On Thu, 2022-05-19 at 14:58 +0800, Yong Wu wrote: > On Mon, 2022-05-16 at 22:16 +0800, yf.w...@mediatek.com wrote: > > From: Yunfei Wang <yf.w...@mediatek.com> > > > > Add the quirk IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT support, so that > > allows > > page table PA up to 35bit, not only in ZONE_DMA32. > > Comment why this is needed. > > e.g. For single normal zone. >
Hi Yong, There is no DMA32 zone in some mediatek smartphone chip for single normal zone. The level 1 and level 2 pgtable are both allocated in ZONE_DMA32, and may have two possible problem: 1.The level 2 pgtable is allocated in ZONE_DMA32 with atomic flag, and it may fail if ZONE_DMA32 memory is used out. 2.Single memory feature will make ZONE_DMA32 empty, and cause level 1 and level 2 pgtable PA more than 32bit. Solution: Add the quirk IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT support, so that level 1 and level 2 pgtable can support at most 35bit PA. I will update the commit message in next version. Thanks, Yunfei. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu