Re: [PATCH 2/2] iommu: calling pci_fixup_iommu in iommu_fwspec_init

Zhangfei Gao
2020-05-28T06:53:38Z

On 2020/5/27 下午5:01, Greg Kroah-Hartman wrote:
> On Tue, May 26, 2020 at 07:49:09PM +0800, Zhangfei Gao wrote:
>> Calling pci_fixup_iommu in iommu_fwspec_init, which alloc
>> iommu_fwnode. Some platform devices appear as PCI but are
>> actually on the AMBA bus, and they need fixup in
>> drivers/pci/quirks.c handling iommu_fwnode.
>> So calling pci_fixup_iommu after iommu_fwnode is allocated.
>>
>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
>> ---
>> drivers/iommu/iommu.c | 4 ++++
>> 1 file changed, 4 insertions(+)
>>
>> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
>> index 7b37542..fb84c42 100644
>> --- a/drivers/iommu/iommu.c
>> +++ b/drivers/iommu/iommu.c
>> @@ -2418,6 +2418,10 @@ int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
>> fwspec->iommu_fwnode = iommu_fwnode;
>> fwspec->ops = ops;
>> dev_iommu_fwspec_set(dev, fwspec);
>> +
>> + if (dev_is_pci(dev))
>> + pci_fixup_device(pci_fixup_iommu, to_pci_dev(dev));
> Why can't the caller do this as it "knows" it is a PCI device at that
> point in time, right?
Putting fixup here is because
1. iommu_fwspec has been allocated
2. iommu_fwspec_init will be called by of_pci_iommu_init and
iort_pci_iommu_init, covering both acpi and dt

Thanks