From mboxrd@z Thu Jan  1 00:00:00 1970
From: caglarakyuz@gmail.com (Caglar Akyuz)
Date: Tue, 19 Jan 2010 16:40:43 +0200
Subject: Kernel Start-up Time
In-Reply-To: <4B5591A4.2050807@l4dev.org>
References: <201001181010.01975.caglarakyuz@gmail.com>
	<4B5591A4.2050807@l4dev.org>
Message-ID: <201001191640.43715.caglarakyuz@gmail.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Tuesday 19 January 2010 01:04:04 pm Bahadir Balban wrote:
> Caglar Akyuz wrote:
> > Hello,
> >
> > While measuring Linux start-up time, I see that printing version string
> > in "start_kernel" takes ~1.3 seconds. I guess this is the time between
> > from "bootloader jumping to uImage" and "printing version string in
> > generic start_kernel code".
> >
> > Thanks,
> > Caglar
> >
> > _____________________________________________________________________
> >
> > [    4.700896] Starting kernel ...
> > [    4.702971]
> > [    5.966039] [    0.000000] Linux version
> > 2.6.30-davinci1-06079-g4e73fae-
> 
> Hi Caglar,
> 
> This sounds like the kernel decompression is taking time. Have you tried
> booting an uncompressed kernel? See if you can print on physical uart
> address from files under arch/arm/boot/compressed
> 
> Thanks,
> 

Hi,

My image was uncompressed already. However, I was fooled by the printk delays. 
Learning proper use of early printk solved the issue.

Thanks,
Caglar