[v3,0/7] RZN1 DMA support

Message

Miquel Raynal Feb. 25, 2022, 11:23 a.m. UTC

Hello,

Here is a first series bringing DMA support to RZN1 platforms. I'm not a
DMA expert at all so criticism is welcome.

Soon a second series will come with changes made to the UART controller
driver, in order to interact with the RZN1 DMA controller.

Cheers,
Miquèl

Changes in v3:
* Added Reviewed-by tags.
* Exported the set_dmamux* symbol properly.
* Dropped a useless check in the probe and moved the sysctrl_priv
  assignation to the end of the probe.
* Renamed the dmamux driver
* Added a couple of missing MODULE_ macros in the dmamux driver.
* Decided to use a regular platform init call instead of the
  arch_initcall() initially proposed.
* s/%d/%u/ in printk's when appropriate.
* Used a hardcoded value instead of dmamux->dmac_requests when
  appropriate.
* Changed the variable name "master" to "dmac_idx" to be more
  descriptive.
* Dropped most of the of_* calls in favor of #define's.
* Fixed a typo.
* Exported two symbols from 8250_dma.c.

Changes in v2:
* Clarified that the 'fix' regarding non aligned reads would only apply
  to the DEV_TO_MEM case.
* Fix the DMA controller compatible string (copy-paste error).
* s/syscon/sysctrl/ as advised by Geert.
* Disabled irqs when taking the spinlock from the clocks driver.
* Moved the DMAMUX offset inside the driver.
* Removed extra commas.
* Improved the style as suggested by Andy.
* Removed a dupplicated check against the device node presence.
* Reduced the number of lines of code by using dev_err_probe().
* Created a Kconfig symbol for DMAMUX to fix the two robot reports
  received and be sure there was no useless overhead with other
  platforms.
* Exported the serial8250_{tx,rx}_dma() symbols.

Miquel Raynal (7):
  dt-bindings: dma: Introduce RZN1 dmamux bindings
  dt-bindings: dma: Introduce RZN1 DMA compatible
  soc: renesas: rzn1-sysc: Export function to set dmamux
  dma: dmamux: Introduce RZN1 DMA router support
  dma: dw: Add RZN1 compatible
  ARM: dts: r9a06g032: Add the two DMA nodes
  ARM: dts: r9a06g032: Describe the DMA router

 .../bindings/dma/renesas,rzn1-dmamux.yaml     |  42 +++++
 .../bindings/dma/snps,dma-spear1340.yaml      |   8 +-
 MAINTAINERS                                   |   1 +
 arch/arm/boot/dts/r9a06g032.dtsi              |  37 +++++
 drivers/clk/renesas/r9a06g032-clocks.c        |  35 +++-
 drivers/dma/dw/Kconfig                        |   8 +
 drivers/dma/dw/Makefile                       |   2 +
 drivers/dma/dw/platform.c                     |   1 +
 drivers/dma/dw/rzn1-dmamux.c                  | 152 ++++++++++++++++++
 include/linux/soc/renesas/r9a06g032-sysctrl.h |  11 ++
 10 files changed, 295 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/dma/renesas,rzn1-dmamux.yaml
 create mode 100644 drivers/dma/dw/rzn1-dmamux.c
 create mode 100644 include/linux/soc/renesas/r9a06g032-sysctrl.h