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authorMatthias Weisser <weisserm@arcor.de>2011-03-10 21:36:32 +0000
committerAlbert ARIBAUD <albert.u.boot@aribaud.net>2011-04-27 19:38:07 +0200
commitd8834a1323af72f6145bc81adadd75185ef6065f (patch)
treec8e04b59f251c9ea1e8dc0097ba8ca83a6fef31f /README
parentb65a77a8613d974cb665d14c51a012a8c12b8ba1 (diff)
downloadu-boot-linaro-stable-d8834a1323af72f6145bc81adadd75185ef6065f.tar.gz
arm: Use optimized memcpy and memset from linux
Using optimized versions of memset and memcpy from linux brings a quite noticeable speed (x2 or better) improvement for these two functions. Here are some numbers for test done with jadecpu | HEAD(1)| HEAD(1)| HEAD(2)| HEAD(2)| | | +patch | | +patch | ---------------------------+--------+--------+--------+--------+ Reset to prompt | 438ms | 330ms | 228ms | 120ms | | | | | | TFTP a 3MB img | 4782ms | 3428ms | 3245ms | 2820ms | | | | | | FATLOAD USB a 3MB img* | 8515ms | 8510ms | ------ | ------ | | | | | | BOOTM LZO img in RAM | 3473ms | 3168ms | 592ms | 592ms | where CRC is | 615ms | 615ms | 54ms | 54ms | uncompress | 2460ms | 2462ms | 450ms | 451ms | final boot_elf | 376ms | 68ms | 65ms | 65ms | | | | | | BOOTM LZO img in FLASH | 3207ms | 2902ms | 1050ms | 1050ms | where CRC is | 600ms | 600ms | 135ms | 135ms | uncompress | 2209ms | 2211ms | 828ms | 828ms | | | | | | Copy 1.4MB from NOR to RAM | 134ms | 72ms | 120ms | 70ms | (1) No dcache (2) dcache enabled in board_init *Does not work when dcache is on Size impact: C version: text data bss dec hex filename 202862 18912 266456 488230 77326 u-boot ASM version: text data bss dec hex filename 203798 18912 266288 488998 77626 u-boot 222712 u-boot.bin Signed-off-by: Matthias Weisser <weisserm@arcor.de>
Diffstat (limited to 'README')
-rw-r--r--README6
1 files changed, 6 insertions, 0 deletions
diff --git a/README b/README
index cdbb9de02..85cbb8e02 100644
--- a/README
+++ b/README
@@ -2944,6 +2944,12 @@ Low Level (hardware related) configuration options:
that is executed before the actual U-Boot. E.g. when
compiling a NAND SPL.
+- CONFIG_USE_ARCH_MEMCPY
+ CONFIG_USE_ARCH_MEMSET
+ If these options are used a optimized version of memcpy/memset will
+ be used if available. These functions may be faster under some
+ conditions but may increase the binary size.
+
Building the Software:
======================