[PATCH 3/3] hash: Allow for SHA512 hardware implementations

[Heinrich Schuchardt]

On 12.05.21 18:05, Simon Glass wrote:
> Hi Heinrich,
>
> On Wed, 12 May 2021 at 10:01, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>>
>> On 17.02.21 04:20, Joel Stanley wrote:
>>> Similar to support for SHA1 and SHA256, allow the use of hardware hashing
>>> engine by enabling the algorithm and setting  CONFIG_SHA_HW_ACCEL /
>>> CONFIG_SHA_PROG_HW_ACCEL.
>>>
>>> Signed-off-by: Joel Stanley <joel at jms.id.au>
>>
>> This merged patch leads to errors compiling the EFI TCG2 protocol on
>> boards with CONFIG_SHA_HW_ACCEL.
>>
>> There is not as single implementation of hw_sha384 and hw_sha512. You
>> could only use CONFIG_SHA_HW_ACCEL for selecting these functions if
>> these were implemented for *all* boards with CONFIG_SHA_HW_ACCEL=y. But
>> this will never happen.
>>
>> *This patch needs to be reverted.*
>>
>> Why do we have CONFIG_SHA_HW_ACCEL at all and don't use weak functions
>> instead?
>
> This is all a mess. We should not use weak functions IMO, but instead
> have a driver interface, like we do with filesystems.
>
> Part of the challenge is the need to keep code size small for
> platforms that only need one algorithm.

If a function is not referenced, the linker will eliminate it. But with
a driver interface every function in the interface is referenced.

Best regards

Heinrich