[U-Boot] [PATCH v2 02/17] x86: Speed up copy-to-RAM and clear BSS operations

Graeme Russ graeme.russ at gmail.com
Wed Jan 4 20:59:40 CET 2012


The implementations of memcpy and memset are now the optimised versions
from glibc, so use them instead of simple copy loops

Signed-off-by: Graeme Russ <graeme.russ at gmail.com>
---
Changes for v2:
 - Removed unneeded brackets

 arch/x86/lib/board.c |   17 +++++------------
 1 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/arch/x86/lib/board.c b/arch/x86/lib/board.c
index d742fec..f9eb15b 100644
--- a/arch/x86/lib/board.c
+++ b/arch/x86/lib/board.c
@@ -188,26 +188,19 @@ static int calculate_relocation_address(void)

 static int copy_uboot_to_ram(void)
 {
-	ulong *dst_addr = (ulong *)gd->relocaddr;
-	ulong *src_addr = (ulong *)&__text_start;
-	ulong *end_addr = (ulong *)&__data_end;
+	size_t len = (size_t)&__data_end - (size_t)&__text_start;

-	while (src_addr < end_addr)
-		*dst_addr++ = *src_addr++;
+	memcpy((void *)gd->relocaddr, (void *)&__text_start, len);

 	return 0;
 }

 static int clear_bss(void)
 {
-	void *bss_start = &__bss_start;
-	void *bss_end = &__bss_end;
+	ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;
+	size_t len = (size_t)&__bss_end - (size_t)&__bss_start;

-	ulong *dst_addr = (ulong *)(bss_start + gd->reloc_off);
-	ulong *end_addr = (ulong *)(bss_end + gd->reloc_off);
-
-	while (dst_addr < end_addr)
-		*dst_addr++ = 0x00000000;
+	memset((void *)dst_addr, 0x00, len);

 	return 0;
 }
--
1.7.5.2.317.g391b14



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