> ## Documentation Index
> Fetch the complete documentation index at: https://dragonwingdocs.qualcomm.com/llms.txt
> Use this file to discover all available pages before exploring further.

#  Bring-up and validation

Validate platform readiness and confirm that the MCU subsystem operates reliably across boot, interfaces, interrupts, and power transitions before scaling to full use cases. Focus on establishing a stable baseline, verifying key paths, and capturing debug evidence early. This helps you detect integration issues quickly, ensure consistent behavior under different conditions, and build confidence before enabling advanced features or optimizations.

**9.1 Bring-up checklist**

1. Load the default Qualcomm-supplied MCU image and verify execution from DDR.
2. Validate timer, serial-engine, GPIO wake, and attached peripheral interrupt routing.
3. Bring up one protocol at a time by using loopback or device.
4. Enable GPI or DMA only after the basic path is stable.
5. Exercise resource voting and confirm dependencies remain asserted for the full transfer
   duration.
6. Capture logs and fault data during boot, timeout, NACK or bus error, and low-power
   transitions.

**9.2 Apply initialization and configuration guidelines**

Prevent common sequencing mistakes during interface bring-up. <br />

**Prerequisites**<br />
■ The MCU boots reliably from DDR.<br />
**Procedure**

1. Bring up one protocol at a time, for example UART first, then I2C, then I3C if applicable.
2. Keep the initial payloads and trigger conditions small so you can isolate setup errors quickly.
3. Validate the simpler programmed-I/O or interrupt path before you enable GPI.
4. Confirm clocks, the CX rail, and any DDR dependency stay asserted for the full transfer
   duration.
5. Capture baseline logs and fault data during boot, timeout, NACK or bus error, and low-power
   transitions.

**Expected result.**

The interface comes up in a controlled order and each additional layer is added only after the simpler layer is stable.

**9.3 Minimum protocol and power validation**

Table 9-1 Minimum validation criteria

| Area         | Minimum validation                                                                                                                        |
| ------------ | ----------------------------------------------------------------------------------------------------------------------------------------- |
| UART         | Console input and output, receive overrun handling, and flow-control behavior if enabled.                                                 |
| I2C          | Read and write behavior, NACK handling, repeated-start behavior, timeout detection, and recovery                                          |
| I3C          | Addressing and configuration policy, transfer completion, and supported compatibility behavior.                                           |
| QUP plus GPI | Descriptor queueing, completion interrupts, ring drain and reset, timeout behavior, and abort handling.                                   |
| Power        | Known functional protocol path before entry, valid wake source, no data corruption on resume, and retained or restored state as expected. |

**9.4 Debug and fault capture**

Collect baseline boot logs before broad validation.

2. Collect logs again on timeout, transfer failure, bus error, and wake failure.

3. Store trace, register dumps, and fault data with the exact image and symbols.

4. Use a retained UART path or another stable debug transport as a constant reference across
   tests.