Re: [PATCH 1/9] arm: select different compiler flags for ARM CortexM3

From: Paul Osmialowski
Date: Wed Jun 24 2015 - 00:50:39 EST


Hi Russell,

Thanks for the input. Seems like I trusted get_maintainer.pl blindly and wasn't selective - it resulted in recipient list much too long.

As for this patch, I think I went too far with adding it. The board boots without it properly, and since it covers more general Cortex-M related problems I guess it should be excluded from next iteration of the whole patchset.

The problems it adresses may still required further discussion, but I think it should not block the whole thing.

On Tue, 23 Jun 2015, Russell King - ARM Linux wrote:

On Tue, Jun 23, 2015 at 11:19:39PM +0200, Paul Osmialowski wrote:
This one is inspired by two commits published on Emcraft git repo:

https://github.com/EmcraftSystems/linux-emcraft.git

1) 6302b692f570ff9d5645a6e72c11f87b0c1aa409
RT #62654. Fixed kernel crashes while running httpd by enabling
"-mfix-cortex-m3-ldrd" compiler option, which prevents compiler from
generating code like 'ldrd Ra, Rb, [Ra, #Imm]' - according to the 602117
Cortex-M3 Errata it may result in incorrect base register when interrupted
or faulted.

by: Yuri Tikhonov <yur@xxxxxxxxxxx>

2) 359d3cda84c01c0f3fae1a519b97a31f318f57ab
RT #62654. Removed "--march=..." leaving only "-mcpu=cortex-m3" to make
sure only the correct instructions will be generated.

by: Sergei Poselenov <sposelenov@xxxxxxxxxxx>

I reworked these patches to make them less intrusive.

Signed-off-by: Paul Osmialowski <pawelo@xxxxxxxxxxx>

NAK.

The EFM32 code already added core support for Cortex-M3 cores, under
the symbol CPU_V7M. Rather than implementing a whole new set of
Cortex-M3 support alongside the existing code, please work with the
EFM32 maintainer (Uwe Kleine-König) to come up with a common set of
core changes that you can all agree on for Cortex-M3.

Please also try to be a little smarter with whom you're sending your
patches to, the Cc list looks to be excessively long - having soo many
recipients on your message is a good way to get your message rejected
by mailing lists as spam.

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