### What this PR does / why we need it?
Issue: If a model such as Ling-1T adopts partial rotary position
embedding (partial RoPE), but config.json uses the rotary_dim parameter
instead of partial_rotary_factor, it will trigger a RuntimeError: The
expanded size of the tensor (128) must match the existing size (64) at
non-singleton dimension 3.
<img width="1681" height="472" alt="image"
src="https://github.com/user-attachments/assets/ba03d7df-ecba-4d6f-9ec1-4dc55f59799e"
/>
This PR addresses an issue where models using partial rotary position
embedding (partial RoPE) with the `rotary_dim` parameter in
`config.json` (instead of `partial_rotary_factor`) would encounter a
`RuntimeError`.
This change adds support for the `rotary_dim` parameter in
`vllm_ascend/ops/rotary_embedding.py` to correctly calculate the
`rope_dim`, resolving the tensor size mismatch error.
### Does this PR introduce _any_ user-facing change?
No.
### How was this patch tested?
The patch was tested successfully with the Ling-1T model, which
previously triggered the error.
- vLLM version: v0.15.0
- vLLM main:
d7e17aaacd
Signed-off-by: GoCHug <93277779+GoCHug@users.noreply.github.com>
80e5812b39