[PATCH 00/03] ARM: shmobile: Use shmobile_init_delay() on r8a7791

Laurent Pinchart laurent.pinchart at ideasonboard.com
Mon May 12 13:00:08 PDT 2014


Hi Magnus,

On Monday 12 May 2014 08:25:08 Magnus Damm wrote:
> ARM: shmobile: Use shmobile_init_delay() on r8a7791
> 
> [PATCH 01/03] ARM: shmobile: Use r8a7791 DT CPU Frequency in common case
> [PATCH 02/03] ARM: shmobile: Use r8a7791 DT CPU Frequency for Koelsch
> [PATCH 03/03] ARM: shmobile: Remove unused r8a7791_init_early()
> 
> Convert r8a7791 to rely on shmobile_init_delay() instead of using a per-SoC
> delay setup function.

I'm afraid this patch set causes a boot time and CPU load regression on 
Koelsch. With Simon's latest devel branch which has the patches applied, the 
kernel boot time (using koelsch_defconfig) up to the point where the kernel 
tries to connect to the DHCP server is 17.898437s. The CPU load (as reported 
by top) on an idle system is then around 33%, spent in [kworker/0:1]. If I 
revert the patches the same time goes down to 1.921875s and the CPU load on an 
idle system is close to 0.

> Signed-off-by: Magnus Damm <damm+renesas at opensource.se>
> ---
> 
>  Written against renesas-devel-v3.15-rc5-20140511
> 
>  arch/arm/mach-shmobile/board-koelsch-reference.c |    2 +-
>  arch/arm/mach-shmobile/board-koelsch.c           |    2 +-
>  arch/arm/mach-shmobile/include/mach/r8a7791.h    |    1 -
>  arch/arm/mach-shmobile/setup-r8a7791.c           |    9 +--------
>  4 files changed, 3 insertions(+), 11 deletions(-)

-- 
Regards,

Laurent Pinchart




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