Commit 5d8a7662 authored by Cristian Marussi's avatar Cristian Marussi Committed by Ulf Hansson
Browse files

firmware: arm_scmi: Skip opp duplicates 



Buggy firmware can reply with duplicated PERF opps descriptors.

Ensure that the bad duplicates reported by the platform firmware doesn't
get added to the opp-tables.

Reported-by: default avatarJohan Hovold <johan+linaro@kernel.org>
Closes: https://lore.kernel.org/lkml/ZoQjAWse2YxwyRJv@hovoldconsulting.com/


Signed-off-by: default avatarCristian Marussi <cristian.marussi@arm.com>
Tested-by: default avatarJohan Hovold <johan+linaro@kernel.org>
Reviewed-by: default avatarSudeep Holla <sudeep.holla@arm.com>
Cc: stable@vger.kernel.org
Message-ID: <20241030125512.2884761-3-quic_sibis@quicinc.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent f7c7c5aa

drivers/firmware/arm_scmi/perf.c

+30 −10
Original line number Diff line number Diff line
@@ -373,7 +373,7 @@ static int iter_perf_levels_update_state(struct scmi_iterator_state *st, 
	return 0;

}



static inline void

static inline int

process_response_opp(struct device *dev, struct perf_dom_info *dom,

		     struct scmi_opp *opp, unsigned int loop_idx,

		     const struct scmi_msg_resp_perf_describe_levels *r)
@@ -386,12 +386,16 @@ process_response_opp(struct device *dev, struct perf_dom_info *dom, 
		le16_to_cpu(r->opp[loop_idx].transition_latency_us);



	ret = xa_insert(&dom->opps_by_lvl, opp->perf, opp, GFP_KERNEL);

	if (ret)

	if (ret) {

		dev_warn(dev, "Failed to add opps_by_lvl at %d for %s - ret:%d\n",

			 opp->perf, dom->info.name, ret);

		return ret;

	}



	return 0;

}



static inline void

static inline int

process_response_opp_v4(struct device *dev, struct perf_dom_info *dom,

			struct scmi_opp *opp, unsigned int loop_idx,

			const struct scmi_msg_resp_perf_describe_levels_v4 *r)
@@ -404,9 +408,11 @@ process_response_opp_v4(struct device *dev, struct perf_dom_info *dom, 
		le16_to_cpu(r->opp[loop_idx].transition_latency_us);



	ret = xa_insert(&dom->opps_by_lvl, opp->perf, opp, GFP_KERNEL);

	if (ret)

	if (ret) {

		dev_warn(dev, "Failed to add opps_by_lvl at %d for %s - ret:%d\n",

			 opp->perf, dom->info.name, ret);

		return ret;

	}



	/* Note that PERF v4 reports always five 32-bit words */

	opp->indicative_freq = le32_to_cpu(r->opp[loop_idx].indicative_freq);
@@ -415,13 +421,21 @@ process_response_opp_v4(struct device *dev, struct perf_dom_info *dom, 


		ret = xa_insert(&dom->opps_by_idx, opp->level_index, opp,

				GFP_KERNEL);

		if (ret)

		if (ret) {

			dev_warn(dev,

				 "Failed to add opps_by_idx at %d for %s - ret:%d\n",

				 opp->level_index, dom->info.name, ret);



			/* Cleanup by_lvl too */

			xa_erase(&dom->opps_by_lvl, opp->perf);



			return ret;

		}



		hash_add(dom->opps_by_freq, &opp->hash, opp->indicative_freq);

	}



	return 0;

}



static int
@@ -429,16 +443,22 @@ iter_perf_levels_process_response(const struct scmi_protocol_handle *ph, 
				  const void *response,

				  struct scmi_iterator_state *st, void *priv)

{

	int ret;

	struct scmi_opp *opp;

	struct scmi_perf_ipriv *p = priv;



	opp = &p->perf_dom->opp[st->desc_index + st->loop_idx];

	opp = &p->perf_dom->opp[p->perf_dom->opp_count];

	if (PROTOCOL_REV_MAJOR(p->version) <= 0x3)

		process_response_opp(ph->dev, p->perf_dom, opp, st->loop_idx,

				     response);

		ret = process_response_opp(ph->dev, p->perf_dom, opp,

					   st->loop_idx, response);

	else

		process_response_opp_v4(ph->dev, p->perf_dom, opp, st->loop_idx,

					response);

		ret = process_response_opp_v4(ph->dev, p->perf_dom, opp,

					      st->loop_idx, response);



	/* Skip BAD duplicates received from firmware */

	if (ret)

		return ret == -EBUSY ? 0 : ret;



	p->perf_dom->opp_count++;



	dev_dbg(ph->dev, "Level %d Power %d Latency %dus Ifreq %d Index %d\n",