Re: [PATCH v3 3/5] arm: fiq: Replace default FIQ handler

From: Daniel Thompson
Date: Mon Sep 08 2014 - 11:57:09 EST


On 08/09/14 16:49, Nicolas Pitre wrote:
> On Mon, 8 Sep 2014, Daniel Thompson wrote:
>
>> +@
>> +@ Taking a FIQ in abort mode is similar to taking a FIQ in SVC mode
>> +@ and reuses the same macros. However in abort mode we must also
>> +@ save/restore lr_abt and spsr_abt to make nested aborts safe.
>> +@
>> + .align 5
>> +__fiq_abt:
>> + svc_entry 0, 0
>> +
>> + ARM( msr cpsr_c, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
>> + THUMB( mov r0, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
>> + THUMB( msr cpsr_c, r0 )
>> + mov r1, lr @ Save lr_abt
>> + mrs r2, spsr @ Save spsr_abt, abort is now safe
>> + ARM( msr cpsr_c, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
>> + THUMB( mov r0, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
>> + THUMB( msr cpsr_c, r0 )
>> + push {r1 - r2}
>
> stmfd sp!, {r1 - r2}
>
>> +
>> + sub r0, sp, #8 @ struct pt_regs *regs
>> + bl handle_fiq_as_nmi
>> +
>> + pop {r1 - r2}
>
> ldmfd sp!, {r1 - r2}
>
> ... so that old binutils we still accept to compile the kernel (in ARM
> mode) are happy.

Will do.


> Otherwise...
>
> Acked-by: Nicolas Pitre <nico@xxxxxxxxxx>

Thanks :-)

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