From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Date: Fri, 17 Dec 2010 14:52:49 -0600 Subject: [U-Boot] [PATCH] arm: Add armv6 and armv7 optimized swab functions In-Reply-To: <20101217202103.8351115192A@gemini.denx.de> References: <1292425994-24331-1-git-send-email-robherring2@gmail.com> <20101217202103.8351115192A@gemini.denx.de> Message-ID: <4D0BCDA1.2000907@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Wolfgang, On 12/17/2010 02:21 PM, Wolfgang Denk wrote: > Dear Rob Herring, > > In message<1292425994-24331-1-git-send-email-robherring2@gmail.com> you wrote: >> From: Rob Herring >> >> swab functions are heavily used by FDT code, so enable >> optimized assembly code for ARMv6 and later. >> >> Signed-off-by: Rob Herring >> --- >> arch/arm/include/asm/byteorder.h | 16 ++++++++++++++++ >> 1 files changed, 16 insertions(+), 0 deletions(-) > > Do you have any numbers if this changes gives any measurable > improvement? I have an instruction trace capture and see repeated calls to swab32 by the fdt code. It's an obvious low hanging fruit. The boot time for device tree vs. non-device tree is noticeably longer, but I don't have any formal measurements. Rob