[very-RFC 3/8] Adding TSN-driver to Intel I210 controller

Henrik Austad
2016-06-11T23:01:43Z

This adds support for loading the igb.ko module with tsn
capabilities. This requires a 2-step approach. First enabling TSN in
.config, then load the module with use_tsn=1.

Once enabled and loaded, the controller will be placed in "Qav-mode"
which is when the credit-based shaper is available, 3 of the queues are
removed from regular traffic, max payload is set to 1522 octets (no
jumboframes allowed).

It dumps the registers of interest before and after, so this clutters
kern.log a bit. In time this will be reduced / tied to the debug-param
for the module.

Note: currently this driver is *not* stable, it is still a work in
progress.

Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: intel-wired-lan@lists.osuosl.org
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Henrik Austad <haustad@cisco.com>
---
drivers/net/ethernet/intel/Kconfig | 18 ++
drivers/net/ethernet/intel/igb/Makefile | 2 +-
drivers/net/ethernet/intel/igb/igb.h | 19 ++
drivers/net/ethernet/intel/igb/igb_main.c | 10 +-
drivers/net/ethernet/intel/igb/igb_tsn.c | 396 ++++++++++++++++++++++++++++++
5 files changed, 443 insertions(+), 2 deletions(-)
create mode 100644 drivers/net/ethernet/intel/igb/igb_tsn.c

diff --git a/drivers/net/ethernet/intel/Kconfig b/drivers/net/ethernet/intel/Kconfig
index 714bd10..8e620a9 100644
--- a/drivers/net/ethernet/intel/Kconfig
+++ b/drivers/net/ethernet/intel/Kconfig
@@ -99,6 +99,24 @@ config IGB
To compile this driver as a module, choose M here. The module
will be called igb.

+config IGB_TSN
+ tristate "TSN Support for Intel(R) 82575/82576 i210 Network Controller"
+ depends on IGB && TSN
+ ---help---
+ This driver supports TSN (AVB) on Intel I210 network controllers.
+
+ When enabled, it will allow the module to be loaded with
+ "use_tsn" which will initialize the controller to A/V-mode
+ instead of legacy-mode. This will take 3 of the tx-queues and
+ place them in 802.1Q QoS mode and enable the credit-based
+ shaper for 2 of the queues.
+
+ If built with this option, but not loaded with use_tsn, the
+ only difference is a slightly larger module, no extra
+ code paths are called.
+
+ If unsure, say No
+
config IGB_HWMON
bool "Intel(R) PCI-Express Gigabit adapters HWMON support"
default y
diff --git a/drivers/net/ethernet/intel/igb/Makefile b/drivers/net/ethernet/intel/igb/Makefile
index 5bcb2de..1a9b776 100644
--- a/drivers/net/ethernet/intel/igb/Makefile
+++ b/drivers/net/ethernet/intel/igb/Makefile
@@ -33,4 +33,4 @@ obj-$(CONFIG_IGB) += igb.o

igb-objs := igb_main.o igb_ethtool.o e1000_82575.o \
e1000_mac.o e1000_nvm.o e1000_phy.o e1000_mbx.o \
- e1000_i210.o igb_ptp.o igb_hwmon.o
+ e1000_i210.o igb_ptp.o igb_hwmon.o igb_tsn.o
diff --git a/drivers/net/ethernet/intel/igb/igb.h b/drivers/net/ethernet/intel/igb/igb.h
index b9609af..708f705 100644
--- a/drivers/net/ethernet/intel/igb/igb.h
+++ b/drivers/net/ethernet/intel/igb/igb.h
@@ -356,6 +356,7 @@ struct hwmon_buff {
#define IGB_RETA_SIZE 128

/* board specific private data structure */
+
struct igb_adapter {
unsigned long active_vlans[BITS_TO_LONGS(VLAN_N_VID)];

@@ -472,6 +473,13 @@ struct igb_adapter {
int copper_tries;
struct e1000_info ei;
u16 eee_advert;
+
+#if IS_ENABLED(CONFIG_IGB_TSN)
+ /* Reserved BW for class A and B */
+ u16 sra_idleslope_res;
+ u16 srb_idleslope_res;
+ u8 tsn_ready:1;
+#endif /* IGB_TSN */
};

#define IGB_FLAG_HAS_MSI BIT(0)
@@ -552,6 +560,17 @@ void igb_ptp_rx_pktstamp(struct igb_q_vector *q_vector, unsigned char *va,
struct sk_buff *skb);
int igb_ptp_set_ts_config(struct net_device *netdev, struct ifreq *ifr);
int igb_ptp_get_ts_config(struct net_device *netdev, struct ifreq *ifr);
+/* This should be the only place where we add ifdeffery
+ * to include tsn-stuff or not. Everything else is located in igb_tsn.c
+ */
+#if IS_ENABLED(CONFIG_IGB_TSN)
+void igb_tsn_init(struct igb_adapter *adapter);
+int igb_tsn_capable(struct net_device *netdev);
+int igb_tsn_link_configure(struct net_device *netdev, enum sr_class sr_class,
+ u16 framesize, u16 vid);
+#else
+static inline void igb_tsn_init(struct igb_adapter *adapter) { }
+#endif /* CONFIG_IGB_TSN */
void igb_set_flag_queue_pairs(struct igb_adapter *, const u32);
#ifdef CONFIG_IGB_HWMON
void igb_sysfs_exit(struct igb_adapter *adapter);
diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index ef3d642..4d8789f 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -2142,6 +2142,10 @@ static const struct net_device_ops igb_netdev_ops = {
#ifdef CONFIG_NET_POLL_CONTROLLER
.ndo_poll_controller = igb_netpoll,
#endif
+#if IS_ENABLED(CONFIG_IGB_TSN)
+ .ndo_tsn_capable = igb_tsn_capable,
+ .ndo_tsn_link_configure = igb_tsn_link_configure,
+#endif /* CONFIG_IGB_TSN */
.ndo_fix_features = igb_fix_features,
.ndo_set_features = igb_set_features,
.ndo_fdb_add = igb_ndo_fdb_add,
@@ -2665,6 +2669,8 @@ static int igb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
/* do hw tstamp init after resetting */
igb_ptp_init(adapter);

+ igb_tsn_init(adapter);
+
dev_info(&pdev->dev, "Intel(R) Gigabit Ethernet Network Connection\n");
/* print bus type/speed/width info, not applicable to i354 */
if (hw->mac.type != e1000_i354) {
@@ -5323,8 +5329,10 @@ static netdev_tx_t igb_xmit_frame(struct sk_buff *skb,
/* The minimum packet size with TCTL.PSP set is 17 so pad the skb
* in order to meet this minimum size requirement.
*/
- if (skb_put_padto(skb, 17))
+ if (skb_put_padto(skb, 17)) {
+ pr_err("%s: skb_put_padto FAILED. skb->len < 17\n", __func__);
return NETDEV_TX_OK;
+ }

return igb_xmit_frame_ring(skb, igb_tx_queue_mapping(adapter, skb));
}
diff --git a/drivers/net/ethernet/intel/igb/igb_tsn.c b/drivers/net/ethernet/intel/igb/igb_tsn.c
new file mode 100644
index 0000000..641f4f2
--- /dev/null
+++ b/drivers/net/ethernet/intel/igb/igb_tsn.c
@@ -0,0 +1,396 @@
+/*
+ * Copyright(c) 2015-2016 Henrik Austad <haustad@cisco.com>
+ * Cisco Systems, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+/* FIXME: This should probably be handled by some Makefile-magic */
+
+#if IS_ENABLED(CONFIG_IGB_TSN)
+#include "igb.h"
+#include <linux/module.h>
+
+/* NOTE: keep the defines not present in e1000_regs.h to avoid
+ * cluttering too many files. Once we are pretty stable, these will move
+ * into it's proper home. Until then, make merge a bit easier by
+ * avoiding it
+ */
+
+/* Qav regs */
+#define E1000_IRPBS 0x02404 /* Rx Packet Buffer Size - RW */
+#define E1000_ITPBS 0x03404 /* Tx buffer size assignment */
+#define E1000_TQAVCTRL 0x03570 /* Tx Qav Control */
+#define E1000_DTXMXPKTSZ 0x0355C /* DMA TX Maximum Packet Size */
+
+/* Qav defines. */
+#define E1000_TQAVCH_ZERO_CREDIT 0x80000000
+#define E1000_LINK_RATE 0x7735
+
+/* queue mode, 0=strict, 1=SR mode */
+#define E1000_TQAVCC_QUEUEMODE 0x80000000
+/* Transmit mode, 0=legacy, 1=QAV */
+#define E1000_TQAVCTRL_TXMODE 0x00000001
+/* report DMA time of tx packets */
+#define E1000_TQAVCTRL_1588_STAT_EN 0x00000004
+/* data fetch arbitration */
+#define E1000_TQAVCTRL_DATA_FETCH_ARB 0x00000010
+/* data tx arbitration */
+#define E1000_TQAVCTRL_DATA_TRAN_ARB 0x00000100
+/* data launch time valid */
+#define E1000_TQAVCTRL_DATA_TRAN_TIM 0x00000200
+/* stall SP to guarantee SR */
+#define E1000_TQAVCTRL_SP_WAIT_SR 0x00000400
+
+/* ... and associated shift value */
+#define E1000_TQAVCTRL_FETCH_TM_SHIFT (16)
+
+/* QAV Tx mode control registers where _n can be 0 or 1. */
+#define E1000_TQAVCC(_idx) (0x03004 + 0x40 * (_idx))
+
+/* Tx Qav High Credit - See 7.2.7.6 for calculations
+ * intel 8.12.18
+ */
+#define E1000_TQAVHC(_idx) (0x0300C + 0x40 * (_idx))
+
+/* Queues priority masks where _n and _p can be 0-3. */
+
+#define MAX_FRAME_SIZE 1522
+#define MIN_FRAME_SIZE 64
+
+static int use_tsn = -1;
+static int debug_tsn = -1;
+module_param(use_tsn, int, 0);
+module_param(debug_tsn, int, 0);
+MODULE_PARM_DESC(use_tsn, "use_tsn (0=off, 1=enabled)");
+MODULE_PARM_DESC(debug_tsn, "debug_tsn (0=off, 1=enabled)");
+
+/* For a full list of the registers dumped here, see sec 8.1.3 in the
+ * i210 controller datasheet.
+ */
+static inline void _tsn_dump_regs(struct igb_adapter *adapter)
+{
+ u32 val = 0;
+ struct device *dev;
+ struct e1000_hw *hw = &adapter->hw;
+
+ /* do not dump regs if we're not debugging driver */
+ if (debug_tsn != 1)
+ return;
+
+ dev = &adapter->pdev->dev;
+ dev_info(dev, "num_tx_queues=%d, num_rx_queues=%d\n",
+ adapter->num_tx_queues, adapter->num_rx_queues);
+
+ /* 0x0008 - E1000_STATUS Device status register */
+ val = rd32(E1000_STATUS);
+ dev_info(&adapter->pdev->dev, "\n");
+ dev_info(dev, "Status: FullDuplex=%s, LinkUp=%s, speed=%0x01x\n",
+ val & 0x1 ? "FD" : "HD",
+ val & 0x2 ? "LU" : "LD",
+ val & 0xc0 >> 6);
+
+ /* E1000_VET vlan ether type */
+ val = rd32(E1000_VET);
+ dev_info(dev, "VLAN ether type: VET.VET=0x%04x, VET.VET_EXT=0x%04x\n",
+ val & 0xffff, (val >> 16) & 0xffff);
+
+ /* E1000_RXPBS (RXPBSIZE) Rx Packet Buffer Size */
+ val = rd32(E1000_RXPBS);
+ dev_info(dev, "Rx Packet buffer: RXPBSIZE=%dkB, Bmc2ospbsize=%dkB, cfg_ts_en=%s\n",
+ val & 0x1f,
+ (val >> 6) & 0x1f,
+ (val & (1 << 31)) ? "cfg_ts_en" : "cfg_ts_dis");
+
+ /* Transmit stuff */
+ /* E1000_TXPBS (TXPBSIZE) Tx Packet Buffer Size - RW */
+ val = rd32(E1000_TXPBS);
+ dev_info(dev, "Tx Packet buffer: Txpb0size=%dkB, Txpb1size=%dkB, Txpb2size=%dkB, Txpb3size=%dkB, os2Bmcpbsize=%dkB\n",
+ val & 0x3f, (val >> 6) & 0x3f, (val >> 12) & 0x3f,
+ (val >> 18) & 0x3f, (val >> 24) & 0x3f);
+
+ /* E1000_TCTL (TCTL) Tx control - RW*/
+ val = rd32(E1000_TCTL);
+ dev_info(dev, "Tx control reg: TxEnable=%s, CT=0x%X\n",
+ val & 2 ? "EN" : "DIS", (val >> 3) & 0x3F);
+
+ /* TQAVHC : Transmit Qav High credits 0x300C + 0x40*n - RW */
+ val = rd32(E1000_TQAVHC(0));
+ dev_info(dev, "E1000_TQAVHC0: %0x08x\n", val);
+ val = rd32(E1000_TQAVHC(1));
+ dev_info(dev, "E1000_TQAVHC1: %0x08x\n", val);
+
+ /* TQAVCC[0-1]: Transmit Qav 0x3004 + 0x40*n - RW */
+ val = rd32(E1000_TQAVCC(0));
+ dev_info(dev, "E1000_TQAVCC0: idleSlope=%02x, QueueMode=%s\n",
+ val % 0xff,
+ val > 31 ? "Stream reservation" : "Strict priority");
+ val = rd32(E1000_TQAVCC(1));
+ dev_info(dev, "E1000_TQAVCC1: idleSlope=%02x, QueueMode=%s\n",
+ val % 0xff,
+ val > 31 ? "Stream reservation" : "Strict priority");
+
+ /* TQAVCTRL : Transmit Qav control - RW */
+ val = rd32(E1000_TQAVCTRL);
+ dev_info(dev, "E1000_TQAVCTRL: TransmitMode=%s,1588_STAT_EN=%s,DataFetchARB=%s,DataTranARB=%s,DataTranTIM=%s,SP_WAIT_SR=%s,FetchTimDelta=%dns (0x%04x)\n",
+ (val & 0x0001) ? "Qav" : "Legacy",
+ (val & 0x0004) ? "En" : "Dis",
+ (val & 0x0010) ? "Most Empty" : "Round Robin",
+ (val & 0x0100) ? "Credit Shaper" : "Strict priority",
+ (val & 0x0200) ? "Valid" : "N/A",
+ (val & 0x0400) ? "Wait" : "nowait",
+ (val >> 16) * 32, (val >> 16));
+}
+
+/* Place the NIC in Qav-mode.
+ *
+ * This will result in a _single_ queue for normal BE traffic, the rest
+ * will be grabbed by the Qav-machinery and kept for strict priority
+ * transmission.
+ *
+ * I210 Datasheet Sec 7.2.7.7 gives a lot of information.
+ */
+void igb_tsn_init(struct igb_adapter *adapter)
+{
+ struct e1000_hw *hw = &adapter->hw;
+ u32 val;
+
+ if (use_tsn != 1) {
+ adapter->tsn_ready = 0;
+ dev_info(&adapter->pdev->dev, "%s got use_tsn > 0 (%d)\n",
+ __func__, use_tsn);
+ return;
+ }
+
+ if (debug_tsn < 0 || debug_tsn > 1)
+ debug_tsn = 0;
+
+ if (!adapter->pdev) {
+ adapter->tsn_ready = 0;
+ return;
+ }
+
+ switch (adapter->pdev->device) {
+ case 0x1533: /* E1000_DEV_ID_I210_COPPER */
+ case 0x1536: /* E1000_DEV_ID_I210_FIBER */
+ case 0x1537: /* E1000_DEV_ID_I210_SERDES: */
+ case 0x1538: /* E1000_DEV_ID_I210_SGMII: */
+ case 0x157b: /* E1000_DEV_ID_I210_COPPER_FLASHLESS: */
+ case 0x157c: /* E1000_DEV_ID_I210_SERDES_FLASHLESS: */
+ break;
+ default:
+ /* not a known IGB-TSN capable device */
+ adapter->tsn_ready = 0;
+ return;
+ }
+ _tsn_dump_regs(adapter);
+
+ /* Set Tx packet buffer size assignment, see 7.2.7.7 in i210
+ * PB0: 8kB
+ * PB1: 8kB
+ * PB2: 4kB
+ * PB3: 4kB
+ * os2bmcsize: 2kB
+ * sumTx: 26kB
+ *
+ * Rxpbsize: 0x20 (32kB)
+ * bmc2ossize: 0x02
+ * sumRx: 34kB
+ *
+ * See 8.3.1 && 8.3.2
+ */
+ val = (0x02 << 24 | 0x04 << 18 | 0x04 << 12 | 0x08 << 6 | 0x08);
+ wr32(E1000_ITPBS, val);
+ wr32(E1000_IRPBS, (0x02 << 6 | 0x20));
+
+ /* DMA Tx maximum packet size, the largest frame DMA should transport
+ * do not allow frames larger than 1522 + preample. Reg expects
+ * size in 64B increments. 802.1BA 6.3
+ * Round up to 1536 to handle 64B increments
+ *
+ * Initial value: 0x98 (152 => 9728 bytes)
+ */
+ wr32(E1000_DTXMXPKTSZ, 1536 >> 6);
+
+ /* Place card in Qav-mode, use tx-queue 0,1 for Qav
+ * (Credit-based shaper), 2,3 for standard priority (and
+ * best-effort) traffic.
+ *
+ * i210 8.12.19 and 8.12.21
+ *
+ * - Fetch: most empty and time based (not round-robin)
+ * - Transmit: Credit based shaper for SR queues
+ * - Data launch time valid (in Qav mode)
+ * - Wait for SR queues to ensure that launch time is always valid.
+ * - Set ~10us wait-time-delta, 32ns granularity
+ *
+ * Do *not* enable Tx for shaper (E1000_TQAVCTRL_DATA_TRAN_ARB)
+ * yet as we do not have data to Tx
+ */
+ val = E1000_TQAVCTRL_TXMODE |
+ E1000_TQAVCTRL_DATA_FETCH_ARB |
+ E1000_TQAVCTRL_DATA_TRAN_TIM |
+ E1000_TQAVCTRL_SP_WAIT_SR |
+ 320 << E1000_TQAVCTRL_FETCH_TM_SHIFT;
+
+ wr32(E1000_TQAVCTRL, val);
+
+ /* For now, only set CreditBased shaper for A and B, not set
+ * idleSlope as we have not yet gotten any streams.
+ * 8.12.19
+ */
+ wr32(E1000_TQAVCC(0), E1000_TQAVCC_QUEUEMODE);
+ wr32(E1000_TQAVCC(1), E1000_TQAVCC_QUEUEMODE);
+
+ wr32(E1000_TQAVHC(0), E1000_TQAVCH_ZERO_CREDIT);
+ wr32(E1000_TQAVHC(1), E1000_TQAVCH_ZERO_CREDIT);
+
+ /* reset Tx Descriptor tail and head for the queues */
+ wr32(E1000_TDT(0), 0);
+ wr32(E1000_TDT(1), 0);
+ wr32(E1000_TDH(0), 0);
+ wr32(E1000_TDH(1), 0);
+
+ _tsn_dump_regs(adapter);
+ dev_info(&adapter->pdev->dev, "\n");
+
+ adapter->sra_idleslope_res = 0;
+ adapter->srb_idleslope_res = 0;
+ adapter->tsn_ready = 1;
+
+ dev_info(&adapter->pdev->dev, "%s: setup done\n", __func__);
+}
+
+int igb_tsn_capable(struct net_device *netdev)
+{
+ struct igb_adapter *adapter;
+
+ if (!netdev)
+ return -EINVAL;
+ adapter = netdev_priv(netdev);
+ if (use_tsn == 1)
+ return adapter->tsn_ready == 1;
+ return 0;
+}
+
+/* igb_tsn_link_configure - configure NIC to handle a new stream
+ *
+ * @netdev: pointer to NIC device
+ * @class: the class for the stream used to find the correct queue.
+ * @framesize: size of each frame, *including* headers (not preamble)
+ * @vid: VLAN ID
+ *
+ * NOTE: the sr_class only instructs the driver which queue to use, not
+ * what priority the network expects for a given class. This is
+ * something userspace must find out and then let the tsn-driver set in
+ * the frame before xmit.
+ *
+ * FIXME: remove bw-req from a stream that goes away.
+ */
+int igb_tsn_link_configure(struct net_device *netdev, enum sr_class class,
+ u16 framesize, u16 vid)
+{
+ /* FIXME: push into adapter-storage */
+ static int class_a_size;
+ static int class_b_size;
+ int err;
+ u32 idle_slope_a = 0;
+ u32 idle_slope_b = 0;
+ u32 new_is = 0;
+ u32 hicred_a = 0;
+ u32 hicred_b = 0;
+ u32 tqavctrl;
+
+ struct igb_adapter *adapter;
+ struct e1000_hw *hw;
+
+ if (!netdev)
+ return -EINVAL;
+ adapter = netdev_priv(netdev);
+ hw = &adapter->hw;
+
+ if (!igb_tsn_capable(netdev)) {
+ pr_err("%s: NIC not capable\n", __func__);
+ return -EINVAL;
+ }
+
+ if (framesize > MAX_FRAME_SIZE || framesize < MIN_FRAME_SIZE) {
+ pr_err("%s: framesize (%u) must be [%d,%d]\n", __func__,
+ framesize, MIN_FRAME_SIZE, MAX_FRAME_SIZE);
+ return -EINVAL;
+ }
+
+ /* TODO: is this the correct place/way? Is it required? */
+ rtnl_lock();
+ pr_info("%s: adding VLAN %u to HW filter on device %s\n",
+ __func__, vid, netdev->name);
+ err = vlan_vid_add(netdev, htons(ETH_P_8021Q), vid);
+ if (err != 0)
+ pr_err("%s: error adding vlan %u, res=%d\n",
+ __func__, vid, err);
+ rtnl_unlock();
+
+ /* Grab current values of idle_slope */
+ idle_slope_a = rd32(E1000_TQAVHC(0)) & ~E1000_TQAVCH_ZERO_CREDIT;
+ idle_slope_b = rd32(E1000_TQAVHC(1)) & ~E1000_TQAVCH_ZERO_CREDIT;
+
+ /* Calculate new idle slope and add to appropriate idle_slope
+ * idle_slope = BW * linkrate * 2 (0r 0.2 for 100Mbit)
+ * BW: % of total bandwidth
+ */
+ new_is = framesize * E1000_LINK_RATE * 16 / 1000000;
+
+ switch (class) {
+ case SR_CLASS_A:
+ new_is *= 2; /* A is 8kHz, B is 4kHz */
+ idle_slope_a += new_is;
+ class_a_size = framesize;
+ break;
+ case SR_CLASS_B:
+ idle_slope_b += new_is;
+ class_b_size = framesize;
+ break;
+ default:
+ pr_err("%s: unhandled SR-class (%d)\n", __func__, class);
+ return -EINVAL;
+ }
+
+ /* HiCred: cred obtained while waiting for current frame &&
+ * higher-class frames to finish xmit.
+ *
+ * Covered in detail in 7.2.7.6 in i210 datasheet
+ * For class A: only worst-case framesize that just started;
+ * i.e. 1522 * idleSlope / linkrate;
+ * For class B: (worst-case framesize + burstSize(A))*idleSlope
+ *
+ * See 802.1Q Annex L, eq L.10 for hicred_a and L.41 for
+ * hicred_b
+ */
+ if (class == SR_CLASS_A) {
+ hicred_a = E1000_TQAVCH_ZERO_CREDIT + idle_slope_a * MAX_FRAME_SIZE / E1000_LINK_RATE;
+ wr32(E1000_TQAVCC(0), E1000_TQAVCC_QUEUEMODE | idle_slope_a);
+ wr32(E1000_TQAVHC(0), hicred_a);
+ } else {
+ hicred_b = E1000_TQAVCH_ZERO_CREDIT | idle_slope_b * (MAX_FRAME_SIZE + class_a_size) / (E1000_LINK_RATE - idle_slope_a);
+ wr32(E1000_TQAVCC(1), E1000_TQAVCC_QUEUEMODE | idle_slope_b);
+ wr32(E1000_TQAVHC(1), hicred_b);
+ }
+
+ /* Enable Tx for shaper now that we have data */
+ tqavctrl = rd32(E1000_TQAVCTRL);
+ if (!(tqavctrl & E1000_TQAVCTRL_DATA_TRAN_ARB)) {
+ tqavctrl |= E1000_TQAVCTRL_DATA_TRAN_ARB;
+ wr32(E1000_TQAVCTRL, tqavctrl);
+ }
+ _tsn_dump_regs(netdev_priv(netdev));
+ return 0;
+}
+
+#endif /* #if IS_ENABLED(CONFIG_IGB_TSN) */
--
2.7.4