[PATCH] media: staging: ipu3: Enable IOVA API only when IOMMU support is enabled

[Yuehaibing]

On 2019/7/24 21:49, Robin Murphy wrote:
> On 24/07/2019 11:30, Sakari Ailus wrote:
>> Hi Yue,
>>
>> On Mon, Jul 22, 2019 at 09:47:49PM +0800, YueHaibing wrote:
>>> If IOMMU_SUPPORT is not set, ipu3 driver may select IOMMU_IOVA to m.
>>> But for many drivers, they use "select IOMMU_IOVA if IOMMU_SUPPORT"
>>> in the Kconfig, for example, CONFIG_TEGRA_VDE is set to y but IOMMU_IOVA
>>> is m, then the building fails like this:
>>>
>>> drivers/staging/media/tegra-vde/iommu.o: In function `tegra_vde_iommu_map':
>>> iommu.c:(.text+0x41): undefined reference to `alloc_iova'
>>> iommu.c:(.text+0x56): undefined reference to `__free_iova'
>>>
>>> Reported-by: Hulk Robot <hulkci at huawei.com>
>>> Fixes: 7fc7af649ca7 ("media: staging/intel-ipu3: Add imgu top level pci device driver")
>>> Signed-off-by: YueHaibing <yuehaibing at huawei.com>
>>> ---
>>>   drivers/staging/media/ipu3/Kconfig | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/staging/media/ipu3/Kconfig b/drivers/staging/media/ipu3/Kconfig
>>> index 4b51c67..b7df18f 100644
>>> --- a/drivers/staging/media/ipu3/Kconfig
>>> +++ b/drivers/staging/media/ipu3/Kconfig
>>> @@ -4,7 +4,7 @@ config VIDEO_IPU3_IMGU
>>>       depends on PCI && VIDEO_V4L2
>>>       depends on MEDIA_CONTROLLER && VIDEO_V4L2_SUBDEV_API
>>>       depends on X86
>>> -    select IOMMU_IOVA
>>> +    select IOMMU_IOVA if IOMMU_SUPPORT
>>
>> This doesn't seem right: the ipu3-cio2 driver needs IOMMU_IOVA
>> independently of IOMMU_SUPPORT.
>>
>> Looking at tegra-vde, it seems to depend on IOMMU_SUPPORT but that's not
>> declared in its Kconfig entry. I wonder if adding that would be the right
>> way to fix this.
>>
>> Cc'ing the IOMMU list.
> 
> Right, I also had the impression that we'd made the IOVA library completely standalone. And what does the IPU3 driver's Kconfig have to do with some *other* driver failing to link anyway?

Oh, I misunderstand that IOMMU_IOVA is depend on IOMMU_SUPPORT, thank you for clarification.

I will try to fix this in tegra-vde.

> 
> Robin.
> 
>>
>>>       select VIDEOBUF2_DMA_SG
>>>       help
>>>         This is the Video4Linux2 driver for Intel IPU3 image processing unit,
>>
> 
> .
>