Re: [PATCH v7 28/28] sfc: support pio mapping based on cxl

[Alejandro Lucero Palau <alucerop@amd.com>]

On 12/11/24 02:39, Edward Cree wrote:
> On 09/12/2024 18:54, alejandro.lucero-palau@amd.com wrote:
>> From: Alejandro Lucero <alucerop@amd.com>
>>
>> With a device supporting CXL and successfully initialised, use the cxl
>> region to map the memory range and use this mapping for PIO buffers.
>>
>> Signed-off-by: Alejandro Lucero <alucerop@amd.com>
> Acked-by: Edward Cree <ecree.xilinx@gmail.com>
>
>> @@ -1263,8 +1281,25 @@ static int efx_ef10_dimension_resources(struct efx_nic *efx)
>>   	iounmap(efx->membase);
>>   	efx->membase = membase;
>>   
>> -	/* Set up the WC mapping if needed */
>> -	if (wc_mem_map_size) {
>> +	if (!wc_mem_map_size)
>> +		goto out;
> Maybe this label ought to be called something else; it's not really an
>   'early exit', it's a 'skip over mapping and linking PIO', which just
>   _happens_ to be almost the last thing in the function.


I do not know if I follow your point here. This was added following 
Martin's previous review for keeping the debugging when PIO is not needed.

It is formally skipping now because the change what I think is good for 
keeping indentation simpler with the additional conditional added.

Anyway, I can change the label to something like "out_through_debug 
"which adds, IMO, unnecessary name complexity. Just using "debug" could 
give the wrong idea ...

Any naming suggestion?


>> @@ -24,9 +24,10 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
>>   	DECLARE_BITMAP(expected, CXL_MAX_CAPS);
>>   	DECLARE_BITMAP(found, CXL_MAX_CAPS);
>>   	struct pci_dev *pci_dev;
>> +	resource_size_t max;
>>   	struct efx_cxl *cxl;
>>   	struct resource res;
>> -	resource_size_t max;
> Why does 'max' have to move?  Weird churn.


A previous version (not sure if an official one) had two resource_size_t 
variables defined, and I moved it there for preserving the reverse 
christmas tree, and when removed one it did not look bad.

I will remove the move.

Thanks!