RDMA/efa: Report link speed according to device attributes

JIRA: https://issues.redhat.com/browse/RHEL-83223

commit 1103579
Author: Michael Margolin <mrgolin@amazon.com>
Date:   Wed Oct 30 09:30:06 2024 +0000

    RDMA/efa: Report link speed according to device attributes

    Set port link speed and width based on max bandwidth acquired from the
    device instead of using constant 100 Gbps. Use a default value in case
    the device didn't set the field.

    Reviewed-by: Daniel Kranzdorf <dkkranzd@amazon.com>
    Reviewed-by: Firas Jahjah <firasj@amazon.com>
    Signed-off-by: Michael Margolin <mrgolin@amazon.com>
    Link: https://patch.msgid.link/20241030093006.21352-1-mrgolin@amazon.com
    Signed-off-by: Leon Romanovsky <leon@kernel.org>

Signed-off-by: Kamal Heib <kheib@redhat.com>

Author: Kamalheib

drivers/infiniband/hw/efa/efa_admin_cmds_defs.h

@@ -718,6 +718,15 @@ struct efa_admin_feature_device_attr_desc {
 
 	/* Unique global ID for an EFA device */
 	u64 guid;
+
+	/* The device maximum link speed in Gbit/sec */
+	u16 max_link_speed_gbps;
+
+	/* MBZ */
+	u16 reserved0;
+
+	/* MBZ */
+	u32 reserved1;
 };
 
 struct efa_admin_feature_queue_attr_desc {

drivers/infiniband/hw/efa/efa_com_cmd.c

@@ -467,6 +467,7 @@ int efa_com_get_device_attr(struct efa_com_dev *edev,
 	result->max_rdma_size = resp.u.device_attr.max_rdma_size;
 	result->device_caps = resp.u.device_attr.device_caps;
 	result->guid = resp.u.device_attr.guid;
+	result->max_link_speed_gbps = resp.u.device_attr.max_link_speed_gbps;
 
 	if (result->admin_api_version < 1) {
 		ibdev_err_ratelimited(

drivers/infiniband/hw/efa/efa_com_cmd.h

@@ -142,6 +142,7 @@ struct efa_com_get_device_attr_result {
 	u16 max_wr_rdma_sge;
 	u16 max_tx_batch;
 	u16 min_sq_depth;
+	u16 max_link_speed_gbps;
 	u8 db_bar;
 };
 

drivers/infiniband/hw/efa/efa_verbs.c

@@ -85,6 +85,8 @@ static const struct rdma_stat_desc efa_port_stats_descs[] = {
 	EFA_DEFINE_PORT_STATS(EFA_STATS_STR)
 };
 
+#define EFA_DEFAULT_LINK_SPEED_GBPS   100
+
 #define EFA_CHUNK_PAYLOAD_SHIFT       12
 #define EFA_CHUNK_PAYLOAD_SIZE        BIT(EFA_CHUNK_PAYLOAD_SHIFT)
 #define EFA_CHUNK_PAYLOAD_PTR_SIZE    8
@@ -277,19 +279,58 @@ int efa_query_device(struct ib_device *ibdev,
 	return 0;
 }
 
+static void efa_link_gbps_to_speed_and_width(u16 gbps,
+					     enum ib_port_speed *speed,
+					     enum ib_port_width *width)
+{
+	if (gbps >= 400) {
+		*width = IB_WIDTH_8X;
+		*speed = IB_SPEED_HDR;
+	} else if (gbps >= 200) {
+		*width = IB_WIDTH_4X;
+		*speed = IB_SPEED_HDR;
+	} else if (gbps >= 120) {
+		*width = IB_WIDTH_12X;
+		*speed = IB_SPEED_FDR10;
+	} else if (gbps >= 100) {
+		*width = IB_WIDTH_4X;
+		*speed = IB_SPEED_EDR;
+	} else if (gbps >= 60) {
+		*width = IB_WIDTH_12X;
+		*speed = IB_SPEED_DDR;
+	} else if (gbps >= 50) {
+		*width = IB_WIDTH_1X;
+		*speed = IB_SPEED_HDR;
+	} else if (gbps >= 40) {
+		*width = IB_WIDTH_4X;
+		*speed = IB_SPEED_FDR10;
+	} else if (gbps >= 30) {
+		*width = IB_WIDTH_12X;
+		*speed = IB_SPEED_SDR;
+	} else {
+		*width = IB_WIDTH_1X;
+		*speed = IB_SPEED_EDR;
+	}
+}
+
 int efa_query_port(struct ib_device *ibdev, u32 port,
 		   struct ib_port_attr *props)
 {
 	struct efa_dev *dev = to_edev(ibdev);
+	enum ib_port_speed link_speed;
+	enum ib_port_width link_width;
+	u16 link_gbps;
 
 	props->lmc = 1;
 
 	props->state = IB_PORT_ACTIVE;
 	props->phys_state = IB_PORT_PHYS_STATE_LINK_UP;
 	props->gid_tbl_len = 1;
 	props->pkey_tbl_len = 1;
-	props->active_speed = IB_SPEED_EDR;
-	props->active_width = IB_WIDTH_4X;
+	link_gbps = dev->dev_attr.max_link_speed_gbps ?: EFA_DEFAULT_LINK_SPEED_GBPS;
+	efa_link_gbps_to_speed_and_width(link_gbps, &link_speed, &link_width);
+	props->active_speed = link_speed;
+	props->active_width = link_width;
 	props->max_mtu = ib_mtu_int_to_enum(dev->dev_attr.mtu);
 	props->active_mtu = ib_mtu_int_to_enum(dev->dev_attr.mtu);
 	props->max_msg_sz = dev->dev_attr.mtu;