Axi timer


Axi timer


Table of Contents

AXI Timer

Introduction


This page gives an overview of Axi Timer Linux driver which is available as part of the Linux distribution.The LogiCORE™ IP AXI Timer/Counter is a 32/ 64-bit timer module that interfaces to the AXI4-Lite interface.

HW IP features

  • AXI interface based on the AXI4-Lite specification
  • Two programmable interval timers with interrupt, event generation, and event capture capabilities
  • Configurable counter width
  • One Pulse Width Modulation (PWM) output
  • Cascaded operation of timers in generate and capture modes

Kernel Configuration

Existing driver ( https://github.com/Xilinx/linux-xlnx/blob/xlnx_rebase_v5.4_2020.1/arch/microblaze/kernel/timer.c)  is tightly coupled with Microblaze processor. By default it would be used as "arch timer" for Microblaze. 

Devicetree


Mainline status

Existing driver https://github.com/Xilinx/linux-xlnx/blob/master/arch/microblaze/kernel/timer.c is in sync with mainline.

Boot log snippet



Changelog



2017.4
  • None

2017.3
  • None

2017.4

  • None

2018.1

  • None

2018.2

  • None

2018.3

  • None

2019.1

Summary

microblaze: Remove architecture heart beat code

Commits

microblaze: Remove architecture heart beat code

2019.2

  • None

2020.1

Summary

Updated driver to support SMP Microblaze systems

Commits

microblaze: timer: Make timer SMP aware

microblaze: timer: Change timer initialization setting

microblaze: timer: Detect cpu_id from DT

microblaze: timer: Group clockevent setting together

microblaze: timer: Make sure that clockevent timer is initialized properly

microblaze: timer: Create per cpu clockevent device

microblaze: timer: Covert timer to use cpu hotplug

2020.2

  • None