AMI Architecture

Overview

The AMR Management Interface (AMI) provides host-access to control
and manage the Advanced Management Controller (AMC).

It consists of:

• A kernel driver, providing access to the AMR platform via the sGCQ (Simplified Generic Command Queue) interface.

• An API (libami), providing a user-space abstraction to the kernel driver.

• A command line tool (amitool), providing a human-readable interface to the API.

Note: The AMI is an example design demonstrating how an AMR host interface might be developed. It is not intended to be the final implementation for AMR runtime management and control.

Key Components

Kernel Driver

• Communicates with AMC firmware via sGCQ

• Manages PCIe configuration space and VSEC capabilities

• Provides character device interface for user-space access

• Implements sensor monitoring via Linux hwmon framework

• Handles AMC heartbeat monitoring and logging

API Library (libami)

• C library providing programmatic access to AMC functionality

• Abstracts kernel driver interactions

• Supports:

  • Device discovery and management

  • Sensor data collection

  • Manufacturing information access

  • Memory-mapped I/O operations

  • EEPROM and QSFP module access

  • PDI download and partition management

Command Line Tool (amitool)

• User-friendly interface to libami API

• Supports interactive and scripted operations

• Provides commands for diagnostics, monitoring, and management

Communication Architecture

Request/Response Flow

The AMI uses a synchronous request/response model:

1. User Space → API calls libami functions

2. libami → Issues ioctl() to kernel driver

3. Kernel Driver → Submits request via AMC Proxy

4. AMC Proxy → Sends request through sGCQ to AMC firmware

5. Kernel Driver → Blocks on completion variable

6. AMC Firmware → Processes request and sends response via sGCQ

7. AMC Proxy → Invokes callback (amc_proxy_callback)

8. Kernel Driver → Signals completion variable and unblocks

9. libami → Returns data to user application

Timeouts

• Most commands: 150 seconds

• Partition copy: 60 minutes

• Heartbeat: 0.5 seconds

Top Level Block Diagram

Behavior

Initialisation

Card Detection, Selection, and General
Overview

Command Line Tool

AMR Management Interface User Guide
(amitool)

API Abstraction

AMI - API Description

Driver Interaction

AMI - Kernel Driver Interaction

Sensor Control

Sensors and Hardware Monitoring

Device Reboot

AMI - Device Reboot

Version Compatibility

The AMI driver checks for compatible AMC firmware versions during
initialization. When version mismatch is detected, the driver
operates in compatibility mode with reduced functionality. For full feature support, ensure AMC firmware version matches the AMI driver version.