[PATCH v2 13/14] powerpc/pseries/iommu: Make use of DDW for indirect mapping

Alexey Kardashevskiy aik at ozlabs.ru
Tue Apr 13 17:18:56 AEST 2021



On 13/04/2021 15:49, Leonardo Bras wrote:
> Thanks for the feedback!
> 
> On Tue, 2020-09-29 at 13:56 +1000, Alexey Kardashevskiy wrote:
>>> -static bool find_existing_ddw(struct device_node *pdn, u64 *dma_addr)
>>> +static phys_addr_t ddw_memory_hotplug_max(void)
>>
>>
>> Please, forward declaration or a separate patch; this creates
>> unnecessary noise to the actual change.
>>
> 
> Sure, done!
> 
>>
>>> +		_iommu_table_setparms(tbl, pci->phb->bus->number, create.liobn, win_addr,
>>> +				      1UL << len, page_shift, 0, &iommu_table_lpar_multi_ops);
>>> +		iommu_init_table(tbl, pci->phb->node, 0, 0);
>>
>>
>> It is 0,0 only if win_addr>0 which is not the QEMU case.
>>
> 
> Oh, ok.
> I previously though it was ok to use 0,0 here as any other usage in
> this file was also 0,0.
> 
> What should I use to get the correct parameters? Use the previous tbl
> it_reserved_start and tbl->it_reserved_end is enough?

depends on whether you carry reserved start/end even if they are outside 
of the dma window.


-- 
Alexey


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