Build error in torvalds kernel 3.11 for omap2plus

[Guenter Roeck]

On 09/09/2013 03:51 AM, Russell King - ARM Linux wrote:
> On Sun, Sep 08, 2013 at 10:16:14AM -0700, Guenter Roeck wrote:
>> Since we are at it:
>>
>> Build reference: v3.11-7887-gb409624
>>
>> Building arm:defconfig ... passed
>> Building arm:allmodconfig ... failed
>> --------------
>> Error log:
>> arch/arm/mach-cns3xxx/pcie.c: In function 'cns3xxx_pcie_hw_init':
>> arch/arm/mach-cns3xxx/pcie.c:350:1: warning: the frame size of 1064 bytes is larger than 1024 bytes [-Wframe-larger-than=]
>> arch/arm/kernel/return_address.c:63:2: warning: #warning "TODO: return_address should use unwind tables" [-Wcpp]
>> arch/arm/kernel/return_address.c:63:2: warning: #warning "TODO: return_address should use unwind tables" [-Wcpp]
>> /tmp/cce439dZ.s: Assembler messages:
>> /tmp/cce439dZ.s:506: Error: selected processor does not support ARM mode `isb '
>> /tmp/cce439dZ.s:512: Error: selected processor does not support ARM mode `isb '
>> /tmp/cce439dZ.s:513: Error: selected processor does not support ARM mode `dsb '
>> /tmp/cce439dZ.s:583: Error: selected processor does not support ARM mode `isb '
>> /tmp/cce439dZ.s:589: Error: selected processor does not support ARM mode `isb '
>> /tmp/cce439dZ.s:590: Error: selected processor does not support ARM mode `dsb '
>> make[1]: *** [arch/arm/mach-vexpress/dcscb.o] Error 1
>> make: *** [arch/arm/mach-vexpress] Error 2
>> make: *** Waiting for unfinished jobs....
>> --------------
>>
>> Any solution for this one ? omap2plus passes for me.
>>
>> gcc version used is "arm-poky-linux-gnueabi-gcc (GCC) 4.7.2" from poky 1.3.
>
> That's due to:
>
> commit e8f9bb1bd6bb93fff773345cc54c42585e0e3ece
> Author: Nicolas Pitre <nicolas.pitre at linaro.org>
> Date:   Tue Jul 16 20:59:53 2013 -0400
>
>      ARM: vexpress/dcscb: fix cache disabling sequences
>
>      Unlike real A15/A7's, the RTSM simulation doesn't appear to hit the
>      cache when the CTRL.C bit is cleared.  Let's ensure there is no memory
>      access within the disable and flush cache sequence, including to the
>      stack.
>
>      Signed-off-by: Nicolas Pitre <nico at linaro.org>
>
> which introduces some 'isb' and 'dsb' instructions which are not
> available on ARMv6 CPUs - however, their 'mcr' equivalents are.
>
> Either dcscb needs to be built with an -march=armv7 override, or
> they need to use the mcr equivalent instructions.
>

Well, I hope it will get fixed one way or another.
I don't know enough about arm to fix it myself.

Guenter