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From:   Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date:   Sat, 31 Aug 2019 18:29:32 +0300
Message-ID: <CAKv+Gu8cph2ogmVO+SV7CQwtDL5QA7ZAdR6RBjdrXrQ9CrC6yg@mail.gmail.com>
Subject: Re: cbc mode broken in rk3288 driver
To:     Elon Zhang <zhangzj@rock-chips.com>
Cc:     "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" 
        <linux-crypto@vger.kernel.org>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        Eric Biggers <ebiggers@kernel.org>
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On Fri, 23 Aug 2019 at 11:21, Elon Zhang <zhangzj@rock-chips.com> wrote:
>
>
> On 8/23/2019 15:33, Ard Biesheuvel wrote:
> > On Fri, 23 Aug 2019 at 10:10, Elon Zhang <zhangzj@rock-chips.com> wrote:
> >> Hi Ard,
> >>
> >> I will try to fix this bug.
> > Good
> >
> >> Furthermore, I will submit a patch to  set
> >> crypto node default disable in rk3288.dtsi.
> >>
> > Please don't. The ecb mode works fine, and 'fixing' the DT only helps
> > if you use the one that ships with the kernel, which is not always the
> > case.
> >
> But crypto node default 'okay' in SoC dtsi is not good since not all
> boards need this
>
> hardware function. It is better that default 'disbale' in SoC dtsi and
> enabled in specific
>
> board dts.
>

It is not a property of the board whether the crypto accelerator is
needed or not, it is a property of the use case in which the board is
being put to use.

Pretending a h/w block does not exist just because the Linux driver is
broken is not the way to fix this. Disable the driver as long as it is
broken, and re-enable it once it is fixed. And please don't touch the
dts - it describes the hardware, not the software.