[PATCH v5 07/14] drivers: acpi: iort: add support for ARM SMMU platform devices creation

Hanjun Guo hanjun.guo at linaro.org
Tue Sep 13 01:48:15 PDT 2016


On 2016/9/13 16:24, Lorenzo Pieralisi wrote:
> On Tue, Sep 13, 2016 at 04:15:31PM +0800, Hanjun Guo wrote:
>
> [...]
>
>>>> +static acpi_status __init iort_match_iommu_callback(struct
>>>> acpi_iort_node *node,
>>>> +                            void *context)
>>>> +{
>>>> +    int ret;
>>>> +    struct fwnode_handle *fwnode;
>>>> +
>>>> +    fwnode = iort_get_fwnode(node);
>>>> +
>>>> +    if (!fwnode)
>>>> +        return AE_NOT_FOUND;
>>>> +
>>>> +    ret = iort_add_smmu_platform_device(fwnode, node);
>>>> +    if (ret) {
>>>> +        pr_err("Error in platform device creation\n");
>>>> +        return AE_ERROR;
>>>> +    }
>>>> +
>>>> +    return AE_OK;
>>>> +}
>>>> +
>>>> +static void __init iort_smmu_init(void)
>>>> +{
>>>> +    iort_scan_node(ACPI_IORT_NODE_SMMU, iort_match_iommu_callback,
>>>> NULL);
>>>> +    iort_scan_node(ACPI_IORT_NODE_SMMU_V3, iort_match_iommu_callback,
>>>> NULL);
>>>
>>> Since iort_scan_node() returns after the first successful match it finds,
>>> only the first SMMU_V3 in my IORT is being enumerated. I think you need
>>> to go back to the "iterator" like approach you had been using or make
>>> iort_match_iommu_callback() always return a non-AE_OK value so the scan
>>> continues and has a chance to visit all of the SMMU_V3 nodes.
>>
>> Please use the updated version of IORT patch (aka Tomasz's v11)
>> then things will work fine.
>
> Nate is right, I was too keen on using iort_scan_node(), it does
> not really work here (unless as he said I return a value !AE_OK in
> the callback, which is horrible), I reverted back to the iterator
> approach and I can push out a fixed up branch if useful before next
> posting.

Ah, sorry, I just noticed "the first SMMU_V3" which is pretty similar
with the second problem which is noticed by Nate...

Thanks
Hanjun




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