[PATCH v3 0/7] Exynos: MFC driver: reserved memory cleanup and IOMMU support

[Marek Szyprowski <m.szyprowski@samsung.com>]

Hello,

This patchset finally perform cleanup of custom code in s5p-mfc codec
driver. The first part is removal of custom, driver specific code for
intializing and handling of reserved memory. Instead, a generic code for
reserved memory regions is used. Then, once it is done, the proper setup
of DMA parameters (max segment size) is applied for all multimedia
devices found on Exynos SoCs to let them properly handle shared buffers
mapped into contiguous DMA address space. The last patch adds support
for IOMMU to MFC driver. Some additional code is needed because of
specific requirements of MFC device firmware (see patch 7 for more
details). When no IOMMU is available, the code fallbacks to generic
reserved memory regions.

After applying this patchset, MFC device works correctly when IOMMU is
either enabled or disabled.

Patches have been tested on top of linux-next from 20151207. I would
prefer to merge patches 1-2 via Samsung tree and patches 3-7 via media
tree (there are no compile-time dependencies between patches 1-2 and
3-7). Patches have been tested on Odroid U3 (Exynos 4412 based) and
Odroid XU3 (Exynos 5422 based) boards.

Best regards
Marek Szyprowski
Samsung R&D Institute Poland


Changelog:
v3:
- fixed issues pointed by Laurent Pinchart:
  - added documentation to memory-region-names property,
  - changed devm_kzalloc to kzalloc in vb2_dma_contig_set_max_seg_size() to
    avoid access to freed memory after reloading driver module
- unified odroid mfc reserved memory configuration with other Exynos4 boards

v2: http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/97025
- reworked of_reserved_mem_init* functions on request from Rob Herring,
  added separate index and name based selection of reserved region
- adapted for of_reserved_mem_init* related changes

v1: https://www.mail-archive.com/linux-media@vger.kernel.org/msg94100.html
- initial version of another approach for this problem, rewrote driver code
  for new reserved memory bindings, which finally have been merged some
  time ago

v0: http://lists.infradead.org/pipermail/linux-arm-kernel/2013-August/189259.html
- old patchset solving the same problem, abandoned due to other tasks
  and long time of merging reserved memory bindings and support code for
  it

Patch summary:

Marek Szyprowski (7):
  ARM: Exynos: convert MFC device to generic reserved memory bindings
  ARM: dts: exynos4412-odroid*: enable MFC device
  of: reserved_mem: add support for named reserved mem nodes
  media: vb2-dma-contig: add helper for setting dma max seg size
  media: set proper max seg size for devices on Exynos SoCs
  media: s5p-mfc: replace custom reserved memory init code with generic
    one
  media: s5p-mfc: add iommu support

 .../devicetree/bindings/media/s5p-mfc.txt          |  16 +--
 .../bindings/reserved-memory/reserved-memory.txt   |   2 +
 .../devicetree/bindings/resource-names.txt         |   1 +
 arch/arm/boot/dts/exynos4210-origen.dts            |  22 ++-
 arch/arm/boot/dts/exynos4210-smdkv310.dts          |  22 ++-
 arch/arm/boot/dts/exynos4412-odroid-common.dtsi    |  24 ++++
 arch/arm/boot/dts/exynos4412-origen.dts            |  22 ++-
 arch/arm/boot/dts/exynos4412-smdk4412.dts          |  22 ++-
 arch/arm/boot/dts/exynos5250-arndale.dts           |  22 ++-
 arch/arm/boot/dts/exynos5250-smdk5250.dts          |  22 ++-
 arch/arm/boot/dts/exynos5250-spring.dts            |  22 ++-
 arch/arm/boot/dts/exynos5420-arndale-octa.dts      |  22 ++-
 arch/arm/boot/dts/exynos5420-smdk5420.dts          |  22 ++-
 arch/arm/boot/dts/exynos5422-odroidxu3-common.dtsi |  22 ++-
 arch/arm/mach-exynos/Makefile                      |   2 -
 arch/arm/mach-exynos/exynos.c                      |  19 ---
 arch/arm/mach-exynos/mfc.h                         |  16 ---
 arch/arm/mach-exynos/s5p-dev-mfc.c                 |  94 -------------
 drivers/media/platform/exynos-gsc/gsc-core.c       |   1 +
 drivers/media/platform/exynos4-is/fimc-core.c      |   1 +
 drivers/media/platform/exynos4-is/fimc-is.c        |   1 +
 drivers/media/platform/exynos4-is/fimc-lite.c      |   1 +
 drivers/media/platform/s5p-g2d/g2d.c               |   1 +
 drivers/media/platform/s5p-jpeg/jpeg-core.c        |   1 +
 drivers/media/platform/s5p-mfc/s5p_mfc.c           | 153 ++++++++++++---------
 drivers/media/platform/s5p-mfc/s5p_mfc_iommu.h     |  79 +++++++++++
 drivers/media/platform/s5p-tv/mixer_video.c        |   1 +
 drivers/media/v4l2-core/videobuf2-dma-contig.c     |  14 ++
 drivers/of/of_reserved_mem.c                       | 104 +++++++++++---
 include/linux/of_reserved_mem.h                    |  31 ++++-
 include/media/videobuf2-dma-contig.h               |   1 +
 31 files changed, 535 insertions(+), 248 deletions(-)
 delete mode 100644 arch/arm/mach-exynos/mfc.h
 delete mode 100644 arch/arm/mach-exynos/s5p-dev-mfc.c
 create mode 100644 drivers/media/platform/s5p-mfc/s5p_mfc_iommu.h

-- 
1.9.2