Existing exynos-iommu driver only supports SysMMU versions up to v5. But
it's pretty much ready for basic usage with SysMMU v7, only small
changes have to be done. As SysMMU version is tested dynamically (by
reading the corresponding register), there is no need to introduce new
compatible string.

One major change is that SysMMU v7 can have different register layouts:
  - with Virtual Machine support
  - without Virtual Machine support

That can be checked by reading the capability registers. In case the
SysMMU IP-core is VM-capable, the VM registers have to be used, and some
additional initialization is needed. That is the case on E850-96 board,
which non-secure SysMMU (v7.4) implements VM-capable register set.

The patch series was tested on E850-96 board. Because at the moment
there are no SysMMU users for that board, the testing was done using so
called "Emulated Translation" registers available on SysMMU v7. That
allows one to initiate the translation from CPU, by writing to those
registers, and then reading the corresponding TLB registers to find out
the translation result. The testing driver can be found in [1] tree.

[1] https://github.com/joe-skb7/linux/tree/e850-96-mainline-iommu

Sam Protsenko (4):
  iommu/exynos: Set correct dma mask for SysMMU v5+
  iommu/exynos: Check if SysMMU v7 has VM registers
  iommu/exynos: Use lookup based approach to access v7 registers
  iommu/exynos: Add minimal support for SysMMU v7 with VM registers

 drivers/iommu/exynos-iommu.c | 112 ++++++++++++++++++++++++++++++++---
 1 file changed, 104 insertions(+), 8 deletions(-)


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