Introduction
This page gives an overview of nandps driver which is available as part of the Xilinx Vivado and SDK distribution.
Source path for the driver:
https://github.com/Xilinx/embeddedsw/tree/master/XilinxProcessorIPLib/drivers/nandps
Driver source code is organized into different folders. Below diagram shows the nandpsu driver source organization
nandps
|
-- Doc - Provides the API and data structure details
|
- Examples - Reference application to show how to use the driver APIs and calling sequence
|
- Source - Driver source files
Features Supported
Controller Features:
- ONFI 1.0 compatible
- upto 1GB device
- 8/16-bit IO width with a single chip select
- 16-word read/write FIFOs
- 8-word command FIFO
- Programmable IO Cycle timing
- 1-bit ECC hardware with sw assist
- Asynchronous memory operating mode
Driver Features:
- Supports only the mandatory ONFI 1.0 commands. i.e Reset, Read status, Read ID, Read Parameter Page, Read Page, Program Page, Erase Block, Set/Get Features
- supports page cache read operations
- Support BBT management
- Support for ondie ecc devices
Bad Block management
As part of the bbt management, driver reserves the last 4 blocks of the flash device for storing the bbt information. bbt management is similar to the Linux except the offset of storing the BBT signature land version location and also the locations reserved for storing the ecc information.Known issues and Limitations
- Driver supports polled mode only
- No support for interleaved and optional 1.0 commands
ChangeLog
2016.3
- None
2016.4
- None
2017.1
- None
2017.2
- None
2017.3
- None
2017.4
- None
2018.1
- None
2018.2
- None
2018.3
- Summary
- Fix incorrect BBT write
- Commit
- Summary
2019.1
- None
2019.2
- None
2020.1
- None
Test cases
Nandps example:
https://github.com/Xilinx/embeddedsw/blob/master/XilinxProcessorIPLib/drivers/nandps/examples/xnandps_example.c
It verifies the nand data integrity by programing the known data pattern and verify the same by reading the data back.
In this process erase, program, read, read ID, Read Parameter Page, Reset, read status, get/set features and bbt management are covered
Output:
Nand Flash Read Write Example Test Successfully ran Nand Flash Read Write Example Tes |
Nandps skip example:
https://github.com/Xilinx/embeddedsw/blob/master/XilinxProcessorIPLib/drivers/nandps/examples/xnandps_skip_example.cSame as nandps example. In addition to that it will verify the given block is bad or not. if it is bad block it skips that block and proceed with other good block.
Output:
Nand Flash Skip Block Method Example Test Successfully ran Nand Flash Skip Block Method Example Test |
Nandps cache example:
https://github.com/Xilinx/embeddedsw/blob/master/XilinxProcessorIPLib/drivers/nandps/examples/xnandps_cache_example.cSame as nandps example. In addition to that it will use the page cache read operations.
Output:
Nand Flash Read Write Example Test Successfully ran Nand Flash Read Write Example Test |
Performance
| Write(MBPS) | Read(MBPS) |
|---|---|
| 7.1 | 13.8 |