[PATCH v5 0/2] MTK Smart Device Gen1 NAND Driver
Jorge Ramirez-Ortiz
jorge.ramirez-ortiz at linaro.org
Tue Jun 14 08:50:49 PDT 2016
Fixes/Changes on v5 relative to:
--------------------------------
tree : https://github.com/bbrezillon/linux-0day
branch : nand/next
commit :
'commit "mtd: nand: sunxi: fix return value check..."'
Author: Wei Yongjun <yongjun_wei at trendmicro.com.cn>
Date: Mon Jun 13 14:27:18 2016 +0000
Patch v5
--------
mtd: mediatek: device tree bindings for MTK Smart Device Gen1 NAND
- remove unused property
mtd: mediatek: driver for MTK Smart Device Gen1 NAND
- clean up macros and clarify semantics.
- replace codec requests with operations.
- replace semaphore with mutex on ecc accesses.
- addtional comments to some functions.
- explicit error for 16bits buswidth (not supported).
- resolve endian issues.
- determine active ecc codec by register inspection.
Patch v4
--------
mtd: mediatek: device tree docs for MTK Smart Device Gen1 NAND
- nand-on-flash-bbt, nand-ecc-mode, nand-ecc-step-size and
nand-ecc-strength are now optional parameters
- spare-per-sector removed from DT settings.
- extend documentation.
mtd: mediatek: driver for MTK Smart Device Gen1 NAND
- rename functions (semantic issues).
- add lock to ECC engine.
- rework ECC interface (single enable/disable function).
- rework bad block mark (now stored in OOB).
- fix stat reporting.
- rework FDM calculation.
- handle optional DT settings (strength, mode, ecc step size).
- spare per sector clamped to valid register values (hw spec).
Patch v3
--------
mtd: mediatek: device tree docs for MTK Smart Device Gen1 NAND
- rename nandc (nand controller)
mtd: mediatek: driver for MTK Smart Device Gen1 NAND
- rename source and header files
- register definitions move to source files
- ecc interface dropped
- blank lines between functions (checkpatch.pl doesn't catch them)
- ecc_check function renamed ecc_get_stats
- ecc->dev assigned during probe()
- generic ecc control function replaced by individual functions
- required ecc parameters passed in ecc specific structures
- fix memory corruption (size 0 array)
- clarify nand offset/ptr function helpers (naming corrected)
- move ecc config call to select_chip()
- comment on hw issue workaround during read_byte
- implement write_buf
- remove switch_oob
- fix suspend/resume operation
- make nand-ecc-mode mandatory in device tree
RFC v2
------
mtd: mediatek: device tree docs for MTK Smart Device Gen1 NAND
- split nand flash interface and ecc engine
mtd: mediatek: driver for MTK Smart Device Gen1 NAND
- split host and ecc in two separate drivers.
- expose ecc layout through mtd_ooblayout_ops.
- fix wait loops.
- use device tree to describe ecc strength and ecc size.
- use device tree to describe CS.
- replace cmdfunc with cmd_ctrl.
- fix read byte interface.
dont enable controller in mt2701.dtsi
- requires additional device tree changes. This will be done in
the near future.
Overview:
=========
The following patch-set adds support for Mediatek's Smart Device
Gen1 NAND controller.
* Controller expected layout:
-----------------------------
The controller expects the OOB information relevant to each sector
within the page to follow immediately the data field.
For example for a 4KiB page with 1KiB sectors and 224B of OOB information,
the controller would expect the following layout.
-----------------------------------------------------
| 1KiB | 56B | 1KiB | 56B | 1KiB | 56B | 1KiB | 56B |
-----------------------------------------------------
This implies that the following actions are required:
- raw writes:
to match the controller expected layout, the driver uses the CPU and
a private bounce buffer to reassemble the page before the actual
writes.
- non raw writes:
ecc is hardware generated and data DMA'd in a single transfer.
Bad Block mark
==============
The bad block mark is stored in the OOB region (one byte)
Controller limitations:
=======================
* dma chaning not supported:
To guarantee that the pages corresponding to the buffers are contiguous
in memory the driver enables NAND_USE_BOUNCE_BUFFER.
* spare per sector: 16B to 128B
* sector sizes: 512B or 1024B
* programable page sizes: 512B, 2KB, 4KB, 8K, 16K
Tests:
======
* UBIFS support has been validated on 512MiB device (iozone, dd)
* All drivers/mtd/tests/* pass clean.
* Speed tests:
eraseblock write speed: 7563 KiB/s
eraseblock read speed: 10904 KiB/s
page write speed: 7497 KiB/s
page read speed: 10864 KiB/s
2 page write speed: 7527 KiB/s
2 page read speed: 10881 KiB/s
erase speed: 103157 KiB/s
2x multi-block erase speed: 357445 KiB/s
4x multi-block erase speed: 362944 KiB/s
8x multi-block erase speed: 363805 KiB/s
16x multi-block erase speed: 364237 KiB/s
32x multi-block erase speed: 364670 KiB/s
64x multi-block erase speed: 365104 KiB/s
Jorge Ramirez-Ortiz (2):
mtd: mediatek: device tree bindings for MTK Smart Device Gen1 NAND
mtd: mediatek: driver for MTK Smart Device Gen1 NAND
Documentation/devicetree/bindings/mtd/mtk-nand.txt | 160 +++
drivers/mtd/nand/Kconfig | 7 +
drivers/mtd/nand/Makefile | 1 +
drivers/mtd/nand/mtk_ecc.c | 528 +++++++
drivers/mtd/nand/mtk_ecc.h | 50 +
drivers/mtd/nand/mtk_nand.c | 1509 ++++++++++++++++++++
6 files changed, 2255 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mtd/mtk-nand.txt
create mode 100644 drivers/mtd/nand/mtk_ecc.c
create mode 100644 drivers/mtd/nand/mtk_ecc.h
create mode 100644 drivers/mtd/nand/mtk_nand.c
--
2.7.4
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