[PATCH v12 2/7] iommu/mediatek: Fix two IOMMU share pagetable issue
Alexandre Mergnat
amergnat at baylibre.com
Tue Jun 6 06:59:32 PDT 2023
On 02/06/2023 11:02, Yong Wu wrote:
> Prepare for mt8188 to fix a two IOMMU HWs share pagetable issue.
>
> We have two MM IOMMU HWs in mt8188, one is VPP-IOMMU, the other is
> VDO-IOMMU. The 2 MM IOMMU HWs share pagetable don't work in this case:
> a) VPP-IOMMU probe firstly.
> b) VDO-IOMMU probe.
> c) The master for VDO-IOMMU probe (means frstdata is vpp-iommu).
> d) The master in another domain probe. No matter it is vdo or vpp.
> Then it still create a new pagetable in step d). The problem is
> "frstdata->bank[0]->m4u_dom" was not initialized. Then when d) enter, it
> still create a new one.
>
> In this patch, we create a new variable "share_dom" for this share
> pgtable case, it should be helpful for readable. and put all the share
> pgtable logic in the mtk_iommu_domain_finalise.
>
> In mt8195, the master of VPP-IOMMU probes before than VDO-IOMMU
> from its dtsi node sequence, we don't see this issue in it. Prepare for
> mt8188.
Reviewed-by: Alexandre Mergnat <amergnat at baylibre.com>
--
Regards,
Alexandre
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