drivers: pcie: single vector allocation is failing with pcie_msi_vectors_allocate() #93319
Description
Describe the bug
PCIe endpoint devices with MSI-X support typically use the pcie_msi_vectors_allocate() API call to allocate MSI-X interrupt vectors. The function operates correctly when allocating multiple vectors (n_vector > 1), however, it fails to allocate successfully when only a single vector is requested (n_vector = 1). Also,
The pcie_msi_vectors_allocate() API returns uint8_t, but the driver implementation returns -1 in some code paths, creating a type mismatch.
Regression
- This is a regression.
Steps to reproduce
No response
Relevant log output
Impact
Functional Limitation – Some features not working as expected, but system usable.
Environment
No response
Additional Context
During this experiment, CONFIG_INTEL_VTD_ICTL is disabled.