Re: [PATCH V2 3/3] arm64: defconfig: Enable CRYPTO_DEV_FSL_CAAM

From: Horia Geanta
Date: Fri Dec 20 2019 - 03:07:40 EST


On 12/17/2019 8:25 PM, Fabio Estevam wrote:
> Hi Adam,
>
> On Tue, Dec 17, 2019 at 10:07 AM Adam Ford <aford173@xxxxxxxxx> wrote:
>
>> Out of curiosity, what is the rule for when things are 'm' vs 'y'?
>>
>> In the Code Aurora repo, it is set to 'y' and the mainline kernel for
>> the i.MX6/7, the imx_v6_v7_defconfig is also set to 'y' which is why I
>> used 'y' here.
>>
>> I can do a V3 to address the other items you noted, but I want to
>> understand the rules about the defconfig so I don't make the same
>> mistake again.
>
> In arch/arm64/configs/defconfig we try to select modules whenever possible.
>
> The exceptions are drivers that are vital for boot such as PMIC,
> pinctrl, clks, etc.
>
> The CAAM driver does not fall into this category, so selecting it as
> module is preferred here.
>
One comment here though.

CAAM's RNG is not "vital" for booting, but IIUC it would decrease the boot time
since it feeds the entropy pool through the hwrng interface.

Once RNG driver is fixed, would it be acceptable to add:
CONFIG_HW_RANDOM=y
CONFIG_CRYPTO_DEV_FSL_CAAM=y
in arm64 defconfig?

Thanks,
Horia