[PATCH] platform/x86/intel-uncore-freq: Handle autonomous UFS status bit

[PATCH] platform/x86/intel-uncore-freq: Handle autonomous UFS status bit

[Srinivas Pandruvada]

When the AUTONOMOUS_UFS_DISABLED bit is set in the header, the ELC
(Efficiency Latency Control) feature is non-functional. Hence, return
error for read or write to ELC attributes.

Fixes: bb516dc79c4a ("platform/x86/intel-uncore-freq: Add support for efficiency latency control")
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: stable@vger.kernel.org
---
Not urgent: In any current generations, it is never the case.

 .../x86/intel/uncore-frequency/uncore-frequency-tpmi.c     | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c
index 1237d9570886..b038dbb69447 100644
--- a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c
+++ b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c
@@ -537,6 +537,7 @@ static void set_cdie_id(int domain_id, struct tpmi_uncore_cluster_info *cluster_
 #define UNCORE_VERSION_MASK			GENMASK_ULL(7, 0)
 #define UNCORE_LOCAL_FABRIC_CLUSTER_ID_MASK	GENMASK_ULL(15, 8)
 #define UNCORE_CLUSTER_OFF_MASK			GENMASK_ULL(7, 0)
+#define UNCORE_AUTONOMOUS_UFS_DISABLED		BIT(32)
 #define UNCORE_MAX_CLUSTER_PER_DOMAIN		8
 
 static int uncore_probe(struct auxiliary_device *auxdev, const struct auxiliary_device_id *id)
@@ -598,6 +599,7 @@ static int uncore_probe(struct auxiliary_device *auxdev, const struct auxiliary_
 
 	for (i = 0; i < num_resources; ++i) {
 		struct tpmi_uncore_power_domain_info *pd_info;
+		bool auto_ufs_enabled;
 		struct resource *res;
 		u64 cluster_offset;
 		u8 cluster_mask;
@@ -647,6 +649,8 @@ static int uncore_probe(struct auxiliary_device *auxdev, const struct auxiliary_
 			continue;
 		}
 
+		auto_ufs_enabled = !(header & UNCORE_AUTONOMOUS_UFS_DISABLED);
+
 		/* Find out number of clusters in this resource */
 		pd_info->cluster_count = hweight8(cluster_mask);
 
@@ -689,7 +693,8 @@ static int uncore_probe(struct auxiliary_device *auxdev, const struct auxiliary_
 
 			cluster_info->uncore_root = tpmi_uncore;
 
-			if (TPMI_MINOR_VERSION(pd_info->ufs_header_ver) >= UNCORE_ELC_SUPPORTED_VERSION)
+			if (TPMI_MINOR_VERSION(pd_info->ufs_header_ver) >=
+			    UNCORE_ELC_SUPPORTED_VERSION && auto_ufs_enabled)
 				cluster_info->elc_supported = true;
 
 			ret = uncore_freq_add_entry(&cluster_info->uncore_data, 0);
-- 
2.52.0