Re: [PATCH v4 1/2] ethdev: remove get_reg_length callback

[Zyta Szpak <zr@semihalf.com>]

OK

On 27.06.2016 12:46, Remy Horton wrote:
> Morning,
>
>
> On 23/06/2016 14:26, zr@semihalf.com wrote:
>> From: Zyta Szpak <zr@semihalf.com>
>>
>> Version 4 of fixing the assumption of that device registers
>> are always 32 bits long. rte_eth_dev_get_reg_length and
>> rte_eth_dev_get_reg_info callbacks did not provide register size
>> to the app in any way. It is needed to allocate proper number
>> of bytes before retrieving registers content with
>> rte_eth_dev_get_reg. This commit remove rte_eth_dev_get_reg_length
>> callback and adds width parameter to reg_info struct which makes
>> it possible to call rte_eth_dev_get_reg_info to get attributes
>> first. The drivers using this callback fill width and length
>> when call to function made with data=NULL.
>
> I think this would read better as a commit message:
>
> Removes hard-coded assumption that device registers are always 32 bits 
> wide. The rte_eth_dev_get_reg_length and rte_eth_dev_get_reg_info 
> callbacks did not provide register size to the app in any way, which 
> is needed to allocate correct number of bytes before retrieving 
> registers using rte_eth_dev_get_reg.
>
> This commit changes rte_eth_dev_get_reg_info so that it can be used to 
> retrieve both the number of registers and their width, and removes the 
> now-redundant rte_eth_dev_get_reg_length.
>
>
>> -/**
>> - * Retrieve device registers and register attributes
>> + * Retrieve device registers and register attributes (nb of regs and 
>> reg size)
>>   *
>>   * @param port_id
>>   *   The port identifier of the Ethernet device.
>
> Need detail regarding how *info->data affects function behaviour. 
> Something along the lines of:
>
> /**
>  * Retrieve device registers and register attributes (number of
>  * registers and register size)
>  *
>  * @param port_id
>  *   The port identifier of the Ethernet device.
>  * @param info
>  *   Pointer to rte_dev_reg_info structure to fill in. If info->data is
>  *   NULL the function fills in the width and length fields. If non-NULL
>  *   the registers are put into the buffer pointed at by the data field.
>
> Program code itself looks good to me.
>
> ..Remy