[PATCH v2 2/2] fs: Use ARCH_DMA_MINALIGN as default alignment for fs_read_alloc()

[Nam Cao]

The comment above fs_read_alloc() explains:

    @align: Alignment to use for memory allocation (0 for default)

However, in the actual implementation, there is no alignment when @align is
zero.

This current default is probably fine for most cases. But for some block
devices which transfer data via DMA, ARCH_DMA_MINALIGN is needed.

Change the default alignment to ARCH_DMA_MINALIGN.

Fixes: de7b5a8a1ac0 ("fs: Create functions to load and allocate a file")
Signed-off-by: Nam Cao <namcao at linutronix.de>
Tested-by: Javier Fernandez Pastrana <javier.pastrana at linutronix.de>
---
v2:
  - mention the default value in function comment [Simon]

 fs/fs.c      | 4 ++++
 include/fs.h | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/fs.c b/fs/fs.c
index acf465bdd80..bfa51c89d40 100644
--- a/fs/fs.c
+++ b/fs/fs.c
@@ -23,6 +23,7 @@
 #include <semihostingfs.h>
 #include <ubifs_uboot.h>
 #include <btrfs.h>
+#include <asm/cache.h>
 #include <asm/global_data.h>
 #include <asm/io.h>
 #include <div64.h>
@@ -1001,6 +1002,9 @@ int fs_read_alloc(const char *fname, ulong size, uint align, void **bufp)
 	char *buf;
 	int ret;
 
+	if (!align)
+		align = ARCH_DMA_MINALIGN;
+
 	buf = memalign(align, size + 1);
 	if (!buf)
 		return log_msg_ret("buf", -ENOMEM);
diff --git a/include/fs.h b/include/fs.h
index ef540e7c23d..2f879968d0c 100644
--- a/include/fs.h
+++ b/include/fs.h
@@ -309,7 +309,7 @@ int do_fs_types(struct cmd_tbl *cmdtp, int flag, int argc, char * const argv[]);
  *
  * @fname: Filename to read
  * @size: Size of file to read (must be correct!)
- * @align: Alignment to use for memory allocation (0 for default)
+ * @align: Alignment to use for memory allocation (0 for default: ARCH_DMA_MINALIGN)
  * @bufp: On success, returns the allocated buffer with the nul-terminated file
  *	in it
  * Return: 0 if OK, -ENOMEM if out of memory, -EIO if read failed
-- 
2.39.5