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Message-ID: <8915e679-71b2-eef4-88d5-127bcc6cf990@arm.com>
Date:   Wed, 6 Jul 2022 11:54:27 +0100
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Subject: Re: [PATCH v2 09/14] iommu/ipmmu-vmsa: Clean up bus_set_iommu()
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To:     Alexey Kardashevskiy <aik@ozlabs.ru>, joro@8bytes.org,
        will@kernel.org
Cc:     jean-philippe@linaro.org, zhang.lyra@gmail.com,
        linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org,
        thierry.reding@gmail.com, gerald.schaefer@linux.ibm.com,
        linux-arm-kernel@lists.infradead.org
References: <cover.1650890638.git.robin.murphy@arm.com>
 <01a58dcc9c70836b7556d54dbdac6a340f206781.1650890638.git.robin.murphy@arm.com>
 <aef1d470-e8a0-4ba8-2a55-adf05b836684@ozlabs.ru>
From:   Robin Murphy <robin.murphy@arm.com>
In-Reply-To: <aef1d470-e8a0-4ba8-2a55-adf05b836684@ozlabs.ru>
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On 2022-07-06 09:38, Alexey Kardashevskiy wrote:
> 
> 
> On 28/04/2022 23:18, Robin Murphy wrote:
>> Stop calling bus_set_iommu() since it's now unnecessary. This also
>> leaves the custom initcall effectively doing nothing but register
>> the driver, which no longer needs to happen early either, so convert
>> it to builtin_platform_driver().
>>
>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>> ---
>>   drivers/iommu/ipmmu-vmsa.c | 35 +----------------------------------
>>   1 file changed, 1 insertion(+), 34 deletions(-)
>>
>> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
>> index 8fdb84b3642b..2549d32f0ddd 100644
>> --- a/drivers/iommu/ipmmu-vmsa.c
>> +++ b/drivers/iommu/ipmmu-vmsa.c
>> @@ -1090,11 +1090,6 @@ static int ipmmu_probe(struct platform_device 
>> *pdev)
>>           ret = iommu_device_register(&mmu->iommu, &ipmmu_ops, 
>> &pdev->dev);
>>           if (ret)
>>               return ret;
>> -
>> -#if defined(CONFIG_IOMMU_DMA)
>> -        if (!iommu_present(&platform_bus_type))
>> -            bus_set_iommu(&platform_bus_type, &ipmmu_ops);
>> -#endif
>>       }
>>       /*
> 
> The comment which starts here did not make it to the patch but it should 
> have as it mentions bus_set_iommu() which is gone by the end of the series.

Heh, busted! In fact I think the whole point of that comment stops being 
true, but I couldn't be bothered to reason about it since one of the 
next steps after this is to start ripping all the arm_iommu_* stuff out 
anyway.

> More general question/request - could you please include the exact sha1 
> the patchset is based on? It did not apply to any current trees and 
> while it was trivial, it was slightly annoying to resolve the conflicts 
> :)  Thanks,

v3 is based directly on 5.19-rc3:

https://lore.kernel.org/lkml/cover.1657034827.git.robin.murphy@arm.com/

And if it helps I have it on a branch here as well:

https://gitlab.arm.com/linux-arm/linux-rm/-/tree/bus-set-iommu-v3

Robin.