# `meta-qcom-realtime`

The `meta-qcom-realtime` metadata layer is available on
[GitHub](https://github.com/qualcomm-linux/meta-qcom-realtime). This layer provides
additional software support for building a real-time kernel for Qualcomm devices.

## Kernel recipes

Qualcomm Linux supports the LTS Qualcomm Linux kernel v6.6.x and real-time extensions.
It’s maintained through the `linux-qcom-custom-rt_6.6.bb` and `linux-qcom-base-rt_6.6.bb` Yocto recipes
at `recipes-kernel/linux` under the `meta-qcom-realtime` layer.
The pending pre-empt RT patches are found at [realtime](https://wiki.linuxfoundation.org/realtime/start).
These patches are fetched and applied on top of the `linux-qcom-custom-rt_6.6.bb`,
which is publicly hosted at [Codelinaro](https://git.codelinaro.org/clo/la/kernel/qcom.git).

To compile a real-time kernel for Qualcomm devices:

> 
> 
> - If you chose the `custom` OVERRIDE, `conf/layer.conf` selects `linux-qcom-custom-rt`.
> - If you chose the `base` OVERRIDE, `conf/layer.conf` selects `linux-qcom-base-rt`.

**Kernel configuration**

Both recipes append the `qcom_rt.cfg` fragment as follows:

KERNEL_CONFIG_FRAGMENTS:append = " ${WORKDIR}/qcom_rt.cfg"
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## Enable `meta-qcom-realtime` in build

To enable `meta-qcom-realtime` in the build, export the
`meta-qcom-realtime` layer to EXTRALAYERS in `bblayers.conf`, as
described in the following steps:

1. Source the environment.

    The following is an example to source the environment for a QCS6490-based machine and the `qcom-wayland` distribution:

MACHINE=qcs6490-rb3gen2-core-kit DISTRO=qcom-wayland source setup-environment
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2. Open the `build-qcom-wayland/conf/bblayers.conf` file and update
the EXTRALAYERS variable as follows:

EXTRALAYERS ?= " \
           ${WORKSPACE}/layers/meta-qcom-realtime \
           "
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3. Run the build command to rebuild with `meta-qcom-realtime` as
follows:

bitbake qcom-multimedia-image
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Last Published: Dec 21, 2025

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