1\ingroup GroupModules Modules
2\defgroup GroupMHU3 MHU Hardware version 3 driver.
3
4# MHU Hardware version 3 driver
5
6
7Copyright (c) 2022, Arm Limited and Contributors. All rights reserved.
8
9## Overview
10
11This is a driver module that supports MHU hardware version 3.
12
13Although, MHUv3 specifications specify various extensions, at the moment, only
14the following extensions are supported by this driver:
15
161. Doorbell Channel extension
172. Fast Channel extension
18
19### Limitations
20
21Doorbell channel implementation is limited to 32 doorbell channels for
22efficiency reasons.
23
24However, this can be extended to support more on a larger system with more
25powerful processors. In general, although MHUv3 specification allows up to 128
26channels, on a practical system for a SCP use case, the number of doorbell
27channels is expected to remain < 32.
28