# Provide HLOS access to the SMMU

Configure instances that require HLOS access in the System Memory
Management Unit (SMMU) device tree.

## Provide HLOS access to the SMMU

1. Open the SMMU device tree file:

edk2-non-oss-qualcomm\Silicon\Qualcomm\Glymur\GlymurSiliconPkg\Settings\DeviceTree\Core\Buses\QupSMMU\QUPSMMU.dtsi
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2. Check whether the required instance is already defined.

    1. If the instance is already defined, update it as required.
    2. If the instance isn’t defined, create a new instance definition.
3. Assign the applicable macros to the instance.
4. Assign the required Generic Peripheral Interface (GPII) address.

    1. Confirm that the GPII isn’t assigned to another instance.
5. For a non-GSI use case, configure HLOS access.

    1. Set the VMID to HLOS.
    2. Set the node status to `okay`.

This configuration gives the serial engine SMMU access in HLOS.

se_vmid = <AC_VM_HLOS>; // Required in case of no active GPII use case
    config_status = "okay";
    ac_config{
        ac_config_0{ // AC config relevant to HLOS
            acvmid = <AC_VM_HLOS>; // Required for SMMU config (S2)
            gpii_region_addr = <QUPV3_0_GPII2_ADDR>; // QUP0 GPII2 address space dedicated to HLOS
            gpii_region_size = <QUPV3_GPII_REGION_SIZE>;
        };
        ac_config_1{
            acvmid = <AC_VM_HLOS>; // Required for SMMU config
            gpii_region_addr = <QUPV3_0_GPII3_ADDR>; // QUP0 GPII3 address space dedicated to HLOS
            gpii_region_size = <QUPV3_GPII_REGION_SIZE>;
        };
    };
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## Related

- [Enable the I2C interface](https://docs.qualcomm.com/doc/80-A0399-8/topic/enable-i2c-interface.html)
- [Enable the SPI interface](https://docs.qualcomm.com/doc/80-A0399-8/topic/enable-spi-interface.html)
- [Enable the UART interface](https://docs.qualcomm.com/doc/80-A0399-8/topic/enable-uart-interface.html)

Last Published: Sep 17, 2026

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