Patch "perf/arm-cmn: Fix DTC domain detection" 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

    perf/arm-cmn: Fix DTC domain detection

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:
     perf-arm-cmn-fix-dtc-domain-detection.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 fd5601211c170de8ae4aa49e1e4d272b6026ef65
Author: Robin Murphy <robin.murphy@xxxxxxx>
Date:   Fri Oct 20 18:51:25 2023 +0100

    perf/arm-cmn: Fix DTC domain detection
    
    [ Upstream commit e3e73f511c49c741f6309862c2248958ad77bbaa ]
    
    It transpires that dtm_unit_info is another register which got shuffled
    in CMN-700 without me noticing. Fix that in a way which also proactively
    fixes the fragile laziness of its consumer, just in case any further
    fields ever get added alongside dtc_domain.
    
    Fixes: 23760a014417 ("perf/arm-cmn: Add CMN-700 support")
    Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
    Reviewed-by: Ilkka Koskinen <ilkka@xxxxxxxxxxxxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/3076ee83d0554f6939fbb6ee49ab2bdb28d8c7ee.1697824215.git.robin.murphy@xxxxxxx
    Signed-off-by: Will Deacon <will@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
index 6b50bc5519846..caae2d3e9d3ea 100644
--- a/drivers/perf/arm-cmn.c
+++ b/drivers/perf/arm-cmn.c
@@ -112,7 +112,9 @@
 
 #define CMN_DTM_PMEVCNTSR		0x240
 
-#define CMN_DTM_UNIT_INFO		0x0910
+#define CMN650_DTM_UNIT_INFO		0x0910
+#define CMN_DTM_UNIT_INFO		0x0960
+#define CMN_DTM_UNIT_INFO_DTC_DOMAIN	GENMASK_ULL(1, 0)
 
 #define CMN_DTM_NUM_COUNTERS		4
 /* Want more local counters? Why not replicate the whole DTM! Ugh... */
@@ -2117,6 +2119,16 @@ static int arm_cmn_init_dtcs(struct arm_cmn *cmn)
 	return 0;
 }
 
+static unsigned int arm_cmn_dtc_domain(struct arm_cmn *cmn, void __iomem *xp_region)
+{
+	int offset = CMN_DTM_UNIT_INFO;
+
+	if (cmn->part == PART_CMN650 || cmn->part == PART_CI700)
+		offset = CMN650_DTM_UNIT_INFO;
+
+	return FIELD_GET(CMN_DTM_UNIT_INFO_DTC_DOMAIN, readl_relaxed(xp_region + offset));
+}
+
 static void arm_cmn_init_node_info(struct arm_cmn *cmn, u32 offset, struct arm_cmn_node *node)
 {
 	int level;
@@ -2248,7 +2260,7 @@ static int arm_cmn_discover(struct arm_cmn *cmn, unsigned int rgn_offset)
 		if (cmn->part == PART_CMN600)
 			xp->dtc = 0xf;
 		else
-			xp->dtc = 1 << readl_relaxed(xp_region + CMN_DTM_UNIT_INFO);
+			xp->dtc = 1 << arm_cmn_dtc_domain(cmn, xp_region);
 
 		xp->dtm = dtm - cmn->dtms;
 		arm_cmn_init_dtm(dtm++, xp, 0);