Improve read performance by switching to DMA and mult-block operations

fatfs/diskio.c

@@ -28,12 +28,10 @@ DSTATUS disk_status (
 	BYTE pdrv		/* Physical drive nmuber to identify the drive */
 )
 {
-	DSTATUS stat;
-	int result;
 
 	switch (pdrv) {
 	case DEV_SD:
-        return sdio_status();
+		return sdio_status();
 	}
 	return STA_NOINIT;
 }
@@ -48,12 +46,9 @@ DSTATUS disk_initialize (
 	BYTE pdrv				/* Physical drive nmuber to identify the drive */
 )
 {
-	DSTATUS stat;
-	int result;
-
 	switch (pdrv) {
 	case DEV_SD:
-        return sdio_initialize();
+		return sdio_initialize();
 	}
 	return STA_NOINIT;
 }
@@ -71,12 +66,9 @@ DRESULT disk_read (
 	UINT count		/* Number of sectors to read */
 )
 {
-	DRESULT res;
-	int result;
-
 	switch (pdrv) {
 	case DEV_SD:
-        return sdio_disk_read(buff, sector, count);
+		return sdio_disk_read(buff, sector, count);
 	}
 	return RES_PARERR;
 }
@@ -96,12 +88,9 @@ DRESULT disk_write (
 	UINT count			/* Number of sectors to write */
 )
 {
-	DRESULT res;
-	int result;
-
 	switch (pdrv) {
 	case DEV_SD:
-		return SDIO_disk_write(buff, sector, count);
+		return sdio_disk_write(buff, sector, count);
 	}
 
 	return RES_PARERR;
@@ -120,12 +109,9 @@ DRESULT disk_ioctl (
 	void *buff		/* Buffer to send/receive control data */
 )
 {
-	DRESULT res;
-	int result;
-
 	switch (pdrv) {
 	case DEV_SD:
-        return sdio_disk_ioctl(cmd, buff);
+		return sdio_disk_ioctl(cmd, buff);
 	}
 
 	return RES_PARERR;

fatfs/shimatta_sdio_driver/shimatta_sdio_config.h

@@ -14,13 +14,16 @@
 //Initial Transfer CLK (ca. 400kHz)
 #define INITCLK   130   //120
 //Working CLK (Maximum)
-#define WORKCLK   50   //0
+#define WORKCLK   2   //0
 //Data Timeout in CLK Cycles
-#define DTIMEOUT  0x3000   //150
+#define DTIMEOUT  0x8000   //150
 //DMA Stream used for TX and RX DMA2 Stream 3 or 6 possible
-// Currently not used due to possible misalignment of the data buffer.
-//#define DMASTREAM DMA2_Stream6
 
+#define USE_DMA 1
+
+#define DMASTREAM DMA2_Stream6
+
+#define DMASTREAM_NO 6
 
 /* Port Definitions */
 

include/fatfs/ffconf.h

@@ -8,7 +8,7 @@
 / Function Configurations
 /---------------------------------------------------------------------------*/
 
-#define FF_FS_READONLY	1
+#define FF_FS_READONLY	0
 /* This option switches read-only configuration. (0:Read/Write or 1:Read-only)
 /  Read-only configuration removes writing API functions, f_write(), f_sync(),
 /  f_unlink(), f_mkdir(), f_chmod(), f_rename(), f_truncate(), f_getfree()

main.c

@@ -22,10 +22,16 @@ volatile uint32_t sdio_wait;
 
 int initreq = 0xFF;
 
-int main() {
-	char buff[1024];
+//const char *write_string = "This is a write test. Okay... Writing seems to work. Let's close the file\n";
+
+char buff[8192*6];
+
+int main()
+{
+	int i;
 	char *name;
 	FILINFO fno;
+
 	RCC->AHB1ENR |= RCC_AHB1ENR_GPIOAEN;
 	__DSB();
 	GPIOA->MODER |= OUTPUT(6) | OUTPUT(7);
@@ -39,20 +45,20 @@ int main() {
 	initreq = f_mount(&SDfs, "0:/", 1);
 	while(initreq);
 
-	initreq = f_opendir(&root, "/");
-	if (initreq == FR_OK) {
-		if (!f_readdir(&root, &fno))
-		{
-			name = fno.fname;
-			initreq = f_open(&file, name, FA_READ);
-				if (initreq == FR_OK) {
-					f_gets(buff, sizeof(buff), &file);
-					printf("%s:\r\n%s\r\n",name, buff);
-					f_close(&file);
-				}
+	for (i = 0; i < 8192*6; i++)
+		buff[i] = 'A';
 
+	initreq = f_open(&file, "foo.txt", FA_OPEN_APPEND | FA_WRITE);
+	if (initreq == FR_OK) {
+		for (i = 0; i < 100; i++) {
+			initreq = f_write(&file, buff, 8192*6, NULL);
+			if (initreq) {
+				initreq++;
+			}
 		}
+		initreq = f_close(&file);
 	}
+
 //fflush(stdout);
 
 while(1);

program-device.gdb

@@ -0,0 +1,8 @@
+target extended-remote :2331
+monitor speed 4000
+monitor reset
+load
+monitor reset
+kill
+quit
+

program-device.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+
+JLinkGDBServer -if SWD -device STM32F407VE &
+sleep 2
+
+# Check if GDB server is still running
+gdbpid=`pidof JLinkGDBServer`
+
+if [[ $gdbpid == "" ]]; then
+	echo ""
+	echo "GDB Server not running! Check target connection."
+	exit
+fi
+
+arm-none-eabi-gdb -x program-device.gdb stm32f4sdio.elf
+sleep 2
+
+kill $gdbpid

stm32f407vgt6_flash.ld

@@ -152,7 +152,7 @@ SECTIONS
 
   /* Uninitialized data section */
   . = ALIGN(4);
-  .bss :
+  .bss (NOLOAD):
   {
     /* This is used by the startup in order to initialize the .bss secion */
     _sbss = .;         /* define a global symbol at bss start */
@@ -167,7 +167,7 @@ SECTIONS
   } >RAM
 
   /* User_heap_stack section, used to check that there is enough RAM left */
-  ._user_heap_stack :
+  ._user_heap_stack (NOLOAD):
   {
     . = ALIGN(4);
     PROVIDE (heap_low = .); /* for _sbrk */