Re: [Qemu-devel] [PATCH v1 06/12] net: cadence_gem: Add support for selecting the DMA MemoryRegion

[Peter Maydell]

On 6 October 2018 at 00:14, Philippe Mathieu-Daudé <address@hidden> wrote:
> Hi Edgar,
>
> On 03/10/2018 17:07, Edgar E. Iglesias wrote:
>> From: "Edgar E. Iglesias" <address@hidden>
>>
>> Add support for selecting the Memory Region that the GEM
>> will do DMA to.

>> @@ -1500,6 +1506,13 @@ static void gem_realize(DeviceState *dev, Error 
>> **errp)
>>      CadenceGEMState *s = CADENCE_GEM(dev);
>>      int i;
>>
>> +    if (s->dma_mr) {
>> +        s->dma_as = g_malloc0(sizeof(AddressSpace));
>> +        address_space_init(s->dma_as, s->dma_mr, NULL);
>> +    } else {
>> +        s->dma_as = &address_space_memory;
>> +    }
>
> This is not the first time I see this if() block.
>
> Should we consider refactor it?

Given that there are only three users of the device in the tree,
I think the nicest cleanup would be to make those callers pass
in a suitable MemoryRegion (which could just be the system memory
MR), and make the "dma" property of the device mandatory to set.
We can do that as followup, though.

thanks
-- PMM