[PATCH v4 0/2] Add Unisoc IOMMU basic driver

[Chunyan Zhang]

From: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>

Changes since v3:
* Rebased on iommu/next, and fixed compile error reported by kernel test robot <lkp@xxxxxxxxx>;
* %s/iommu/IOMMU/ properly in the whole patchset.

Changes since v2:
* Added a WARN and return 0 if an invalid iova was passed to sprd_iommu_iova_to_phys();
* Changed the name of sprd_iommu_write();
* Revised CONFIG_SPRD_IOMMU help graph in Kconfig.
* Revised comments for the struct sprd_iommu_device;
* Converted to use "GPL" instread of "GPL v2", they are same as license-rules.rst shows.

Changes since v1:
* Fixed compile errors reported by kernel test robot <lkp@xxxxxxxxx>.
* Changed to use syscon to get mapped registers for iommu and media devices to avoid double map issue.
* Addressed Robin's comments:
- Added including offset in the returned physical address if the input virtual address isn't page-aligned;
- Added platform_device_put() after calling of_find_device_by_node();
- Removed iommu register offset from driver, it will be defined as the cell of DT reference to syscon phandle;
- Removed multi compatible strings which are not needed;
- Added comments for the function sprd_iommu_clk_enable();
- Added clocks property in bindings;
- Set device_driver.suppress_bind_attrs to disable unbind the devices via sysfs;
- A few trivial fixes.

Changes since RFC v2:
* Addressed Robin's comments:
- Add COMPILE_TEST support;
- Use DMA allocator for PTE;
- Revised to avoid resource leak issue;
- Added ->iotlb_sync implemented;
- Moved iommu group allocation to probe;
- Changed some function names to make them sprd specific;
* Added support for more iommu instance;

Changes since RFC v1:
* Rebased on v5.11-rc1;
* Changed sprd-iommu to tristate;
* Removed check for args_count of iommu OF node, since there's no args
  for sprd-iommu device node;
* Added another IP version (i.e. vau);
* Removed unnecessary configs selection from CONFIG_SPRD_IOMMU;
* Changed to get zeroed pages.

Chunyan Zhang (2):
  dt-bindings: iommu: add bindings for sprd IOMMU
  iommu: add Unisoc IOMMU basic driver

 .../devicetree/bindings/iommu/sprd,iommu.yaml |  72 +++
 drivers/iommu/Kconfig                         |  12 +
 drivers/iommu/Makefile                        |   1 +
 drivers/iommu/sprd-iommu.c                    | 599 ++++++++++++++++++
 4 files changed, 684 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iommu/sprd,iommu.yaml
 create mode 100644 drivers/iommu/sprd-iommu.c

-- 
2.25.1