Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / ntb / ntb_hw.c
diff --git a/kernel/drivers/ntb/ntb_hw.c b/kernel/drivers/ntb/ntb_hw.c
new file mode 100644 (file)
index 0000000..15f9b7c
--- /dev/null
@@ -0,0 +1,1897 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ *   redistributing this file, you may do so under either license.
+ *
+ *   GPL LICENSE SUMMARY
+ *
+ *   Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of version 2 of the GNU General Public License as
+ *   published by the Free Software Foundation.
+ *
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copy
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Intel PCIe NTB Linux driver
+ *
+ * Contact Information:
+ * Jon Mason <jon.mason@intel.com>
+ */
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include "ntb_hw.h"
+#include "ntb_regs.h"
+
+#define NTB_NAME       "Intel(R) PCI-E Non-Transparent Bridge Driver"
+#define NTB_VER                "1.0"
+
+MODULE_DESCRIPTION(NTB_NAME);
+MODULE_VERSION(NTB_VER);
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Intel Corporation");
+
+enum {
+       NTB_CONN_TRANSPARENT = 0,
+       NTB_CONN_B2B,
+       NTB_CONN_RP,
+};
+
+enum {
+       NTB_DEV_USD = 0,
+       NTB_DEV_DSD,
+};
+
+enum {
+       SNB_HW = 0,
+       BWD_HW,
+};
+
+static struct dentry *debugfs_dir;
+
+#define BWD_LINK_RECOVERY_TIME 500
+
+/* Translate memory window 0,1,2 to BAR 2,4,5 */
+#define MW_TO_BAR(mw)  (mw == 0 ? 2 : (mw == 1 ? 4 : 5))
+
+static const struct pci_device_id ntb_pci_tbl[] = {
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_BWD)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_JSF)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_SNB)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_IVT)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_HSX)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_JSF)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_SNB)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_IVT)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_HSX)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_JSF)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_SNB)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_IVT)},
+       {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_HSX)},
+       {0}
+};
+MODULE_DEVICE_TABLE(pci, ntb_pci_tbl);
+
+static int is_ntb_xeon(struct ntb_device *ndev)
+{
+       switch (ndev->pdev->device) {
+       case PCI_DEVICE_ID_INTEL_NTB_SS_JSF:
+       case PCI_DEVICE_ID_INTEL_NTB_SS_SNB:
+       case PCI_DEVICE_ID_INTEL_NTB_SS_IVT:
+       case PCI_DEVICE_ID_INTEL_NTB_SS_HSX:
+       case PCI_DEVICE_ID_INTEL_NTB_PS_JSF:
+       case PCI_DEVICE_ID_INTEL_NTB_PS_SNB:
+       case PCI_DEVICE_ID_INTEL_NTB_PS_IVT:
+       case PCI_DEVICE_ID_INTEL_NTB_PS_HSX:
+       case PCI_DEVICE_ID_INTEL_NTB_B2B_JSF:
+       case PCI_DEVICE_ID_INTEL_NTB_B2B_SNB:
+       case PCI_DEVICE_ID_INTEL_NTB_B2B_IVT:
+       case PCI_DEVICE_ID_INTEL_NTB_B2B_HSX:
+               return 1;
+       default:
+               return 0;
+       }
+
+       return 0;
+}
+
+static int is_ntb_atom(struct ntb_device *ndev)
+{
+       switch (ndev->pdev->device) {
+       case PCI_DEVICE_ID_INTEL_NTB_B2B_BWD:
+               return 1;
+       default:
+               return 0;
+       }
+
+       return 0;
+}
+
+static void ntb_set_errata_flags(struct ntb_device *ndev)
+{
+       switch (ndev->pdev->device) {
+       /*
+        * this workaround applies to all platform up to IvyBridge
+        * Haswell has splitbar support and use a different workaround
+        */
+       case PCI_DEVICE_ID_INTEL_NTB_SS_JSF:
+       case PCI_DEVICE_ID_INTEL_NTB_SS_SNB:
+       case PCI_DEVICE_ID_INTEL_NTB_SS_IVT:
+       case PCI_DEVICE_ID_INTEL_NTB_SS_HSX:
+       case PCI_DEVICE_ID_INTEL_NTB_PS_JSF:
+       case PCI_DEVICE_ID_INTEL_NTB_PS_SNB:
+       case PCI_DEVICE_ID_INTEL_NTB_PS_IVT:
+       case PCI_DEVICE_ID_INTEL_NTB_PS_HSX:
+       case PCI_DEVICE_ID_INTEL_NTB_B2B_JSF:
+       case PCI_DEVICE_ID_INTEL_NTB_B2B_SNB:
+       case PCI_DEVICE_ID_INTEL_NTB_B2B_IVT:
+       case PCI_DEVICE_ID_INTEL_NTB_B2B_HSX:
+               ndev->wa_flags |= WA_SNB_ERR;
+               break;
+       }
+}
+
+/**
+ * ntb_register_event_callback() - register event callback
+ * @ndev: pointer to ntb_device instance
+ * @func: callback function to register
+ *
+ * This function registers a callback for any HW driver events such as link
+ * up/down, power management notices and etc.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_register_event_callback(struct ntb_device *ndev,
+                               void (*func)(void *handle,
+                                            enum ntb_hw_event event))
+{
+       if (ndev->event_cb)
+               return -EINVAL;
+
+       ndev->event_cb = func;
+
+       return 0;
+}
+
+/**
+ * ntb_unregister_event_callback() - unregisters the event callback
+ * @ndev: pointer to ntb_device instance
+ *
+ * This function unregisters the existing callback from transport
+ */
+void ntb_unregister_event_callback(struct ntb_device *ndev)
+{
+       ndev->event_cb = NULL;
+}
+
+static void ntb_irq_work(unsigned long data)
+{
+       struct ntb_db_cb *db_cb = (struct ntb_db_cb *)data;
+       int rc;
+
+       rc = db_cb->callback(db_cb->data, db_cb->db_num);
+       if (rc)
+               tasklet_schedule(&db_cb->irq_work);
+       else {
+               struct ntb_device *ndev = db_cb->ndev;
+               unsigned long mask;
+
+               mask = readw(ndev->reg_ofs.ldb_mask);
+               clear_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+               writew(mask, ndev->reg_ofs.ldb_mask);
+       }
+}
+
+/**
+ * ntb_register_db_callback() - register a callback for doorbell interrupt
+ * @ndev: pointer to ntb_device instance
+ * @idx: doorbell index to register callback, zero based
+ * @data: pointer to be returned to caller with every callback
+ * @func: callback function to register
+ *
+ * This function registers a callback function for the doorbell interrupt
+ * on the primary side. The function will unmask the doorbell as well to
+ * allow interrupt.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx,
+                            void *data, int (*func)(void *data, int db_num))
+{
+       unsigned long mask;
+
+       if (idx >= ndev->max_cbs || ndev->db_cb[idx].callback) {
+               dev_warn(&ndev->pdev->dev, "Invalid Index.\n");
+               return -EINVAL;
+       }
+
+       ndev->db_cb[idx].callback = func;
+       ndev->db_cb[idx].data = data;
+       ndev->db_cb[idx].ndev = ndev;
+
+       tasklet_init(&ndev->db_cb[idx].irq_work, ntb_irq_work,
+                    (unsigned long) &ndev->db_cb[idx]);
+
+       /* unmask interrupt */
+       mask = readw(ndev->reg_ofs.ldb_mask);
+       clear_bit(idx * ndev->bits_per_vector, &mask);
+       writew(mask, ndev->reg_ofs.ldb_mask);
+
+       return 0;
+}
+
+/**
+ * ntb_unregister_db_callback() - unregister a callback for doorbell interrupt
+ * @ndev: pointer to ntb_device instance
+ * @idx: doorbell index to register callback, zero based
+ *
+ * This function unregisters a callback function for the doorbell interrupt
+ * on the primary side. The function will also mask the said doorbell.
+ */
+void ntb_unregister_db_callback(struct ntb_device *ndev, unsigned int idx)
+{
+       unsigned long mask;
+
+       if (idx >= ndev->max_cbs || !ndev->db_cb[idx].callback)
+               return;
+
+       mask = readw(ndev->reg_ofs.ldb_mask);
+       set_bit(idx * ndev->bits_per_vector, &mask);
+       writew(mask, ndev->reg_ofs.ldb_mask);
+
+       tasklet_disable(&ndev->db_cb[idx].irq_work);
+
+       ndev->db_cb[idx].callback = NULL;
+}
+
+/**
+ * ntb_find_transport() - find the transport pointer
+ * @transport: pointer to pci device
+ *
+ * Given the pci device pointer, return the transport pointer passed in when
+ * the transport attached when it was inited.
+ *
+ * RETURNS: pointer to transport.
+ */
+void *ntb_find_transport(struct pci_dev *pdev)
+{
+       struct ntb_device *ndev = pci_get_drvdata(pdev);
+       return ndev->ntb_transport;
+}
+
+/**
+ * ntb_register_transport() - Register NTB transport with NTB HW driver
+ * @transport: transport identifier
+ *
+ * This function allows a transport to reserve the hardware driver for
+ * NTB usage.
+ *
+ * RETURNS: pointer to ntb_device, NULL on error.
+ */
+struct ntb_device *ntb_register_transport(struct pci_dev *pdev, void *transport)
+{
+       struct ntb_device *ndev = pci_get_drvdata(pdev);
+
+       if (ndev->ntb_transport)
+               return NULL;
+
+       ndev->ntb_transport = transport;
+       return ndev;
+}
+
+/**
+ * ntb_unregister_transport() - Unregister the transport with the NTB HW driver
+ * @ndev - ntb_device of the transport to be freed
+ *
+ * This function unregisters the transport from the HW driver and performs any
+ * necessary cleanups.
+ */
+void ntb_unregister_transport(struct ntb_device *ndev)
+{
+       int i;
+
+       if (!ndev->ntb_transport)
+               return;
+
+       for (i = 0; i < ndev->max_cbs; i++)
+               ntb_unregister_db_callback(ndev, i);
+
+       ntb_unregister_event_callback(ndev);
+       ndev->ntb_transport = NULL;
+}
+
+/**
+ * ntb_write_local_spad() - write to the secondary scratchpad register
+ * @ndev: pointer to ntb_device instance
+ * @idx: index to the scratchpad register, 0 based
+ * @val: the data value to put into the register
+ *
+ * This function allows writing of a 32bit value to the indexed scratchpad
+ * register. This writes over the data mirrored to the local scratchpad register
+ * by the remote system.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_write_local_spad(struct ntb_device *ndev, unsigned int idx, u32 val)
+{
+       if (idx >= ndev->limits.max_spads)
+               return -EINVAL;
+
+       dev_dbg(&ndev->pdev->dev, "Writing %x to local scratch pad index %d\n",
+               val, idx);
+       writel(val, ndev->reg_ofs.spad_read + idx * 4);
+
+       return 0;
+}
+
+/**
+ * ntb_read_local_spad() - read from the primary scratchpad register
+ * @ndev: pointer to ntb_device instance
+ * @idx: index to scratchpad register, 0 based
+ * @val: pointer to 32bit integer for storing the register value
+ *
+ * This function allows reading of the 32bit scratchpad register on
+ * the primary (internal) side.  This allows the local system to read data
+ * written and mirrored to the scratchpad register by the remote system.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_read_local_spad(struct ntb_device *ndev, unsigned int idx, u32 *val)
+{
+       if (idx >= ndev->limits.max_spads)
+               return -EINVAL;
+
+       *val = readl(ndev->reg_ofs.spad_write + idx * 4);
+       dev_dbg(&ndev->pdev->dev,
+               "Reading %x from local scratch pad index %d\n", *val, idx);
+
+       return 0;
+}
+
+/**
+ * ntb_write_remote_spad() - write to the secondary scratchpad register
+ * @ndev: pointer to ntb_device instance
+ * @idx: index to the scratchpad register, 0 based
+ * @val: the data value to put into the register
+ *
+ * This function allows writing of a 32bit value to the indexed scratchpad
+ * register. The register resides on the secondary (external) side.  This allows
+ * the local system to write data to be mirrored to the remote systems
+ * scratchpad register.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_write_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 val)
+{
+       if (idx >= ndev->limits.max_spads)
+               return -EINVAL;
+
+       dev_dbg(&ndev->pdev->dev, "Writing %x to remote scratch pad index %d\n",
+               val, idx);
+       writel(val, ndev->reg_ofs.spad_write + idx * 4);
+
+       return 0;
+}
+
+/**
+ * ntb_read_remote_spad() - read from the primary scratchpad register
+ * @ndev: pointer to ntb_device instance
+ * @idx: index to scratchpad register, 0 based
+ * @val: pointer to 32bit integer for storing the register value
+ *
+ * This function allows reading of the 32bit scratchpad register on
+ * the primary (internal) side.  This alloows the local system to read the data
+ * it wrote to be mirrored on the remote system.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_read_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 *val)
+{
+       if (idx >= ndev->limits.max_spads)
+               return -EINVAL;
+
+       *val = readl(ndev->reg_ofs.spad_read + idx * 4);
+       dev_dbg(&ndev->pdev->dev,
+               "Reading %x from remote scratch pad index %d\n", *val, idx);
+
+       return 0;
+}
+
+/**
+ * ntb_get_mw_base() - get addr for the NTB memory window
+ * @ndev: pointer to ntb_device instance
+ * @mw: memory window number
+ *
+ * This function provides the base address of the memory window specified.
+ *
+ * RETURNS: address, or NULL on error.
+ */
+resource_size_t ntb_get_mw_base(struct ntb_device *ndev, unsigned int mw)
+{
+       if (mw >= ntb_max_mw(ndev))
+               return 0;
+
+       return pci_resource_start(ndev->pdev, MW_TO_BAR(mw));
+}
+
+/**
+ * ntb_get_mw_vbase() - get virtual addr for the NTB memory window
+ * @ndev: pointer to ntb_device instance
+ * @mw: memory window number
+ *
+ * This function provides the base virtual address of the memory window
+ * specified.
+ *
+ * RETURNS: pointer to virtual address, or NULL on error.
+ */
+void __iomem *ntb_get_mw_vbase(struct ntb_device *ndev, unsigned int mw)
+{
+       if (mw >= ntb_max_mw(ndev))
+               return NULL;
+
+       return ndev->mw[mw].vbase;
+}
+
+/**
+ * ntb_get_mw_size() - return size of NTB memory window
+ * @ndev: pointer to ntb_device instance
+ * @mw: memory window number
+ *
+ * This function provides the physical size of the memory window specified
+ *
+ * RETURNS: the size of the memory window or zero on error
+ */
+u64 ntb_get_mw_size(struct ntb_device *ndev, unsigned int mw)
+{
+       if (mw >= ntb_max_mw(ndev))
+               return 0;
+
+       return ndev->mw[mw].bar_sz;
+}
+
+/**
+ * ntb_set_mw_addr - set the memory window address
+ * @ndev: pointer to ntb_device instance
+ * @mw: memory window number
+ * @addr: base address for data
+ *
+ * This function sets the base physical address of the memory window.  This
+ * memory address is where data from the remote system will be transfered into
+ * or out of depending on how the transport is configured.
+ */
+void ntb_set_mw_addr(struct ntb_device *ndev, unsigned int mw, u64 addr)
+{
+       if (mw >= ntb_max_mw(ndev))
+               return;
+
+       dev_dbg(&ndev->pdev->dev, "Writing addr %Lx to BAR %d\n", addr,
+               MW_TO_BAR(mw));
+
+       ndev->mw[mw].phys_addr = addr;
+
+       switch (MW_TO_BAR(mw)) {
+       case NTB_BAR_23:
+               writeq(addr, ndev->reg_ofs.bar2_xlat);
+               break;
+       case NTB_BAR_4:
+               if (ndev->split_bar)
+                       writel(addr, ndev->reg_ofs.bar4_xlat);
+               else
+                       writeq(addr, ndev->reg_ofs.bar4_xlat);
+               break;
+       case NTB_BAR_5:
+               writel(addr, ndev->reg_ofs.bar5_xlat);
+               break;
+       }
+}
+
+/**
+ * ntb_ring_doorbell() - Set the doorbell on the secondary/external side
+ * @ndev: pointer to ntb_device instance
+ * @db: doorbell to ring
+ *
+ * This function allows triggering of a doorbell on the secondary/external
+ * side that will initiate an interrupt on the remote host
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+void ntb_ring_doorbell(struct ntb_device *ndev, unsigned int db)
+{
+       dev_dbg(&ndev->pdev->dev, "%s: ringing doorbell %d\n", __func__, db);
+
+       if (ndev->hw_type == BWD_HW)
+               writeq((u64) 1 << db, ndev->reg_ofs.rdb);
+       else
+               writew(((1 << ndev->bits_per_vector) - 1) <<
+                      (db * ndev->bits_per_vector), ndev->reg_ofs.rdb);
+}
+
+static void bwd_recover_link(struct ntb_device *ndev)
+{
+       u32 status;
+
+       /* Driver resets the NTB ModPhy lanes - magic! */
+       writeb(0xe0, ndev->reg_base + BWD_MODPHY_PCSREG6);
+       writeb(0x40, ndev->reg_base + BWD_MODPHY_PCSREG4);
+       writeb(0x60, ndev->reg_base + BWD_MODPHY_PCSREG4);
+       writeb(0x60, ndev->reg_base + BWD_MODPHY_PCSREG6);
+
+       /* Driver waits 100ms to allow the NTB ModPhy to settle */
+       msleep(100);
+
+       /* Clear AER Errors, write to clear */
+       status = readl(ndev->reg_base + BWD_ERRCORSTS_OFFSET);
+       dev_dbg(&ndev->pdev->dev, "ERRCORSTS = %x\n", status);
+       status &= PCI_ERR_COR_REP_ROLL;
+       writel(status, ndev->reg_base + BWD_ERRCORSTS_OFFSET);
+
+       /* Clear unexpected electrical idle event in LTSSM, write to clear */
+       status = readl(ndev->reg_base + BWD_LTSSMERRSTS0_OFFSET);
+       dev_dbg(&ndev->pdev->dev, "LTSSMERRSTS0 = %x\n", status);
+       status |= BWD_LTSSMERRSTS0_UNEXPECTEDEI;
+       writel(status, ndev->reg_base + BWD_LTSSMERRSTS0_OFFSET);
+
+       /* Clear DeSkew Buffer error, write to clear */
+       status = readl(ndev->reg_base + BWD_DESKEWSTS_OFFSET);
+       dev_dbg(&ndev->pdev->dev, "DESKEWSTS = %x\n", status);
+       status |= BWD_DESKEWSTS_DBERR;
+       writel(status, ndev->reg_base + BWD_DESKEWSTS_OFFSET);
+
+       status = readl(ndev->reg_base + BWD_IBSTERRRCRVSTS0_OFFSET);
+       dev_dbg(&ndev->pdev->dev, "IBSTERRRCRVSTS0 = %x\n", status);
+       status &= BWD_IBIST_ERR_OFLOW;
+       writel(status, ndev->reg_base + BWD_IBSTERRRCRVSTS0_OFFSET);
+
+       /* Releases the NTB state machine to allow the link to retrain */
+       status = readl(ndev->reg_base + BWD_LTSSMSTATEJMP_OFFSET);
+       dev_dbg(&ndev->pdev->dev, "LTSSMSTATEJMP = %x\n", status);
+       status &= ~BWD_LTSSMSTATEJMP_FORCEDETECT;
+       writel(status, ndev->reg_base + BWD_LTSSMSTATEJMP_OFFSET);
+}
+
+static void ntb_link_event(struct ntb_device *ndev, int link_state)
+{
+       unsigned int event;
+
+       if (ndev->link_status == link_state)
+               return;
+
+       if (link_state == NTB_LINK_UP) {
+               u16 status;
+
+               dev_info(&ndev->pdev->dev, "Link Up\n");
+               ndev->link_status = NTB_LINK_UP;
+               event = NTB_EVENT_HW_LINK_UP;
+
+               if (is_ntb_atom(ndev) ||
+                   ndev->conn_type == NTB_CONN_TRANSPARENT)
+                       status = readw(ndev->reg_ofs.lnk_stat);
+               else {
+                       int rc = pci_read_config_word(ndev->pdev,
+                                                     SNB_LINK_STATUS_OFFSET,
+                                                     &status);
+                       if (rc)
+                               return;
+               }
+
+               ndev->link_width = (status & NTB_LINK_WIDTH_MASK) >> 4;
+               ndev->link_speed = (status & NTB_LINK_SPEED_MASK);
+               dev_info(&ndev->pdev->dev, "Link Width %d, Link Speed %d\n",
+                        ndev->link_width, ndev->link_speed);
+       } else {
+               dev_info(&ndev->pdev->dev, "Link Down\n");
+               ndev->link_status = NTB_LINK_DOWN;
+               event = NTB_EVENT_HW_LINK_DOWN;
+               /* Don't modify link width/speed, we need it in link recovery */
+       }
+
+       /* notify the upper layer if we have an event change */
+       if (ndev->event_cb)
+               ndev->event_cb(ndev->ntb_transport, event);
+}
+
+static int ntb_link_status(struct ntb_device *ndev)
+{
+       int link_state;
+
+       if (is_ntb_atom(ndev)) {
+               u32 ntb_cntl;
+
+               ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+               if (ntb_cntl & BWD_CNTL_LINK_DOWN)
+                       link_state = NTB_LINK_DOWN;
+               else
+                       link_state = NTB_LINK_UP;
+       } else {
+               u16 status;
+               int rc;
+
+               rc = pci_read_config_word(ndev->pdev, SNB_LINK_STATUS_OFFSET,
+                                         &status);
+               if (rc)
+                       return rc;
+
+               if (status & NTB_LINK_STATUS_ACTIVE)
+                       link_state = NTB_LINK_UP;
+               else
+                       link_state = NTB_LINK_DOWN;
+       }
+
+       ntb_link_event(ndev, link_state);
+
+       return 0;
+}
+
+static void bwd_link_recovery(struct work_struct *work)
+{
+       struct ntb_device *ndev = container_of(work, struct ntb_device,
+                                              lr_timer.work);
+       u32 status32;
+
+       bwd_recover_link(ndev);
+       /* There is a potential race between the 2 NTB devices recovering at the
+        * same time.  If the times are the same, the link will not recover and
+        * the driver will be stuck in this loop forever.  Add a random interval
+        * to the recovery time to prevent this race.
+        */
+       msleep(BWD_LINK_RECOVERY_TIME + prandom_u32() % BWD_LINK_RECOVERY_TIME);
+
+       status32 = readl(ndev->reg_base + BWD_LTSSMSTATEJMP_OFFSET);
+       if (status32 & BWD_LTSSMSTATEJMP_FORCEDETECT)
+               goto retry;
+
+       status32 = readl(ndev->reg_base + BWD_IBSTERRRCRVSTS0_OFFSET);
+       if (status32 & BWD_IBIST_ERR_OFLOW)
+               goto retry;
+
+       status32 = readl(ndev->reg_ofs.lnk_cntl);
+       if (!(status32 & BWD_CNTL_LINK_DOWN)) {
+               unsigned char speed, width;
+               u16 status16;
+
+               status16 = readw(ndev->reg_ofs.lnk_stat);
+               width = (status16 & NTB_LINK_WIDTH_MASK) >> 4;
+               speed = (status16 & NTB_LINK_SPEED_MASK);
+               if (ndev->link_width != width || ndev->link_speed != speed)
+                       goto retry;
+       }
+
+       schedule_delayed_work(&ndev->hb_timer, NTB_HB_TIMEOUT);
+       return;
+
+retry:
+       schedule_delayed_work(&ndev->lr_timer, NTB_HB_TIMEOUT);
+}
+
+/* BWD doesn't have link status interrupt, poll on that platform */
+static void bwd_link_poll(struct work_struct *work)
+{
+       struct ntb_device *ndev = container_of(work, struct ntb_device,
+                                              hb_timer.work);
+       unsigned long ts = jiffies;
+
+       /* If we haven't gotten an interrupt in a while, check the BWD link
+        * status bit
+        */
+       if (ts > ndev->last_ts + NTB_HB_TIMEOUT) {
+               int rc = ntb_link_status(ndev);
+               if (rc)
+                       dev_err(&ndev->pdev->dev,
+                               "Error determining link status\n");
+
+               /* Check to see if a link error is the cause of the link down */
+               if (ndev->link_status == NTB_LINK_DOWN) {
+                       u32 status32 = readl(ndev->reg_base +
+                                            BWD_LTSSMSTATEJMP_OFFSET);
+                       if (status32 & BWD_LTSSMSTATEJMP_FORCEDETECT) {
+                               schedule_delayed_work(&ndev->lr_timer, 0);
+                               return;
+                       }
+               }
+       }
+
+       schedule_delayed_work(&ndev->hb_timer, NTB_HB_TIMEOUT);
+}
+
+static int ntb_xeon_setup(struct ntb_device *ndev)
+{
+       switch (ndev->conn_type) {
+       case NTB_CONN_B2B:
+               ndev->reg_ofs.ldb = ndev->reg_base + SNB_PDOORBELL_OFFSET;
+               ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_PDBMSK_OFFSET;
+               ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET;
+               ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_SBAR2XLAT_OFFSET;
+               ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_SBAR4XLAT_OFFSET;
+               if (ndev->split_bar)
+                       ndev->reg_ofs.bar5_xlat =
+                               ndev->reg_base + SNB_SBAR5XLAT_OFFSET;
+               ndev->limits.max_spads = SNB_MAX_B2B_SPADS;
+
+               /* There is a Xeon hardware errata related to writes to
+                * SDOORBELL or B2BDOORBELL in conjunction with inbound access
+                * to NTB MMIO Space, which may hang the system.  To workaround
+                * this use the second memory window to access the interrupt and
+                * scratch pad registers on the remote system.
+                */
+               if (ndev->wa_flags & WA_SNB_ERR) {
+                       if (!ndev->mw[ndev->limits.max_mw - 1].bar_sz)
+                               return -EINVAL;
+
+                       ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
+                       ndev->reg_ofs.spad_write =
+                               ndev->mw[ndev->limits.max_mw - 1].vbase +
+                               SNB_SPAD_OFFSET;
+                       ndev->reg_ofs.rdb =
+                               ndev->mw[ndev->limits.max_mw - 1].vbase +
+                               SNB_PDOORBELL_OFFSET;
+
+                       /* Set the Limit register to 4k, the minimum size, to
+                        * prevent an illegal access
+                        */
+                       writeq(ndev->mw[1].bar_sz + 0x1000, ndev->reg_base +
+                              SNB_PBAR4LMT_OFFSET);
+                       /* HW errata on the Limit registers.  They can only be
+                        * written when the base register is 4GB aligned and
+                        * < 32bit.  This should already be the case based on
+                        * the driver defaults, but write the Limit registers
+                        * first just in case.
+                        */
+
+                       ndev->limits.max_mw = SNB_ERRATA_MAX_MW;
+               } else {
+                       /* HW Errata on bit 14 of b2bdoorbell register.  Writes
+                        * will not be mirrored to the remote system.  Shrink
+                        * the number of bits by one, since bit 14 is the last
+                        * bit.
+                        */
+                       ndev->limits.max_db_bits = SNB_MAX_DB_BITS - 1;
+                       ndev->reg_ofs.spad_write = ndev->reg_base +
+                                                  SNB_B2B_SPAD_OFFSET;
+                       ndev->reg_ofs.rdb = ndev->reg_base +
+                                           SNB_B2B_DOORBELL_OFFSET;
+
+                       /* Disable the Limit register, just incase it is set to
+                        * something silly. A 64bit write should handle it
+                        * regardless of whether it has a split BAR or not.
+                        */
+                       writeq(0, ndev->reg_base + SNB_PBAR4LMT_OFFSET);
+                       /* HW errata on the Limit registers.  They can only be
+                        * written when the base register is 4GB aligned and
+                        * < 32bit.  This should already be the case based on
+                        * the driver defaults, but write the Limit registers
+                        * first just in case.
+                        */
+                       if (ndev->split_bar)
+                               ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
+                       else
+                               ndev->limits.max_mw = SNB_MAX_MW;
+               }
+
+               /* The Xeon errata workaround requires setting SBAR Base
+                * addresses to known values, so that the PBAR XLAT can be
+                * pointed at SBAR0 of the remote system.
+                */
+               if (ndev->dev_type == NTB_DEV_USD) {
+                       writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base +
+                              SNB_PBAR2XLAT_OFFSET);
+                       if (ndev->wa_flags & WA_SNB_ERR)
+                               writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base +
+                                      SNB_PBAR4XLAT_OFFSET);
+                       else {
+                               if (ndev->split_bar) {
+                                       writel(SNB_MBAR4_DSD_ADDR,
+                                              ndev->reg_base +
+                                              SNB_PBAR4XLAT_OFFSET);
+                                       writel(SNB_MBAR5_DSD_ADDR,
+                                              ndev->reg_base +
+                                              SNB_PBAR5XLAT_OFFSET);
+                               } else
+                                       writeq(SNB_MBAR4_DSD_ADDR,
+                                              ndev->reg_base +
+                                              SNB_PBAR4XLAT_OFFSET);
+
+                               /* B2B_XLAT_OFFSET is a 64bit register, but can
+                                * only take 32bit writes
+                                */
+                               writel(SNB_MBAR01_DSD_ADDR & 0xffffffff,
+                                      ndev->reg_base + SNB_B2B_XLAT_OFFSETL);
+                               writel(SNB_MBAR01_DSD_ADDR >> 32,
+                                      ndev->reg_base + SNB_B2B_XLAT_OFFSETU);
+                       }
+
+                       writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base +
+                              SNB_SBAR0BASE_OFFSET);
+                       writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base +
+                              SNB_SBAR2BASE_OFFSET);
+                       if (ndev->split_bar) {
+                               writel(SNB_MBAR4_USD_ADDR, ndev->reg_base +
+                                      SNB_SBAR4BASE_OFFSET);
+                               writel(SNB_MBAR5_USD_ADDR, ndev->reg_base +
+                                      SNB_SBAR5BASE_OFFSET);
+                       } else
+                               writeq(SNB_MBAR4_USD_ADDR, ndev->reg_base +
+                                      SNB_SBAR4BASE_OFFSET);
+               } else {
+                       writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base +
+                              SNB_PBAR2XLAT_OFFSET);
+                       if (ndev->wa_flags & WA_SNB_ERR)
+                               writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base +
+                                      SNB_PBAR4XLAT_OFFSET);
+                       else {
+                               if (ndev->split_bar) {
+                                       writel(SNB_MBAR4_USD_ADDR,
+                                              ndev->reg_base +
+                                              SNB_PBAR4XLAT_OFFSET);
+                                       writel(SNB_MBAR5_USD_ADDR,
+                                              ndev->reg_base +
+                                              SNB_PBAR5XLAT_OFFSET);
+                               } else
+                                       writeq(SNB_MBAR4_USD_ADDR,
+                                              ndev->reg_base +
+                                              SNB_PBAR4XLAT_OFFSET);
+
+                               /*
+                                * B2B_XLAT_OFFSET is a 64bit register, but can
+                                * only take 32bit writes
+                                */
+                               writel(SNB_MBAR01_USD_ADDR & 0xffffffff,
+                                      ndev->reg_base + SNB_B2B_XLAT_OFFSETL);
+                               writel(SNB_MBAR01_USD_ADDR >> 32,
+                                      ndev->reg_base + SNB_B2B_XLAT_OFFSETU);
+                       }
+                       writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base +
+                              SNB_SBAR0BASE_OFFSET);
+                       writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base +
+                              SNB_SBAR2BASE_OFFSET);
+                       if (ndev->split_bar) {
+                               writel(SNB_MBAR4_DSD_ADDR, ndev->reg_base +
+                                      SNB_SBAR4BASE_OFFSET);
+                               writel(SNB_MBAR5_DSD_ADDR, ndev->reg_base +
+                                      SNB_SBAR5BASE_OFFSET);
+                       } else
+                               writeq(SNB_MBAR4_DSD_ADDR, ndev->reg_base +
+                                      SNB_SBAR4BASE_OFFSET);
+
+               }
+               break;
+       case NTB_CONN_RP:
+               if (ndev->wa_flags & WA_SNB_ERR) {
+                       dev_err(&ndev->pdev->dev,
+                               "NTB-RP disabled due to hardware errata.\n");
+                       return -EINVAL;
+               }
+
+               /* Scratch pads need to have exclusive access from the primary
+                * or secondary side.  Halve the num spads so that each side can
+                * have an equal amount.
+                */
+               ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2;
+               ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
+               /* Note: The SDOORBELL is the cause of the errata.  You REALLY
+                * don't want to touch it.
+                */
+               ndev->reg_ofs.rdb = ndev->reg_base + SNB_SDOORBELL_OFFSET;
+               ndev->reg_ofs.ldb = ndev->reg_base + SNB_PDOORBELL_OFFSET;
+               ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_PDBMSK_OFFSET;
+               /* Offset the start of the spads to correspond to whether it is
+                * primary or secondary
+                */
+               ndev->reg_ofs.spad_write = ndev->reg_base + SNB_SPAD_OFFSET +
+                                          ndev->limits.max_spads * 4;
+               ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET;
+               ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_SBAR2XLAT_OFFSET;
+               ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_SBAR4XLAT_OFFSET;
+               if (ndev->split_bar) {
+                       ndev->reg_ofs.bar5_xlat =
+                               ndev->reg_base + SNB_SBAR5XLAT_OFFSET;
+                       ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
+               } else
+                       ndev->limits.max_mw = SNB_MAX_MW;
+               break;
+       case NTB_CONN_TRANSPARENT:
+               if (ndev->wa_flags & WA_SNB_ERR) {
+                       dev_err(&ndev->pdev->dev,
+                               "NTB-TRANSPARENT disabled due to hardware errata.\n");
+                       return -EINVAL;
+               }
+
+               /* Scratch pads need to have exclusive access from the primary
+                * or secondary side.  Halve the num spads so that each side can
+                * have an equal amount.
+                */
+               ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2;
+               ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
+               ndev->reg_ofs.rdb = ndev->reg_base + SNB_PDOORBELL_OFFSET;
+               ndev->reg_ofs.ldb = ndev->reg_base + SNB_SDOORBELL_OFFSET;
+               ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_SDBMSK_OFFSET;
+               ndev->reg_ofs.spad_write = ndev->reg_base + SNB_SPAD_OFFSET;
+               /* Offset the start of the spads to correspond to whether it is
+                * primary or secondary
+                */
+               ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET +
+                                         ndev->limits.max_spads * 4;
+               ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_PBAR2XLAT_OFFSET;
+               ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_PBAR4XLAT_OFFSET;
+
+               if (ndev->split_bar) {
+                       ndev->reg_ofs.bar5_xlat =
+                               ndev->reg_base + SNB_PBAR5XLAT_OFFSET;
+                       ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
+               } else
+                       ndev->limits.max_mw = SNB_MAX_MW;
+               break;
+       default:
+               /*
+                * we should never hit this. the detect function should've
+                * take cared of everything.
+                */
+               return -EINVAL;
+       }
+
+       ndev->reg_ofs.lnk_cntl = ndev->reg_base + SNB_NTBCNTL_OFFSET;
+       ndev->reg_ofs.lnk_stat = ndev->reg_base + SNB_SLINK_STATUS_OFFSET;
+       ndev->reg_ofs.spci_cmd = ndev->reg_base + SNB_PCICMD_OFFSET;
+
+       ndev->limits.msix_cnt = SNB_MSIX_CNT;
+       ndev->bits_per_vector = SNB_DB_BITS_PER_VEC;
+
+       return 0;
+}
+
+static int ntb_bwd_setup(struct ntb_device *ndev)
+{
+       int rc;
+       u32 val;
+
+       ndev->hw_type = BWD_HW;
+
+       rc = pci_read_config_dword(ndev->pdev, NTB_PPD_OFFSET, &val);
+       if (rc)
+               return rc;
+
+       switch ((val & BWD_PPD_CONN_TYPE) >> 8) {
+       case NTB_CONN_B2B:
+               ndev->conn_type = NTB_CONN_B2B;
+               break;
+       case NTB_CONN_RP:
+       default:
+               dev_err(&ndev->pdev->dev, "Unsupported NTB configuration\n");
+               return -EINVAL;
+       }
+
+       if (val & BWD_PPD_DEV_TYPE)
+               ndev->dev_type = NTB_DEV_DSD;
+       else
+               ndev->dev_type = NTB_DEV_USD;
+
+       /* Initiate PCI-E link training */
+       rc = pci_write_config_dword(ndev->pdev, NTB_PPD_OFFSET,
+                                   val | BWD_PPD_INIT_LINK);
+       if (rc)
+               return rc;
+
+       ndev->reg_ofs.ldb = ndev->reg_base + BWD_PDOORBELL_OFFSET;
+       ndev->reg_ofs.ldb_mask = ndev->reg_base + BWD_PDBMSK_OFFSET;
+       ndev->reg_ofs.rdb = ndev->reg_base + BWD_B2B_DOORBELL_OFFSET;
+       ndev->reg_ofs.bar2_xlat = ndev->reg_base + BWD_SBAR2XLAT_OFFSET;
+       ndev->reg_ofs.bar4_xlat = ndev->reg_base + BWD_SBAR4XLAT_OFFSET;
+       ndev->reg_ofs.lnk_cntl = ndev->reg_base + BWD_NTBCNTL_OFFSET;
+       ndev->reg_ofs.lnk_stat = ndev->reg_base + BWD_LINK_STATUS_OFFSET;
+       ndev->reg_ofs.spad_read = ndev->reg_base + BWD_SPAD_OFFSET;
+       ndev->reg_ofs.spad_write = ndev->reg_base + BWD_B2B_SPAD_OFFSET;
+       ndev->reg_ofs.spci_cmd = ndev->reg_base + BWD_PCICMD_OFFSET;
+       ndev->limits.max_mw = BWD_MAX_MW;
+       ndev->limits.max_spads = BWD_MAX_SPADS;
+       ndev->limits.max_db_bits = BWD_MAX_DB_BITS;
+       ndev->limits.msix_cnt = BWD_MSIX_CNT;
+       ndev->bits_per_vector = BWD_DB_BITS_PER_VEC;
+
+       /* Since bwd doesn't have a link interrupt, setup a poll timer */
+       INIT_DELAYED_WORK(&ndev->hb_timer, bwd_link_poll);
+       INIT_DELAYED_WORK(&ndev->lr_timer, bwd_link_recovery);
+       schedule_delayed_work(&ndev->hb_timer, NTB_HB_TIMEOUT);
+
+       return 0;
+}
+
+static int ntb_device_setup(struct ntb_device *ndev)
+{
+       int rc;
+
+       if (is_ntb_xeon(ndev))
+               rc = ntb_xeon_setup(ndev);
+       else if (is_ntb_atom(ndev))
+               rc = ntb_bwd_setup(ndev);
+       else
+               rc = -ENODEV;
+
+       if (rc)
+               return rc;
+
+       if (ndev->conn_type == NTB_CONN_B2B)
+               /* Enable Bus Master and Memory Space on the secondary side */
+               writew(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER,
+                      ndev->reg_ofs.spci_cmd);
+
+       return 0;
+}
+
+static void ntb_device_free(struct ntb_device *ndev)
+{
+       if (is_ntb_atom(ndev)) {
+               cancel_delayed_work_sync(&ndev->hb_timer);
+               cancel_delayed_work_sync(&ndev->lr_timer);
+       }
+}
+
+static irqreturn_t bwd_callback_msix_irq(int irq, void *data)
+{
+       struct ntb_db_cb *db_cb = data;
+       struct ntb_device *ndev = db_cb->ndev;
+       unsigned long mask;
+
+       dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq,
+               db_cb->db_num);
+
+       mask = readw(ndev->reg_ofs.ldb_mask);
+       set_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+       writew(mask, ndev->reg_ofs.ldb_mask);
+
+       tasklet_schedule(&db_cb->irq_work);
+
+       /* No need to check for the specific HB irq, any interrupt means
+        * we're connected.
+        */
+       ndev->last_ts = jiffies;
+
+       writeq((u64) 1 << db_cb->db_num, ndev->reg_ofs.ldb);
+
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t xeon_callback_msix_irq(int irq, void *data)
+{
+       struct ntb_db_cb *db_cb = data;
+       struct ntb_device *ndev = db_cb->ndev;
+       unsigned long mask;
+
+       dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq,
+               db_cb->db_num);
+
+       mask = readw(ndev->reg_ofs.ldb_mask);
+       set_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+       writew(mask, ndev->reg_ofs.ldb_mask);
+
+       tasklet_schedule(&db_cb->irq_work);
+
+       /* On Sandybridge, there are 16 bits in the interrupt register
+        * but only 4 vectors.  So, 5 bits are assigned to the first 3
+        * vectors, with the 4th having a single bit for link
+        * interrupts.
+        */
+       writew(((1 << ndev->bits_per_vector) - 1) <<
+              (db_cb->db_num * ndev->bits_per_vector), ndev->reg_ofs.ldb);
+
+       return IRQ_HANDLED;
+}
+
+/* Since we do not have a HW doorbell in BWD, this is only used in JF/JT */
+static irqreturn_t xeon_event_msix_irq(int irq, void *dev)
+{
+       struct ntb_device *ndev = dev;
+       int rc;
+
+       dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for Events\n", irq);
+
+       rc = ntb_link_status(ndev);
+       if (rc)
+               dev_err(&ndev->pdev->dev, "Error determining link status\n");
+
+       /* bit 15 is always the link bit */
+       writew(1 << SNB_LINK_DB, ndev->reg_ofs.ldb);
+
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t ntb_interrupt(int irq, void *dev)
+{
+       struct ntb_device *ndev = dev;
+       unsigned int i = 0;
+
+       if (is_ntb_atom(ndev)) {
+               u64 ldb = readq(ndev->reg_ofs.ldb);
+
+               dev_dbg(&ndev->pdev->dev, "irq %d - ldb = %Lx\n", irq, ldb);
+
+               while (ldb) {
+                       i = __ffs(ldb);
+                       ldb &= ldb - 1;
+                       bwd_callback_msix_irq(irq, &ndev->db_cb[i]);
+               }
+       } else {
+               u16 ldb = readw(ndev->reg_ofs.ldb);
+
+               dev_dbg(&ndev->pdev->dev, "irq %d - ldb = %x\n", irq, ldb);
+
+               if (ldb & SNB_DB_HW_LINK) {
+                       xeon_event_msix_irq(irq, dev);
+                       ldb &= ~SNB_DB_HW_LINK;
+               }
+
+               while (ldb) {
+                       i = __ffs(ldb);
+                       ldb &= ldb - 1;
+                       xeon_callback_msix_irq(irq, &ndev->db_cb[i]);
+               }
+       }
+
+       return IRQ_HANDLED;
+}
+
+static int ntb_setup_snb_msix(struct ntb_device *ndev, int msix_entries)
+{
+       struct pci_dev *pdev = ndev->pdev;
+       struct msix_entry *msix;
+       int rc, i;
+
+       if (msix_entries < ndev->limits.msix_cnt)
+               return -ENOSPC;
+
+       rc = pci_enable_msix_exact(pdev, ndev->msix_entries, msix_entries);
+       if (rc < 0)
+               return rc;
+
+       for (i = 0; i < msix_entries; i++) {
+               msix = &ndev->msix_entries[i];
+               WARN_ON(!msix->vector);
+
+               if (i == msix_entries - 1) {
+                       rc = request_irq(msix->vector,
+                                        xeon_event_msix_irq, 0,
+                                        "ntb-event-msix", ndev);
+                       if (rc)
+                               goto err;
+               } else {
+                       rc = request_irq(msix->vector,
+                                        xeon_callback_msix_irq, 0,
+                                        "ntb-callback-msix",
+                                        &ndev->db_cb[i]);
+                       if (rc)
+                               goto err;
+               }
+       }
+
+       ndev->num_msix = msix_entries;
+       ndev->max_cbs = msix_entries - 1;
+
+       return 0;
+
+err:
+       while (--i >= 0) {
+               /* Code never reaches here for entry nr 'ndev->num_msix - 1' */
+               msix = &ndev->msix_entries[i];
+               free_irq(msix->vector, &ndev->db_cb[i]);
+       }
+
+       pci_disable_msix(pdev);
+       ndev->num_msix = 0;
+
+       return rc;
+}
+
+static int ntb_setup_bwd_msix(struct ntb_device *ndev, int msix_entries)
+{
+       struct pci_dev *pdev = ndev->pdev;
+       struct msix_entry *msix;
+       int rc, i;
+
+       msix_entries = pci_enable_msix_range(pdev, ndev->msix_entries,
+                                            1, msix_entries);
+       if (msix_entries < 0)
+               return msix_entries;
+
+       for (i = 0; i < msix_entries; i++) {
+               msix = &ndev->msix_entries[i];
+               WARN_ON(!msix->vector);
+
+               rc = request_irq(msix->vector, bwd_callback_msix_irq, 0,
+                                "ntb-callback-msix", &ndev->db_cb[i]);
+               if (rc)
+                       goto err;
+       }
+
+       ndev->num_msix = msix_entries;
+       ndev->max_cbs = msix_entries;
+
+       return 0;
+
+err:
+       while (--i >= 0)
+               free_irq(msix->vector, &ndev->db_cb[i]);
+
+       pci_disable_msix(pdev);
+       ndev->num_msix = 0;
+
+       return rc;
+}
+
+static int ntb_setup_msix(struct ntb_device *ndev)
+{
+       struct pci_dev *pdev = ndev->pdev;
+       int msix_entries;
+       int rc, i;
+
+       msix_entries = pci_msix_vec_count(pdev);
+       if (msix_entries < 0) {
+               rc = msix_entries;
+               goto err;
+       } else if (msix_entries > ndev->limits.msix_cnt) {
+               rc = -EINVAL;
+               goto err;
+       }
+
+       ndev->msix_entries = kmalloc(sizeof(struct msix_entry) * msix_entries,
+                                    GFP_KERNEL);
+       if (!ndev->msix_entries) {
+               rc = -ENOMEM;
+               goto err;
+       }
+
+       for (i = 0; i < msix_entries; i++)
+               ndev->msix_entries[i].entry = i;
+
+       if (is_ntb_atom(ndev))
+               rc = ntb_setup_bwd_msix(ndev, msix_entries);
+       else
+               rc = ntb_setup_snb_msix(ndev, msix_entries);
+       if (rc)
+               goto err1;
+
+       return 0;
+
+err1:
+       kfree(ndev->msix_entries);
+err:
+       dev_err(&pdev->dev, "Error allocating MSI-X interrupt\n");
+       return rc;
+}
+
+static int ntb_setup_msi(struct ntb_device *ndev)
+{
+       struct pci_dev *pdev = ndev->pdev;
+       int rc;
+
+       rc = pci_enable_msi(pdev);
+       if (rc)
+               return rc;
+
+       rc = request_irq(pdev->irq, ntb_interrupt, 0, "ntb-msi", ndev);
+       if (rc) {
+               pci_disable_msi(pdev);
+               dev_err(&pdev->dev, "Error allocating MSI interrupt\n");
+               return rc;
+       }
+
+       return 0;
+}
+
+static int ntb_setup_intx(struct ntb_device *ndev)
+{
+       struct pci_dev *pdev = ndev->pdev;
+       int rc;
+
+       pci_msi_off(pdev);
+
+       /* Verify intx is enabled */
+       pci_intx(pdev, 1);
+
+       rc = request_irq(pdev->irq, ntb_interrupt, IRQF_SHARED, "ntb-intx",
+                        ndev);
+       if (rc)
+               return rc;
+
+       return 0;
+}
+
+static int ntb_setup_interrupts(struct ntb_device *ndev)
+{
+       int rc;
+
+       /* On BWD, disable all interrupts.  On SNB, disable all but Link
+        * Interrupt.  The rest will be unmasked as callbacks are registered.
+        */
+       if (is_ntb_atom(ndev))
+               writeq(~0, ndev->reg_ofs.ldb_mask);
+       else {
+               u16 var = 1 << SNB_LINK_DB;
+               writew(~var, ndev->reg_ofs.ldb_mask);
+       }
+
+       rc = ntb_setup_msix(ndev);
+       if (!rc)
+               goto done;
+
+       ndev->bits_per_vector = 1;
+       ndev->max_cbs = ndev->limits.max_db_bits;
+
+       rc = ntb_setup_msi(ndev);
+       if (!rc)
+               goto done;
+
+       rc = ntb_setup_intx(ndev);
+       if (rc) {
+               dev_err(&ndev->pdev->dev, "no usable interrupts\n");
+               return rc;
+       }
+
+done:
+       return 0;
+}
+
+static void ntb_free_interrupts(struct ntb_device *ndev)
+{
+       struct pci_dev *pdev = ndev->pdev;
+
+       /* mask interrupts */
+       if (is_ntb_atom(ndev))
+               writeq(~0, ndev->reg_ofs.ldb_mask);
+       else
+               writew(~0, ndev->reg_ofs.ldb_mask);
+
+       if (ndev->num_msix) {
+               struct msix_entry *msix;
+               u32 i;
+
+               for (i = 0; i < ndev->num_msix; i++) {
+                       msix = &ndev->msix_entries[i];
+                       if (is_ntb_xeon(ndev) && i == ndev->num_msix - 1)
+                               free_irq(msix->vector, ndev);
+                       else
+                               free_irq(msix->vector, &ndev->db_cb[i]);
+               }
+               pci_disable_msix(pdev);
+               kfree(ndev->msix_entries);
+       } else {
+               free_irq(pdev->irq, ndev);
+
+               if (pci_dev_msi_enabled(pdev))
+                       pci_disable_msi(pdev);
+       }
+}
+
+static int ntb_create_callbacks(struct ntb_device *ndev)
+{
+       int i;
+
+       /* Chicken-egg issue.  We won't know how many callbacks are necessary
+        * until we see how many MSI-X vectors we get, but these pointers need
+        * to be passed into the MSI-X register function.  So, we allocate the
+        * max, knowing that they might not all be used, to work around this.
+        */
+       ndev->db_cb = kcalloc(ndev->limits.max_db_bits,
+                             sizeof(struct ntb_db_cb),
+                             GFP_KERNEL);
+       if (!ndev->db_cb)
+               return -ENOMEM;
+
+       for (i = 0; i < ndev->limits.max_db_bits; i++) {
+               ndev->db_cb[i].db_num = i;
+               ndev->db_cb[i].ndev = ndev;
+       }
+
+       return 0;
+}
+
+static void ntb_free_callbacks(struct ntb_device *ndev)
+{
+       int i;
+
+       for (i = 0; i < ndev->limits.max_db_bits; i++)
+               ntb_unregister_db_callback(ndev, i);
+
+       kfree(ndev->db_cb);
+}
+
+static ssize_t ntb_debugfs_read(struct file *filp, char __user *ubuf,
+                               size_t count, loff_t *offp)
+{
+       struct ntb_device *ndev;
+       char *buf;
+       ssize_t ret, offset, out_count;
+
+       out_count = 500;
+
+       buf = kmalloc(out_count, GFP_KERNEL);
+       if (!buf)
+               return -ENOMEM;
+
+       ndev = filp->private_data;
+       offset = 0;
+       offset += snprintf(buf + offset, out_count - offset,
+                          "NTB Device Information:\n");
+       offset += snprintf(buf + offset, out_count - offset,
+                          "Connection Type - \t\t%s\n",
+                          ndev->conn_type == NTB_CONN_TRANSPARENT ?
+                          "Transparent" : (ndev->conn_type == NTB_CONN_B2B) ?
+                          "Back to back" : "Root Port");
+       offset += snprintf(buf + offset, out_count - offset,
+                          "Device Type - \t\t\t%s\n",
+                          ndev->dev_type == NTB_DEV_USD ?
+                          "DSD/USP" : "USD/DSP");
+       offset += snprintf(buf + offset, out_count - offset,
+                          "Max Number of Callbacks - \t%u\n",
+                          ntb_max_cbs(ndev));
+       offset += snprintf(buf + offset, out_count - offset,
+                          "Link Status - \t\t\t%s\n",
+                          ntb_hw_link_status(ndev) ? "Up" : "Down");
+       if (ntb_hw_link_status(ndev)) {
+               offset += snprintf(buf + offset, out_count - offset,
+                                  "Link Speed - \t\t\tPCI-E Gen %u\n",
+                                  ndev->link_speed);
+               offset += snprintf(buf + offset, out_count - offset,
+                                  "Link Width - \t\t\tx%u\n",
+                                  ndev->link_width);
+       }
+
+       if (is_ntb_xeon(ndev)) {
+               u32 status32;
+               u16 status16;
+               int rc;
+
+               offset += snprintf(buf + offset, out_count - offset,
+                                  "\nNTB Device Statistics:\n");
+               offset += snprintf(buf + offset, out_count - offset,
+                                  "Upstream Memory Miss - \t%u\n",
+                                  readw(ndev->reg_base +
+                                        SNB_USMEMMISS_OFFSET));
+
+               offset += snprintf(buf + offset, out_count - offset,
+                                  "\nNTB Hardware Errors:\n");
+
+               rc = pci_read_config_word(ndev->pdev, SNB_DEVSTS_OFFSET,
+                                         &status16);
+               if (!rc)
+                       offset += snprintf(buf + offset, out_count - offset,
+                                          "DEVSTS - \t%#06x\n", status16);
+
+               rc = pci_read_config_word(ndev->pdev, SNB_LINK_STATUS_OFFSET,
+                                         &status16);
+               if (!rc)
+                       offset += snprintf(buf + offset, out_count - offset,
+                                          "LNKSTS - \t%#06x\n", status16);
+
+               rc = pci_read_config_dword(ndev->pdev, SNB_UNCERRSTS_OFFSET,
+                                          &status32);
+               if (!rc)
+                       offset += snprintf(buf + offset, out_count - offset,
+                                          "UNCERRSTS - \t%#010x\n", status32);
+
+               rc = pci_read_config_dword(ndev->pdev, SNB_CORERRSTS_OFFSET,
+                                          &status32);
+               if (!rc)
+                       offset += snprintf(buf + offset, out_count - offset,
+                                          "CORERRSTS - \t%#010x\n", status32);
+       }
+
+       if (offset > out_count)
+               offset = out_count;
+
+       ret = simple_read_from_buffer(ubuf, count, offp, buf, offset);
+       kfree(buf);
+       return ret;
+}
+
+static const struct file_operations ntb_debugfs_info = {
+       .owner = THIS_MODULE,
+       .open = simple_open,
+       .read = ntb_debugfs_read,
+};
+
+static void ntb_setup_debugfs(struct ntb_device *ndev)
+{
+       if (!debugfs_initialized())
+               return;
+
+       if (!debugfs_dir)
+               debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
+
+       ndev->debugfs_dir = debugfs_create_dir(pci_name(ndev->pdev),
+                                              debugfs_dir);
+       if (ndev->debugfs_dir)
+               ndev->debugfs_info = debugfs_create_file("info", S_IRUSR,
+                                                        ndev->debugfs_dir,
+                                                        ndev,
+                                                        &ntb_debugfs_info);
+}
+
+static void ntb_free_debugfs(struct ntb_device *ndev)
+{
+       debugfs_remove_recursive(ndev->debugfs_dir);
+
+       if (debugfs_dir && simple_empty(debugfs_dir)) {
+               debugfs_remove_recursive(debugfs_dir);
+               debugfs_dir = NULL;
+       }
+}
+
+static void ntb_hw_link_up(struct ntb_device *ndev)
+{
+       if (ndev->conn_type == NTB_CONN_TRANSPARENT)
+               ntb_link_event(ndev, NTB_LINK_UP);
+       else {
+               u32 ntb_cntl;
+
+               /* Let's bring the NTB link up */
+               ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+               ntb_cntl &= ~(NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK);
+               ntb_cntl |= NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP;
+               ntb_cntl |= NTB_CNTL_P2S_BAR4_SNOOP | NTB_CNTL_S2P_BAR4_SNOOP;
+               if (ndev->split_bar)
+                       ntb_cntl |= NTB_CNTL_P2S_BAR5_SNOOP |
+                                   NTB_CNTL_S2P_BAR5_SNOOP;
+
+               writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+       }
+}
+
+static void ntb_hw_link_down(struct ntb_device *ndev)
+{
+       u32 ntb_cntl;
+
+       if (ndev->conn_type == NTB_CONN_TRANSPARENT) {
+               ntb_link_event(ndev, NTB_LINK_DOWN);
+               return;
+       }
+
+       /* Bring NTB link down */
+       ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+       ntb_cntl &= ~(NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP);
+       ntb_cntl &= ~(NTB_CNTL_P2S_BAR4_SNOOP | NTB_CNTL_S2P_BAR4_SNOOP);
+       if (ndev->split_bar)
+               ntb_cntl &= ~(NTB_CNTL_P2S_BAR5_SNOOP |
+                             NTB_CNTL_S2P_BAR5_SNOOP);
+       ntb_cntl |= NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK;
+       writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+}
+
+static void ntb_max_mw_detect(struct ntb_device *ndev)
+{
+       if (ndev->split_bar)
+               ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
+       else
+               ndev->limits.max_mw = SNB_MAX_MW;
+}
+
+static int ntb_xeon_detect(struct ntb_device *ndev)
+{
+       int rc, bars_mask;
+       u32 bars;
+       u8 ppd;
+
+       ndev->hw_type = SNB_HW;
+
+       rc = pci_read_config_byte(ndev->pdev, NTB_PPD_OFFSET, &ppd);
+       if (rc)
+               return -EIO;
+
+       if (ppd & SNB_PPD_DEV_TYPE)
+               ndev->dev_type = NTB_DEV_USD;
+       else
+               ndev->dev_type = NTB_DEV_DSD;
+
+       ndev->split_bar = (ppd & SNB_PPD_SPLIT_BAR) ? 1 : 0;
+
+       switch (ppd & SNB_PPD_CONN_TYPE) {
+       case NTB_CONN_B2B:
+               dev_info(&ndev->pdev->dev, "Conn Type = B2B\n");
+               ndev->conn_type = NTB_CONN_B2B;
+               break;
+       case NTB_CONN_RP:
+               dev_info(&ndev->pdev->dev, "Conn Type = RP\n");
+               ndev->conn_type = NTB_CONN_RP;
+               break;
+       case NTB_CONN_TRANSPARENT:
+               dev_info(&ndev->pdev->dev, "Conn Type = TRANSPARENT\n");
+               ndev->conn_type = NTB_CONN_TRANSPARENT;
+               /*
+                * This mode is default to USD/DSP. HW does not report
+                * properly in transparent mode as it has no knowledge of
+                * NTB. We will just force correct here.
+                */
+               ndev->dev_type = NTB_DEV_USD;
+
+               /*
+                * This is a way for transparent BAR to figure out if we
+                * are doing split BAR or not. There is no way for the hw
+                * on the transparent side to know and set the PPD.
+                */
+               bars_mask = pci_select_bars(ndev->pdev, IORESOURCE_MEM);
+               bars = hweight32(bars_mask);
+               if (bars == (HSX_SPLITBAR_MAX_MW + 1))
+                       ndev->split_bar = 1;
+
+               break;
+       default:
+               dev_err(&ndev->pdev->dev, "Unknown PPD %x\n", ppd);
+               return -ENODEV;
+       }
+
+       ntb_max_mw_detect(ndev);
+
+       return 0;
+}
+
+static int ntb_atom_detect(struct ntb_device *ndev)
+{
+       int rc;
+       u32 ppd;
+
+       ndev->hw_type = BWD_HW;
+       ndev->limits.max_mw = BWD_MAX_MW;
+
+       rc = pci_read_config_dword(ndev->pdev, NTB_PPD_OFFSET, &ppd);
+       if (rc)
+               return rc;
+
+       switch ((ppd & BWD_PPD_CONN_TYPE) >> 8) {
+       case NTB_CONN_B2B:
+               dev_info(&ndev->pdev->dev, "Conn Type = B2B\n");
+               ndev->conn_type = NTB_CONN_B2B;
+               break;
+       case NTB_CONN_RP:
+       default:
+               dev_err(&ndev->pdev->dev, "Unsupported NTB configuration\n");
+               return -EINVAL;
+       }
+
+       if (ppd & BWD_PPD_DEV_TYPE)
+               ndev->dev_type = NTB_DEV_DSD;
+       else
+               ndev->dev_type = NTB_DEV_USD;
+
+       return 0;
+}
+
+static int ntb_device_detect(struct ntb_device *ndev)
+{
+       int rc;
+
+       if (is_ntb_xeon(ndev))
+               rc = ntb_xeon_detect(ndev);
+       else if (is_ntb_atom(ndev))
+               rc = ntb_atom_detect(ndev);
+       else
+               rc = -ENODEV;
+
+       dev_info(&ndev->pdev->dev, "Device Type = %s\n",
+                ndev->dev_type == NTB_DEV_USD ? "USD/DSP" : "DSD/USP");
+
+       return 0;
+}
+
+static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+       struct ntb_device *ndev;
+       int rc, i;
+
+       ndev = kzalloc(sizeof(struct ntb_device), GFP_KERNEL);
+       if (!ndev)
+               return -ENOMEM;
+
+       ndev->pdev = pdev;
+
+       ntb_set_errata_flags(ndev);
+
+       ndev->link_status = NTB_LINK_DOWN;
+       pci_set_drvdata(pdev, ndev);
+       ntb_setup_debugfs(ndev);
+
+       rc = pci_enable_device(pdev);
+       if (rc)
+               goto err;
+
+       pci_set_master(ndev->pdev);
+
+       rc = ntb_device_detect(ndev);
+       if (rc)
+               goto err;
+
+       ndev->mw = kcalloc(ndev->limits.max_mw, sizeof(struct ntb_mw),
+                          GFP_KERNEL);
+       if (!ndev->mw) {
+               rc = -ENOMEM;
+               goto err1;
+       }
+
+       if (ndev->split_bar)
+               rc = pci_request_selected_regions(pdev, NTB_SPLITBAR_MASK,
+                                                 KBUILD_MODNAME);
+       else
+               rc = pci_request_selected_regions(pdev, NTB_BAR_MASK,
+                                                 KBUILD_MODNAME);
+
+       if (rc)
+               goto err2;
+
+       ndev->reg_base = pci_ioremap_bar(pdev, NTB_BAR_MMIO);
+       if (!ndev->reg_base) {
+               dev_warn(&pdev->dev, "Cannot remap BAR 0\n");
+               rc = -EIO;
+               goto err3;
+       }
+
+       for (i = 0; i < ndev->limits.max_mw; i++) {
+               ndev->mw[i].bar_sz = pci_resource_len(pdev, MW_TO_BAR(i));
+
+               /*
+                * with the errata we need to steal last of the memory
+                * windows for workarounds and they point to MMIO registers.
+                */
+               if ((ndev->wa_flags & WA_SNB_ERR) &&
+                   (i == (ndev->limits.max_mw - 1))) {
+                       ndev->mw[i].vbase =
+                               ioremap_nocache(pci_resource_start(pdev,
+                                                       MW_TO_BAR(i)),
+                                               ndev->mw[i].bar_sz);
+               } else {
+                       ndev->mw[i].vbase =
+                               ioremap_wc(pci_resource_start(pdev,
+                                                       MW_TO_BAR(i)),
+                                          ndev->mw[i].bar_sz);
+               }
+
+               dev_info(&pdev->dev, "MW %d size %llu\n", i,
+                        (unsigned long long) ndev->mw[i].bar_sz);
+               if (!ndev->mw[i].vbase) {
+                       dev_warn(&pdev->dev, "Cannot remap BAR %d\n",
+                                MW_TO_BAR(i));
+                       rc = -EIO;
+                       goto err4;
+               }
+       }
+
+       rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
+       if (rc) {
+               rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+               if (rc)
+                       goto err4;
+
+               dev_warn(&pdev->dev, "Cannot DMA highmem\n");
+       }
+
+       rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
+       if (rc) {
+               rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+               if (rc)
+                       goto err4;
+
+               dev_warn(&pdev->dev, "Cannot DMA consistent highmem\n");
+       }
+
+       rc = ntb_device_setup(ndev);
+       if (rc)
+               goto err4;
+
+       rc = ntb_create_callbacks(ndev);
+       if (rc)
+               goto err5;
+
+       rc = ntb_setup_interrupts(ndev);
+       if (rc)
+               goto err6;
+
+       /* The scratchpad registers keep the values between rmmod/insmod,
+        * blast them now
+        */
+       for (i = 0; i < ndev->limits.max_spads; i++) {
+               ntb_write_local_spad(ndev, i, 0);
+               ntb_write_remote_spad(ndev, i, 0);
+       }
+
+       rc = ntb_transport_init(pdev);
+       if (rc)
+               goto err7;
+
+       ntb_hw_link_up(ndev);
+
+       return 0;
+
+err7:
+       ntb_free_interrupts(ndev);
+err6:
+       ntb_free_callbacks(ndev);
+err5:
+       ntb_device_free(ndev);
+err4:
+       for (i--; i >= 0; i--)
+               iounmap(ndev->mw[i].vbase);
+       iounmap(ndev->reg_base);
+err3:
+       if (ndev->split_bar)
+               pci_release_selected_regions(pdev, NTB_SPLITBAR_MASK);
+       else
+               pci_release_selected_regions(pdev, NTB_BAR_MASK);
+err2:
+       kfree(ndev->mw);
+err1:
+       pci_disable_device(pdev);
+err:
+       ntb_free_debugfs(ndev);
+       kfree(ndev);
+
+       dev_err(&pdev->dev, "Error loading %s module\n", KBUILD_MODNAME);
+       return rc;
+}
+
+static void ntb_pci_remove(struct pci_dev *pdev)
+{
+       struct ntb_device *ndev = pci_get_drvdata(pdev);
+       int i;
+
+       ntb_hw_link_down(ndev);
+
+       ntb_transport_free(ndev->ntb_transport);
+
+       ntb_free_interrupts(ndev);
+       ntb_free_callbacks(ndev);
+       ntb_device_free(ndev);
+
+       /* need to reset max_mw limits so we can unmap properly */
+       if (ndev->hw_type == SNB_HW)
+               ntb_max_mw_detect(ndev);
+
+       for (i = 0; i < ndev->limits.max_mw; i++)
+               iounmap(ndev->mw[i].vbase);
+
+       kfree(ndev->mw);
+       iounmap(ndev->reg_base);
+       if (ndev->split_bar)
+               pci_release_selected_regions(pdev, NTB_SPLITBAR_MASK);
+       else
+               pci_release_selected_regions(pdev, NTB_BAR_MASK);
+       pci_disable_device(pdev);
+       ntb_free_debugfs(ndev);
+       kfree(ndev);
+}
+
+static struct pci_driver ntb_pci_driver = {
+       .name = KBUILD_MODNAME,
+       .id_table = ntb_pci_tbl,
+       .probe = ntb_pci_probe,
+       .remove = ntb_pci_remove,
+};
+
+module_pci_driver(ntb_pci_driver);