Claude review: soc: qcom: rpmh-rsc: Skip TCS init when RSC is managed by firmware

[Claude Code Review Bot <claude-review@example.com>]

Patch Review

**Concept**: When UEFI firmware leaves the RSC hardware solver active, skip TCS reinitialization to avoid a security violation.

**Issue 1 — Too much is skipped.** Looking at the normal probe path in `rpmh_rsc_probe()` (rpmh-rsc.c:1077-1131), the early return skips:
- `rpmh_probe_tcs_config()` (intended)
- Spinlock/waitqueue/bitmap initialization
- IRQ registration
- Active TCS interrupt enable
- Client cache list initialization
- **`devm_of_platform_populate()`** — child nodes (rpmh clients) will never probe

```c
+	if (readl_relaxed(drv->base + drv->regs[DRV_SOLVER_CONFIG]) &
+	    (DRV_HW_SOLVER_MASK << DRV_HW_SOLVER_SHIFT)) {
+		dev_dbg(&pdev->dev, "RSC already managed by firmware, skipping TCS init\n");
+		platform_set_drvdata(pdev, drv);
+		return 0;
+	}
```

The `drv` set as driver data has uninitialized `lock`, `tcs_wait`, `tcs_in_use`, `client.cache`, and `client.batch_cache`. If any consumer obtains this `drv` pointer and attempts an rpmh operation, it will operate on uninitialized data.

**Issue 2 — No `devm_of_platform_populate()`.** The commit message says "allowing other drivers to find the controller," but child platform devices of the RSC node won't be created without this call. Is the intent that the entire RSC subsystem should be inert on this platform? If so, the commit message should explain that. If children should still probe, then at minimum `devm_of_platform_populate()` needs to be called in the early-return path.

**Issue 3 — dev_dbg vs dev_info.** Silently skipping the entire RSC init path is a significant behavioral change. Using `dev_info` or `dev_notice` would help debug boot issues.

**Suggestion**: If the firmware-managed case truly means the kernel should not interact with this RSC at all, consider whether probing should succeed at all, or whether the driver should explicitly populate children while leaving TCS alone. The current approach creates a half-initialized driver data structure.

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Generated by Claude Code Patch Reviewer