boards: nxp: imxrt700: Add documentation for i.MXRT700 DSP cores

Overview

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The new i.MX RT700 CPU architecture is composed of a high-performance main compute subsystem,

The new i.MX RT700 CPU architecture is composed of a high-performance main-compute subsystem,

a secondary “always-on” sense-compute subsystem and specialized coprocessors.

The main compute subsystem uses a 325 MHz capable Arm® Cortex®-M33 (CM33).

Similar to the i.MX RT600 crossover MCU, the i.MX RT700 includes a Cadence Tensilica® HiFi 4 DSP.

The main-compute subsystem has a primary Arm® Cortex®-M33 running at 325 MHz, with an integrated

Cadence® Tensilica® HiFi 4 DSP for more demanding DSP and audio processing tasks.

The sense-compute subsystem has a second Arm® Cortex®-M33 and an integrated Cadence® Tensilica®

HiFi 1 DSP. This removes the need for an external sensor hub, reducing system design complexity,

footprint and BOM costs.

The HiFi4 is a high performance DSP core based upon a Very Long Instruction Word (VLIW) architecture,

which is capable of processing up to eight 32x16 MACs per instruction cycle. It can be used for offloading

high-performance numerical tasks such as audio and image processing and supports both fixed-point and

floating-point operations.

The i.MX RT700 also features NXP’s eIQ Neutron NPU, enabled with the eIQ machine learning software

development environment.

Hardware

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- Main Compute Subsystem:

   - Arm Cortex-M33 up to 325 MHz

   - HiFi 4 DSP up to 325 MHz

   - eIQ Neutron NPU up to 325 MHz

- Sense Compute Subsystem:

   - Arm Cortex-M33 up to 250 MHz

   - HiFi 1 DSP up to 250 MHz

- 7.5 MB on-chip SRAM

The MIMXRT700 EVK is configured to use the Systick

as a source for the system clock.

HiFi1 DSP Core

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One can build a Zephyr application for the i.MX RT700 HiFi 1  DSP core by targeting the HiFi 1

SOC. Xtensa toolchain supporting RT700 DSP cores is included in Zephyr SDK.

To build the hello_world sample for the i.MX RT700 HiFi 1 DSP core:

.. zephyr-app-commands::

   :tool: west

   :zephyr-app: samples/hello_world

   :board: mimxrt700_evk/mimxrt798s/hifi1

   :goals: build

HiFi4 DSP Core

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One can build a Zephyr application for the i.MX RT700 HiFi 4  DSP core by targeting the HiFi 4

SOC. Xtensa toolchain supporting RT700 DSP cores is included in Zephyr SDK.

To build the hello_world sample for the i.MX RT700 HiFi 4 DSP core:

.. zephyr-app-commands::

   :tool: west

   :zephyr-app: samples/hello_world

   :board: mimxrt700_evk/mimxrt798s/hifi4

   :goals: build

Programming and Debugging

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