Re: [U-Boot] [PATCH] arm: lib: memcpy: Do not copy to same address

Am 23.05.2011 11:06, schrieb Matthias Weisser:

In some cases (e.g. bootm with a elf payload which is already at the right position) there is a in place copy of data to the same address. Catching this saves some ms while booting.

Signed-off-by: Matthias Weisserweisserm@arcor.de

arch/arm/lib/memcpy.S | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/arch/arm/lib/memcpy.S b/arch/arm/lib/memcpy.S index 3b5aeec..f655256 100644 --- a/arch/arm/lib/memcpy.S +++ b/arch/arm/lib/memcpy.S @@ -60,6 +60,9 @@ .globl memcpy memcpy:

• cmp	r0, r1
  

• moveq	pc, lr
  

• enter r4, lr

  subs r2, r2, #4

The standard clearly say to both memory regions should not overlap when memcpy() is used, so I would say this is the wrong place to fix that.

Regards,

Alexander