From 953c42c0ea7e1c27793ba465db862e2fbc7ffdf9 Mon Sep 17 00:00:00 2001
From: Bernie Innocenti <bernie@codewiz.org>
Date: Fri, 25 Mar 2011 16:04:35 -0400
Subject: [PATCH] Speedup write to SD card with various tricks

---
 rmslog/cfg/cfg_ser.h | 87 ++------------------------------------------
 rmslog/main.c        | 49 +++++++++++++------------
 2 files changed, 29 insertions(+), 107 deletions(-)

diff --git a/rmslog/cfg/cfg_ser.h b/rmslog/cfg/cfg_ser.h
index b5ce58a..b2524cc 100644
--- a/rmslog/cfg/cfg_ser.h
+++ b/rmslog/cfg/cfg_ser.h
@@ -49,7 +49,7 @@
  * $WIZ$ type = "int"
  * $WIZ$ min = 2
  */
-#define CONFIG_UART0_TXBUFSIZE  32
+#define CONFIG_UART0_TXBUFSIZE  16
 
 /**
  * Size of the inbound FIFO buffer for port 0 [bytes].
@@ -58,62 +58,13 @@
  */
 #define CONFIG_UART0_RXBUFSIZE  512
 
-/**
- * Size of the outbound FIFO buffer for port 1 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "lm3s or lpc2 or (at91 and not atmega8 and not atmega168 and not atmega32)"
- */
-#define CONFIG_UART1_TXBUFSIZE  32
-
-/**
- * Size of the inbound FIFO buffer for port 1 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "lm3s or lpc2 or (at91 and not atmega8 and not atmega168 and not atmega32)"
- */
-#define CONFIG_UART1_RXBUFSIZE  32
-
-/**
- * Size of the outbound FIFO buffer for port 2 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "lm3s or lpc2"
- */
-#define CONFIG_UART2_TXBUFSIZE  32
-
-/**
- * Size of the inbound FIFO buffer for port 2 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "lm3s or lpc2"
- */
-#define CONFIG_UART2_RXBUFSIZE  32
-
-/**
- * Size of the outbound FIFO buffer for port 3 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "lpc2"
- */
-#define CONFIG_UART3_TXBUFSIZE  32
-
-/**
- * Size of the inbound FIFO buffer for port 3 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "lpc2"
- */
-#define CONFIG_UART3_RXBUFSIZE  32
-
-
 /**
  * Size of the outbound FIFO buffer for SPI port [bytes].
  * $WIZ$ type = "int"
  * $WIZ$ min = 2
  * $WIZ$ supports = "avr"
  */
-#define CONFIG_SPI_TXBUFSIZE    32
+#define CONFIG_SPI_TXBUFSIZE    0
 
 /**
  * Size of the inbound FIFO buffer for SPI port [bytes].
@@ -121,39 +72,7 @@
  * $WIZ$ min = 2
  * $WIZ$ supports = "avr"
  */
-#define CONFIG_SPI_RXBUFSIZE    32
-
-/**
- * Size of the outbound FIFO buffer for SPI port 0 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "at91"
- */
-#define CONFIG_SPI0_TXBUFSIZE	32
-
-/**
- * Size of the inbound FIFO buffer for SPI port 0 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "at91"
- */
-#define CONFIG_SPI0_RXBUFSIZE	32
-
-/**
- * Size of the outbound FIFO buffer for SPI port 1 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "at91"
- */
-#define CONFIG_SPI1_TXBUFSIZE	32
-
-/**
- * Size of the inbound FIFO buffer for SPI port 1 [bytes].
- * $WIZ$ type = "int"
- * $WIZ$ min = 2
- * $WIZ$ supports = "at91"
- */
-#define CONFIG_SPI1_RXBUFSIZE	32
+#define CONFIG_SPI_RXBUFSIZE    0
 
 /**
  * SPI data order.
diff --git a/rmslog/main.c b/rmslog/main.c
index 9f52d5f..d4bb6a0 100644
--- a/rmslog/main.c
+++ b/rmslog/main.c
@@ -10,6 +10,11 @@
  * console messages.
  */
 
+#define FILE_NAME          "log.txt"
+#define FILE_OVERWRITE     1
+#define FILE_PREALLOC_SIZE 102400
+
+
 #include "hw/hw_led.h"
 
 #define LOG_LEVEL      3
@@ -150,9 +155,6 @@ static void init(void)
 	timer_delay(1000);
 	kfile_printf(&ser.fd, "Hello, world!\r\n");
 
-#ifdef BERTOS_FAT
-	ser_init(&spi, SER_SPI);
-#else
 	DDRB |= BV(PORTB0) | BV(PORTB2) | BV(PORTB3) | BV(PORTB5);
 	if (!sd_raw_init())
 	{
@@ -168,35 +170,36 @@ int main(void)
 {
 	init();
 
-#ifdef BERTOS_FAT
+	size_t size;
+	char buf[256];
+	bool sync_pending = false;
 
-	FRESULT fat_err;
-	if ((fat_err = f_mount(0, &fs)) != FR_OK)
+	/* create file */
+	if(!fat_create_file(dd, FILE_NAME, &dir_entry))
 	{
-		LOG_ERR("Error mounting FAT volume: %d\n", fat_err);
+		#if FILE_OVERWRITE
+			fat_delete_file(fs, &dir_entry);
+			fat_create_file(dd, FILE_NAME, &dir_entry);
+		#endif
 	}
 
-	fat_err = fatfile_open(&file, "foo.txt", FA_WRITE | FA_CREATE_ALWAYS);
-	ASSERT(fat_err == FR_OK);
-
-	size_t count = kfile_write(&file.fd, "Hello, world!", strlen("Hello, world!"));
-	ASSERT(count == strlen("Hello, world!"));
+	fd = open_file_in_dir(fs, dd, FILE_NAME);
 
-#else
-
-	fat_create_file(dd, "log.txt", &dir_entry);
-	fd = open_file_in_dir(fs, dd, "log.txt");
-	int32_t offset = 0;
-	fat_seek_file(fd, &offset, FAT_SEEK_END);
+	/* preallocate file */
+	#if FILE_PREALLOC_SIZE
+	{
+		LED_ON();
+		for (int i = 0; i < (int)(FILE_PREALLOC_SIZE / sizeof(buf)); ++i)
+			fat_write_file(fd, (void *)buf, sizeof(buf));
 
-#endif
+		int32_t offset = 0;
+		fat_seek_file(fd, &offset, FAT_SEEK_SET);
+		LED_OFF();
+	}
+	#endif
 
 	while (1)
 	{
-		size_t size;
-		char buf[128];
-		bool sync_pending = false;
-
 		if ((size = ser_read(&ser, buf, sizeof(buf))) != 0)
 		{
 			LED_ON();
-- 
2.25.1