[U-Boot] dfu: make data buffer size configurable

[Heiko Schocher]

Dfu transfer uses a buffer before writing data to the
raw storage device. Make the size (in bytes) of this buffer
configurable.

Signed-off-by: Heiko Schocher <hs at denx.de>
Cc: Pantelis Antoniou <panto at antoniou-consulting.com>
Cc: Tom Rini <trini at ti.com>
Cc: Lukasz Majewski <l.majewski at samsung.com>
Cc: Kyungmin Park <kyungmin.park at samsung.com>
Cc: Marek Vasut <marex at denx.de>
---
 README            | 5 +++++
 drivers/dfu/dfu.c | 2 +-
 include/dfu.h     | 4 +++-
 3 Dateien geändert, 9 Zeilen hinzugefügt(+), 2 Zeilen entfernt(-)

diff --git a/README b/README
index b1b3e17..8550f34 100644
--- a/README
+++ b/README
@@ -1360,6 +1360,11 @@ The following options need to be configured:
 		CONFIG_DFU_NAND
 		This enables support for exposing NAND devices via DFU.
 
+		CONFIG_SYS_DFU_DATA_BUF_SIZE
+		Dfu transfer uses a buffer before writing data to the
+		raw storage device. Make the size (in bytes) of this buffer
+		configurable.
+
 		CONFIG_SYS_DFU_MAX_FILE_SIZE
 		When updating files rather than the raw storage device,
 		we use a static buffer to copy the file into and then write
diff --git a/drivers/dfu/dfu.c b/drivers/dfu/dfu.c
index 6af6890..fe3a36e 100644
--- a/drivers/dfu/dfu.c
+++ b/drivers/dfu/dfu.c
@@ -42,7 +42,7 @@ static int dfu_find_alt_num(const char *s)
 }
 
 static unsigned char __aligned(CONFIG_SYS_CACHELINE_SIZE)
-				     dfu_buf[DFU_DATA_BUF_SIZE];
+				     dfu_buf[CONFIG_SYS_DFU_DATA_BUF_SIZE];
 
 static int dfu_write_buffer_drain(struct dfu_entity *dfu)
 {
diff --git a/include/dfu.h b/include/dfu.h
index a107f4b..124653c 100644
--- a/include/dfu.h
+++ b/include/dfu.h
@@ -68,7 +68,9 @@ static inline unsigned int get_mmc_blk_size(int dev)
 
 #define DFU_NAME_SIZE			32
 #define DFU_CMD_BUF_SIZE		128
-#define DFU_DATA_BUF_SIZE		(1024*1024*8)	/* 8 MiB */
+#ifndef CONFIG_SYS_DFU_DATA_BUF_SIZE
+#define CONFIG_SYS_DFU_DATA_BUF_SIZE		(1024*1024*8)	/* 8 MiB */
+#endif
 #ifndef CONFIG_SYS_DFU_MAX_FILE_SIZE
 #define CONFIG_SYS_DFU_MAX_FILE_SIZE	(4 << 20)	/* 4 MiB */
 #endif
-- 
1.7.11.7