[PATCH v2 net-next 6/8] net: ena: Update PHC admin interface for error bound support

[Arthur Kiyanovski <akiyano@amazon.com>]

Extend the ENA admin interface to support error bound.

Add error_bound to the PHC response structure.
Introduce a feature version mechanism to indicate device supports
error_bound, and add an error flag for error_bound retrieval failures.

This enables the driver to retrieve error_bound information from the
device alongside timestamps.

Signed-off-by: Amit Bernstein <amitbern@amazon.com>
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
---
 .../net/ethernet/amazon/ena/ena_admin_defs.h    | 17 +++++++++++------
 drivers/net/ethernet/amazon/ena/ena_com.c       | 11 ++++++-----
 2 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_admin_defs.h b/drivers/net/ethernet/amazon/ena/ena_admin_defs.h
index 898ecd9..2d132c4 100644
--- a/drivers/net/ethernet/amazon/ena/ena_admin_defs.h
+++ b/drivers/net/ethernet/amazon/ena/ena_admin_defs.h
@@ -128,12 +128,14 @@ enum ena_admin_get_stats_scope {
 	ENA_ADMIN_ETH_TRAFFIC                       = 1,
 };
 
-enum ena_admin_phc_type {
-	ENA_ADMIN_PHC_TYPE_READLESS                 = 0,
+enum ena_admin_phc_feature_version {
+	/* Readless with error_bound */
+	ENA_ADMIN_PHC_FEATURE_VERSION_0             = 0,
 };
 
 enum ena_admin_phc_error_flags {
 	ENA_ADMIN_PHC_ERROR_FLAG_TIMESTAMP   = BIT(0),
+	ENA_ADMIN_PHC_ERROR_FLAG_ERROR_BOUND = BIT(1),
 };
 
 /* ENA SRD configuration for ENI */
@@ -1035,10 +1037,10 @@ struct ena_admin_queue_ext_feature_desc {
 };
 
 struct ena_admin_feature_phc_desc {
-	/* PHC type as defined in enum ena_admin_get_phc_type,
-	 * used only for GET command.
+	/* PHC version as defined in enum ena_admin_phc_feature_version,
+	 * used only for GET command as max supported PHC version by the device.
 	 */
-	u8 type;
+	u8 version;
 
 	/* Reserved - MBZ */
 	u8 reserved1[3];
@@ -1224,7 +1226,10 @@ struct ena_admin_phc_resp {
 	/* PHC timestamp (nsec) */
 	u64 timestamp;
 
-	u8 reserved2[12];
+	u8 reserved2[8];
+
+	/* Timestamp error limit (nsec) */
+	u32 error_bound;
 
 	/* Bit field of enum ena_admin_phc_error_flags */
 	u32 error_flags;
diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
index e67b592..1549d6e 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -1682,11 +1682,11 @@ int ena_com_phc_config(struct ena_com_dev *ena_dev)
 	struct ena_admin_set_feat_cmd set_feat_cmd;
 	int ret = 0;
 
-	/* Get device PHC default configuration */
+	/* Get default device PHC configuration */
 	ret = ena_com_get_feature(ena_dev,
 				  &get_feat_resp,
 				  ENA_ADMIN_PHC_CONFIG,
-				  0);
+				  ENA_ADMIN_PHC_FEATURE_VERSION_0);
 	if (unlikely(ret)) {
 		netdev_err(ena_dev->net_device,
 			   "Failed to get PHC feature configuration, error: %d\n",
@@ -1694,10 +1694,11 @@ int ena_com_phc_config(struct ena_com_dev *ena_dev)
 		return ret;
 	}
 
-	/* Supporting only readless PHC retrieval */
-	if (get_feat_resp.u.phc.type != ENA_ADMIN_PHC_TYPE_READLESS) {
+	/* Supporting only PHC V0 (readless mode with error bound) */
+	if (get_feat_resp.u.phc.version != ENA_ADMIN_PHC_FEATURE_VERSION_0) {
 		netdev_err(ena_dev->net_device,
-			   "Unsupported PHC type, error: %d\n",
+			   "Unsupported PHC version (0x%X), error: %d\n",
+			   get_feat_resp.u.phc.version,
 			   -EOPNOTSUPP);
 		return -EOPNOTSUPP;
 	}
-- 
2.47.3