scsi: qla2xxx: Add support for setting port speed

This patch adds sysfs node

1. There is a new sysfs node port_speed
2. The possible values are 2(Auto neg), 8, 16, 32
3. A value outside of the above defaults to Auto neg
4. Any update to the setting causes a link toggle
5. This feature is currently only for ISP27xx

Signed-off-by: Anil Gurumurthy <agurumurthy@marvell.com>
Signed-off-by: Quinn Tran <qtran@marvell.com>
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla2xxx/qla_attr.c

@@ -1632,6 +1632,92 @@ qla2x00_max_speed_sup_show(struct device *dev, struct device_attribute *attr,
 	    ha->max_speed_sup ? "32Gps" : "16Gps");
 }
 
+static ssize_t
+qla2x00_port_speed_store(struct device *dev, struct device_attribute *attr,
+    const char *buf, size_t count)
+{
+	struct scsi_qla_host *vha = shost_priv(dev_to_shost(dev));
+	ulong type, speed;
+	int oldspeed, rval;
+	int mode = QLA_SET_DATA_RATE_LR;
+	struct qla_hw_data *ha = vha->hw;
+
+	if (!IS_QLA27XX(vha->hw)) {
+		ql_log(ql_log_warn, vha, 0x70d8,
+		    "Speed setting not supported \n");
+		return -EINVAL;
+	}
+
+	rval = kstrtol(buf, 10, &type);
+	speed = type;
+	if (type == 40 || type == 80 || type == 160 ||
+	    type == 320) {
+		ql_dbg(ql_dbg_user, vha, 0x70d9,
+		    "Setting will be affected after a loss of sync\n");
+		type = type/10;
+		mode = QLA_SET_DATA_RATE_NOLR;
+	}
+
+	oldspeed = ha->set_data_rate;
+
+	switch (type) {
+	case 0:
+		ha->set_data_rate = PORT_SPEED_AUTO;
+		break;
+	case 4:
+		ha->set_data_rate = PORT_SPEED_4GB;
+		break;
+	case 8:
+		ha->set_data_rate = PORT_SPEED_8GB;
+		break;
+	case 16:
+		ha->set_data_rate = PORT_SPEED_16GB;
+		break;
+	case 32:
+		ha->set_data_rate = PORT_SPEED_32GB;
+		break;
+	default:
+		ql_log(ql_log_warn, vha, 0x1199,
+		    "Unrecognized speed setting:%lx. Setting Autoneg\n",
+		    speed);
+		ha->set_data_rate = PORT_SPEED_AUTO;
+	}
+
+	if (qla2x00_chip_is_down(vha) || (oldspeed == ha->set_data_rate))
+		return -EINVAL;
+
+	ql_log(ql_log_info, vha, 0x70da,
+	    "Setting speed to %lx Gbps \n", type);
+
+	rval = qla2x00_set_data_rate(vha, mode);
+	if (rval != QLA_SUCCESS)
+		return -EIO;
+
+	return strlen(buf);
+}
+
+static ssize_t
+qla2x00_port_speed_show(struct device *dev, struct device_attribute *attr,
+    char *buf)
+{
+	struct scsi_qla_host *vha = shost_priv(dev_to_shost(dev));
+	struct qla_hw_data *ha = vha->hw;
+	ssize_t rval;
+	char *spd[7] = {"0", "0", "0", "4", "8", "16", "32"};
+
+	rval = qla2x00_get_data_rate(vha);
+	if (rval != QLA_SUCCESS) {
+		ql_log(ql_log_warn, vha, 0x70db,
+		    "Unable to get port speed rval:%zd\n", rval);
+		return -EINVAL;
+	}
+
+	ql_log(ql_log_info, vha, 0x70d6,
+	    "port speed:%d\n", ha->link_data_rate);
+
+	return scnprintf(buf, PAGE_SIZE, "%s\n", spd[ha->link_data_rate]);
+}
+
 /* ----- */
 
 static ssize_t
@@ -2128,6 +2214,8 @@ static DEVICE_ATTR_RW(ql2xexchoffld);
 static DEVICE_ATTR_RW(ql2xiniexchg);
 static DEVICE_ATTR(dif_bundle_statistics, 0444,
     qla2x00_dif_bundle_statistics_show, NULL);
+static DEVICE_ATTR(port_speed, 0644, qla2x00_port_speed_show,
+    qla2x00_port_speed_store);
 
 
 struct device_attribute *qla2x00_host_attrs[] = {
@@ -2167,6 +2255,7 @@ struct device_attribute *qla2x00_host_attrs[] = {
 	&dev_attr_max_speed_sup,
 	&dev_attr_zio_threshold,
 	&dev_attr_dif_bundle_statistics,
+	&dev_attr_port_speed,
 	NULL, /* reserve for qlini_mode */
 	NULL, /* reserve for ql2xiniexchg */
 	NULL, /* reserve for ql2xexchoffld */

drivers/scsi/qla2xxx/qla_def.h

@@ -3698,12 +3698,14 @@ struct qla_hw_data {
 #define PORT_SPEED_UNKNOWN 0xFFFF
 #define PORT_SPEED_1GB  0x00
 #define PORT_SPEED_2GB  0x01
+#define PORT_SPEED_AUTO 0x02
 #define PORT_SPEED_4GB  0x03
 #define PORT_SPEED_8GB  0x04
 #define PORT_SPEED_16GB 0x05
 #define PORT_SPEED_32GB 0x06
 #define PORT_SPEED_10GB	0x13
 	uint16_t	link_data_rate;         /* F/W operating speed */
+	uint16_t	set_data_rate;		/* Set by user */
 
 	uint8_t		current_topology;
 	uint8_t		prev_topology;
@@ -4232,6 +4234,10 @@ struct qla_hw_data {
 #define FW_ABILITY_MAX_SPEED(ha)	\
 	(ha->fw_ability_mask & FW_ABILITY_MAX_SPEED_MASK)
 
+#define QLA_GET_DATA_RATE	0
+#define QLA_SET_DATA_RATE_NOLR	1
+#define QLA_SET_DATA_RATE_LR	2 /* Set speed and initiate LR */
+
 /*
  * Qlogic scsi host structure
  */

drivers/scsi/qla2xxx/qla_gbl.h

@@ -899,5 +899,6 @@ void qlt_update_host_map(struct scsi_qla_host *, port_id_t);
 void qlt_remove_target_resources(struct qla_hw_data *);
 void qlt_clr_qp_table(struct scsi_qla_host *vha);
 void qlt_set_mode(struct scsi_qla_host *);
+int qla2x00_set_data_rate(scsi_qla_host_t *vha, uint16_t mode);
 
 #endif /* _QLA_GBL_H */

drivers/scsi/qla2xxx/qla_init.c

@@ -3882,8 +3882,17 @@ qla24xx_config_rings(struct scsi_qla_host *vha)
 		WRT_REG_DWORD(&reg->isp24.rsp_q_in, 0);
 		WRT_REG_DWORD(&reg->isp24.rsp_q_out, 0);
 	}
+
 	qlt_24xx_config_rings(vha);
 
+	/* If the user has configured the speed, set it here */
+	if (ha->set_data_rate) {
+		ql_dbg(ql_dbg_init, vha, 0x00fd,
+		    "Speed set by user : %s Gbps \n",
+		    qla2x00_get_link_speed_str(ha, ha->set_data_rate));
+		icb->firmware_options_3 = (ha->set_data_rate << 13);
+	}
+
 	/* PCI posting */
 	RD_REG_DWORD(&ioreg->hccr);
 }

drivers/scsi/qla2xxx/qla_mbx.c

@@ -5250,6 +5250,66 @@ qla81xx_write_mpi_register(scsi_qla_host_t *vha, uint16_t *mb)
 	return rval;
 }
 
+/* Set the specified data rate */
+int
+qla2x00_set_data_rate(scsi_qla_host_t *vha, uint16_t mode)
+{
+	int rval;
+	mbx_cmd_t mc;
+	mbx_cmd_t *mcp = &mc;
+	struct qla_hw_data *ha = vha->hw;
+	uint16_t val;
+
+	ql_dbg(ql_dbg_mbx + ql_dbg_verbose, vha, 0x1106,
+	    "Entered %s speed:0x%x mode:0x%x.\n", __func__, ha->set_data_rate,
+	    mode);
+
+	if (!IS_FWI2_CAPABLE(ha))
+		return QLA_FUNCTION_FAILED;
+
+	memset(mcp, 0, sizeof(*mcp));
+	switch (ha->set_data_rate) {
+	case PORT_SPEED_AUTO:
+	case PORT_SPEED_4GB:
+	case PORT_SPEED_8GB:
+	case PORT_SPEED_16GB:
+	case PORT_SPEED_32GB:
+		val = ha->set_data_rate;
+		break;
+	default:
+		ql_log(ql_log_warn, vha, 0x1199,
+		    "Unrecognized speed setting:%d. Setting Autoneg\n",
+		    ha->set_data_rate);
+		val = ha->set_data_rate = PORT_SPEED_AUTO;
+		break;
+	}
+
+	mcp->mb[0] = MBC_DATA_RATE;
+	mcp->mb[1] = mode;
+	mcp->mb[2] = val;
+
+	mcp->out_mb = MBX_2|MBX_1|MBX_0;
+	mcp->in_mb = MBX_2|MBX_1|MBX_0;
+	if (IS_QLA83XX(ha) || IS_QLA27XX(ha))
+		mcp->in_mb |= MBX_4|MBX_3;
+	mcp->tov = MBX_TOV_SECONDS;
+	mcp->flags = 0;
+	rval = qla2x00_mailbox_command(vha, mcp);
+	if (rval != QLA_SUCCESS) {
+		ql_dbg(ql_dbg_mbx, vha, 0x1107,
+		    "Failed=%x mb[0]=%x.\n", rval, mcp->mb[0]);
+	} else {
+		if (mcp->mb[1] != 0x7)
+			ql_dbg(ql_dbg_mbx, vha, 0x1179,
+				"Speed set:0x%x\n", mcp->mb[1]);
+
+		ql_dbg(ql_dbg_mbx + ql_dbg_verbose, vha, 0x1108,
+		    "Done %s.\n", __func__);
+	}
+
+	return rval;
+}
+
 int
 qla2x00_get_data_rate(scsi_qla_host_t *vha)
 {
@@ -5265,7 +5325,7 @@ qla2x00_get_data_rate(scsi_qla_host_t *vha)
 		return QLA_FUNCTION_FAILED;
 
 	mcp->mb[0] = MBC_DATA_RATE;
-	mcp->mb[1] = 0;
+	mcp->mb[1] = QLA_GET_DATA_RATE;
 	mcp->out_mb = MBX_1|MBX_0;
 	mcp->in_mb = MBX_2|MBX_1|MBX_0;
 	if (IS_QLA83XX(ha) || IS_QLA27XX(ha))