Patch "firmware: arm_scmi: Fix possible frequency truncation when using level indexing mode" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    firmware: arm_scmi: Fix possible frequency truncation when using level indexing mode

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     firmware-arm_scmi-fix-possible-frequency-truncation-.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit a6b7e024eaf5605dcdfa2801a8c2901fc81fc64a
Author: Sudeep Holla <sudeep.holla@xxxxxxx>
Date:   Thu Nov 30 20:43:43 2023 +0000

    firmware: arm_scmi: Fix possible frequency truncation when using level indexing mode
    
    [ Upstream commit 77f5032e94f244ba08db51e17ca8f37bd7ff9acb ]
    
    The multiplier is already promoted to unsigned long, however the
    frequency calculations done when using level indexing mode doesn't
    use the multiplier computed. It instead hardcodes the multiplier
    value of 1000 at all the usage sites.
    
    Clean that up by assigning the multiplier value of 1000 when using
    the perf level indexing mode and update the frequency calculations to
    use the multiplier instead. It should fix the possible frequency
    truncation for all the values greater than or equal to 4GHz on 64-bit
    machines.
    
    Fixes: 31c7c1397a33 ("firmware: arm_scmi: Add v3.2 perf level indexing mode support")
    Reported-by: Sibi Sankar <quic_sibis@xxxxxxxxxxx>
    Closes: https://lore.kernel.org/all/20231129065748.19871-3-quic_sibis@xxxxxxxxxxx/
    Cc: Cristian Marussi <cristian.marussi@xxxxxxx>
    Link: https://lore.kernel.org/r/20231130204343.503076-2-sudeep.holla@xxxxxxx
    Reviewed-by: Cristian Marussi <cristian.marussi@xxxxxxx>
    Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
index 596316e6e1ba3..e887fd1690434 100644
--- a/drivers/firmware/arm_scmi/perf.c
+++ b/drivers/firmware/arm_scmi/perf.c
@@ -268,7 +268,8 @@ scmi_perf_domain_attributes_get(const struct scmi_protocol_handle *ph,
 		dom_info->sustained_perf_level =
 					le32_to_cpu(attr->sustained_perf_level);
 		if (!dom_info->sustained_freq_khz ||
-		    !dom_info->sustained_perf_level)
+		    !dom_info->sustained_perf_level ||
+		    dom_info->level_indexing_mode)
 			/* CPUFreq converts to kHz, hence default 1000 */
 			dom_info->mult_factor =	1000;
 		else
@@ -813,7 +814,7 @@ static int scmi_dvfs_device_opps_add(const struct scmi_protocol_handle *ph,
 		if (!dom->level_indexing_mode)
 			freq = dom->opp[idx].perf * dom->mult_factor;
 		else
-			freq = dom->opp[idx].indicative_freq * 1000;
+			freq = dom->opp[idx].indicative_freq * dom->mult_factor;
 
 		ret = dev_pm_opp_add(dev, freq, 0);
 		if (ret) {
@@ -862,7 +863,8 @@ static int scmi_dvfs_freq_set(const struct scmi_protocol_handle *ph, u32 domain,
 	} else {
 		struct scmi_opp *opp;
 
-		opp = LOOKUP_BY_FREQ(dom->opps_by_freq, freq / 1000);
+		opp = LOOKUP_BY_FREQ(dom->opps_by_freq,
+				     freq / dom->mult_factor);
 		if (!opp)
 			return -EIO;
 
@@ -896,7 +898,7 @@ static int scmi_dvfs_freq_get(const struct scmi_protocol_handle *ph, u32 domain,
 		if (!opp)
 			return -EIO;
 
-		*freq = opp->indicative_freq * 1000;
+		*freq = opp->indicative_freq * dom->mult_factor;
 	}
 
 	return ret;
@@ -919,7 +921,7 @@ static int scmi_dvfs_est_power_get(const struct scmi_protocol_handle *ph,
 		if (!dom->level_indexing_mode)
 			opp_freq = opp->perf * dom->mult_factor;
 		else
-			opp_freq = opp->indicative_freq * 1000;
+			opp_freq = opp->indicative_freq * dom->mult_factor;
 
 		if (opp_freq < *freq)
 			continue;