[PATCH 0/7] CMA & device tree, another approach

Marek Szyprowski m.szyprowski at samsung.com
Tue Aug 26 05:09:41 PDT 2014


Hello,

This is another approach to finish support for reserved memory regions
defined in device tree. Previous attempts 
(http://lists.linaro.org/pipermail/linaro-mm-sig/2014-February/003738.html
and https://lkml.org/lkml/2014/7/14/108) ended in merging parts of the
code and documentation. Merged patches allow to reserve memory, but
there is still no reserved memory drivers nor any code that actually
uses reserved memory regions.

The final conclusion from the above mentioned threads is that there is
no automated reserved memory initialization. All drivers that want to
use reserved memory, should initialize it on their own.

This patch series provides two driver for reserved memory regions (one
based on CMA and one based on dma_coherent allocator). The main
improvement comparing to the previous version is removal of automated
reserved memory for every device and support for named memory regions.

Support for more than one reserved memory region can be considered as a
separate DMA address space, so support for more than one region per
device has been implemented the same way as support for separate IO/DMA
address spaces in my Exynos IOMMU dma-mapping proposal:
http://thread.gmane.org/gmane.linux.kernel.samsung-soc/36079

Best regards
Marek Szyprowski
Samsung R&D Institute Poland

Changes since '[PATCH v2 RESEND 0/4] CMA & device tree, once again' version:
(https://lkml.org/lkml/2014/7/14/108)
- added return error value to of_reserved_mem_device_init()
- added support for named memory regions (so more than one region can be
  defined per device)
- added usage example - converted custom reserved memory code used by
  s5p-mfc driver to the generic reserved memory handling code

Patch summary:

Marek Szyprowski (7):
  drivers: of: add return value to of_reserved_mem_device_init
  drivers: of: add support for named memory regions
  drivers: dma-coherent: add initialization from device tree
  drivers: dma-contiguous: add initialization from device tree
  media: s5p-mfc: replace custom reserved memory init code with generic
    one
  ARM: Exynos: convert MFC to generic reserved memory bindings
  ARM: DTS: exynos4412-odroid*: enable MFC device

 .../devicetree/bindings/media/s5p-mfc.txt          |  16 +--
 .../bindings/reserved-memory/reserved-memory.txt   |   6 +-
 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/exynos5420-arndale-octa.dts      |  22 +++-
 arch/arm/boot/dts/exynos5420-smdk5420.dts          |  22 +++-
 arch/arm/mach-exynos/exynos.c                      |  18 ---
 arch/arm/mach-exynos/mfc.h                         |  16 ---
 arch/arm/plat-samsung/Kconfig                      |   5 -
 arch/arm/plat-samsung/Makefile                     |   1 -
 arch/arm/plat-samsung/s5p-dev-mfc.c                |  94 --------------
 drivers/base/dma-coherent.c                        | 138 ++++++++++++++++++---
 drivers/base/dma-contiguous.c                      |  71 +++++++++++
 drivers/media/platform/s5p-mfc/s5p_mfc.c           | 102 ++++++---------
 drivers/of/of_reserved_mem.c                       | 102 ++++++++++-----
 include/linux/cma.h                                |   3 +
 include/linux/of_reserved_mem.h                    |   9 +-
 mm/cma.c                                           |  62 +++++++--
 23 files changed, 552 insertions(+), 291 deletions(-)
 delete mode 100644 arch/arm/mach-exynos/mfc.h
 delete mode 100644 arch/arm/plat-samsung/s5p-dev-mfc.c

-- 
1.9.2




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