gpio
Xilinx Vitis Drivers API Documentation
gpio Documentation

This file contains the software API definition of the Xilinx General Purpose I/O (XGpio) device driver.The Xilinx GPIO controller is a soft IP core designed for Xilinx FPGAs and contains the following general features:

  • Support for up to 32 I/O discretes for each channel (64 bits total).
  • Each of the discretes can be configured for input or output.
  • Configurable support for dual channels and interrupt generation.

The driver provides interrupt management functions. Implementation of interrupt handlers is left to the user. Refer to the provided interrupt example in the examples directory for details.

This driver is intended to be RTOS and processor independent. Any needs for dynamic memory management, threads or thread mutual exclusion, virtual memory, or cache control must be satisfied by the layer above this driver.

Initialization & Configuration

The XGpio_Config structure is used by the driver to configure itself. This configuration structure is typically created by the tool-chain based on HW build properties.

To support multiple runtime loading and initialization strategies employed by various operating systems, the driver instance can be initialized in one of the following ways:

  • XGpio_Initialize(InstancePtr, DeviceId) - The driver looks up its own configuration structure created by the tool-chain based on an ID provided by the tool-chain.
  • XGpio_CfgInitialize(InstancePtr, CfgPtr, EffectiveAddr) - Uses a configuration structure provided by the caller. If running in a system with address translation, the provided virtual memory base address replaces the physical address present in the configuration structure.
Note

This API utilizes 32 bit I/O to the GPIO registers. With less than 32 bits, the unused bits from registers are read as zero and written as don't cares.

MODIFICATION HISTORY:
Ver   Who  Date     Changes


1.00a rmm 03/13/02 First release 2.00a jhl 11/26/03 Added support for dual channels and interrupts 2.01a jvb 12/14/05 I separated dependency on the static config table and xparameters.h from the driver initialization by moving _Initialize and _LookupConfig to _sinit.c. I also added the new _CfgInitialize routine. 2.11a mta 03/21/07 Updated to new coding style, added GetDataDirection 2.12a sv 11/21/07 Updated driver to support access through DCR bus 2.12a sv 06/05/08 Updated driver to fix the XGpio_InterruptDisable function to properly update the Interrupt Enable register 2.13a sdm 08/22/08 Removed support for static interrupt handlers from the MDD file 3.00a sv 11/21/09 Updated to use HAL Processor APIs. Renamed the macros XGpio_mWriteReg to XGpio_WriteReg and XGpio_mReadReg to XGpio_ReadReg. Removed the macros XGpio_mSetDataDirection, XGpio_mGetDataReg and XGpio_mSetDataReg. Users should use XGpio_WriteReg and XGpio_ReadReg to achieve the same functionality. 3.01a bss 04/18/13 Updated driver tcl to generate Canonical params in xparameters.h. CR#698589 4.0 adk 19/12/13 Updated as per the New Tcl API's 4.1 lks 11/18/15 Updated to use canonical xparameters in examples and clean up of the comments, removed support for DCR bridge and removed xgpio_intr_example for CR 900381 4.2 sk 08/16/16 Used UINTPTR instead of u32 for Baseaddress as part of adding 64 bit support. CR# 867425. Changed the prototype of XGpio_CfgInitialize API. 4.3 sk 09/29/16 Modified the example to make it work when LED_bits are configured as an output. CR# 958644 ms 01/23/17 Added xil_printf statement in main function for all examples to ensure that "Successfully ran" and "Failed" strings are available in all examples. This is a fix for CR-965028. ms 03/17/17 Added readme.txt file in examples folder for doxygen generation. 4.4 sne 04/25/19 Updated Makefile for IAR compier (CR-1029421). 4.5 sne 06/14/19 Fixed IAR compiler warnings on example files. 4.6 sne 08/11/19 Fixed compilation error of armcc compiler. 4.7 sne 08/28/20 Modify Makefile to support parallel make execution.