Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.


Axi timer


Table of Contents

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

Code Block
themeMidnight
        axi_timer_1: timer@41c00000 {
            clock-frequency = <100000000>;
            clocks = <&clk_bus_0>;
            compatible = "xlnx,xps-timer-1.00.a";
            interrupt-parent = <&axi_intc_1>;
            interrupts = <2 2>;
            reg = <0x41c00000 0x10000>;
            xlnx,count-width = <0x20>;
            xlnx,one-timer-only = <0x0>;
        };

Mainline status

Existing driver https://github.com/Xilinx/linux-xlnx/blob/master/arch/microblaze/kernel/timer.c is in sync with mainline, except changes related to SMP support.

Boot log snippet

Code Block
themeMidnight
/amba_pl/timer@41c00000: irq=2
xilinx_timer_set_mode: shutdown
xilinx_timer_set_mode: periodic
sched_clock: 32 bits at 100MHz, resolution 10ns, wraps every 42949672950ns


Code Block
themeMidnight
<span style="font-family: arial,helvetica,sans-serif; font-size: 1.4em; line-height: 1.5;">**Related Links**


Changelog

2024.2

  • None

2024.1

  • None

2023.2

  • None

2023.1

  • None

2022.2

  • None

2022.1

  • None

2021.2

  • Addressed warnings reported by coverity tool

2021.1

  • None

2020.2

  • None

2020.1

  • Updated driver to support SMP Microblaze systems

2019.2

  • None

2019.1

  • microblaze: Remove architecture heart beat code