.. _intel_ish:

Intel Integrated Sensor Hub (ISH) #################################

Overview

Intel Integrated Sensor Hub (ISH) is a lower-power/always-on co-processor inside many Intel Processors. It helps offload sensor processing tasks from the core processor for better power saving.

Hardware

LMT MinuteIA Core:
- 16KB instruction cache and 16KB data cache.
- 640KB SRAM space for code and data - implemented as L2 SRAM.
- 8KB AON RF space for code resident during deep D0i2/3 PG states.
Interface-to-Sensor peripherals (I2C, SPI, UART, I3C, GPIO, DMA).
Inter Process Communications (IPC) to core processor and other IP processors.

.. include:: ../../../../soc/intel/intel_ish/doc/supported_features.txt

Programming and Debugging

Use the following procedures for booting an ISH image on a ADL RVP board for Chrome.

.. contents:: :depth: 1 :local: :backlinks: top

Build Zephyr application

#. Build a Zephyr application; for instance, to build the hello_world application for ISH 5.4.1 on Intel ADL Processor:

.. zephyr-app-commands:: :zephyr-app: samples/hello_world :board: intel_ish_5_4_1 :goals: build

.. note::

  A Zephyr image file named :file:`ish_fw.bin` is automatically
  created in the build directory after the application is built.

Run ish_fw.bin on ADL RVP board for Chrome

Power on the ADL RVP board.
Log in Chrome OS. (Note: the user must have root access right, see Developer Mode_)
Re-mount the root filesystem as read-write:

.. code-block:: console

$ mount -o remount,rw /

If re-mount fails, execute below commands to Remove rootfs verification:

.. code-block:: console

$ /usr/share/vboot/bin/make_dev_ssd.sh --remove_rootfs_verification --partitions $ reboot

Go to the ISH firmware directory:

.. code-block:: console

$ cd /lib/firmware/intel

Relace the file adlrvp_ish.bin with zephyr image built out, ish_fw.bin.
Reboot, then observe Zephyr log output via ISH UART0.

.. _Developer Mode: https://chromium.googlesource.com/chromiumos/docs/+/HEAD/developer_mode.md