Table of Contents

Introduction

This page gives an overview of sdps 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/sdps/


Driver source code is organized into different folders. Below diagram shows the sdps driver source organization

sdps
|
-- Doc - Provides the API and data structure details
|
- Source - Driver source files

Features Supported by HW/SW

• 1 or 4 bit bus width
• Normal or High speed (and configurable clock)
• ADMA2 transfers
• Polled mode
• Switch command
• All ACMD’s and CMD’s involved in initialization and transfer states
• Configurable block size
• Block and direct addressable
• Error detection

Features Not Supported

• SDMA mode
• Programmed IO mode
• Interrupts
• Lock/Unlock/Write protection

Known issues and Limitations

Driver supports only polled mode.

Test cases

The file system example is xilffs_polled_example.c
This file system example creates a new file in an SD/eMMC card (formatted with file system) writes a sequence into the files and reads it back to verify. This example can be modified to write user data to a file or read existing files as required. The API’s are standard file system API’s.

code

code

Changelog

2016.3

• Added support for mkfs in the sd driver. It will calculate the sector size and number of sectors to identify the card capacity.
• Used usleep API across all the platforms, since MB_SLEEP API is deprecated.
• Added bus_width, mio_bank and has_emio parameters to tcl file to export to xparameters.h
• Added support for UHS mode switching based on the card capability.
• Added Tap delays inside the drivers required for High Speed modes and UHS modes.

2016.4

• Reduce the delay during power cycle from one second to one milli second.
• Used emmc_hwreset pin to reset eMMC card rather than relying on power cycle.
• Enable Rst_n bit in EXT_CSD reg if disabled - This is to enable hw reset functionality in eMMC device.
• Implemented revived auto-tuning workaround by implementing dll_reset during tuning process.

AR# 68109 - for SD boot time increase in 2016.3

2017.1

• None

2017.2

• None

2017.3

• Added support for word access system
• Resolved compilation issues with ARMCC and ICCARM compilers

2018.1

• None

2018.2

• None

2018.3

• None

2019.1

• None

2019.2

• Added cache invalidation after getting bus width information as ARM suggested.

2020.1

• None

2020.2

• None