Axi timer

AXI Timer

Introduction

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

        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

/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

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

• http://www.xilinx.com/support/documentation/ip_documentation/axi_timer/v2_0/pg079-axi-timer.pdf

Changelog

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