Re: [PATCH v1 1/5] net/ark: update mpu code to match current hardware version

[Ferruh Yigit <ferruh.yigit@xilinx.com>]

On 5/6/2022 10:27 PM, Ed Czeck wrote:
> new version code
> remove device-level global operations
> remove ark_mpu_reset_stats function
> 

Hi Ed, please find a few comments inline.

Also I assume 'mpu' is an abbreviation, can you please document what it 
stands for in the commit log, like MPU (M.. P.. U..)?
And can you please make it uppercase in the commit title, also if you 
can add them to 'devtools/words-case.txt' (in a separate patch), it will 
be checked next time by './devtools/check-git-log.sh' script.
Same for all patches.

> Signed-off-by: Ed Czeck <ed.czeck@atomicrules.com>
> ---
>   drivers/net/ark/ark_ethdev.c    |  2 --
>   drivers/net/ark/ark_ethdev_rx.c |  4 ----
>   drivers/net/ark/ark_mpu.c       | 21 ++++-----------------
>   drivers/net/ark/ark_mpu.h       | 29 ++---------------------------
>   4 files changed, 6 insertions(+), 50 deletions(-)
> 

<...>

> @@ -24,10 +24,10 @@ ark_mpu_verify(struct ark_mpu_t *mpu, uint32_t obj_size)
>   {
>   	uint32_t version;
>   
> -	version = mpu->id.vernum & 0x0000fF00;
> -	if ((mpu->id.idnum != 0x2055504d) ||
> -	    (mpu->hw.obj_size != obj_size) ||
> -	    (version != 0x00003100)) {
> +	version = mpu->id.vernum;
> +	if (mpu->id.idnum != ARK_MPU_MODID ||
> +	    version != ARK_MPU_MODVER ||
> +	    mpu->hw.obj_size != obj_size) {

The driver will work with a specific version of the 'MPU'. So a device 
previously working with previous version of the driver, won't work 
anymore after this patch, and will be forced to a (FW/bitstream/?) update.
I am not sure how problematic is this from the stable release 
perspective. cc'ed maintainers.

But at least won't it be good to document this in release notes, and 
perhaps having a table in the driver documentation to list which DPDK 
version requires which HW version can be good, what do you think?