Hi,
We've had for quite some time to hack around in our drivers to take into
account the fact that our DMA accesses are not done through the parent
node, but through another bus with a different mapping than the CPU for the
RAM (0 instead of 0x40000000 for most SoCs).
After some discussion after the submission of a camera device suffering of
the same hacks, I've decided to put together a serie that introduce a
special interconnect name called "dma" that that allows to express the DMA
relationship between a master and its bus, even if they are not direct
parents in the DT.
Let me know what you think,
Maxime
Changes from v4:
- Fixed the commit logs that had some leftovers from earlier versions
- Removed spurious whitespaces
- Added tags
- Rebased on next
Changes from v3:
- Rebased on top of current next
- Use a function pointer instead of the parent device node to fix the
recursive cases
- Fix the usage of the device_node index in __of_get_dma_parent
- Refer to the DT Specification for dma-ranges in the MBUS binding
- Used dma-mem as the property instead of dma
Changes from v2:
- Rewrite commit logs still mentionning dma-parent
- Removed dma-parent-cells left over in the binding example
- Removed dma-parent still being mentionned in comments
Changes from v1:
- Change to use the now merged interconnect bindings
- Move the DMA parent retrieval logic to its own function
- Rebase on top of 5.0
Maxime Ripard (7):
dt-bindings: interconnect: Add a dma interconnect name
dt-bindings: bus: Add binding for the Allwinner MBUS controller
of: address: Retrieve a parent through a callback in __of_translate_address
of: address: Add support for the parent DMA bus
drm/sun4i: Rely on dma interconnect for our RAM offset
clk: sunxi-ng: sun5i: Export the MBUS clock
ARM: dts: sun5i: Add the MBUS controller
Documentation/devicetree/bindings/arm/sunxi/sunxi-mbus.txt | 36 ++++++-
Documentation/devicetree/bindings/interconnect/interconnect.txt | 4 +-
arch/arm/boot/dts/sun5i.dtsi | 13 ++-
drivers/clk/sunxi-ng/ccu-sun5i.h | 4 +-
drivers/gpu/drm/sun4i/sun4i_backend.c | 28 +++--
drivers/of/address.c | 40 +++++--
include/dt-bindings/clock/sun5i-ccu.h | 2 +-
7 files changed, 109 insertions(+), 18 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/sunxi/sunxi-mbus.txt
base-commit: e3ecb83ee707a3b2a4d12e19509ecbda7f793cc2
--
git-series 0.9.1
