ixgbe: this patch adds support for DCB to the kernel and ixgbe driver

This adds support for Data Center Bridging (DCB) features in the ixgbe
driver and adds an rtnetlink interface for configuring DCB to the
kernel.  The DCB feature support included are Priority Grouping (PG) -
which allows bandwidth guarantees to be allocated to groups to traffic
based on the 802.1q priority, and Priority Based Flow Control (PFC) -
which introduces a new MAC control PAUSE frame which works at
granularity of the 802.1p priority instead of the link (IEEE 802.3x).

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 398 insertions, 0 deletions

diff --git a/drivers/net/ixgbe/ixgbe_dcb_82598.c b/drivers/net/ixgbe/ixgbe_dcb_82598.c
new file mode 100644
index 00000000000..fce6867a451
--- /dev/null
+++ b/drivers/net/ixgbe/ixgbe_dcb_82598.c
@@ -0,0 +1,398 @@
+/*******************************************************************************
+
+  Intel 10 Gigabit PCI Express Linux driver
+  Copyright(c) 1999 - 2007 Intel Corporation.
+
+  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.
+
+  You should have received a copy of the GNU General Public License along with
+  this program; if not, write to the Free Software Foundation, Inc.,
+  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+
+  The full GNU General Public License is included in this distribution in
+  the file called "COPYING".
+
+  Contact Information:
+  Linux NICS <linux.nics@intel.com>
+  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
+  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+
+*******************************************************************************/
+
+#include "ixgbe.h"
+#include "ixgbe_type.h"
+#include "ixgbe_dcb.h"
+#include "ixgbe_dcb_82598.h"
+
+/**
+ * ixgbe_dcb_get_tc_stats_82598 - Return status data for each traffic class
+ * @hw: pointer to hardware structure
+ * @stats: pointer to statistics structure
+ * @tc_count:  Number of elements in bwg_array.
+ *
+ * This function returns the status data for each of the Traffic Classes in use.
+ */
+s32 ixgbe_dcb_get_tc_stats_82598(struct ixgbe_hw *hw,
+                                 struct ixgbe_hw_stats *stats,
+                                 u8 tc_count)
+{
+        int tc;
+
+        if (tc_count > MAX_TRAFFIC_CLASS)
+                return DCB_ERR_PARAM;
+
+        /* Statistics pertaining to each traffic class */
+        for (tc = 0; tc < tc_count; tc++) {
+                /* Transmitted Packets */
+                stats->qptc[tc] += IXGBE_READ_REG(hw, IXGBE_QPTC(tc));
+                /* Transmitted Bytes */
+                stats->qbtc[tc] += IXGBE_READ_REG(hw, IXGBE_QBTC(tc));
+                /* Received Packets */
+                stats->qprc[tc] += IXGBE_READ_REG(hw, IXGBE_QPRC(tc));
+                /* Received Bytes */
+                stats->qbrc[tc] += IXGBE_READ_REG(hw, IXGBE_QBRC(tc));
+        }
+
+        return 0;
+}
+
+/**
+ * ixgbe_dcb_get_pfc_stats_82598 - Returns CBFC status data
+ * @hw: pointer to hardware structure
+ * @stats: pointer to statistics structure
+ * @tc_count:  Number of elements in bwg_array.
+ *
+ * This function returns the CBFC status data for each of the Traffic Classes.
+ */
+s32 ixgbe_dcb_get_pfc_stats_82598(struct ixgbe_hw *hw,
+                                  struct ixgbe_hw_stats *stats,
+                                  u8 tc_count)
+{
+        int tc;
+
+        if (tc_count > MAX_TRAFFIC_CLASS)
+                return DCB_ERR_PARAM;
+
+        for (tc = 0; tc < tc_count; tc++) {
+                /* Priority XOFF Transmitted */
+                stats->pxofftxc[tc] += IXGBE_READ_REG(hw, IXGBE_PXOFFTXC(tc));
+                /* Priority XOFF Received */
+                stats->pxoffrxc[tc] += IXGBE_READ_REG(hw, IXGBE_PXOFFRXC(tc));
+        }
+
+        return 0;
+}
+
+/**
+ * ixgbe_dcb_config_packet_buffers_82598 - Configure packet buffers
+ * @hw: pointer to hardware structure
+ * @dcb_config: pointer to ixgbe_dcb_config structure
+ *
+ * Configure packet buffers for DCB mode.
+ */
+s32 ixgbe_dcb_config_packet_buffers_82598(struct ixgbe_hw *hw,
+                                          struct ixgbe_dcb_config *dcb_config)
+{
+        s32 ret_val = 0;
+        u32 value = IXGBE_RXPBSIZE_64KB;
+        u8  i = 0;
+
+        /* Setup Rx packet buffer sizes */
+        switch (dcb_config->rx_pba_cfg) {
+        case pba_80_48:
+                /* Setup the first four at 80KB */
+                value = IXGBE_RXPBSIZE_80KB;
+                for (; i < 4; i++)
+                        IXGBE_WRITE_REG(hw, IXGBE_RXPBSIZE(i), value);
+                /* Setup the last four at 48KB...don't re-init i */
+                value = IXGBE_RXPBSIZE_48KB;
+                /* Fall Through */
+        case pba_equal:
+        default:
+                for (; i < IXGBE_MAX_PACKET_BUFFERS; i++)
+                        IXGBE_WRITE_REG(hw, IXGBE_RXPBSIZE(i), value);
+
+                /* Setup Tx packet buffer sizes */
+                for (i = 0; i < IXGBE_MAX_PACKET_BUFFERS; i++) {
+                        IXGBE_WRITE_REG(hw, IXGBE_TXPBSIZE(i),
+                                        IXGBE_TXPBSIZE_40KB);
+                }
+                break;
+        }
+
+        return ret_val;
+}
+
+/**
+ * ixgbe_dcb_config_rx_arbiter_82598 - Config Rx data arbiter
+ * @hw: pointer to hardware structure
+ * @dcb_config: pointer to ixgbe_dcb_config structure
+ *
+ * Configure Rx Data Arbiter and credits for each traffic class.
+ */
+s32 ixgbe_dcb_config_rx_arbiter_82598(struct ixgbe_hw *hw,
+                                      struct ixgbe_dcb_config *dcb_config)
+{
+        struct tc_bw_alloc    *p;
+        u32    reg           = 0;
+        u32    credit_refill = 0;
+        u32    credit_max    = 0;
+        u8     i             = 0;
+
+        reg = IXGBE_READ_REG(hw, IXGBE_RUPPBMR) | IXGBE_RUPPBMR_MQA;
+        IXGBE_WRITE_REG(hw, IXGBE_RUPPBMR, reg);
+
+        reg = IXGBE_READ_REG(hw, IXGBE_RMCS);
+        /* Enable Arbiter */
+        reg &= ~IXGBE_RMCS_ARBDIS;
+        /* Enable Receive Recycle within the BWG */
+        reg |= IXGBE_RMCS_RRM;
+        /* Enable Deficit Fixed Priority arbitration*/
+        reg |= IXGBE_RMCS_DFP;
+
+        IXGBE_WRITE_REG(hw, IXGBE_RMCS, reg);
+
+        /* Configure traffic class credits and priority */
+        for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
+                p = &dcb_config->tc_config[i].path[DCB_RX_CONFIG];
+                credit_refill = p->data_credits_refill;
+                credit_max    = p->data_credits_max;
+
+                reg = credit_refill | (credit_max << IXGBE_RT2CR_MCL_SHIFT);
+
+                if (p->prio_type == prio_link)
+                        reg |= IXGBE_RT2CR_LSP;
+
+                IXGBE_WRITE_REG(hw, IXGBE_RT2CR(i), reg);
+        }
+
+        reg = IXGBE_READ_REG(hw, IXGBE_RDRXCTL);
+        reg |= IXGBE_RDRXCTL_RDMTS_1_2;
+        reg |= IXGBE_RDRXCTL_MPBEN;
+        reg |= IXGBE_RDRXCTL_MCEN;
+        IXGBE_WRITE_REG(hw, IXGBE_RDRXCTL, reg);
+
+        reg = IXGBE_READ_REG(hw, IXGBE_RXCTRL);
+        /* Make sure there is enough descriptors before arbitration */
+        reg &= ~IXGBE_RXCTRL_DMBYPS;
+        IXGBE_WRITE_REG(hw, IXGBE_RXCTRL, reg);
+
+        return 0;
+}
+
+/**
+ * ixgbe_dcb_config_tx_desc_arbiter_82598 - Config Tx Desc. arbiter
+ * @hw: pointer to hardware structure
+ * @dcb_config: pointer to ixgbe_dcb_config structure
+ *
+ * Configure Tx Descriptor Arbiter and credits for each traffic class.
+ */
+s32 ixgbe_dcb_config_tx_desc_arbiter_82598(struct ixgbe_hw *hw,
+                                           struct ixgbe_dcb_config *dcb_config)
+{
+        struct tc_bw_alloc *p;
+        u32    reg, max_credits;
+        u8     i;
+
+        reg = IXGBE_READ_REG(hw, IXGBE_DPMCS);
+
+        /* Enable arbiter */
+        reg &= ~IXGBE_DPMCS_ARBDIS;
+        if (!(dcb_config->round_robin_enable)) {
+                /* Enable DFP and Recycle mode */
+                reg |= (IXGBE_DPMCS_TDPAC | IXGBE_DPMCS_TRM);
+        }
+        reg |= IXGBE_DPMCS_TSOEF;
+        /* Configure Max TSO packet size 34KB including payload and headers */
+        reg |= (0x4 << IXGBE_DPMCS_MTSOS_SHIFT);
+
+        IXGBE_WRITE_REG(hw, IXGBE_DPMCS, reg);
+
+        /* Configure traffic class credits and priority */
+        for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
+                p = &dcb_config->tc_config[i].path[DCB_TX_CONFIG];
+                max_credits = dcb_config->tc_config[i].desc_credits_max;
+                reg = max_credits << IXGBE_TDTQ2TCCR_MCL_SHIFT;
+                reg |= p->data_credits_refill;
+                reg |= (u32)(p->bwg_id) << IXGBE_TDTQ2TCCR_BWG_SHIFT;
+
+                if (p->prio_type == prio_group)
+                        reg |= IXGBE_TDTQ2TCCR_GSP;
+
+                if (p->prio_type == prio_link)
+                        reg |= IXGBE_TDTQ2TCCR_LSP;
+
+                IXGBE_WRITE_REG(hw, IXGBE_TDTQ2TCCR(i), reg);
+        }
+
+        return 0;
+}
+
+/**
+ * ixgbe_dcb_config_tx_data_arbiter_82598 - Config Tx data arbiter
+ * @hw: pointer to hardware structure
+ * @dcb_config: pointer to ixgbe_dcb_config structure
+ *
+ * Configure Tx Data Arbiter and credits for each traffic class.
+ */
+s32 ixgbe_dcb_config_tx_data_arbiter_82598(struct ixgbe_hw *hw,
+                                           struct ixgbe_dcb_config *dcb_config)
+{
+        struct tc_bw_alloc *p;
+        u32 reg;
+        u8 i;
+
+        reg = IXGBE_READ_REG(hw, IXGBE_PDPMCS);
+        /* Enable Data Plane Arbiter */
+        reg &= ~IXGBE_PDPMCS_ARBDIS;
+        /* Enable DFP and Transmit Recycle Mode */
+        reg |= (IXGBE_PDPMCS_TPPAC | IXGBE_PDPMCS_TRM);
+
+        IXGBE_WRITE_REG(hw, IXGBE_PDPMCS, reg);
+
+        /* Configure traffic class credits and priority */
+        for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
+                p = &dcb_config->tc_config[i].path[DCB_TX_CONFIG];
+                reg = p->data_credits_refill;
+                reg |= (u32)(p->data_credits_max) << IXGBE_TDPT2TCCR_MCL_SHIFT;
+                reg |= (u32)(p->bwg_id) << IXGBE_TDPT2TCCR_BWG_SHIFT;
+
+                if (p->prio_type == prio_group)
+                        reg |= IXGBE_TDPT2TCCR_GSP;
+
+                if (p->prio_type == prio_link)
+                        reg |= IXGBE_TDPT2TCCR_LSP;
+
+                IXGBE_WRITE_REG(hw, IXGBE_TDPT2TCCR(i), reg);
+        }
+
+        /* Enable Tx packet buffer division */
+        reg = IXGBE_READ_REG(hw, IXGBE_DTXCTL);
+        reg |= IXGBE_DTXCTL_ENDBUBD;
+        IXGBE_WRITE_REG(hw, IXGBE_DTXCTL, reg);
+
+        return 0;
+}
+
+/**
+ * ixgbe_dcb_config_pfc_82598 - Config priority flow control
+ * @hw: pointer to hardware structure
+ * @dcb_config: pointer to ixgbe_dcb_config structure
+ *
+ * Configure Priority Flow Control for each traffic class.
+ */
+s32 ixgbe_dcb_config_pfc_82598(struct ixgbe_hw *hw,
+                               struct ixgbe_dcb_config *dcb_config)
+{
+        u32 reg, rx_pba_size;
+        u8  i;
+
+        /* Enable Transmit Priority Flow Control */
+        reg = IXGBE_READ_REG(hw, IXGBE_RMCS);
+        reg &= ~IXGBE_RMCS_TFCE_802_3X;
+        /* correct the reporting of our flow control status */
+        hw->fc.type = ixgbe_fc_none;
+        reg |= IXGBE_RMCS_TFCE_PRIORITY;
+        IXGBE_WRITE_REG(hw, IXGBE_RMCS, reg);
+
+        /* Enable Receive Priority Flow Control */
+        reg = IXGBE_READ_REG(hw, IXGBE_FCTRL);
+        reg &= ~IXGBE_FCTRL_RFCE;
+        reg |= IXGBE_FCTRL_RPFCE;
+        IXGBE_WRITE_REG(hw, IXGBE_FCTRL, reg);
+
+        /*
+         * Configure flow control thresholds and enable priority flow control
+         * for each traffic class.
+         */
+        for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
+                if (dcb_config->rx_pba_cfg == pba_equal) {
+                        rx_pba_size = IXGBE_RXPBSIZE_64KB;
+                } else {
+                        rx_pba_size = (i < 4) ? IXGBE_RXPBSIZE_80KB
+                                              : IXGBE_RXPBSIZE_48KB;
+                }
+
+                reg = ((rx_pba_size >> 5) &  0xFFF0);
+                if (dcb_config->tc_config[i].dcb_pfc == pfc_enabled_tx ||
+                    dcb_config->tc_config[i].dcb_pfc == pfc_enabled_full)
+                        reg |= IXGBE_FCRTL_XONE;
+
+                IXGBE_WRITE_REG(hw, IXGBE_FCRTL(i), reg);
+
+                reg = ((rx_pba_size >> 2) & 0xFFF0);
+                if (dcb_config->tc_config[i].dcb_pfc == pfc_enabled_tx ||
+                    dcb_config->tc_config[i].dcb_pfc == pfc_enabled_full)
+                        reg |= IXGBE_FCRTH_FCEN;
+
+                IXGBE_WRITE_REG(hw, IXGBE_FCRTH(i), reg);
+        }
+
+        /* Configure pause time */
+        for (i = 0; i < (MAX_TRAFFIC_CLASS >> 1); i++)
+                IXGBE_WRITE_REG(hw, IXGBE_FCTTV(i), 0x68006800);
+
+        /* Configure flow control refresh threshold value */
+        IXGBE_WRITE_REG(hw, IXGBE_FCRTV, 0x3400);
+
+        return 0;
+}
+
+/**
+ * ixgbe_dcb_config_tc_stats_82598 - Configure traffic class statistics
+ * @hw: pointer to hardware structure
+ *
+ * Configure queue statistics registers, all queues belonging to same traffic
+ * class uses a single set of queue statistics counters.
+ */
+s32 ixgbe_dcb_config_tc_stats_82598(struct ixgbe_hw *hw)
+{
+        u32 reg = 0;
+        u8  i   = 0;
+        u8  j   = 0;
+
+        /* Receive Queues stats setting -  8 queues per statistics reg */
+        for (i = 0, j = 0; i < 15 && j < 8; i = i + 2, j++) {
+                reg = IXGBE_READ_REG(hw, IXGBE_RQSMR(i));
+                reg |= ((0x1010101) * j);
+                IXGBE_WRITE_REG(hw, IXGBE_RQSMR(i), reg);
+                reg = IXGBE_READ_REG(hw, IXGBE_RQSMR(i + 1));
+                reg |= ((0x1010101) * j);
+                IXGBE_WRITE_REG(hw, IXGBE_RQSMR(i + 1), reg);
+        }
+        /* Transmit Queues stats setting -  4 queues per statistics reg */
+        for (i = 0; i < 8; i++) {
+                reg = IXGBE_READ_REG(hw, IXGBE_TQSMR(i));
+                reg |= ((0x1010101) * i);
+                IXGBE_WRITE_REG(hw, IXGBE_TQSMR(i), reg);
+        }
+
+        return 0;
+}
+
+/**
+ * ixgbe_dcb_hw_config_82598 - Config and enable DCB
+ * @hw: pointer to hardware structure
+ * @dcb_config: pointer to ixgbe_dcb_config structure
+ *
+ * Configure dcb settings and enable dcb mode.
+ */
+s32 ixgbe_dcb_hw_config_82598(struct ixgbe_hw *hw,
+                              struct ixgbe_dcb_config *dcb_config)
+{
+        ixgbe_dcb_config_packet_buffers_82598(hw, dcb_config);
+        ixgbe_dcb_config_rx_arbiter_82598(hw, dcb_config);
+        ixgbe_dcb_config_tx_desc_arbiter_82598(hw, dcb_config);
+        ixgbe_dcb_config_tx_data_arbiter_82598(hw, dcb_config);
+        ixgbe_dcb_config_pfc_82598(hw, dcb_config);
+        ixgbe_dcb_config_tc_stats_82598(hw);
+
+        return 0;
+}