOTSWAP
static int sd1_oneshot_callback(struct timeout *tmo)
{
/* This is called only if the state was stable for 300ms - check state
* and post appropriate event. */
queue_broadcast(card_detect_target() ? SYS_HOTSWAP_INSERTED :
SYS_HOTSWAP_EXTRACTED,
CARD_NUM_SLOT);
return 0;
(void)tmo;
}
#ifdef SANSA_CONNECT
void GIO14(void) __attribute__ ((section(".icode")));
void GIO14(void)
{
static struct timeout sd1_oneshot;
/* clear interrupt */
IO_INTC_IRQ2 = (1<<3);
timeout_register(&sd1_oneshot, sd1_oneshot_callback, (3*HZ/10), 0);
}
#endif
bool sd_removable(IF_MD_NONVOID(int card_no))
{
#ifndef HAVE_MULTIDRIVE
const int card_no = 0;
#endif
return (card_no == CARD_NUM_SLOT);
}
bool sd_present(IF_MD_NONVOID(int card_no))
{
#ifndef HAVE_MULTIDRIVE
const int card_no = 0;
#endif
return (card_no == CARD_NUM_SLOT) ? card_detect_target() :
#ifdef SANSA_CONNECT
true; /* iNAND is always present */
#else
false;
#endif
}
#else /* no hotswap */
bool sd_removable(IF_MD_NONVOID(int card_no))
{
#ifdef HAVE_MULTIDRIVE
(void)card_no;
#endif
/* not applicable */
return false;
}
#endif /* HAVE_HOTSWAP */
static int sd_wait_for_state(unsigned int state)
{
unsigned long response = 0;
unsigned int timeout = HZ; /* ticks */
long t = current_tick;
while (1)
{
long tick;
int ret = sd_command(SD_SEND_STATUS, currcard->rca,
SDHC_RESP_FMT_1, &response);
if (ret < 0)
return ret;
if ((SD_R1_CURRENT_STATE(response) == state))
{
return EC_OK;
}
if(TIME_AFTER(current_tick, t + timeout))
return -2;
if (TIME_AFTER((tick = current_tick), next_yield))
{
yield();
timeout += current_tick - tick;
next_yield = tick + MIN_YIELD_PERIOD;
}
}
}
static int sd_transfer_sectors(int card_no, unsigned long start,
int count, void *buffer, bool write)
{
int ret;
unsigned long start_addr;
int dma_channel = -1;
bool use_direct_dma;
int count_per_dma;
unsigned long rel_addr;
dbgprintf("transfer %d %d %d", card_no, start, count);
mutex_lock(&sd_mtx);
enable_controller(true);
sd_transfer_retry:
if (card_no == CARD_NUM_SLOT && !card_detect_target())
{
/* no external sd-card inserted */
ret = -EC_NOCARD;
goto sd_transfer_error;
}
sd_select_device(card_no);
if (currcard->initialized < 0)
{
ret = currcard->initialized;
goto sd_transfer_error;
}
last_disk_activity = current_tick;
ret = sd_wait_for_state(SD_TRAN);
if (ret < EC_OK)
{
goto sd_transfer_error;
}
IO_MMC_BLOCK_LENGTH = currcard->blocksize;
start_addr = start;
do
{
count_per_dma = count;
if (((unsigned long)buffer) & 0x1F)
{
/* MMC/SD interface requires 32-byte alignment of buffer */
use_direct_dma = false;
if (count > UNALIGNED_NUM_SECTORS)
{
count_per_dma = UNALIGNED_NUM_SECTORS;
}
}
else
{
use_direct_dma = true;
}
if (write == true)
{
if (use_direct_dma == false)
{
memcpy(aligned_buffer, buffer, count_per_dma*SD_BLOCK_SIZE);
}
commit_dcache_range(use_direct_dma ? buffer : aligned_buffer,
count_per_dma*SD_BLOCK_SIZE);
}
IO_MMC_NR_BLOCKS = count_per_dma;
/* Set start_addr to the correct unit (blocks or bytes) */
if (!(card_info[card_no].ocr & SD_OCR_CARD_CAPACITY_STATUS))
start_addr *= SD_BLOCK_SIZE; /* not SDHC */
ret = sd_command(write ? SD_WRITE_MULTIPLE_BLOCK : SD_READ_MULTIPLE_BLOCK,
start_addr, MMC_CMD_DCLR | MMC_CMD_DATA |
SDHC_RESP_FMT_1 | (write ? MMC_CMD_WRITE : 0),
NULL);
if (ret < 0)
goto sd_transfer_error;
/* other burst modes are not supported for this peripheral */
dma_channel = dma_request_channel(DMA_PERIPHERAL_MMCSD,
DMA_MODE_8_BURST);
if (use_direct_dma == true)
{
rel_addr = ((unsigned long)buffer)-CONFIG_SDRAM_START;
}
else
{
rel_addr = ((unsigned long)aligned_buffer)-CONFIG_SDRAM_START;
}
IO_MMC_SD_DMA_ADDR_LOW = rel_addr & 0xFFFF;
IO_MMC_SD_DMA_ADDR_HI = (rel_addr & 0xFFFF0000) >> 16;
IO_MMC_SD_DMA_MODE |= MMC_DMAMODE_ENABLE;
if (write == true)
{
IO_MMC_SD_DMA_MODE |= MMC_DMAMODE_WRITE;
}
IO_MMC_SD_DMA_TRIGGER = 1;
dbgprintf("SD DMA transfer in progress");
ret = dma_wait_for_completion();
dma_release_channel(dma_channel);
dbgprintf("SD DMA transfer complete");
if (ret != EC_OK)
{
goto sd_transfer_error;
}
if (write == false)
{
discard_dcache_range(use_direct_dma ? buffer : aligned_buffer,
count_per_dma*SD_BLOCK_SIZE);
if (use_direct_dma == false)
{
memcpy(buffer, aligned_buffer, count_per_dma*SD_BLOCK_SIZE);
}
}
last_disk_activity = current_tick;
ret = sd_command(SD_STOP_TRANSMISSION, 0, SDHC_RESP_FMT_1, NULL);
if (ret < 0)
{
goto sd_transfer_error;
}
ret = sd_wait_for_state(SD_TRAN);
if (ret < 0)
{
goto sd_transfer_error;
}
count -= count_per_dma;
buffer += count_per_dma*SD_BLOCK_SIZE;
start_addr += count_per_dma;
} while (count > 0);
while (1)
{
enable_controller(false);
mutex_unlock(&sd_mtx);
return ret;
sd_transfer_error:
if (sd_status[card_no].retry < sd_status[card_no].retry_max
&& ret != -EC_NOCARD)
{
sd_status[card_no].retry++;
currcard->initialized = 0;
goto sd_transfer_retry;
}
}
}
int sd_read_sectors(IF_MD(int card_no,) unsigned long start, int incount,
void* inbuf)
{
#ifndef HAVE_MULTIDRIVE
const int card_no = 0;
#endif
return sd_transfer_sectors(card_no, start, incount, inbuf, false);
}
int sd_write_sectors(IF_MD(int card_no,) unsigned long start, int count,
const void* outbuf)
{
#ifndef HAVE_MULTIDRIVE
const int card_no = 0;
#endif
return sd_transfer_sectors(card_no, start, count, (void*)outbuf, true);
}
int sd_init(void)
{
int ret = EC_OK;
if (!initialized)
{
mutex_init(&sd_mtx);
semaphore_init(&data_done, 1, 0);
initialized = true;
}
mutex_lock(&sd_mtx);
enable_controller(false);
/* based on linux/drivers/mmc/dm320mmc.c
Copyright (C) 2006 ZSI, All Rights Reserved.
Written by: Ben Bostwick */
bitclr16(&IO_CLK_MOD2, CLK_MOD2_MMC);
bitset16(&IO_CLK_INV, CLK_INV_MMC);
/* mmc module clock when boosted 74.25 Mhz (AHB) / 2 = 37.125 Mhz
* default 37.125 (AHB) / 2 = 18.5625 MHz
* (Frequencies above are valid for Sansa Connect) */
IO_CLK_DIV3 = (IO_CLK_DIV3 & 0xFF00) | 0x01;
bitset16(&IO_CLK_MOD2, CLK_MOD2_MMC);
/* set mmc module into reset */
bitset16(&IO_MMC_CONTROL, (MMC_CTRL_DATRST | MMC_CTRL_CMDRST));
/* set resp timeout to max */
IO_MMC_RESPONSE_TIMEOUT |= 0x1FFF;
IO_MMC_READ_TIMEOUT = 0xFFFF;
/* all done, take mmc module out of reset */
bitclr16(&IO_MMC_CONTROL, (MMC_CTRL_DATRST | MMC_CTRL_CMDRST));
#ifdef SANSA_CONNECT
/* GIO37 - Power Card; GIO38 - Power iNAND (both active low) */
IO_GIO_DIR2 &= ~((1 << 5) /* GIO37 */ | (1 << 6) /* GIO38 */);
IO_GIO_INV2 &= ~((1 << 5) /* GIO37 */ | (1 << 6) /* GIO38 */);
IO_GIO_BITCLR2 = (1 << 5) | (1 << 6);
/* GIO6 - select Card; GIO5 - select iNAND (both active low) */
IO_GIO_DIR0 &= ~((1 << 6) /* GIO6 */ | (1 << 5) /* GIO5 */);
IO_GIO_INV0 &= ~((1 << 6) /* GIO6 */ | (1 << 5) /* GIO5 */);
IO_GIO_BITSET0 = (1 << 6) | (1 << 5);
#ifdef HAVE_HOTSWAP
/* GIO14 is card detect */
IO_GIO_DIR0 |= (1 << 14); /* Set GIO14 as input */
IO_GIO_INV0 &= ~(1 << 14); /* GIO14 not inverted */
IO_GIO_IRQPORT |= (1 << 14); /* Enable GIO14 external interrupt */
IO_GIO_IRQEDGE |= (1 << 14); /* Any edge detection */
/* Enable GIO14 interrupt */
IO_INTC_EINT2 |= INTR_EINT2_EXT14;
#endif
#endif
/* Enable data done interrupt */
IO_MMC_INT_ENABLE |= MMC_IE_EDATDNE;
IO_INTC_EINT1 |= INTR_EINT1_MMCSDMS0;
/* Disable Memory Card CLK - it is enabled on demand by TMS320DM320 */
bitclr16(&IO_MMC_MEM_CLK_CONTROL, (1 << 8));
mutex_unlock(&sd_mtx);
return ret;
}
long sd_last_disk_activity(void)
{
return last_disk_activity;
}
tCardInfo *card_get_info_target(int card_no)
{
return &card_info[card_no];
}
int sd_event(long id, intptr_t data)
{
int rc = 0;
switch (id)
{
#ifdef HAVE_HOTSWAP
case SYS_HOTSWAP_INSERTED:
case SYS_HOTSWAP_EXTRACTED:
mutex_lock(&sd_mtx); /* lock-out card activity */
/* Force card init for new card, re-init for re-inserted one or
* clear if the last attempt to init failed with an error. */
card_info[data].initialized = 0;
mutex_unlock(&sd_mtx);
break;
#endif /* HAVE_HOTSWAP */
default:
rc = storage_event_default_handler(id, data, last_disk_activity,
STORAGE_SD);
break;
}
return rc;
}
void SD_MMC(void) __attribute__ ((section(".icode")));
void SD_MMC(void)
{
uint16_t status = IO_MMC_STATUS0;
/* Clear interrupt */
IO_INTC_IRQ1 = INTR_IRQ1_MMCSDMS0;
if (status & MMC_ST0_DATDNE)
{
semaphore_release(&data_done);
}
}