Drivers: MPSL: Reduce flash radio sync timeout for Mesh use cases

[ludvigsj]

After changes in how MPSL uses the
CONFIG_SOC_FLASH_NRF_RADIO_SYNC_MPSL_NORMAL_PRIORITY_TIMEOUT_US value, Mesh applications started observing some slowdown in roundtrip point-to-point message and response. This is because Mesh now needs to wait for the entire timeout as part of a roundtrip. Decreasing the timeout to 5ms moves us close to where we were before the recent changes to MPSL, without over-prioritizing flash timeslots.

[Copilot]

Pull Request Overview

This PR addresses a performance regression in Bluetooth Mesh applications caused by recent changes in MPSL's usage of the radio sync timeout configuration. The PR reduces the default timeout from 10ms to 5ms specifically for Mesh use cases to restore acceptable roundtrip message timing without compromising flash operation priority.

Key Changes:

• Reduced flash radio sync timeout to 5ms for BT_MESH configurations to improve roundtrip message latency

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[NordicBuilder]

CI Information

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Build number: 4

Inputs:

Sources:

sdk-nrf: PR head: a8994f064b5e03bf7f7f8fcb5ac1d47377d65d48

more details

sdk-nrf:

PR head: a8994f064b5e03bf7f7f8fcb5ac1d47377d65d48
merge base: b708336d5f3b9cc9ba91176e97d975c4295e01ba
target head (main): 6d2fcf8cbbc73fc0a2c8ef585538b8e3bba1115f
Diff

Github labels

Enabled	Name	Description
	ci-disabled	Disable the ci execution
	ci-all-test	Run all of ci, no test spec filtering will be done
	ci-force-downstream	Force execution of downstream even if twister fails
	ci-run-twister	Force run twister
	ci-run-zephyr-twister	Force run zephyr twister

List of changed files detected by CI (1)

drivers
│  ├── mpsl
│  │  ├── flash_sync
│  │  │  │ Kconfig

Outputs:

Toolchain

Version: df3cc9d822
Build docker image: docker-dtr.nordicsemi.no/sw-production/ncs-build:df3cc9d822_e595b21c39

Test Spec & Results: ✅ Success; ❌ Failure; 🟠 Queued; 🟡 Progress; ◻️ Skipped; ⚠️ Quarantine

• ◻️ Toolchain - Skipped: existing toolchain is used
• ✅ Build twister - Skipped: Skipping Build & Test as it succeeded in a previous run: 3
• ✅ Integration tests
  • ✅ test_ble_nrf_config - Skipped: Job was skipped as it succeeded in a previous run
  • ✅ test-fw-nrfconnect-ble_samples - Skipped: Job was skipped as it succeeded in a previous run
  • ✅ test-fw-nrfconnect-chip - Skipped: Job was skipped as it succeeded in a previous run
  • ✅ test-fw-nrfconnect-rs
  • ✅ test-fw-nrfconnect-fem - Skipped: Job was skipped as it succeeded in a previous run
  • ✅ test-fw-nrfconnect-thread-main - Skipped: Job was skipped as it succeeded in a previous run
  • ✅ test-sdk-find-my - Skipped: Job was skipped as it succeeded in a previous run

Disabled integration tests

• • test-fw-nrfconnect-nrf_lrcs_positioning
  • desktop52_verification
  • test-fw-nrfconnect-apps
  • test-fw-nrfconnect-ble_mesh
  • test-fw-nrfconnect-nfc
  • test-fw-nrfconnect-nrf-iot_libmodem-nrf
  • test-fw-nrfconnect-nrf-iot_lwm2m
  • test-fw-nrfconnect-nrf-iot_samples
  • test-fw-nrfconnect-nrf-iot_thingy91
  • test-fw-nrfconnect-nrf-iot_zephyr_lwm2m
  • test-fw-nrfconnect-nrf_crypto
  • test-fw-nrfconnect-ps-main
  • test-fw-nrfconnect-rpc
  • test-fw-nrfconnect-tfm
  • test-low-level
  • test-sdk-audio
  • test-sdk-dfu
  • test-sdk-mcuboot
  • test-sdk-wifi
  • test-secdom-samples-public

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

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[ludvigsj]

@nrfconnect/ncs-co-drivers could you please take a look at this now? We need to get this in for NCS 3.2.0

[jfischer-no]

LGTM