[PATCH v5 0/9] dmaengine: rcar-dmac: add iommu support for slave transfers

From: "Niklas Söderlund" <niklas.soderlund+renesas@ragnatech.se>
To: vinod.koul@intel.com, linux-renesas-soc@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org,
	iommu@lists.linux-foundation.org
Cc: robin.murphy@arm.com, laurent.pinchart@ideasonboard.com,
	geert+renesas@glider.be, linus.walleij@linaro.org,
	dan.j.williams@intel.com, arnd@arndb.de,
	linux-arch@vger.kernel.org,
	"Niklas Söderlund" <niklas.soderlund+renesas@ragnatech.se>
Subject: [PATCH v5 0/9] dmaengine: rcar-dmac: add iommu support for slave transfers
Date: Tue,  8 Mar 2016 03:42:45 +0100	[thread overview]
Message-ID: <1457404974-1800-1-git-send-email-niklas.soderlund+renesas@ragnatech.se> (raw)

Hi,

This series add iommu support to rcar-dmac. It's tested on Koelsch with
CONFIG_IPMMU_VMSA and by enabling the ipmmu_ds node in r8a7791.dtsi. I
verified operation by interacting with /dev/mmcblk1 and the serial
console which both are devices behind the iommu.

The series depends patch '[PATCH] dmaengine: use phys_addr_t for slave
configuration'.

* Changes since v4
- Move the mapping from phys_addr_t to dma_addr_t from slave_config to the
  prepare calls. This way we know the direction of the mapping and don't have
  to use DMA_BIDIRECTIONAL. Thanks Vinod for suggesting this.
- To be clear that the data type for slave addresses are changed add a patch
  that only changes the data type to phys_addr_t.
- Fixed up commit messages.

* Changes since v3
- Folded in a fix from Robin to his patch.
- Added a check to make sure dma_map_resource can not be used to map RAM as
  pointed out by Robin. I use BUG_ON to enforce this. It might not be the best
  method but I saw no other good way since DMA_ERROR_CODE might not be defined
  on all platforms.
- Added comment about that DTS changes will disable 2 DMA channels due to a HW
  (?) but in the DMAC.
- Dropped the use of dma_attrs, no longer needed.
- Collected Acked-by and Reviewed-by from Laurent.
- Various indentation fix ups.

* Changes since v2
- Drop patch to add dma_{map,unmap}_page_attrs.
- Add dma_{map,unmap}_resource to handle the mapping without involving a
  'struct page'. Thanks Laurent and Robin for pointing this out.
- Use size instead of address to keep track of if a mapping exist or not
  since addr == 0 is valid. Thanks Laurent.
- Pick up patch from Robin with Laurents ack (hope it's OK for me to
  attach the ack?) to add IOMMU_MMIO.
- Fix bug in rcar_dmac_device_config where the error check where
  inverted.
- Use DMA_BIDIRECTIONAL in rcar_dmac_device_config since we at that
  point can't be sure what direction the mapping is going to be used.

* Changes since v1
- Add and use a dma_{map,unmap}_page_attrs to be able to map the page
  using attributes DMA_ATTR_NO_KERNEL_MAPPING and
  DMA_ATTR_SKIP_CPU_SYNC. Thanks Laurent.
- Drop check if dmac is part of a iommu group or not, let the DMA
  mapping api handle it.
- Move slave configuration data around in rcar-dmac to avoid code
  duplication.
- Fix build issue reported by 'kbuild test robot' regarding phys_to_page
  not availability on some configurations.
- Add DT information for r8a7791.

* Changes since RFC
- Switch to use the dma-mapping api instead of using the iommu_map()
  directly. Turns out the dma-mapper is much smarter then me...
- Dropped the patch to expose domain->ops->pgsize_bitmap from within the
  iommu api.
- Dropped the patch showing how I tested the RFC.

Niklas Söderlund (8):
  dma-mapping: add {map,unmap}_resource to dma_map_ops
  dma-mapping: add dma_{map,unmap}_resource
  arm: dma-mapping: add {map,unmap}_resource for iommu ops
  dmaengine: rcar-dmac: slave address are physical
  dmaengine: rcar-dmac: group slave configuration
  dmaengine: rcar-dmac: add iommu support for slave transfers
  ARM: dts: r8a7790: add iommus to dmac0 and dmac1
  ARM: dts: r8a7791: add iommus to dmac0 and dmac1

Robin Murphy (1):
  iommu: Add MMIO mapping type

 arch/arm/boot/dts/r8a7790.dtsi |  30 +++++++++++
 arch/arm/boot/dts/r8a7791.dtsi |  30 +++++++++++
 arch/arm/mm/dma-mapping.c      |  63 ++++++++++++++++++++++
 drivers/dma/sh/rcar-dmac.c     | 116 +++++++++++++++++++++++++++++++++--------
 drivers/iommu/io-pgtable-arm.c |   9 +++-
 include/linux/dma-mapping.h    |  38 ++++++++++++++
 include/linux/iommu.h          |   1 +
 7 files changed, 263 insertions(+), 24 deletions(-)

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2.7.2