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[v3,0/6] mtd: rawnand: add NVIDIA Tegra NAND flash support

Message ID 20180531221637.6017-1-stefan@agner.ch
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Series mtd: rawnand: add NVIDIA Tegra NAND flash support | expand

Message

Stefan Agner May 31, 2018, 10:16 p.m. UTC 
This third revision is again a rather major overhaul. The driver
is now able to select a sensible ECC strenght automatically.

Review of the timing code uncovered few issues. Fixing them lead to
a tighter timing which lead to a performance increase of about 35%.
The in kernel speed test measures 11770/15058 KiB/s write/read speed.

Still open is the OOB layout discrepancy issue:
When using HW BCH support, the location of the ECC bytes changes
depending on whether extra OOB bytes (tag data) are transmitted or
not... Writing/Reading should always be with tag enabled or always
without. I am not sure how to solve this correctly, maybe disallow
using OOB data with HW ECC completely? Or just leave as is?

--
Stefan

Changes since v1:
- Split controller and NAND chip structure
- Add BCH support
- Allow to select algorithm and strength using device tree
- Improve HW ECC error reporting and use DEC_STATUS_BUF only
- Use SPDX license identifier
- Use per algorithm mtd_ooblayout_ops
- Use setup_data_interface callback for NAND timing configuration

Changes since v2:
- Set clock rate using assigned-clocks
- Use BIT() macro
- Fix and improve timing calculation
- Improve ECC error handling
- Store OOB layout for tag area in Tegra chip structure
- Update/fix bindings
- Use more specific variable names (replace "value")
- Introduce nand-is-boot-medium
- Choose sensible ECC strenght automatically
- Use wait_for_completion_timeout
- Print register dump on completion timeout
- Unify tegra_nand_(read|write)_page in tegra_nand_page_xfer

Lucas Stach (2):
  ARM: dts: tegra: add Tegra20 NAND flash controller node
  ARM: dts: tegra: enable NAND flash on Colibri T20

Stefan Agner (4):
  mtd: rawnand: add Reed-Solomon error correction algorithm
  mtd: rawnand: add an option to specify NAND chip as a boot device
  mtd: rawnand: tegra: add devicetree binding
  mtd: rawnand: add NVIDIA Tegra NAND Flash controller driver

 .../devicetree/bindings/mtd/nand.txt          |    4 +
 .../bindings/mtd/nvidia-tegra20-nand.txt      |   64 +
 MAINTAINERS                                   |    7 +
 arch/arm/boot/dts/tegra20-colibri-512.dtsi    |   16 +
 arch/arm/boot/dts/tegra20.dtsi                |   15 +
 drivers/mtd/nand/raw/Kconfig                  |    6 +
 drivers/mtd/nand/raw/Makefile                 |    1 +
 drivers/mtd/nand/raw/nand_base.c              |    4 +
 drivers/mtd/nand/raw/tegra_nand.c             | 1143 +++++++++++++++++
 include/linux/mtd/rawnand.h                   |    7 +
 10 files changed, 1267 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/nvidia-tegra20-nand.txt
 create mode 100644 drivers/mtd/nand/raw/tegra_nand.c