[PATCH v6 0/2] memory: add Atmel EBI (External Bus Interface) driver

Boris Brezillon boris.brezillon at free-electrons.com
Wed Apr 27 07:35:52 PDT 2016


The EBI (External Bus Interface) is used to access external peripherals
(NOR, SRAM, NAND, and other specific devices like ethernet controllers).
Each device is assigned a CS line and an address range and can have its
own configuration (timings, access mode, bus width, ...).
This driver provides a generic DT binding to configure a device according
to its requirements.
For specific device controllers (like the NAND one) the SMC timings
should be configured by the controller driver through the matrix and
smc syscon regmaps (or maybe we should provide an API for that?).

Changes since v5:
- remove the "atmel,specialized-logic" property: now all devices are
  are attached to the SMC logic by default, and specialized drivers
  (like the NAND controller one), should change this configuration
  manually.
- provide hardware readout to allow partial config description.
  This is mainly here to keep existing platforms (where everything
  is configured by the bootloader/bootstrap) in working state.
- rename "atmel,tdf-optimized" into "atmel,tdf-mode" and switch from
  a boolean to string property to properly support partial config

Changes since v4:
- fix inconsistencies in SMC and MATRIX registers definition
- add missing compatible strings for at91sam9rl SoC
- fix DT bindings documentation
- replace "atmel,generic-dev" property by "atmel,specialized-logic"

Changes since v3:
- added AT91_MATRIX_USBPUCR_PUON definition
- removed useless macros (those directly returning SoC specific register
  offsets)
- use syscon_regmap_lookup_by_phandle instead of of_parse_phandle +
  syscon_node_to_regmap
- drop AT91_EBICSA_REGFIELD and AT91_MULTI_EBICSA_REGFIELD macros

Changes since v2:
- minor fixes int DT bindings doc
- fix SMC macros
- make use of SMC macros defined in include/linux/mfd/syscon/atmel-smc.h

Changes since v1:
- almost everything :-)

Boris Brezillon (2):
  memory: add Atmel EBI (External Bus Interface) driver
  memory: atmel-ebi: add DT bindings documentation

 .../bindings/memory-controllers/atmel,ebi.txt      | 146 +++++
 drivers/memory/Kconfig                             |  11 +
 drivers/memory/Makefile                            |   1 +
 drivers/memory/atmel-ebi.c                         | 662 +++++++++++++++++++++
 4 files changed, 820 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/memory-controllers/atmel,ebi.txt
 create mode 100644 drivers/memory/atmel-ebi.c

-- 
2.7.4




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