diff mbox

[net-next] net: dwc-xlgmac: add the initial ethtool support

Message ID f1495b53a7ddd2c4bbccdd4b629f57035139c7b6.1491898365.git.jiedeng@synopsys.com
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Jie Deng April 11, 2017, 8:14 a.m. UTC
It is necessary to provide ethtool support for displaying and
modifying parameters of dwc-xlgmac.

Signed-off-by: Jie Deng <jiedeng@synopsys.com>
---
 drivers/net/ethernet/synopsys/Makefile             |   3 +-
 drivers/net/ethernet/synopsys/dwc-xlgmac-common.c  |   1 +
 drivers/net/ethernet/synopsys/dwc-xlgmac-ethtool.c | 284 +++++++++++++++++++++
 drivers/net/ethernet/synopsys/dwc-xlgmac-hw.c      |   4 +-
 drivers/net/ethernet/synopsys/dwc-xlgmac-net.c     |  22 +-
 drivers/net/ethernet/synopsys/dwc-xlgmac.h         |  11 +
 6 files changed, 321 insertions(+), 4 deletions(-)
 create mode 100644 drivers/net/ethernet/synopsys/dwc-xlgmac-ethtool.c

Comments

David Miller April 11, 2017, 2:47 p.m. UTC | #1
From: Jie Deng <Jie.Deng1@synopsys.com>
Date: Tue, 11 Apr 2017 16:14:04 +0800

> It is necessary to provide ethtool support for displaying and
> modifying parameters of dwc-xlgmac.
> 
> Signed-off-by: Jie Deng <jiedeng@synopsys.com>

I don't see why you cannot allow the statistics to be obtained when
the device is not running.  Similarly for other ethtool calls that
just fetch information stored in the software state of the driver.

I think your ->begin() method is way too restrictive.
Jie Deng April 12, 2017, 5:08 a.m. UTC | #2
On 2017/4/11 22:47, David Miller wrote:

> From: Jie Deng <Jie.Deng1@synopsys.com>
> Date: Tue, 11 Apr 2017 16:14:04 +0800
>
>> It is necessary to provide ethtool support for displaying and
>> modifying parameters of dwc-xlgmac.
>>
>> Signed-off-by: Jie Deng <jiedeng@synopsys.com>
> I don't see why you cannot allow the statistics to be obtained when
> the device is not running.  Similarly for other ethtool calls that
> just fetch information stored in the software state of the driver.
>
> I think your ->begin() method is way too restrictive.
Yeah, begin() seems unreasonable here. I will remove it.
diff mbox

Patch

diff --git a/drivers/net/ethernet/synopsys/Makefile b/drivers/net/ethernet/synopsys/Makefile
index c06e2eb..0ad0191 100644
--- a/drivers/net/ethernet/synopsys/Makefile
+++ b/drivers/net/ethernet/synopsys/Makefile
@@ -4,6 +4,7 @@ 
 
 obj-$(CONFIG_DWC_XLGMAC) += dwc-xlgmac.o
 dwc-xlgmac-objs := dwc-xlgmac-net.o dwc-xlgmac-desc.o \
-		   dwc-xlgmac-hw.o dwc-xlgmac-common.o
+		   dwc-xlgmac-hw.o dwc-xlgmac-common.o \
+		   dwc-xlgmac-ethtool.o
 
 dwc-xlgmac-$(CONFIG_DWC_XLGMAC_PCI) += dwc-xlgmac-pci.o
diff --git a/drivers/net/ethernet/synopsys/dwc-xlgmac-common.c b/drivers/net/ethernet/synopsys/dwc-xlgmac-common.c
index 07def2b..d655a42 100644
--- a/drivers/net/ethernet/synopsys/dwc-xlgmac-common.c
+++ b/drivers/net/ethernet/synopsys/dwc-xlgmac-common.c
@@ -175,6 +175,7 @@  static int xlgmac_init(struct xlgmac_pdata *pdata)
 
 	/* Set device operations */
 	netdev->netdev_ops = xlgmac_get_netdev_ops();
+	netdev->ethtool_ops = xlgmac_get_ethtool_ops();
 
 	/* Set device features */
 	if (pdata->hw_feat.tso) {
diff --git a/drivers/net/ethernet/synopsys/dwc-xlgmac-ethtool.c b/drivers/net/ethernet/synopsys/dwc-xlgmac-ethtool.c
new file mode 100644
index 0000000..8aaabf3
--- /dev/null
+++ b/drivers/net/ethernet/synopsys/dwc-xlgmac-ethtool.c
@@ -0,0 +1,284 @@ 
+/* Synopsys DesignWare Core Enterprise Ethernet (XLGMAC) Driver
+ *
+ * Copyright (c) 2017 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is dual-licensed; you may select either version 2 of
+ * the GNU General Public License ("GPL") or BSD license ("BSD").
+ *
+ * This Synopsys DWC XLGMAC software driver and associated documentation
+ * (hereinafter the "Software") is an unsupported proprietary work of
+ * Synopsys, Inc. unless otherwise expressly agreed to in writing between
+ * Synopsys and you. The Software IS NOT an item of Licensed Software or a
+ * Licensed Product under any End User Software License Agreement or
+ * Agreement for Licensed Products with Synopsys or any supplement thereto.
+ * Synopsys is a registered trademark of Synopsys, Inc. Other names included
+ * in the SOFTWARE may be the trademarks of their respective owners.
+ */
+
+#include <linux/ethtool.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+
+#include "dwc-xlgmac.h"
+#include "dwc-xlgmac-reg.h"
+
+struct xlgmac_stats_desc {
+	char stat_string[ETH_GSTRING_LEN];
+	int stat_offset;
+};
+
+#define XLGMAC_STAT(str, var)					\
+	{							\
+		str,						\
+		offsetof(struct xlgmac_pdata, stats.var),	\
+	}
+
+static const struct xlgmac_stats_desc xlgmac_gstring_stats[] = {
+	/* MMC TX counters */
+	XLGMAC_STAT("tx_bytes", txoctetcount_gb),
+	XLGMAC_STAT("tx_bytes_good", txoctetcount_g),
+	XLGMAC_STAT("tx_packets", txframecount_gb),
+	XLGMAC_STAT("tx_packets_good", txframecount_g),
+	XLGMAC_STAT("tx_unicast_packets", txunicastframes_gb),
+	XLGMAC_STAT("tx_broadcast_packets", txbroadcastframes_gb),
+	XLGMAC_STAT("tx_broadcast_packets_good", txbroadcastframes_g),
+	XLGMAC_STAT("tx_multicast_packets", txmulticastframes_gb),
+	XLGMAC_STAT("tx_multicast_packets_good", txmulticastframes_g),
+	XLGMAC_STAT("tx_vlan_packets_good", txvlanframes_g),
+	XLGMAC_STAT("tx_64_byte_packets", tx64octets_gb),
+	XLGMAC_STAT("tx_65_to_127_byte_packets", tx65to127octets_gb),
+	XLGMAC_STAT("tx_128_to_255_byte_packets", tx128to255octets_gb),
+	XLGMAC_STAT("tx_256_to_511_byte_packets", tx256to511octets_gb),
+	XLGMAC_STAT("tx_512_to_1023_byte_packets", tx512to1023octets_gb),
+	XLGMAC_STAT("tx_1024_to_max_byte_packets", tx1024tomaxoctets_gb),
+	XLGMAC_STAT("tx_underflow_errors", txunderflowerror),
+	XLGMAC_STAT("tx_pause_frames", txpauseframes),
+
+	/* MMC RX counters */
+	XLGMAC_STAT("rx_bytes", rxoctetcount_gb),
+	XLGMAC_STAT("rx_bytes_good", rxoctetcount_g),
+	XLGMAC_STAT("rx_packets", rxframecount_gb),
+	XLGMAC_STAT("rx_unicast_packets_good", rxunicastframes_g),
+	XLGMAC_STAT("rx_broadcast_packets_good", rxbroadcastframes_g),
+	XLGMAC_STAT("rx_multicast_packets_good", rxmulticastframes_g),
+	XLGMAC_STAT("rx_vlan_packets", rxvlanframes_gb),
+	XLGMAC_STAT("rx_64_byte_packets", rx64octets_gb),
+	XLGMAC_STAT("rx_65_to_127_byte_packets", rx65to127octets_gb),
+	XLGMAC_STAT("rx_128_to_255_byte_packets", rx128to255octets_gb),
+	XLGMAC_STAT("rx_256_to_511_byte_packets", rx256to511octets_gb),
+	XLGMAC_STAT("rx_512_to_1023_byte_packets", rx512to1023octets_gb),
+	XLGMAC_STAT("rx_1024_to_max_byte_packets", rx1024tomaxoctets_gb),
+	XLGMAC_STAT("rx_undersize_packets_good", rxundersize_g),
+	XLGMAC_STAT("rx_oversize_packets_good", rxoversize_g),
+	XLGMAC_STAT("rx_crc_errors", rxcrcerror),
+	XLGMAC_STAT("rx_crc_errors_small_packets", rxrunterror),
+	XLGMAC_STAT("rx_crc_errors_giant_packets", rxjabbererror),
+	XLGMAC_STAT("rx_length_errors", rxlengtherror),
+	XLGMAC_STAT("rx_out_of_range_errors", rxoutofrangetype),
+	XLGMAC_STAT("rx_fifo_overflow_errors", rxfifooverflow),
+	XLGMAC_STAT("rx_watchdog_errors", rxwatchdogerror),
+	XLGMAC_STAT("rx_pause_frames", rxpauseframes),
+
+	/* Extra counters */
+	XLGMAC_STAT("tx_tso_packets", tx_tso_packets),
+	XLGMAC_STAT("rx_split_header_packets", rx_split_header_packets),
+	XLGMAC_STAT("tx_process_stopped", tx_process_stopped),
+	XLGMAC_STAT("rx_process_stopped", rx_process_stopped),
+	XLGMAC_STAT("tx_buffer_unavailable", tx_buffer_unavailable),
+	XLGMAC_STAT("rx_buffer_unavailable", rx_buffer_unavailable),
+	XLGMAC_STAT("fatal_bus_error", fatal_bus_error),
+	XLGMAC_STAT("tx_vlan_packets", tx_vlan_packets),
+	XLGMAC_STAT("rx_vlan_packets", rx_vlan_packets),
+	XLGMAC_STAT("napi_poll_isr", napi_poll_isr),
+	XLGMAC_STAT("napi_poll_txtimer", napi_poll_txtimer),
+};
+
+#define XLGMAC_STATS_COUNT	ARRAY_SIZE(xlgmac_gstring_stats)
+
+static int xlgmac_ethtool_begin(struct net_device *netdev)
+{
+	if (!netif_running(netdev))
+		return -ENODEV;
+
+	return 0;
+}
+
+static void xlgmac_ethtool_get_drvinfo(struct net_device *netdev,
+				       struct ethtool_drvinfo *drvinfo)
+{
+	struct xlgmac_pdata *pdata = netdev_priv(netdev);
+	u32 ver = pdata->hw_feat.version;
+	u32 snpsver, devid, userver;
+
+	strlcpy(drvinfo->driver, pdata->drv_name, sizeof(drvinfo->driver));
+	strlcpy(drvinfo->version, pdata->drv_ver, sizeof(drvinfo->version));
+	strlcpy(drvinfo->bus_info, dev_name(pdata->dev),
+		sizeof(drvinfo->bus_info));
+	/* S|SNPSVER: Synopsys-defined Version
+	 * D|DEVID: Indicates the Device family
+	 * U|USERVER: User-defined Version
+	 */
+	snpsver = XLGMAC_GET_REG_BITS(ver, MAC_VR_SNPSVER_POS,
+				      MAC_VR_SNPSVER_LEN);
+	devid = XLGMAC_GET_REG_BITS(ver, MAC_VR_DEVID_POS,
+				    MAC_VR_DEVID_LEN);
+	userver = XLGMAC_GET_REG_BITS(ver, MAC_VR_USERVER_POS,
+				      MAC_VR_USERVER_LEN);
+	snprintf(drvinfo->fw_version, sizeof(drvinfo->fw_version),
+		 "S.D.U: %x.%x.%x", snpsver, devid, userver);
+}
+
+static u32 xlgmac_ethtool_get_msglevel(struct net_device *netdev)
+{
+	struct xlgmac_pdata *pdata = netdev_priv(netdev);
+
+	return pdata->msg_enable;
+}
+
+static void xlgmac_ethtool_set_msglevel(struct net_device *netdev,
+					u32 msglevel)
+{
+	struct xlgmac_pdata *pdata = netdev_priv(netdev);
+
+	pdata->msg_enable = msglevel;
+}
+
+static void xlgmac_ethtool_get_channels(struct net_device *netdev,
+					struct ethtool_channels *channel)
+{
+	struct xlgmac_pdata *pdata = netdev_priv(netdev);
+
+	channel->max_rx = XLGMAC_MAX_DMA_CHANNELS;
+	channel->max_tx = XLGMAC_MAX_DMA_CHANNELS;
+	channel->rx_count = pdata->rx_q_count;
+	channel->tx_count = pdata->tx_q_count;
+}
+
+static int xlgmac_ethtool_get_coalesce(struct net_device *netdev,
+				       struct ethtool_coalesce *ec)
+{
+	struct xlgmac_pdata *pdata = netdev_priv(netdev);
+
+	memset(ec, 0, sizeof(struct ethtool_coalesce));
+	ec->rx_coalesce_usecs = pdata->rx_usecs;
+	ec->rx_max_coalesced_frames = pdata->rx_frames;
+	ec->tx_max_coalesced_frames = pdata->tx_frames;
+
+	return 0;
+}
+
+static int xlgmac_ethtool_set_coalesce(struct net_device *netdev,
+				       struct ethtool_coalesce *ec)
+{
+	struct xlgmac_pdata *pdata = netdev_priv(netdev);
+	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
+	unsigned int rx_frames, rx_riwt, rx_usecs;
+	unsigned int tx_frames;
+
+	/* Check for not supported parameters */
+	if ((ec->rx_coalesce_usecs_irq) || (ec->rx_max_coalesced_frames_irq) ||
+	    (ec->tx_coalesce_usecs) || (ec->tx_coalesce_usecs_high) ||
+	    (ec->tx_max_coalesced_frames_irq) || (ec->tx_coalesce_usecs_irq) ||
+	    (ec->stats_block_coalesce_usecs) ||  (ec->pkt_rate_low) ||
+	    (ec->use_adaptive_rx_coalesce) || (ec->use_adaptive_tx_coalesce) ||
+	    (ec->rx_max_coalesced_frames_low) || (ec->rx_coalesce_usecs_low) ||
+	    (ec->tx_coalesce_usecs_low) || (ec->tx_max_coalesced_frames_low) ||
+	    (ec->pkt_rate_high) || (ec->rx_coalesce_usecs_high) ||
+	    (ec->rx_max_coalesced_frames_high) ||
+	    (ec->tx_max_coalesced_frames_high) ||
+	    (ec->rate_sample_interval))
+		return -EOPNOTSUPP;
+
+	rx_usecs = ec->rx_coalesce_usecs;
+	rx_riwt = hw_ops->usec_to_riwt(pdata, rx_usecs);
+	rx_frames = ec->rx_max_coalesced_frames;
+	tx_frames = ec->tx_max_coalesced_frames;
+
+	if ((rx_riwt > XLGMAC_MAX_DMA_RIWT) ||
+	    (rx_riwt < XLGMAC_MIN_DMA_RIWT) ||
+	    (rx_frames > pdata->rx_desc_count))
+		return -EINVAL;
+
+	if (tx_frames > pdata->tx_desc_count)
+		return -EINVAL;
+
+	pdata->rx_riwt = rx_riwt;
+	pdata->rx_usecs = rx_usecs;
+	pdata->rx_frames = rx_frames;
+	hw_ops->config_rx_coalesce(pdata);
+
+	pdata->tx_frames = tx_frames;
+	hw_ops->config_tx_coalesce(pdata);
+
+	return 0;
+}
+
+static void xlgmac_ethtool_get_strings(struct net_device *netdev,
+				       u32 stringset, u8 *data)
+{
+	int i;
+
+	switch (stringset) {
+	case ETH_SS_STATS:
+		for (i = 0; i < XLGMAC_STATS_COUNT; i++) {
+			memcpy(data, xlgmac_gstring_stats[i].stat_string,
+			       ETH_GSTRING_LEN);
+			data += ETH_GSTRING_LEN;
+		}
+		break;
+	default:
+		WARN_ON(1);
+		break;
+	}
+}
+
+static int xlgmac_ethtool_get_sset_count(struct net_device *netdev,
+					 int stringset)
+{
+	int ret;
+
+	switch (stringset) {
+	case ETH_SS_STATS:
+		ret = XLGMAC_STATS_COUNT;
+		break;
+
+	default:
+		ret = -EOPNOTSUPP;
+	}
+
+	return ret;
+}
+
+static void xlgmac_ethtool_get_ethtool_stats(struct net_device *netdev,
+					     struct ethtool_stats *stats,
+					     u64 *data)
+{
+	struct xlgmac_pdata *pdata = netdev_priv(netdev);
+	u8 *stat;
+	int i;
+
+	pdata->hw_ops.read_mmc_stats(pdata);
+	for (i = 0; i < XLGMAC_STATS_COUNT; i++) {
+		stat = (u8 *)pdata + xlgmac_gstring_stats[i].stat_offset;
+		*data++ = *(u64 *)stat;
+	}
+}
+
+static const struct ethtool_ops xlgmac_ethtool_ops = {
+	.begin = xlgmac_ethtool_begin,
+	.get_drvinfo = xlgmac_ethtool_get_drvinfo,
+	.get_link = ethtool_op_get_link,
+	.get_msglevel = xlgmac_ethtool_get_msglevel,
+	.set_msglevel = xlgmac_ethtool_set_msglevel,
+	.get_channels = xlgmac_ethtool_get_channels,
+	.get_coalesce = xlgmac_ethtool_get_coalesce,
+	.set_coalesce = xlgmac_ethtool_set_coalesce,
+	.get_strings = xlgmac_ethtool_get_strings,
+	.get_sset_count = xlgmac_ethtool_get_sset_count,
+	.get_ethtool_stats = xlgmac_ethtool_get_ethtool_stats,
+};
+
+const struct ethtool_ops *xlgmac_get_ethtool_ops(void)
+{
+	return &xlgmac_ethtool_ops;
+}
diff --git a/drivers/net/ethernet/synopsys/dwc-xlgmac-hw.c b/drivers/net/ethernet/synopsys/dwc-xlgmac-hw.c
index 0dec1dc..458a784 100644
--- a/drivers/net/ethernet/synopsys/dwc-xlgmac-hw.c
+++ b/drivers/net/ethernet/synopsys/dwc-xlgmac-hw.c
@@ -835,12 +835,14 @@  static void xlgmac_dev_xmit(struct xlgmac_channel *channel)
 				desc_data->skb_dma_len);
 
 	/* VLAN tag insertion check */
-	if (vlan)
+	if (vlan) {
 		dma_desc->desc2 = XLGMAC_SET_REG_BITS_LE(
 					dma_desc->desc2,
 					TX_NORMAL_DESC2_VTIR_POS,
 					TX_NORMAL_DESC2_VTIR_LEN,
 					TX_NORMAL_DESC2_VLAN_INSERT);
+		pdata->stats.tx_vlan_packets++;
+	}
 
 	/* Timestamp enablement check */
 	if (XLGMAC_GET_REG_BITS(pkt_info->attributes,
diff --git a/drivers/net/ethernet/synopsys/dwc-xlgmac-net.c b/drivers/net/ethernet/synopsys/dwc-xlgmac-net.c
index 6acf86c..3b91257 100644
--- a/drivers/net/ethernet/synopsys/dwc-xlgmac-net.c
+++ b/drivers/net/ethernet/synopsys/dwc-xlgmac-net.c
@@ -290,19 +290,34 @@  static irqreturn_t xlgmac_isr(int irq, void *data)
 				/* Disable Tx and Rx interrupts */
 				xlgmac_disable_rx_tx_ints(pdata);
 
+				pdata->stats.napi_poll_isr++;
 				/* Turn on polling */
 				__napi_schedule_irqoff(&pdata->napi);
 			}
 		}
 
+		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_TPS_POS,
+					DMA_CH_SR_TPS_LEN))
+			pdata->stats.tx_process_stopped++;
+
+		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_RPS_POS,
+					DMA_CH_SR_RPS_LEN))
+			pdata->stats.rx_process_stopped++;
+
+		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_TBU_POS,
+					DMA_CH_SR_TBU_LEN))
+			pdata->stats.tx_buffer_unavailable++;
+
 		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_RBU_POS,
 					DMA_CH_SR_RBU_LEN))
 			pdata->stats.rx_buffer_unavailable++;
 
 		/* Restart the device on a Fatal Bus Error */
 		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_FBE_POS,
-					DMA_CH_SR_FBE_LEN))
+					DMA_CH_SR_FBE_LEN)) {
+			pdata->stats.fatal_bus_error++;
 			schedule_work(&pdata->restart_work);
+		}
 
 		/* Clear all interrupt signals */
 		writel(dma_ch_isr, XLGMAC_DMA_REG(channel, DMA_CH_SR));
@@ -357,6 +372,7 @@  static void xlgmac_tx_timer(unsigned long data)
 		else
 			xlgmac_disable_rx_tx_ints(pdata);
 
+		pdata->stats.napi_poll_txtimer++;
 		/* Turn on polling */
 		__napi_schedule(napi);
 	}
@@ -1225,9 +1241,11 @@  static int xlgmac_rx_poll(struct xlgmac_channel *channel, int budget)
 
 		if (XLGMAC_GET_REG_BITS(pkt_info->attributes,
 					RX_PACKET_ATTRIBUTES_VLAN_CTAG_POS,
-				    RX_PACKET_ATTRIBUTES_VLAN_CTAG_LEN))
+				    RX_PACKET_ATTRIBUTES_VLAN_CTAG_LEN)) {
 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 					       pkt_info->vlan_ctag);
+			pdata->stats.rx_vlan_packets++;
+		}
 
 		if (XLGMAC_GET_REG_BITS(pkt_info->attributes,
 					RX_PACKET_ATTRIBUTES_RSS_HASH_POS,
diff --git a/drivers/net/ethernet/synopsys/dwc-xlgmac.h b/drivers/net/ethernet/synopsys/dwc-xlgmac.h
index 676b2fb8..cab3e40 100644
--- a/drivers/net/ethernet/synopsys/dwc-xlgmac.h
+++ b/drivers/net/ethernet/synopsys/dwc-xlgmac.h
@@ -67,6 +67,8 @@ 
 #define XLGMAC_INIT_DMA_TX_FRAMES	25
 #define XLGMAC_INIT_DMA_RX_USECS	30
 #define XLGMAC_INIT_DMA_RX_FRAMES	25
+#define XLGMAC_MAX_DMA_RIWT		0xff
+#define XLGMAC_MIN_DMA_RIWT		0x01
 
 /* Flow control queue count */
 #define XLGMAC_MAX_FLOW_CONTROL_QUEUES	8
@@ -190,7 +192,15 @@  struct xlgmac_stats {
 	/* Extra counters */
 	u64 tx_tso_packets;
 	u64 rx_split_header_packets;
+	u64 tx_process_stopped;
+	u64 rx_process_stopped;
+	u64 tx_buffer_unavailable;
 	u64 rx_buffer_unavailable;
+	u64 fatal_bus_error;
+	u64 tx_vlan_packets;
+	u64 rx_vlan_packets;
+	u64 napi_poll_isr;
+	u64 napi_poll_txtimer;
 };
 
 struct xlgmac_ring_buf {
@@ -622,6 +632,7 @@  struct xlgmac_pdata {
 void xlgmac_init_desc_ops(struct xlgmac_desc_ops *desc_ops);
 void xlgmac_init_hw_ops(struct xlgmac_hw_ops *hw_ops);
 const struct net_device_ops *xlgmac_get_netdev_ops(void);
+const struct ethtool_ops *xlgmac_get_ethtool_ops(void);
 void xlgmac_dump_tx_desc(struct xlgmac_pdata *pdata,
 			 struct xlgmac_ring *ring,
 			 unsigned int idx,