ntb: Adding Skylake Xeon NTB support

The Skylake Xeon NTB hardware has made some changes to the register name,
offset, and the way doorbells work. Adding driver support for the new
hardware.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

drivers/ntb/hw/intel/ntb_hw_intel.c

@@ -86,7 +86,12 @@ static const struct intel_ntb_xlat_reg xeon_pri_xlat;
 static const struct intel_ntb_xlat_reg xeon_sec_xlat;
 static struct intel_b2b_addr xeon_b2b_usd_addr;
 static struct intel_b2b_addr xeon_b2b_dsd_addr;
+static const struct intel_ntb_reg skx_reg;
+static const struct intel_ntb_alt_reg skx_pri_reg;
+static const struct intel_ntb_alt_reg skx_b2b_reg;
+static const struct intel_ntb_xlat_reg skx_sec_xlat;
 static const struct ntb_dev_ops intel_ntb_ops;
+static const struct ntb_dev_ops intel_ntb3_ops;
 
 static const struct file_operations intel_ntb_debugfs_info;
 static struct dentry *debugfs_dir;
@@ -145,6 +150,9 @@ module_param_named(xeon_b2b_dsd_bar5_addr32,
 MODULE_PARM_DESC(xeon_b2b_dsd_bar5_addr32,
 		 "XEON B2B DSD split-BAR 5 32-bit address");
 
+static inline enum ntb_topo xeon_ppd_topo(struct intel_ntb_dev *ndev, u8 ppd);
+static int xeon_init_isr(struct intel_ntb_dev *ndev);
+
 #ifndef ioread64
 #ifdef readq
 #define ioread64 readq
@@ -206,6 +214,14 @@ static inline int pdev_is_xeon(struct pci_dev *pdev)
 	return 0;
 }
 
+static inline int pdev_is_skx_xeon(struct pci_dev *pdev)
+{
+	if (pdev->device == PCI_DEVICE_ID_INTEL_NTB_B2B_SKX)
+		return 1;
+
+	return 0;
+}
+
 static inline void ndev_reset_unsafe_flags(struct intel_ntb_dev *ndev)
 {
 	ndev->unsafe_flags = 0;
@@ -390,6 +406,9 @@ static irqreturn_t ndev_interrupt(struct intel_ntb_dev *ndev, int vec)
 
 	vec_mask = ndev_vec_mask(ndev, vec);
 
+	if ((ndev->hwerr_flags & NTB_HWERR_MSIX_VECTOR32_BAD) && (vec == 31))
+		vec_mask |= ndev->db_link_mask;
+
 	dev_dbg(ndev_dev(ndev), "vec %d vec_mask %llx\n", vec, vec_mask);
 
 	ndev->last_ts = jiffies;
@@ -409,6 +428,9 @@ static irqreturn_t ndev_vec_isr(int irq, void *dev)
 {
 	struct intel_ntb_vec *nvec = dev;
 
+	dev_dbg(ndev_dev(nvec->ndev), "irq: %d  nvec->num: %d\n",
+		irq, nvec->num);
+
 	return ndev_interrupt(nvec->ndev, nvec->num);
 }
 
@@ -465,7 +487,7 @@ static int ndev_init_isr(struct intel_ntb_dev *ndev,
 			goto err_msix_request;
 	}
 
-	dev_dbg(ndev_dev(ndev), "Using msix interrupts\n");
+	dev_dbg(ndev_dev(ndev), "Using %d msix interrupts\n", msix_count);
 	ndev->db_vec_count = msix_count;
 	ndev->db_vec_shift = msix_shift;
 	return 0;
@@ -547,7 +569,170 @@ static void ndev_deinit_isr(struct intel_ntb_dev *ndev)
 	}
 }
 
-static ssize_t ndev_debugfs_read(struct file *filp, char __user *ubuf,
+static ssize_t ndev_ntb3_debugfs_read(struct file *filp, char __user *ubuf,
+				      size_t count, loff_t *offp)
+{
+	struct intel_ntb_dev *ndev;
+	void __iomem *mmio;
+	char *buf;
+	size_t buf_size;
+	ssize_t ret, off;
+	union { u64 v64; u32 v32; u16 v16; } u;
+
+	ndev = filp->private_data;
+	mmio = ndev->self_mmio;
+
+	buf_size = min(count, 0x800ul);
+
+	buf = kmalloc(buf_size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	off = 0;
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "NTB Device Information:\n");
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Connection Topology -\t%s\n",
+			 ntb_topo_string(ndev->ntb.topo));
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "NTB CTL -\t\t%#06x\n", ndev->ntb_ctl);
+	off += scnprintf(buf + off, buf_size - off,
+			 "LNK STA -\t\t%#06x\n", ndev->lnk_sta);
+
+	if (!ndev->reg->link_is_up(ndev))
+		off += scnprintf(buf + off, buf_size - off,
+				 "Link Status -\t\tDown\n");
+	else {
+		off += scnprintf(buf + off, buf_size - off,
+				 "Link Status -\t\tUp\n");
+		off += scnprintf(buf + off, buf_size - off,
+				 "Link Speed -\t\tPCI-E Gen %u\n",
+				 NTB_LNK_STA_SPEED(ndev->lnk_sta));
+		off += scnprintf(buf + off, buf_size - off,
+				 "Link Width -\t\tx%u\n",
+				 NTB_LNK_STA_WIDTH(ndev->lnk_sta));
+	}
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Memory Window Count -\t%u\n", ndev->mw_count);
+	off += scnprintf(buf + off, buf_size - off,
+			 "Scratchpad Count -\t%u\n", ndev->spad_count);
+	off += scnprintf(buf + off, buf_size - off,
+			 "Doorbell Count -\t%u\n", ndev->db_count);
+	off += scnprintf(buf + off, buf_size - off,
+			 "Doorbell Vector Count -\t%u\n", ndev->db_vec_count);
+	off += scnprintf(buf + off, buf_size - off,
+			 "Doorbell Vector Shift -\t%u\n", ndev->db_vec_shift);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Doorbell Valid Mask -\t%#llx\n", ndev->db_valid_mask);
+	off += scnprintf(buf + off, buf_size - off,
+			 "Doorbell Link Mask -\t%#llx\n", ndev->db_link_mask);
+	off += scnprintf(buf + off, buf_size - off,
+			 "Doorbell Mask Cached -\t%#llx\n", ndev->db_mask);
+
+	u.v64 = ndev_db_read(ndev, mmio + ndev->self_reg->db_mask);
+	off += scnprintf(buf + off, buf_size - off,
+			 "Doorbell Mask -\t\t%#llx\n", u.v64);
+
+	u.v64 = ndev_db_read(ndev, mmio + ndev->self_reg->db_bell);
+	off += scnprintf(buf + off, buf_size - off,
+			 "Doorbell Bell -\t\t%#llx\n", u.v64);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "\nNTB Incoming XLAT:\n");
+
+	u.v64 = ioread64(mmio + SKX_IMBAR1XBASE_OFFSET);
+	off += scnprintf(buf + off, buf_size - off,
+			 "IMBAR1XBASE -\t\t%#018llx\n", u.v64);
+
+	u.v64 = ioread64(mmio + SKX_IMBAR2XBASE_OFFSET);
+	off += scnprintf(buf + off, buf_size - off,
+			 "IMBAR2XBASE -\t\t%#018llx\n", u.v64);
+
+	u.v64 = ioread64(mmio + SKX_IMBAR1XLMT_OFFSET);
+	off += scnprintf(buf + off, buf_size - off,
+			 "IMBAR1XLMT -\t\t\t%#018llx\n", u.v64);
+
+	u.v64 = ioread64(mmio + SKX_IMBAR2XLMT_OFFSET);
+	off += scnprintf(buf + off, buf_size - off,
+			 "IMBAR2XLMT -\t\t\t%#018llx\n", u.v64);
+
+	if (ntb_topo_is_b2b(ndev->ntb.topo)) {
+		off += scnprintf(buf + off, buf_size - off,
+				 "\nNTB Outgoing B2B XLAT:\n");
+
+		u.v64 = ioread64(mmio + SKX_EMBAR1XBASE_OFFSET);
+		off += scnprintf(buf + off, buf_size - off,
+				 "EMBAR1XBASE -\t\t%#018llx\n", u.v64);
+
+		u.v64 = ioread64(mmio + SKX_EMBAR2XBASE_OFFSET);
+		off += scnprintf(buf + off, buf_size - off,
+				 "EMBAR2XBASE -\t\t%#018llx\n", u.v64);
+
+		u.v64 = ioread64(mmio + SKX_EMBAR1XLMT_OFFSET);
+		off += scnprintf(buf + off, buf_size - off,
+				 "EMBAR1XLMT -\t\t%#018llx\n", u.v64);
+
+		u.v64 = ioread64(mmio + SKX_EMBAR2XLMT_OFFSET);
+		off += scnprintf(buf + off, buf_size - off,
+				 "EMBAR2XLMT -\t\t%#018llx\n", u.v64);
+
+		off += scnprintf(buf + off, buf_size - off,
+				 "\nNTB Secondary BAR:\n");
+
+		u.v64 = ioread64(mmio + SKX_EMBAR0_OFFSET);
+		off += scnprintf(buf + off, buf_size - off,
+				 "EMBAR0 -\t\t%#018llx\n", u.v64);
+
+		u.v64 = ioread64(mmio + SKX_EMBAR1_OFFSET);
+		off += scnprintf(buf + off, buf_size - off,
+				 "EMBAR1 -\t\t%#018llx\n", u.v64);
+
+		u.v64 = ioread64(mmio + SKX_EMBAR2_OFFSET);
+		off += scnprintf(buf + off, buf_size - off,
+				 "EMBAR2 -\t\t%#018llx\n", u.v64);
+	}
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "\nNTB Statistics:\n");
+
+	u.v16 = ioread16(mmio + SKX_USMEMMISS_OFFSET);
+	off += scnprintf(buf + off, buf_size - off,
+			 "Upstream Memory Miss -\t%u\n", u.v16);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "\nNTB Hardware Errors:\n");
+
+	if (!pci_read_config_word(ndev->ntb.pdev,
+				  SKX_DEVSTS_OFFSET, &u.v16))
+		off += scnprintf(buf + off, buf_size - off,
+				 "DEVSTS -\t\t%#06x\n", u.v16);
+
+	if (!pci_read_config_word(ndev->ntb.pdev,
+				  SKX_LINK_STATUS_OFFSET, &u.v16))
+		off += scnprintf(buf + off, buf_size - off,
+				 "LNKSTS -\t\t%#06x\n", u.v16);
+
+	if (!pci_read_config_dword(ndev->ntb.pdev,
+				   SKX_UNCERRSTS_OFFSET, &u.v32))
+		off += scnprintf(buf + off, buf_size - off,
+				 "UNCERRSTS -\t\t%#06x\n", u.v32);
+
+	if (!pci_read_config_dword(ndev->ntb.pdev,
+				   SKX_CORERRSTS_OFFSET, &u.v32))
+		off += scnprintf(buf + off, buf_size - off,
+				 "CORERRSTS -\t\t%#06x\n", u.v32);
+
+	ret = simple_read_from_buffer(ubuf, count, offp, buf, off);
+	kfree(buf);
+	return ret;
+}
+
+static ssize_t ndev_ntb_debugfs_read(struct file *filp, char __user *ubuf,
 				     size_t count, loff_t *offp)
 {
 	struct intel_ntb_dev *ndev;
@@ -813,6 +998,20 @@ static ssize_t ndev_debugfs_read(struct file *filp, char __user *ubuf,
 	return ret;
 }
 
+static ssize_t ndev_debugfs_read(struct file *filp, char __user *ubuf,
+				 size_t count, loff_t *offp)
+{
+	struct intel_ntb_dev *ndev = filp->private_data;
+
+	if (pdev_is_xeon(ndev->ntb.pdev) ||
+	    pdev_is_atom(ndev->ntb.pdev))
+		return ndev_ntb_debugfs_read(filp, ubuf, count, offp);
+	else if (pdev_is_skx_xeon(ndev->ntb.pdev))
+		return ndev_ntb3_debugfs_read(filp, ubuf, count, offp);
+
+	return -ENXIO;
+}
+
 static void ndev_init_debugfs(struct intel_ntb_dev *ndev)
 {
 	if (!debugfs_dir) {
@@ -1428,6 +1627,383 @@ static void atom_deinit_dev(struct intel_ntb_dev *ndev)
 	atom_deinit_isr(ndev);
 }
 
+/* Skylake Xeon NTB */
+
+static u64 skx_db_ioread(void __iomem *mmio)
+{
+	return ioread64(mmio);
+}
+
+static void skx_db_iowrite(u64 bits, void __iomem *mmio)
+{
+	iowrite64(bits, mmio);
+}
+
+static int skx_init_isr(struct intel_ntb_dev *ndev)
+{
+	int i;
+
+	/*
+	 * The MSIX vectors and the interrupt status bits are not lined up
+	 * on Skylake. By default the link status bit is bit 32, however it
+	 * is by default MSIX vector0. We need to fixup to line them up.
+	 * The vectors at reset is 1-32,0. We need to reprogram to 0-32.
+	 */
+
+	for (i = 0; i < SKX_DB_MSIX_VECTOR_COUNT; i++)
+		iowrite8(i, ndev->self_mmio + SKX_INTVEC_OFFSET + i);
+
+	/* move link status down one as workaround */
+	if (ndev->hwerr_flags & NTB_HWERR_MSIX_VECTOR32_BAD) {
+		iowrite8(SKX_DB_MSIX_VECTOR_COUNT - 2,
+			 ndev->self_mmio + SKX_INTVEC_OFFSET +
+			 (SKX_DB_MSIX_VECTOR_COUNT - 1));
+	}
+
+	return ndev_init_isr(ndev, SKX_DB_MSIX_VECTOR_COUNT,
+			     SKX_DB_MSIX_VECTOR_COUNT,
+			     SKX_DB_MSIX_VECTOR_SHIFT,
+			     SKX_DB_TOTAL_SHIFT);
+}
+
+static int skx_setup_b2b_mw(struct intel_ntb_dev *ndev,
+			    const struct intel_b2b_addr *addr,
+			    const struct intel_b2b_addr *peer_addr)
+{
+	struct pci_dev *pdev;
+	void __iomem *mmio;
+	resource_size_t bar_size;
+	phys_addr_t bar_addr;
+	int b2b_bar;
+	u8 bar_sz;
+
+	pdev = ndev_pdev(ndev);
+	mmio = ndev->self_mmio;
+
+	if (ndev->b2b_idx == UINT_MAX) {
+		dev_dbg(ndev_dev(ndev), "not using b2b mw\n");
+		b2b_bar = 0;
+		ndev->b2b_off = 0;
+	} else {
+		b2b_bar = ndev_mw_to_bar(ndev, ndev->b2b_idx);
+		if (b2b_bar < 0)
+			return -EIO;
+
+		dev_dbg(ndev_dev(ndev), "using b2b mw bar %d\n", b2b_bar);
+
+		bar_size = pci_resource_len(ndev->ntb.pdev, b2b_bar);
+
+		dev_dbg(ndev_dev(ndev), "b2b bar size %#llx\n", bar_size);
+
+		if (b2b_mw_share && ((bar_size >> 1) >= XEON_B2B_MIN_SIZE)) {
+			dev_dbg(ndev_dev(ndev),
+				"b2b using first half of bar\n");
+			ndev->b2b_off = bar_size >> 1;
+		} else if (bar_size >= XEON_B2B_MIN_SIZE) {
+			dev_dbg(ndev_dev(ndev),
+				"b2b using whole bar\n");
+			ndev->b2b_off = 0;
+			--ndev->mw_count;
+		} else {
+			dev_dbg(ndev_dev(ndev),
+				"b2b bar size is too small\n");
+			return -EIO;
+		}
+	}
+
+	/*
+	 * Reset the secondary bar sizes to match the primary bar sizes,
+	 * except disable or halve the size of the b2b secondary bar.
+	 */
+	pci_read_config_byte(pdev, SKX_IMBAR1SZ_OFFSET, &bar_sz);
+	dev_dbg(ndev_dev(ndev), "IMBAR1SZ %#x\n", bar_sz);
+	if (b2b_bar == 1) {
+		if (ndev->b2b_off)
+			bar_sz -= 1;
+		else
+			bar_sz = 0;
+	}
+
+	pci_write_config_byte(pdev, SKX_EMBAR1SZ_OFFSET, bar_sz);
+	pci_read_config_byte(pdev, SKX_EMBAR1SZ_OFFSET, &bar_sz);
+	dev_dbg(ndev_dev(ndev), "EMBAR1SZ %#x\n", bar_sz);
+
+	pci_read_config_byte(pdev, SKX_IMBAR2SZ_OFFSET, &bar_sz);
+	dev_dbg(ndev_dev(ndev), "IMBAR2SZ %#x\n", bar_sz);
+	if (b2b_bar == 2) {
+		if (ndev->b2b_off)
+			bar_sz -= 1;
+		else
+			bar_sz = 0;
+	}
+
+	pci_write_config_byte(pdev, SKX_EMBAR2SZ_OFFSET, bar_sz);
+	pci_read_config_byte(pdev, SKX_EMBAR2SZ_OFFSET, &bar_sz);
+	dev_dbg(ndev_dev(ndev), "EMBAR2SZ %#x\n", bar_sz);
+
+	/* SBAR01 hit by first part of the b2b bar */
+	if (b2b_bar == 0)
+		bar_addr = addr->bar0_addr;
+	else if (b2b_bar == 1)
+		bar_addr = addr->bar2_addr64;
+	else if (b2b_bar == 2)
+		bar_addr = addr->bar4_addr64;
+	else
+		return -EIO;
+
+	/* setup incoming bar limits == base addrs (zero length windows) */
+	bar_addr = addr->bar2_addr64 + (b2b_bar == 1 ? ndev->b2b_off : 0);
+	iowrite64(bar_addr, mmio + SKX_IMBAR1XLMT_OFFSET);
+	bar_addr = ioread64(mmio + SKX_IMBAR1XLMT_OFFSET);
+	dev_dbg(ndev_dev(ndev), "IMBAR1XLMT %#018llx\n", bar_addr);
+
+	bar_addr = addr->bar4_addr64 + (b2b_bar == 2 ? ndev->b2b_off : 0);
+	iowrite64(bar_addr, mmio + SKX_IMBAR2XLMT_OFFSET);
+	bar_addr = ioread64(mmio + SKX_IMBAR2XLMT_OFFSET);
+	dev_dbg(ndev_dev(ndev), "IMBAR2XLMT %#018llx\n", bar_addr);
+
+	/* zero incoming translation addrs */
+	iowrite64(0, mmio + SKX_IMBAR1XBASE_OFFSET);
+	iowrite64(0, mmio + SKX_IMBAR2XBASE_OFFSET);
+
+	ndev->peer_mmio = ndev->self_mmio;
+
+	return 0;
+}
+
+static int skx_init_ntb(struct intel_ntb_dev *ndev)
+{
+	int rc;
+
+
+	ndev->mw_count = XEON_MW_COUNT;
+	ndev->spad_count = SKX_SPAD_COUNT;
+	ndev->db_count = SKX_DB_COUNT;
+	ndev->db_link_mask = SKX_DB_LINK_BIT;
+
+	/* DB fixup for using 31 right now */
+	if (ndev->hwerr_flags & NTB_HWERR_MSIX_VECTOR32_BAD)
+		ndev->db_link_mask |= BIT_ULL(31);
+
+	switch (ndev->ntb.topo) {
+	case NTB_TOPO_B2B_USD:
+	case NTB_TOPO_B2B_DSD:
+		ndev->self_reg = &skx_pri_reg;
+		ndev->peer_reg = &skx_b2b_reg;
+		ndev->xlat_reg = &skx_sec_xlat;
+
+		if (ndev->ntb.topo == NTB_TOPO_B2B_USD) {
+			rc = skx_setup_b2b_mw(ndev,
+					      &xeon_b2b_dsd_addr,
+					      &xeon_b2b_usd_addr);
+		} else {
+			rc = skx_setup_b2b_mw(ndev,
+					      &xeon_b2b_usd_addr,
+					      &xeon_b2b_dsd_addr);
+		}
+
+		if (rc)
+			return rc;
+
+		/* Enable Bus Master and Memory Space on the secondary side */
+		iowrite16(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER,
+			  ndev->self_mmio + SKX_SPCICMD_OFFSET);
+
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	ndev->db_valid_mask = BIT_ULL(ndev->db_count) - 1;
+
+	ndev->reg->db_iowrite(ndev->db_valid_mask,
+			      ndev->self_mmio +
+			      ndev->self_reg->db_mask);
+
+	return 0;
+}
+
+static int skx_init_dev(struct intel_ntb_dev *ndev)
+{
+	struct pci_dev *pdev;
+	u8 ppd;
+	int rc;
+
+	pdev = ndev_pdev(ndev);
+
+	ndev->reg = &skx_reg;
+
+	rc = pci_read_config_byte(pdev, XEON_PPD_OFFSET, &ppd);
+	if (rc)
+		return -EIO;
+
+	ndev->ntb.topo = xeon_ppd_topo(ndev, ppd);
+	dev_dbg(ndev_dev(ndev), "ppd %#x topo %s\n", ppd,
+		ntb_topo_string(ndev->ntb.topo));
+	if (ndev->ntb.topo == NTB_TOPO_NONE)
+		return -EINVAL;
+
+	if (pdev_is_skx_xeon(pdev))
+		ndev->hwerr_flags |= NTB_HWERR_MSIX_VECTOR32_BAD;
+
+	rc = skx_init_ntb(ndev);
+	if (rc)
+		return rc;
+
+	return skx_init_isr(ndev);
+}
+
+static int intel_ntb3_link_enable(struct ntb_dev *ntb,
+				  enum ntb_speed max_speed,
+				  enum ntb_width max_width)
+{
+	struct intel_ntb_dev *ndev;
+	u32 ntb_ctl;
+
+	ndev = container_of(ntb, struct intel_ntb_dev, ntb);
+
+	dev_dbg(ndev_dev(ndev),
+		"Enabling link with max_speed %d max_width %d\n",
+		max_speed, max_width);
+
+	if (max_speed != NTB_SPEED_AUTO)
+		dev_dbg(ndev_dev(ndev), "ignoring max_speed %d\n", max_speed);
+	if (max_width != NTB_WIDTH_AUTO)
+		dev_dbg(ndev_dev(ndev), "ignoring max_width %d\n", max_width);
+
+	ntb_ctl = ioread32(ndev->self_mmio + ndev->reg->ntb_ctl);
+	ntb_ctl &= ~(NTB_CTL_DISABLE | NTB_CTL_CFG_LOCK);
+	ntb_ctl |= NTB_CTL_P2S_BAR2_SNOOP | NTB_CTL_S2P_BAR2_SNOOP;
+	ntb_ctl |= NTB_CTL_P2S_BAR4_SNOOP | NTB_CTL_S2P_BAR4_SNOOP;
+	iowrite32(ntb_ctl, ndev->self_mmio + ndev->reg->ntb_ctl);
+
+	return 0;
+}
+static int intel_ntb3_mw_set_trans(struct ntb_dev *ntb, int idx,
+				   dma_addr_t addr, resource_size_t size)
+{
+	struct intel_ntb_dev *ndev = ntb_ndev(ntb);
+	unsigned long xlat_reg, limit_reg;
+	resource_size_t bar_size, mw_size;
+	void __iomem *mmio;
+	u64 base, limit, reg_val;
+	int bar;
+
+	if (idx >= ndev->b2b_idx && !ndev->b2b_off)
+		idx += 1;
+
+	bar = ndev_mw_to_bar(ndev, idx);
+	if (bar < 0)
+		return bar;
+
+	bar_size = pci_resource_len(ndev->ntb.pdev, bar);
+
+	if (idx == ndev->b2b_idx)
+		mw_size = bar_size - ndev->b2b_off;
+	else
+		mw_size = bar_size;
+
+	/* hardware requires that addr is aligned to bar size */
+	if (addr & (bar_size - 1))
+		return -EINVAL;
+
+	/* make sure the range fits in the usable mw size */
+	if (size > mw_size)
+		return -EINVAL;
+
+	mmio = ndev->self_mmio;
+	xlat_reg = ndev->xlat_reg->bar2_xlat + (idx * 0x10);
+	limit_reg = ndev->xlat_reg->bar2_limit + (idx * 0x10);
+	base = pci_resource_start(ndev->ntb.pdev, bar);
+
+	/* Set the limit if supported, if size is not mw_size */
+	if (limit_reg && size != mw_size)
+		limit = base + size;
+	else
+		limit = base + mw_size;
+
+	/* set and verify setting the translation address */
+	iowrite64(addr, mmio + xlat_reg);
+	reg_val = ioread64(mmio + xlat_reg);
+	if (reg_val != addr) {
+		iowrite64(0, mmio + xlat_reg);
+		return -EIO;
+	}
+
+	dev_dbg(ndev_dev(ndev), "BAR %d IMBARXBASE: %#Lx\n", bar, reg_val);
+
+	/* set and verify setting the limit */
+	iowrite64(limit, mmio + limit_reg);
+	reg_val = ioread64(mmio + limit_reg);
+	if (reg_val != limit) {
+		iowrite64(base, mmio + limit_reg);
+		iowrite64(0, mmio + xlat_reg);
+		return -EIO;
+	}
+
+	dev_dbg(ndev_dev(ndev), "BAR %d IMBARXLMT: %#Lx\n", bar, reg_val);
+
+	/* setup the EP */
+	limit_reg = ndev->xlat_reg->bar2_limit + (idx * 0x10) + 0x4000;
+	base = ioread64(mmio + SKX_EMBAR1_OFFSET + (8 * idx));
+	base &= ~0xf;
+
+	if (limit_reg && size != mw_size)
+		limit = base + size;
+	else
+		limit = base + mw_size;
+
+	/* set and verify setting the limit */
+	iowrite64(limit, mmio + limit_reg);
+	reg_val = ioread64(mmio + limit_reg);
+	if (reg_val != limit) {
+		iowrite64(base, mmio + limit_reg);
+		iowrite64(0, mmio + xlat_reg);
+		return -EIO;
+	}
+
+	dev_dbg(ndev_dev(ndev), "BAR %d EMBARXLMT: %#Lx\n", bar, reg_val);
+
+	return 0;
+}
+
+static int intel_ntb3_peer_db_set(struct ntb_dev *ntb, u64 db_bits)
+{
+	struct intel_ntb_dev *ndev = ntb_ndev(ntb);
+	int bit;
+
+	if (db_bits & ~ndev->db_valid_mask)
+		return -EINVAL;
+
+	while (db_bits) {
+		bit = __ffs(db_bits);
+		iowrite32(1, ndev->peer_mmio +
+				ndev->peer_reg->db_bell + (bit * 4));
+		db_bits &= db_bits - 1;
+	}
+
+	return 0;
+}
+
+static u64 intel_ntb3_db_read(struct ntb_dev *ntb)
+{
+	struct intel_ntb_dev *ndev = ntb_ndev(ntb);
+
+	return ndev_db_read(ndev,
+			    ndev->self_mmio +
+			    ndev->self_reg->db_clear);
+}
+
+static int intel_ntb3_db_clear(struct ntb_dev *ntb, u64 db_bits)
+{
+	struct intel_ntb_dev *ndev = ntb_ndev(ntb);
+
+	return ndev_db_write(ndev, db_bits,
+			     ndev->self_mmio +
+			     ndev->self_reg->db_clear);
+}
+
 /* XEON */
 
 static u64 xeon_db_ioread(void __iomem *mmio)
@@ -2120,6 +2696,24 @@ static int intel_ntb_pci_probe(struct pci_dev *pdev,
 		if (rc)
 			goto err_init_dev;
 
+	} else if (pdev_is_skx_xeon(pdev)) {
+		ndev = kzalloc_node(sizeof(*ndev), GFP_KERNEL, node);
+		if (!ndev) {
+			rc = -ENOMEM;
+			goto err_ndev;
+		}
+
+		ndev_init_struct(ndev, pdev);
+		ndev->ntb.ops = &intel_ntb3_ops;
+
+		rc = intel_ntb_init_pci(ndev, pdev);
+		if (rc)
+			goto err_init_pci;
+
+		rc = skx_init_dev(ndev);
+		if (rc)
+			goto err_init_dev;
+
 	} else {
 		rc = -EINVAL;
 		goto err_ndev;
@@ -2143,7 +2737,7 @@ static int intel_ntb_pci_probe(struct pci_dev *pdev,
 	ndev_deinit_debugfs(ndev);
 	if (pdev_is_atom(pdev))
 		atom_deinit_dev(ndev);
-	else if (pdev_is_xeon(pdev))
+	else if (pdev_is_xeon(pdev) || pdev_is_skx_xeon(pdev))
 		xeon_deinit_dev(ndev);
 err_init_dev:
 	intel_ntb_deinit_pci(ndev);
@@ -2161,7 +2755,7 @@ static void intel_ntb_pci_remove(struct pci_dev *pdev)
 	ndev_deinit_debugfs(ndev);
 	if (pdev_is_atom(pdev))
 		atom_deinit_dev(ndev);
-	else if (pdev_is_xeon(pdev))
+	else if (pdev_is_xeon(pdev) || pdev_is_skx_xeon(pdev))
 		xeon_deinit_dev(ndev);
 	intel_ntb_deinit_pci(ndev);
 	kfree(ndev);
@@ -2257,6 +2851,36 @@ static struct intel_b2b_addr xeon_b2b_dsd_addr = {
 	.bar5_addr32		= XEON_B2B_BAR5_ADDR32,
 };
 
+static const struct intel_ntb_reg skx_reg = {
+	.poll_link		= xeon_poll_link,
+	.link_is_up		= xeon_link_is_up,
+	.db_ioread		= skx_db_ioread,
+	.db_iowrite		= skx_db_iowrite,
+	.db_size		= sizeof(u64),
+	.ntb_ctl		= SKX_NTBCNTL_OFFSET,
+	.mw_bar			= {2, 4},
+};
+
+static const struct intel_ntb_alt_reg skx_pri_reg = {
+	.db_bell		= SKX_EM_DOORBELL_OFFSET,
+	.db_clear		= SKX_IM_INT_STATUS_OFFSET,
+	.db_mask		= SKX_IM_INT_DISABLE_OFFSET,
+	.spad			= SKX_IM_SPAD_OFFSET,
+};
+
+static const struct intel_ntb_alt_reg skx_b2b_reg = {
+	.db_bell		= SKX_IM_DOORBELL_OFFSET,
+	.db_clear		= SKX_EM_INT_STATUS_OFFSET,
+	.db_mask		= SKX_EM_INT_DISABLE_OFFSET,
+	.spad			= SKX_B2B_SPAD_OFFSET,
+};
+
+static const struct intel_ntb_xlat_reg skx_sec_xlat = {
+/*	.bar0_base		= SKX_EMBAR0_OFFSET, */
+	.bar2_limit		= SKX_IMBAR1XLMT_OFFSET,
+	.bar2_xlat		= SKX_IMBAR1XBASE_OFFSET,
+};
+
 /* operations for primary side of local ntb */
 static const struct ntb_dev_ops intel_ntb_ops = {
 	.mw_count		= intel_ntb_mw_count,
@@ -2284,6 +2908,31 @@ static const struct ntb_dev_ops intel_ntb_ops = {
 	.peer_spad_write	= intel_ntb_peer_spad_write,
 };
 
+static const struct ntb_dev_ops intel_ntb3_ops = {
+	.mw_count		= intel_ntb_mw_count,
+	.mw_get_range		= intel_ntb_mw_get_range,
+	.mw_set_trans		= intel_ntb3_mw_set_trans,
+	.link_is_up		= intel_ntb_link_is_up,
+	.link_enable		= intel_ntb3_link_enable,
+	.link_disable		= intel_ntb_link_disable,
+	.db_valid_mask		= intel_ntb_db_valid_mask,
+	.db_vector_count	= intel_ntb_db_vector_count,
+	.db_vector_mask		= intel_ntb_db_vector_mask,
+	.db_read		= intel_ntb3_db_read,
+	.db_clear		= intel_ntb3_db_clear,
+	.db_set_mask		= intel_ntb_db_set_mask,
+	.db_clear_mask		= intel_ntb_db_clear_mask,
+	.peer_db_addr		= intel_ntb_peer_db_addr,
+	.peer_db_set		= intel_ntb3_peer_db_set,
+	.spad_is_unsafe		= intel_ntb_spad_is_unsafe,
+	.spad_count		= intel_ntb_spad_count,
+	.spad_read		= intel_ntb_spad_read,
+	.spad_write		= intel_ntb_spad_write,
+	.peer_spad_addr		= intel_ntb_peer_spad_addr,
+	.peer_spad_read		= intel_ntb_peer_spad_read,
+	.peer_spad_write	= intel_ntb_peer_spad_write,
+};
+
 static const struct file_operations intel_ntb_debugfs_info = {
 	.owner = THIS_MODULE,
 	.open = simple_open,
@@ -2307,6 +2956,7 @@ static const struct pci_device_id intel_ntb_pci_tbl[] = {
 	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_IVT)},
 	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_HSX)},
 	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_BDX)},
+	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_SKX)},
 	{0}
 };
 MODULE_DEVICE_TABLE(pci, intel_ntb_pci_tbl);

drivers/ntb/hw/intel/ntb_hw_intel.h

@@ -70,6 +70,7 @@
 #define PCI_DEVICE_ID_INTEL_NTB_B2B_BDX	0x6F0D
 #define PCI_DEVICE_ID_INTEL_NTB_PS_BDX	0x6F0E
 #define PCI_DEVICE_ID_INTEL_NTB_SS_BDX	0x6F0F
+#define PCI_DEVICE_ID_INTEL_NTB_B2B_SKX	0x201C
 
 /* Intel Xeon hardware */
 
@@ -150,6 +151,51 @@
 #define XEON_DB_TOTAL_SHIFT		16
 #define XEON_SPAD_COUNT			16
 
+/* Intel Skylake Xeon hardware */
+#define SKX_IMBAR1SZ_OFFSET		0x00d1
+#define SKX_IMBAR2SZ_OFFSET		0x00d5
+#define SKX_EMBAR1SZ_OFFSET		0x00d3
+#define SKX_EMBAR2SZ_OFFSET		0x00d6
+#define SKX_DEVCTRL_OFFSET		0x0098
+#define SKX_DEVSTS_OFFSET		0x009a
+#define SKX_UNCERRSTS_OFFSET		0x014c
+#define SKX_CORERRSTS_OFFSET		0x0158
+#define SKX_LINK_STATUS_OFFSET		0x01a2
+
+#define SKX_NTBCNTL_OFFSET		0x0000
+#define SKX_IMBAR1XBASE_OFFSET		0x0010		/* SBAR2XLAT */
+#define SKX_IMBAR1XLMT_OFFSET		0x0018		/* SBAR2LMT */
+#define SKX_IMBAR2XBASE_OFFSET		0x0020		/* SBAR4XLAT */
+#define SKX_IMBAR2XLMT_OFFSET		0x0028		/* SBAR4LMT */
+#define SKX_IM_INT_STATUS_OFFSET	0x0040
+#define SKX_IM_INT_DISABLE_OFFSET	0x0048
+#define SKX_IM_SPAD_OFFSET		0x0080		/* SPAD */
+#define SKX_USMEMMISS_OFFSET		0x0070
+#define SKX_INTVEC_OFFSET		0x00d0
+#define SKX_IM_DOORBELL_OFFSET		0x0100		/* SDOORBELL0 */
+#define SKX_B2B_SPAD_OFFSET		0x0180		/* B2B SPAD */
+#define SKX_EMBAR0XBASE_OFFSET		0x4008		/* B2B_XLAT */
+#define SKX_EMBAR1XBASE_OFFSET		0x4010		/* PBAR2XLAT */
+#define SKX_EMBAR1XLMT_OFFSET		0x4018		/* PBAR2LMT */
+#define SKX_EMBAR2XBASE_OFFSET		0x4020		/* PBAR4XLAT */
+#define SKX_EMBAR2XLMT_OFFSET		0x4028		/* PBAR4LMT */
+#define SKX_EM_INT_STATUS_OFFSET	0x4040
+#define SKX_EM_INT_DISABLE_OFFSET	0x4048
+#define SKX_EM_SPAD_OFFSET		0x4080		/* remote SPAD */
+#define SKX_EM_DOORBELL_OFFSET		0x4100		/* PDOORBELL0 */
+#define SKX_SPCICMD_OFFSET		0x4504		/* SPCICMD */
+#define SKX_EMBAR0_OFFSET		0x4510		/* SBAR0BASE */
+#define SKX_EMBAR1_OFFSET		0x4518		/* SBAR23BASE */
+#define SKX_EMBAR2_OFFSET		0x4520		/* SBAR45BASE */
+
+#define SKX_DB_COUNT			32
+#define SKX_DB_LINK			32
+#define SKX_DB_LINK_BIT			BIT_ULL(SKX_DB_LINK)
+#define SKX_DB_MSIX_VECTOR_COUNT	33
+#define SKX_DB_MSIX_VECTOR_SHIFT	1
+#define SKX_DB_TOTAL_SHIFT		33
+#define SKX_SPAD_COUNT			16
+
 /* Intel Atom hardware */
 
 #define ATOM_SBAR2XLAT_OFFSET		0x0008
@@ -240,6 +286,7 @@
 #define NTB_HWERR_SDOORBELL_LOCKUP	BIT_ULL(0)
 #define NTB_HWERR_SB01BASE_LOCKUP	BIT_ULL(1)
 #define NTB_HWERR_B2BDOORBELL_BIT14	BIT_ULL(2)
+#define NTB_HWERR_MSIX_VECTOR32_BAD	BIT_ULL(3)
 
 /* flags to indicate unsafe api */
 #define NTB_UNSAFE_DB			BIT_ULL(0)
@@ -263,6 +310,7 @@ struct intel_ntb_reg {
 struct intel_ntb_alt_reg {
 	unsigned long			db_bell;
 	unsigned long			db_mask;
+	unsigned long			db_clear;
 	unsigned long			spad;
 };