Re: [Qemu-arm] [Qemu-devel] [PATCH v9 12/14] hw/arm/virt: Add SMMUv3 to the virt board

[Peter Maydell]

On 12 March 2018 at 15:01, Auger Eric <address@hidden> wrote:
> Hi Peter,
>
> On 12/03/18 13:46, Peter Maydell wrote:
>> On 17 February 2018 at 18:46, Eric Auger <address@hidden> wrote:
>>> +    qemu_fdt_setprop(vms->fdt, node, "dma-coherent", NULL, 0);
>>
>> Is this definitely the right setting for dma-coherent? My (possibly
>> naive) thought is that for an emulated SMMU our page-table walks are
>> going to be coherent with the CPU's view.
>
> Indeed we add the dma-capable property to make the DMA ops of the SMMU
> cache coherent with the CPU. We pass NULL/O since there is just
> dma-coherent in the dt property. What am I missing?

My mistake, I thought this was the equivalent of "dma-coherent = 0;".

thanks
-- PMM