net: thunderx: Pause frame support

Enable pause frames on both Rx and Tx side, configure pause
interval e.t.c. Also support for enable/disable pause frames
on Rx/Tx via ethtool has been added.
Signed-off-by: NSunil Goutham <sgoutham@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/cavium/thunder/nic.h

@@ -149,6 +149,12 @@ struct nicvf_rss_info {
 	u64 key[RSS_HASH_KEY_SIZE];
 } ____cacheline_aligned_in_smp;
 
+struct nicvf_pfc {
+	u8    autoneg;
+	u8    fc_rx;
+	u8    fc_tx;
+};
+
 enum rx_stats_reg_offset {
 	RX_OCTS = 0x0,
 	RX_UCAST = 0x1,
@@ -298,6 +304,7 @@ struct nicvf {
 	bool			tns_mode;
 	bool			loopback_supported;
 	struct nicvf_rss_info	rss_info;
+	struct nicvf_pfc	pfc;
 	struct tasklet_struct	qs_err_task;
 	struct work_struct	reset_task;
 
@@ -358,6 +365,7 @@ struct nicvf {
 #define	NIC_MBOX_MSG_SNICVF_PTR		0x15	/* Send sqet nicvf ptr to PVF */
 #define	NIC_MBOX_MSG_LOOPBACK		0x16	/* Set interface in loopback */
 #define	NIC_MBOX_MSG_RESET_STAT_COUNTER 0x17	/* Reset statistics counters */
+#define	NIC_MBOX_MSG_PFC		0x18	/* Pause frame control */
 #define	NIC_MBOX_MSG_CFG_DONE		0xF0	/* VF configuration done */
 #define	NIC_MBOX_MSG_SHUTDOWN		0xF1	/* VF is being shutdown */
 
@@ -500,6 +508,14 @@ struct reset_stat_cfg {
 	u16   sq_stat_mask;
 };
 
+struct pfc {
+	u8    msg;
+	u8    get; /* Get or set PFC settings */
+	u8    autoneg;
+	u8    fc_rx;
+	u8    fc_tx;
+};
+
 /* 128 bit shared memory between PF and each VF */
 union nic_mbx {
 	struct { u8 msg; }	msg;
@@ -518,6 +534,7 @@ union nic_mbx {
 	struct nicvf_ptr	nicvf;
 	struct set_loopback	lbk;
 	struct reset_stat_cfg	reset_stat;
+	struct pfc		pfc;
 };
 
 #define NIC_NODE_ID_MASK	0x03

drivers/net/ethernet/cavium/thunder/nic_main.c

@@ -898,6 +898,30 @@ static void nic_enable_vf(struct nicpf *nic, int vf, bool enable)
 	bgx_lmac_rx_tx_enable(nic->node, bgx, lmac, enable);
 }
 
+static void nic_pause_frame(struct nicpf *nic, int vf, struct pfc *cfg)
+{
+	int bgx, lmac;
+	struct pfc pfc;
+	union nic_mbx mbx = {};
+
+	if (vf >= nic->num_vf_en)
+		return;
+	bgx = NIC_GET_BGX_FROM_VF_LMAC_MAP(nic->vf_lmac_map[vf]);
+	lmac = NIC_GET_LMAC_FROM_VF_LMAC_MAP(nic->vf_lmac_map[vf]);
+
+	if (cfg->get) {
+		bgx_lmac_get_pfc(nic->node, bgx, lmac, &pfc);
+		mbx.pfc.msg = NIC_MBOX_MSG_PFC;
+		mbx.pfc.autoneg = pfc.autoneg;
+		mbx.pfc.fc_rx = pfc.fc_rx;
+		mbx.pfc.fc_tx = pfc.fc_tx;
+		nic_send_msg_to_vf(nic, vf, &mbx);
+	} else {
+		bgx_lmac_set_pfc(nic->node, bgx, lmac, cfg);
+		nic_mbx_send_ack(nic, vf);
+	}
+}
+
 /* Interrupt handler to handle mailbox messages from VFs */
 static void nic_handle_mbx_intr(struct nicpf *nic, int vf)
 {
@@ -1037,6 +1061,9 @@ static void nic_handle_mbx_intr(struct nicpf *nic, int vf)
 	case NIC_MBOX_MSG_RESET_STAT_COUNTER:
 		ret = nic_reset_stat_counters(nic, vf, &mbx.reset_stat);
 		break;
+	case NIC_MBOX_MSG_PFC:
+		nic_pause_frame(nic, vf, &mbx.pfc);
+		goto unlock;
 	default:
 		dev_err(&nic->pdev->dev,
 			"Invalid msg from VF%d, msg 0x%x\n", vf, mbx.msg.msg);

drivers/net/ethernet/cavium/thunder/nicvf_ethtool.c

@@ -720,6 +720,55 @@ static int nicvf_set_channels(struct net_device *dev,
 	return err;
 }
 
+static void nicvf_get_pauseparam(struct net_device *dev,
+				 struct ethtool_pauseparam *pause)
+{
+	struct nicvf *nic = netdev_priv(dev);
+	union nic_mbx mbx = {};
+
+	/* Supported only for 10G/40G interfaces */
+	if ((nic->mac_type == BGX_MODE_SGMII) ||
+	    (nic->mac_type == BGX_MODE_QSGMII) ||
+	    (nic->mac_type == BGX_MODE_RGMII))
+		return;
+
+	mbx.pfc.msg = NIC_MBOX_MSG_PFC;
+	mbx.pfc.get = 1;
+	if (!nicvf_send_msg_to_pf(nic, &mbx)) {
+		pause->autoneg = nic->pfc.autoneg;
+		pause->rx_pause = nic->pfc.fc_rx;
+		pause->tx_pause = nic->pfc.fc_tx;
+	}
+}
+
+static int nicvf_set_pauseparam(struct net_device *dev,
+				struct ethtool_pauseparam *pause)
+{
+	struct nicvf *nic = netdev_priv(dev);
+	union nic_mbx mbx = {};
+
+	/* Supported only for 10G/40G interfaces */
+	if ((nic->mac_type == BGX_MODE_SGMII) ||
+	    (nic->mac_type == BGX_MODE_QSGMII) ||
+	    (nic->mac_type == BGX_MODE_RGMII))
+		return -EOPNOTSUPP;
+
+	if (pause->autoneg)
+		return -EOPNOTSUPP;
+
+	mbx.pfc.msg = NIC_MBOX_MSG_PFC;
+	mbx.pfc.get = 0;
+	mbx.pfc.fc_rx = pause->rx_pause;
+	mbx.pfc.fc_tx = pause->tx_pause;
+	if (nicvf_send_msg_to_pf(nic, &mbx))
+		return -EAGAIN;
+
+	nic->pfc.fc_rx = pause->rx_pause;
+	nic->pfc.fc_tx = pause->tx_pause;
+
+	return 0;
+}
+
 static const struct ethtool_ops nicvf_ethtool_ops = {
 	.get_settings		= nicvf_get_settings,
 	.get_link		= nicvf_get_link,
@@ -741,6 +790,8 @@ static const struct ethtool_ops nicvf_ethtool_ops = {
 	.set_rxfh		= nicvf_set_rxfh,
 	.get_channels		= nicvf_get_channels,
 	.set_channels		= nicvf_set_channels,
+	.get_pauseparam         = nicvf_get_pauseparam,
+	.set_pauseparam         = nicvf_set_pauseparam,
 	.get_ts_info		= ethtool_op_get_ts_info,
 };
 

drivers/net/ethernet/cavium/thunder/nicvf_main.c

@@ -256,6 +256,12 @@ static void  nicvf_handle_mbx_intr(struct nicvf *nic)
 		nic->pnicvf = (struct nicvf *)mbx.nicvf.nicvf;
 		nic->pf_acked = true;
 		break;
+	case NIC_MBOX_MSG_PFC:
+		nic->pfc.autoneg = mbx.pfc.autoneg;
+		nic->pfc.fc_rx = mbx.pfc.fc_rx;
+		nic->pfc.fc_tx = mbx.pfc.fc_tx;
+		nic->pf_acked = true;
+		break;
 	default:
 		netdev_err(nic->netdev,
 			   "Invalid message from PF, msg 0x%x\n", mbx.msg.msg);

drivers/net/ethernet/cavium/thunder/thunder_bgx.c

@@ -212,6 +212,47 @@ void bgx_lmac_rx_tx_enable(int node, int bgx_idx, int lmacid, bool enable)
 }
 EXPORT_SYMBOL(bgx_lmac_rx_tx_enable);
 
+void bgx_lmac_get_pfc(int node, int bgx_idx, int lmacid, void *pause)
+{
+	struct pfc *pfc = (struct pfc *)pause;
+	struct bgx *bgx = bgx_vnic[(node * MAX_BGX_PER_CN88XX) + bgx_idx];
+	struct lmac *lmac;
+	u64 cfg;
+
+	if (!bgx)
+		return;
+	lmac = &bgx->lmac[lmacid];
+	if (lmac->is_sgmii)
+		return;
+
+	cfg = bgx_reg_read(bgx, lmacid, BGX_SMUX_CBFC_CTL);
+	pfc->fc_rx = cfg & RX_EN;
+	pfc->fc_tx = cfg & TX_EN;
+	pfc->autoneg = 0;
+}
+EXPORT_SYMBOL(bgx_lmac_get_pfc);
+
+void bgx_lmac_set_pfc(int node, int bgx_idx, int lmacid, void *pause)
+{
+	struct pfc *pfc = (struct pfc *)pause;
+	struct bgx *bgx = bgx_vnic[(node * MAX_BGX_PER_CN88XX) + bgx_idx];
+	struct lmac *lmac;
+	u64 cfg;
+
+	if (!bgx)
+		return;
+	lmac = &bgx->lmac[lmacid];
+	if (lmac->is_sgmii)
+		return;
+
+	cfg = bgx_reg_read(bgx, lmacid, BGX_SMUX_CBFC_CTL);
+	cfg &= ~(RX_EN | TX_EN);
+	cfg |= (pfc->fc_rx ? RX_EN : 0x00);
+	cfg |= (pfc->fc_tx ? TX_EN : 0x00);
+	bgx_reg_write(bgx, lmacid, BGX_SMUX_CBFC_CTL, cfg);
+}
+EXPORT_SYMBOL(bgx_lmac_set_pfc);
+
 static void bgx_sgmii_change_link_state(struct lmac *lmac)
 {
 	struct bgx *bgx = lmac->bgx;
@@ -525,6 +566,18 @@ static int bgx_lmac_xaui_init(struct bgx *bgx, struct lmac *lmac)
 	cfg |= SMU_TX_CTL_DIC_EN;
 	bgx_reg_write(bgx, lmacid, BGX_SMUX_TX_CTL, cfg);
 
+	/* Enable receive and transmission of pause frames */
+	bgx_reg_write(bgx, lmacid, BGX_SMUX_CBFC_CTL, ((0xffffULL << 32) |
+		      BCK_EN | DRP_EN | TX_EN | RX_EN));
+	/* Configure pause time and interval */
+	bgx_reg_write(bgx, lmacid,
+		      BGX_SMUX_TX_PAUSE_PKT_TIME, DEFAULT_PAUSE_TIME);
+	cfg = bgx_reg_read(bgx, lmacid, BGX_SMUX_TX_PAUSE_PKT_INTERVAL);
+	cfg &= ~0xFFFFull;
+	bgx_reg_write(bgx, lmacid, BGX_SMUX_TX_PAUSE_PKT_INTERVAL,
+		      cfg | (DEFAULT_PAUSE_TIME - 0x1000));
+	bgx_reg_write(bgx, lmacid, BGX_SMUX_TX_PAUSE_ZERO, 0x01);
+
 	/* take lmac_count into account */
 	bgx_reg_modify(bgx, lmacid, BGX_SMUX_TX_THRESH, (0x100 - 1));
 	/* max packet size */

drivers/net/ethernet/cavium/thunder/thunder_bgx.h

@@ -27,6 +27,7 @@
 #define    MAX_BGX_CHANS_PER_LMAC		16
 #define    MAX_DMAC_PER_LMAC			8
 #define    MAX_FRAME_SIZE			9216
+#define    DEFAULT_PAUSE_TIME			0xFFFF
 
 #define	   BGX_ID_MASK				0x3
 
@@ -126,7 +127,10 @@
 #define  SMU_RX_CTL_STATUS			(3ull << 0)
 #define BGX_SMUX_TX_APPEND		0x20100
 #define  SMU_TX_APPEND_FCS_D			BIT_ULL(2)
+#define BGX_SMUX_TX_PAUSE_PKT_TIME	0x20110
 #define BGX_SMUX_TX_MIN_PKT		0x20118
+#define BGX_SMUX_TX_PAUSE_PKT_INTERVAL	0x20120
+#define BGX_SMUX_TX_PAUSE_ZERO		0x20138
 #define BGX_SMUX_TX_INT			0x20140
 #define BGX_SMUX_TX_CTL			0x20178
 #define  SMU_TX_CTL_DIC_EN			BIT_ULL(0)
@@ -136,6 +140,11 @@
 #define BGX_SMUX_CTL			0x20200
 #define  SMU_CTL_RX_IDLE			BIT_ULL(0)
 #define  SMU_CTL_TX_IDLE			BIT_ULL(1)
+#define	BGX_SMUX_CBFC_CTL		0x20218
+#define	RX_EN					BIT_ULL(0)
+#define	TX_EN					BIT_ULL(1)
+#define	BCK_EN					BIT_ULL(2)
+#define	DRP_EN					BIT_ULL(3)
 
 #define BGX_GMP_PCS_MRX_CTL		0x30000
 #define	 PCS_MRX_CTL_RST_AN			BIT_ULL(9)
@@ -207,6 +216,9 @@ void bgx_set_lmac_mac(int node, int bgx_idx, int lmacid, const u8 *mac);
 void bgx_get_lmac_link_state(int node, int bgx_idx, int lmacid, void *status);
 void bgx_lmac_internal_loopback(int node, int bgx_idx,
 				int lmac_idx, bool enable);
+void bgx_lmac_get_pfc(int node, int bgx_idx, int lmacid, void *pause);
+void bgx_lmac_set_pfc(int node, int bgx_idx, int lmacid, void *pause);
+
 void xcv_init_hw(void);
 void xcv_setup_link(bool link_up, int link_speed);