Currently in do_fat_read() when reading FAT sectors, we have to divide down LINEAR_PREFETCH_SIZE by the sector size, whereas it's defined as 2 sectors worth of bytes. In order to avoid redundant multiplication/division, introduce #define PREFETCH_BLOCKS instead of #define LINEAR_PREFETCH_SIZE.

Signed-off-by: Sergei Shtylyov sshtylyov@mvista.com

--- Slight optimization atop of commit 3831530dcb7b71329c272ccd6181f8038b6a6dd0 (VFAT: fix processing of scattered long file name entries) and my recently submitted patch fixing crash with big sector size.

The patch was generated atop of the below patches posted earlier: http://marc.info/?l=u-boot&m=131283284822789 http://marc.info/?l=u-boot&m=131283289722891

fs/fat/fat.c | 9 ++++----- include/fat.h | 2 +- 2 files changed, 5 insertions(+), 6 deletions(-)

Index: u-boot/fs/fat/fat.c =================================================================== --- u-boot.orig/fs/fat/fat.c +++ u-boot/fs/fat/fat.c @@ -440,10 +440,9 @@ get_vfatname (fsdata *mydata, int curclu { dir_entry *realdent; dir_slot *slotptr = (dir_slot *)retdent; - __u8 *buflimit = cluster + ((curclust == 0) ? - LINEAR_PREFETCH_SIZE : - (mydata->clust_size * mydata->sect_size) - ); + __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ? + PREFETCH_BLOCKS : + mydata->clust_size); __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff; int idx = 0;

@@ -880,7 +879,7 @@ do_fat_read (const char *filename, void if (disk_read(cursect, (mydata->fatsize == 32) ? (mydata->clust_size) : - LINEAR_PREFETCH_SIZE / mydata->sect_size, + PREFETCH_BLOCKS, do_fat_read_block) < 0) { debug("Error: reading rootdir block\n"); goto exit; Index: u-boot/include/fat.h =================================================================== --- u-boot.orig/include/fat.h +++ u-boot/include/fat.h @@ -33,7 +33,7 @@ /* Maximum Long File Name length supported here is 128 UTF-16 code units */ #define VFAT_MAXLEN_BYTES 256 /* Maximum LFN buffer in bytes */ #define VFAT_MAXSEQ 9 /* Up to 9 of 13 2-byte UTF-16 entries */ -#define LINEAR_PREFETCH_SIZE (mydata->sect_size*2) /* Prefetch buffer size */ +#define PREFETCH_BLOCKS 2

#define MAX_CLUSTSIZE 65536 #define DIRENTSPERBLOCK (mydata->sect_size / sizeof(dir_entry))