Re: [PATCH net-next v14 2/4] net: pse-pd: add Realtek PSE MCU core

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] rtpse_mcu_resp_is_final() excludes RTPSE_MCU_OPCODE_NOT_READY, which breaks the bounded retry mechanism.
--

--- Patch [2]: [PATCH net-next v14 2/4] net: pse-pd: add Realtek PSE MCU core ---
commit 4ec3b6f7573cbef331580bfd04e92ce4ccdb71d2
Author: Jonas Jelonek <[email protected]>

net: pse-pd: add Realtek PSE MCU core

This commit introduces the core driver module for the microcontroller 
fronting PSE silicon on Realtek-based PoE switches. It implements the 
message-based protocol, parsing for Gen1 and Gen2 dialects, and exposes 
a registration interface for transport drivers.

> --- /dev/null
> +++ b/drivers/net/pse-pd/realtek-pse-mcu.h
> @@ -0,0 +1,94 @@

[ ... ]

> +/*
> + * A polling transport can stop here: the reply to this request (opcode and
> + * seq_num) or a terminal error. The seq_num rejects a stale normal reply; the
> + * terminal errors match unconditionally, as a request the MCU couldn't parse
> + * carries no seq_num to correlate against.
> + */
> +static inline bool rtpse_mcu_resp_is_final(const struct rtpse_mcu_msg *req,
> +					   const struct rtpse_mcu_msg *resp)
> +{
> +	return (resp->opcode == req->opcode && resp->seq_num == req->seq_num) ||
> +	       resp->opcode == RTPSE_MCU_OPCODE_INCOMPLETE ||
> +	       resp->opcode == RTPSE_MCU_OPCODE_BAD_CSUM;
> +}

[Severity: Medium]
Does rtpse_mcu_resp_is_final() need to include RTPSE_MCU_OPCODE_NOT_READY?

If a polling transport relies on this helper to wait for the MCU response, it
will ignore NOT_READY messages and continue polling until it times out. 

This would prevent the core driver from handling the transient busy state, as
the transport would return a timeout error instead of passing the NOT_READY
reply back to rtpse_mcu_do_xfer() for its bounded retry loop:

drivers/net/pse-pd/realtek-pse-mcu-core.c:rtpse_mcu_do_xfer() {
    ...
			ret = pse->transport->recv(pse, req, resp);
			if (ret)
				return ret;
    ...
		/* NOT_READY: MCU busy, wants the command resent; bounded retry. */
		if (resp->opcode != RTPSE_MCU_OPCODE_NOT_READY ||
		    tries >= RTPSE_MCU_NOT_READY_RETRIES)
			break;
		msleep(RTPSE_MCU_RESPONSE_MS);
    ...
}

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=2