IB/hfi1: Move driver out of staging

The TODO list for the hfi1 driver was completed during 4.6. In addition
other objections raised (which are far beyond what was in the TODO list)
have been addressed as well. It is now time to remove the driver from
staging and into the drivers/infiniband sub-tree.

Reviewed-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 1338 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/hfi1/pcie.c b/drivers/infiniband/hw/hfi1/pcie.c
new file mode 100644
index 000000000000..0bac21e6a658
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/pcie.c
@@ -0,0 +1,1338 @@
+/*
+ * Copyright(c) 2015, 2016 Intel Corporation.
+ *
+ * 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
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * BSD LICENSE
+ *
+ * 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 copyright
+ *    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.
+ *
+ */
+
+#include <linux/pci.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/vmalloc.h>
+#include <linux/aer.h>
+#include <linux/module.h>
+
+#include "hfi.h"
+#include "chip_registers.h"
+#include "aspm.h"
+
+/* link speed vector for Gen3 speed - not in Linux headers */
+#define GEN1_SPEED_VECTOR 0x1
+#define GEN2_SPEED_VECTOR 0x2
+#define GEN3_SPEED_VECTOR 0x3
+
+/*
+ * This file contains PCIe utility routines.
+ */
+
+/*
+ * Code to adjust PCIe capabilities.
+ */
+static void tune_pcie_caps(struct hfi1_devdata *);
+
+/*
+ * Do all the common PCIe setup and initialization.
+ * devdata is not yet allocated, and is not allocated until after this
+ * routine returns success.  Therefore dd_dev_err() can't be used for error
+ * printing.
+ */
+int hfi1_pcie_init(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	int ret;
+
+	ret = pci_enable_device(pdev);
+	if (ret) {
+		/*
+		 * This can happen (in theory) iff:
+		 * We did a chip reset, and then failed to reprogram the
+		 * BAR, or the chip reset due to an internal error.  We then
+		 * unloaded the driver and reloaded it.
+		 *
+		 * Both reset cases set the BAR back to initial state.  For
+		 * the latter case, the AER sticky error bit at offset 0x718
+		 * should be set, but the Linux kernel doesn't yet know
+		 * about that, it appears.  If the original BAR was retained
+		 * in the kernel data structures, this may be OK.
+		 */
+		hfi1_early_err(&pdev->dev, "pci enable failed: error %d\n",
+			       -ret);
+		goto done;
+	}
+
+	ret = pci_request_regions(pdev, DRIVER_NAME);
+	if (ret) {
+		hfi1_early_err(&pdev->dev,
+			       "pci_request_regions fails: err %d\n", -ret);
+		goto bail;
+	}
+
+	ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
+	if (ret) {
+		/*
+		 * If the 64 bit setup fails, try 32 bit.  Some systems
+		 * do not setup 64 bit maps on systems with 2GB or less
+		 * memory installed.
+		 */
+		ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+		if (ret) {
+			hfi1_early_err(&pdev->dev,
+				       "Unable to set DMA mask: %d\n", ret);
+			goto bail;
+		}
+		ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+	} else {
+		ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
+	}
+	if (ret) {
+		hfi1_early_err(&pdev->dev,
+			       "Unable to set DMA consistent mask: %d\n", ret);
+		goto bail;
+	}
+
+	pci_set_master(pdev);
+	(void)pci_enable_pcie_error_reporting(pdev);
+	goto done;
+
+bail:
+	hfi1_pcie_cleanup(pdev);
+done:
+	return ret;
+}
+
+/*
+ * Clean what was done in hfi1_pcie_init()
+ */
+void hfi1_pcie_cleanup(struct pci_dev *pdev)
+{
+	pci_disable_device(pdev);
+	/*
+	 * Release regions should be called after the disable. OK to
+	 * call if request regions has not been called or failed.
+	 */
+	pci_release_regions(pdev);
+}
+
+/*
+ * Do remaining PCIe setup, once dd is allocated, and save away
+ * fields required to re-initialize after a chip reset, or for
+ * various other purposes
+ */
+int hfi1_pcie_ddinit(struct hfi1_devdata *dd, struct pci_dev *pdev,
+		     const struct pci_device_id *ent)
+{
+	unsigned long len;
+	resource_size_t addr;
+
+	dd->pcidev = pdev;
+	pci_set_drvdata(pdev, dd);
+
+	addr = pci_resource_start(pdev, 0);
+	len = pci_resource_len(pdev, 0);
+
+	/*
+	 * The TXE PIO buffers are at the tail end of the chip space.
+	 * Cut them off and map them separately.
+	 */
+
+	/* sanity check vs expectations */
+	if (len != TXE_PIO_SEND + TXE_PIO_SIZE) {
+		dd_dev_err(dd, "chip PIO range does not match\n");
+		return -EINVAL;
+	}
+
+	dd->kregbase = ioremap_nocache(addr, TXE_PIO_SEND);
+	if (!dd->kregbase)
+		return -ENOMEM;
+
+	dd->piobase = ioremap_wc(addr + TXE_PIO_SEND, TXE_PIO_SIZE);
+	if (!dd->piobase) {
+		iounmap(dd->kregbase);
+		return -ENOMEM;
+	}
+
+	dd->flags |= HFI1_PRESENT;	/* now register routines work */
+
+	dd->kregend = dd->kregbase + TXE_PIO_SEND;
+	dd->physaddr = addr;        /* used for io_remap, etc. */
+
+	/*
+	 * Re-map the chip's RcvArray as write-combining to allow us
+	 * to write an entire cacheline worth of entries in one shot.
+	 * If this re-map fails, just continue - the RcvArray programming
+	 * function will handle both cases.
+	 */
+	dd->chip_rcv_array_count = read_csr(dd, RCV_ARRAY_CNT);
+	dd->rcvarray_wc = ioremap_wc(addr + RCV_ARRAY,
+				     dd->chip_rcv_array_count * 8);
+	dd_dev_info(dd, "WC Remapped RcvArray: %p\n", dd->rcvarray_wc);
+	/*
+	 * Save BARs and command to rewrite after device reset.
+	 */
+	dd->pcibar0 = addr;
+	dd->pcibar1 = addr >> 32;
+	pci_read_config_dword(dd->pcidev, PCI_ROM_ADDRESS, &dd->pci_rom);
+	pci_read_config_word(dd->pcidev, PCI_COMMAND, &dd->pci_command);
+	pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL, &dd->pcie_devctl);
+	pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL, &dd->pcie_lnkctl);
+	pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL2,
+				  &dd->pcie_devctl2);
+	pci_read_config_dword(dd->pcidev, PCI_CFG_MSIX0, &dd->pci_msix0);
+	pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE1, &dd->pci_lnkctl3);
+	pci_read_config_dword(dd->pcidev, PCIE_CFG_TPH2, &dd->pci_tph2);
+
+	return 0;
+}
+
+/*
+ * Do PCIe cleanup related to dd, after chip-specific cleanup, etc.  Just prior
+ * to releasing the dd memory.
+ * Void because all of the core pcie cleanup functions are void.
+ */
+void hfi1_pcie_ddcleanup(struct hfi1_devdata *dd)
+{
+	u64 __iomem *base = (void __iomem *)dd->kregbase;
+
+	dd->flags &= ~HFI1_PRESENT;
+	dd->kregbase = NULL;
+	iounmap(base);
+	if (dd->rcvarray_wc)
+		iounmap(dd->rcvarray_wc);
+	if (dd->piobase)
+		iounmap(dd->piobase);
+}
+
+/*
+ * Do a Function Level Reset (FLR) on the device.
+ * Based on static function drivers/pci/pci.c:pcie_flr().
+ */
+void hfi1_pcie_flr(struct hfi1_devdata *dd)
+{
+	int i;
+	u16 status;
+
+	/* no need to check for the capability - we know the device has it */
+
+	/* wait for Transaction Pending bit to clear, at most a few ms */
+	for (i = 0; i < 4; i++) {
+		if (i)
+			msleep((1 << (i - 1)) * 100);
+
+		pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVSTA, &status);
+		if (!(status & PCI_EXP_DEVSTA_TRPND))
+			goto clear;
+	}
+
+	dd_dev_err(dd, "Transaction Pending bit is not clearing, proceeding with reset anyway\n");
+
+clear:
+	pcie_capability_set_word(dd->pcidev, PCI_EXP_DEVCTL,
+				 PCI_EXP_DEVCTL_BCR_FLR);
+	/* PCIe spec requires the function to be back within 100ms */
+	msleep(100);
+}
+
+static void msix_setup(struct hfi1_devdata *dd, int pos, u32 *msixcnt,
+		       struct hfi1_msix_entry *hfi1_msix_entry)
+{
+	int ret;
+	int nvec = *msixcnt;
+	struct msix_entry *msix_entry;
+	int i;
+
+	/*
+	 * We can't pass hfi1_msix_entry array to msix_setup
+	 * so use a dummy msix_entry array and copy the allocated
+	 * irq back to the hfi1_msix_entry array.
+	 */
+	msix_entry = kmalloc_array(nvec, sizeof(*msix_entry), GFP_KERNEL);
+	if (!msix_entry) {
+		ret = -ENOMEM;
+		goto do_intx;
+	}
+
+	for (i = 0; i < nvec; i++)
+		msix_entry[i] = hfi1_msix_entry[i].msix;
+
+	ret = pci_enable_msix_range(dd->pcidev, msix_entry, 1, nvec);
+	if (ret < 0)
+		goto free_msix_entry;
+	nvec = ret;
+
+	for (i = 0; i < nvec; i++)
+		hfi1_msix_entry[i].msix = msix_entry[i];
+
+	kfree(msix_entry);
+	*msixcnt = nvec;
+	return;
+
+free_msix_entry:
+	kfree(msix_entry);
+
+do_intx:
+	dd_dev_err(dd, "pci_enable_msix_range %d vectors failed: %d, falling back to INTx\n",
+		   nvec, ret);
+	*msixcnt = 0;
+	hfi1_enable_intx(dd->pcidev);
+}
+
+/* return the PCIe link speed from the given link status */
+static u32 extract_speed(u16 linkstat)
+{
+	u32 speed;
+
+	switch (linkstat & PCI_EXP_LNKSTA_CLS) {
+	default: /* not defined, assume Gen1 */
+	case PCI_EXP_LNKSTA_CLS_2_5GB:
+		speed = 2500; /* Gen 1, 2.5GHz */
+		break;
+	case PCI_EXP_LNKSTA_CLS_5_0GB:
+		speed = 5000; /* Gen 2, 5GHz */
+		break;
+	case GEN3_SPEED_VECTOR:
+		speed = 8000; /* Gen 3, 8GHz */
+		break;
+	}
+	return speed;
+}
+
+/* return the PCIe link speed from the given link status */
+static u32 extract_width(u16 linkstat)
+{
+	return (linkstat & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT;
+}
+
+/* read the link status and set dd->{lbus_width,lbus_speed,lbus_info} */
+static void update_lbus_info(struct hfi1_devdata *dd)
+{
+	u16 linkstat;
+
+	pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKSTA, &linkstat);
+	dd->lbus_width = extract_width(linkstat);
+	dd->lbus_speed = extract_speed(linkstat);
+	snprintf(dd->lbus_info, sizeof(dd->lbus_info),
+		 "PCIe,%uMHz,x%u", dd->lbus_speed, dd->lbus_width);
+}
+
+/*
+ * Read in the current PCIe link width and speed.  Find if the link is
+ * Gen3 capable.
+ */
+int pcie_speeds(struct hfi1_devdata *dd)
+{
+	u32 linkcap;
+	struct pci_dev *parent = dd->pcidev->bus->self;
+
+	if (!pci_is_pcie(dd->pcidev)) {
+		dd_dev_err(dd, "Can't find PCI Express capability!\n");
+		return -EINVAL;
+	}
+
+	/* find if our max speed is Gen3 and parent supports Gen3 speeds */
+	dd->link_gen3_capable = 1;
+
+	pcie_capability_read_dword(dd->pcidev, PCI_EXP_LNKCAP, &linkcap);
+	if ((linkcap & PCI_EXP_LNKCAP_SLS) != GEN3_SPEED_VECTOR) {
+		dd_dev_info(dd,
+			    "This HFI is not Gen3 capable, max speed 0x%x, need 0x3\n",
+			    linkcap & PCI_EXP_LNKCAP_SLS);
+		dd->link_gen3_capable = 0;
+	}
+
+	/*
+	 * bus->max_bus_speed is set from the bridge's linkcap Max Link Speed
+	 */
+	if (parent && dd->pcidev->bus->max_bus_speed != PCIE_SPEED_8_0GT) {
+		dd_dev_info(dd, "Parent PCIe bridge does not support Gen3\n");
+		dd->link_gen3_capable = 0;
+	}
+
+	/* obtain the link width and current speed */
+	update_lbus_info(dd);
+
+	dd_dev_info(dd, "%s\n", dd->lbus_info);
+
+	return 0;
+}
+
+/*
+ * Returns in *nent:
+ *	- actual number of interrupts allocated
+ *	- 0 if fell back to INTx.
+ */
+void request_msix(struct hfi1_devdata *dd, u32 *nent,
+		  struct hfi1_msix_entry *entry)
+{
+	int pos;
+
+	pos = dd->pcidev->msix_cap;
+	if (*nent && pos) {
+		msix_setup(dd, pos, nent, entry);
+		/* did it, either MSI-X or INTx */
+	} else {
+		*nent = 0;
+		hfi1_enable_intx(dd->pcidev);
+	}
+
+	tune_pcie_caps(dd);
+}
+
+void hfi1_enable_intx(struct pci_dev *pdev)
+{
+	/* first, turn on INTx */
+	pci_intx(pdev, 1);
+	/* then turn off MSI-X */
+	pci_disable_msix(pdev);
+}
+
+/* restore command and BARs after a reset has wiped them out */
+void restore_pci_variables(struct hfi1_devdata *dd)
+{
+	pci_write_config_word(dd->pcidev, PCI_COMMAND, dd->pci_command);
+	pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0, dd->pcibar0);
+	pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1, dd->pcibar1);
+	pci_write_config_dword(dd->pcidev, PCI_ROM_ADDRESS, dd->pci_rom);
+	pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL, dd->pcie_devctl);
+	pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL, dd->pcie_lnkctl);
+	pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL2,
+				   dd->pcie_devctl2);
+	pci_write_config_dword(dd->pcidev, PCI_CFG_MSIX0, dd->pci_msix0);
+	pci_write_config_dword(dd->pcidev, PCIE_CFG_SPCIE1, dd->pci_lnkctl3);
+	pci_write_config_dword(dd->pcidev, PCIE_CFG_TPH2, dd->pci_tph2);
+}
+
+/*
+ * BIOS may not set PCIe bus-utilization parameters for best performance.
+ * Check and optionally adjust them to maximize our throughput.
+ */
+static int hfi1_pcie_caps;
+module_param_named(pcie_caps, hfi1_pcie_caps, int, S_IRUGO);
+MODULE_PARM_DESC(pcie_caps, "Max PCIe tuning: Payload (0..3), ReadReq (4..7)");
+
+uint aspm_mode = ASPM_MODE_DISABLED;
+module_param_named(aspm, aspm_mode, uint, S_IRUGO);
+MODULE_PARM_DESC(aspm, "PCIe ASPM: 0: disable, 1: enable, 2: dynamic");
+
+static void tune_pcie_caps(struct hfi1_devdata *dd)
+{
+	struct pci_dev *parent;
+	u16 rc_mpss, rc_mps, ep_mpss, ep_mps;
+	u16 rc_mrrs, ep_mrrs, max_mrrs, ectl;
+
+	/*
+	 * Turn on extended tags in DevCtl in case the BIOS has turned it off
+	 * to improve WFR SDMA bandwidth
+	 */
+	pcie_capability_read_word(dd->pcidev, PCI_EXP_DEVCTL, &ectl);
+	if (!(ectl & PCI_EXP_DEVCTL_EXT_TAG)) {
+		dd_dev_info(dd, "Enabling PCIe extended tags\n");
+		ectl |= PCI_EXP_DEVCTL_EXT_TAG;
+		pcie_capability_write_word(dd->pcidev, PCI_EXP_DEVCTL, ectl);
+	}
+	/* Find out supported and configured values for parent (root) */
+	parent = dd->pcidev->bus->self;
+	/*
+	 * The driver cannot perform the tuning if it does not have
+	 * access to the upstream component.
+	 */
+	if (!parent)
+		return;
+	if (!pci_is_root_bus(parent->bus)) {
+		dd_dev_info(dd, "Parent not root\n");
+		return;
+	}
+
+	if (!pci_is_pcie(parent) || !pci_is_pcie(dd->pcidev))
+		return;
+	rc_mpss = parent->pcie_mpss;
+	rc_mps = ffs(pcie_get_mps(parent)) - 8;
+	/* Find out supported and configured values for endpoint (us) */
+	ep_mpss = dd->pcidev->pcie_mpss;
+	ep_mps = ffs(pcie_get_mps(dd->pcidev)) - 8;
+
+	/* Find max payload supported by root, endpoint */
+	if (rc_mpss > ep_mpss)
+		rc_mpss = ep_mpss;
+
+	/* If Supported greater than limit in module param, limit it */
+	if (rc_mpss > (hfi1_pcie_caps & 7))
+		rc_mpss = hfi1_pcie_caps & 7;
+	/* If less than (allowed, supported), bump root payload */
+	if (rc_mpss > rc_mps) {
+		rc_mps = rc_mpss;
+		pcie_set_mps(parent, 128 << rc_mps);
+	}
+	/* If less than (allowed, supported), bump endpoint payload */
+	if (rc_mpss > ep_mps) {
+		ep_mps = rc_mpss;
+		pcie_set_mps(dd->pcidev, 128 << ep_mps);
+	}
+
+	/*
+	 * Now the Read Request size.
+	 * No field for max supported, but PCIe spec limits it to 4096,
+	 * which is code '5' (log2(4096) - 7)
+	 */
+	max_mrrs = 5;
+	if (max_mrrs > ((hfi1_pcie_caps >> 4) & 7))
+		max_mrrs = (hfi1_pcie_caps >> 4) & 7;
+
+	max_mrrs = 128 << max_mrrs;
+	rc_mrrs = pcie_get_readrq(parent);
+	ep_mrrs = pcie_get_readrq(dd->pcidev);
+
+	if (max_mrrs > rc_mrrs) {
+		rc_mrrs = max_mrrs;
+		pcie_set_readrq(parent, rc_mrrs);
+	}
+	if (max_mrrs > ep_mrrs) {
+		ep_mrrs = max_mrrs;
+		pcie_set_readrq(dd->pcidev, ep_mrrs);
+	}
+}
+
+/* End of PCIe capability tuning */
+
+/*
+ * From here through hfi1_pci_err_handler definition is invoked via
+ * PCI error infrastructure, registered via pci
+ */
+static pci_ers_result_t
+pci_error_detected(struct pci_dev *pdev, pci_channel_state_t state)
+{
+	struct hfi1_devdata *dd = pci_get_drvdata(pdev);
+	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
+
+	switch (state) {
+	case pci_channel_io_normal:
+		dd_dev_info(dd, "State Normal, ignoring\n");
+		break;
+
+	case pci_channel_io_frozen:
+		dd_dev_info(dd, "State Frozen, requesting reset\n");
+		pci_disable_device(pdev);
+		ret = PCI_ERS_RESULT_NEED_RESET;
+		break;
+
+	case pci_channel_io_perm_failure:
+		if (dd) {
+			dd_dev_info(dd, "State Permanent Failure, disabling\n");
+			/* no more register accesses! */
+			dd->flags &= ~HFI1_PRESENT;
+			hfi1_disable_after_error(dd);
+		}
+		 /* else early, or other problem */
+		ret =  PCI_ERS_RESULT_DISCONNECT;
+		break;
+
+	default: /* shouldn't happen */
+		dd_dev_info(dd, "HFI1 PCI errors detected (state %d)\n",
+			    state);
+		break;
+	}
+	return ret;
+}
+
+static pci_ers_result_t
+pci_mmio_enabled(struct pci_dev *pdev)
+{
+	u64 words = 0U;
+	struct hfi1_devdata *dd = pci_get_drvdata(pdev);
+	pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
+
+	if (dd && dd->pport) {
+		words = read_port_cntr(dd->pport, C_RX_WORDS, CNTR_INVALID_VL);
+		if (words == ~0ULL)
+			ret = PCI_ERS_RESULT_NEED_RESET;
+		dd_dev_info(dd,
+			    "HFI1 mmio_enabled function called, read wordscntr %Lx, returning %d\n",
+			    words, ret);
+	}
+	return  ret;
+}
+
+static pci_ers_result_t
+pci_slot_reset(struct pci_dev *pdev)
+{
+	struct hfi1_devdata *dd = pci_get_drvdata(pdev);
+
+	dd_dev_info(dd, "HFI1 slot_reset function called, ignored\n");
+	return PCI_ERS_RESULT_CAN_RECOVER;
+}
+
+static pci_ers_result_t
+pci_link_reset(struct pci_dev *pdev)
+{
+	struct hfi1_devdata *dd = pci_get_drvdata(pdev);
+
+	dd_dev_info(dd, "HFI1 link_reset function called, ignored\n");
+	return PCI_ERS_RESULT_CAN_RECOVER;
+}
+
+static void
+pci_resume(struct pci_dev *pdev)
+{
+	struct hfi1_devdata *dd = pci_get_drvdata(pdev);
+
+	dd_dev_info(dd, "HFI1 resume function called\n");
+	pci_cleanup_aer_uncorrect_error_status(pdev);
+	/*
+	 * Running jobs will fail, since it's asynchronous
+	 * unlike sysfs-requested reset.   Better than
+	 * doing nothing.
+	 */
+	hfi1_init(dd, 1); /* same as re-init after reset */
+}
+
+const struct pci_error_handlers hfi1_pci_err_handler = {
+	.error_detected = pci_error_detected,
+	.mmio_enabled = pci_mmio_enabled,
+	.link_reset = pci_link_reset,
+	.slot_reset = pci_slot_reset,
+	.resume = pci_resume,
+};
+
+/*============================================================================*/
+/* PCIe Gen3 support */
+
+/*
+ * This code is separated out because it is expected to be removed in the
+ * final shipping product.  If not, then it will be revisited and items
+ * will be moved to more standard locations.
+ */
+
+/* ASIC_PCI_SD_HOST_STATUS.FW_DNLD_STS field values */
+#define DL_STATUS_HFI0 0x1	/* hfi0 firmware download complete */
+#define DL_STATUS_HFI1 0x2	/* hfi1 firmware download complete */
+#define DL_STATUS_BOTH 0x3	/* hfi0 and hfi1 firmware download complete */
+
+/* ASIC_PCI_SD_HOST_STATUS.FW_DNLD_ERR field values */
+#define DL_ERR_NONE		0x0	/* no error */
+#define DL_ERR_SWAP_PARITY	0x1	/* parity error in SerDes interrupt */
+					/*   or response data */
+#define DL_ERR_DISABLED	0x2	/* hfi disabled */
+#define DL_ERR_SECURITY	0x3	/* security check failed */
+#define DL_ERR_SBUS		0x4	/* SBus status error */
+#define DL_ERR_XFR_PARITY	0x5	/* parity error during ROM transfer*/
+
+/* gasket block secondary bus reset delay */
+#define SBR_DELAY_US 200000	/* 200ms */
+
+/* mask for PCIe capability register lnkctl2 target link speed */
+#define LNKCTL2_TARGET_LINK_SPEED_MASK 0xf
+
+static uint pcie_target = 3;
+module_param(pcie_target, uint, S_IRUGO);
+MODULE_PARM_DESC(pcie_target, "PCIe target speed (0 skip, 1-3 Gen1-3)");
+
+static uint pcie_force;
+module_param(pcie_force, uint, S_IRUGO);
+MODULE_PARM_DESC(pcie_force, "Force driver to do a PCIe firmware download even if already at target speed");
+
+static uint pcie_retry = 5;
+module_param(pcie_retry, uint, S_IRUGO);
+MODULE_PARM_DESC(pcie_retry, "Driver will try this many times to reach requested speed");
+
+#define UNSET_PSET 255
+#define DEFAULT_DISCRETE_PSET 2	/* discrete HFI */
+#define DEFAULT_MCP_PSET 4	/* MCP HFI */
+static uint pcie_pset = UNSET_PSET;
+module_param(pcie_pset, uint, S_IRUGO);
+MODULE_PARM_DESC(pcie_pset, "PCIe Eq Pset value to use, range is 0-10");
+
+/* equalization columns */
+#define PREC 0
+#define ATTN 1
+#define POST 2
+
+/* discrete silicon preliminary equalization values */
+static const u8 discrete_preliminary_eq[11][3] = {
+	/* prec   attn   post */
+	{  0x00,  0x00,  0x12 },	/* p0 */
+	{  0x00,  0x00,  0x0c },	/* p1 */
+	{  0x00,  0x00,  0x0f },	/* p2 */
+	{  0x00,  0x00,  0x09 },	/* p3 */
+	{  0x00,  0x00,  0x00 },	/* p4 */
+	{  0x06,  0x00,  0x00 },	/* p5 */
+	{  0x09,  0x00,  0x00 },	/* p6 */
+	{  0x06,  0x00,  0x0f },	/* p7 */
+	{  0x09,  0x00,  0x09 },	/* p8 */
+	{  0x0c,  0x00,  0x00 },	/* p9 */
+	{  0x00,  0x00,  0x18 },	/* p10 */
+};
+
+/* integrated silicon preliminary equalization values */
+static const u8 integrated_preliminary_eq[11][3] = {
+	/* prec   attn   post */
+	{  0x00,  0x1e,  0x07 },	/* p0 */
+	{  0x00,  0x1e,  0x05 },	/* p1 */
+	{  0x00,  0x1e,  0x06 },	/* p2 */
+	{  0x00,  0x1e,  0x04 },	/* p3 */
+	{  0x00,  0x1e,  0x00 },	/* p4 */
+	{  0x03,  0x1e,  0x00 },	/* p5 */
+	{  0x04,  0x1e,  0x00 },	/* p6 */
+	{  0x03,  0x1e,  0x06 },	/* p7 */
+	{  0x03,  0x1e,  0x04 },	/* p8 */
+	{  0x05,  0x1e,  0x00 },	/* p9 */
+	{  0x00,  0x1e,  0x0a },	/* p10 */
+};
+
+/* helper to format the value to write to hardware */
+#define eq_value(pre, curr, post) \
+	((((u32)(pre)) << \
+			PCIE_CFG_REG_PL102_GEN3_EQ_PRE_CURSOR_PSET_SHIFT) \
+	| (((u32)(curr)) << PCIE_CFG_REG_PL102_GEN3_EQ_CURSOR_PSET_SHIFT) \
+	| (((u32)(post)) << \
+		PCIE_CFG_REG_PL102_GEN3_EQ_POST_CURSOR_PSET_SHIFT))
+
+/*
+ * Load the given EQ preset table into the PCIe hardware.
+ */
+static int load_eq_table(struct hfi1_devdata *dd, const u8 eq[11][3], u8 fs,
+			 u8 div)
+{
+	struct pci_dev *pdev = dd->pcidev;
+	u32 hit_error = 0;
+	u32 violation;
+	u32 i;
+	u8 c_minus1, c0, c_plus1;
+
+	for (i = 0; i < 11; i++) {
+		/* set index */
+		pci_write_config_dword(pdev, PCIE_CFG_REG_PL103, i);
+		/* write the value */
+		c_minus1 = eq[i][PREC] / div;
+		c0 = fs - (eq[i][PREC] / div) - (eq[i][POST] / div);
+		c_plus1 = eq[i][POST] / div;
+		pci_write_config_dword(pdev, PCIE_CFG_REG_PL102,
+				       eq_value(c_minus1, c0, c_plus1));
+		/* check if these coefficients violate EQ rules */
+		pci_read_config_dword(dd->pcidev, PCIE_CFG_REG_PL105,
+				      &violation);
+		if (violation
+		    & PCIE_CFG_REG_PL105_GEN3_EQ_VIOLATE_COEF_RULES_SMASK){
+			if (hit_error == 0) {
+				dd_dev_err(dd,
+					   "Gen3 EQ Table Coefficient rule violations\n");
+				dd_dev_err(dd, "         prec   attn   post\n");
+			}
+			dd_dev_err(dd, "   p%02d:   %02x     %02x     %02x\n",
+				   i, (u32)eq[i][0], (u32)eq[i][1],
+				   (u32)eq[i][2]);
+			dd_dev_err(dd, "            %02x     %02x     %02x\n",
+				   (u32)c_minus1, (u32)c0, (u32)c_plus1);
+			hit_error = 1;
+		}
+	}
+	if (hit_error)
+		return -EINVAL;
+	return 0;
+}
+
+/*
+ * Steps to be done after the PCIe firmware is downloaded and
+ * before the SBR for the Pcie Gen3.
+ * The SBus resource is already being held.
+ */
+static void pcie_post_steps(struct hfi1_devdata *dd)
+{
+	int i;
+
+	set_sbus_fast_mode(dd);
+	/*
+	 * Write to the PCIe PCSes to set the G3_LOCKED_NEXT bits to 1.
+	 * This avoids a spurious framing error that can otherwise be
+	 * generated by the MAC layer.
+	 *
+	 * Use individual addresses since no broadcast is set up.
+	 */
+	for (i = 0; i < NUM_PCIE_SERDES; i++) {
+		sbus_request(dd, pcie_pcs_addrs[dd->hfi1_id][i],
+			     0x03, WRITE_SBUS_RECEIVER, 0x00022132);
+	}
+
+	clear_sbus_fast_mode(dd);
+}
+
+/*
+ * Trigger a secondary bus reset (SBR) on ourselves using our parent.
+ *
+ * Based on pci_parent_bus_reset() which is not exported by the
+ * kernel core.
+ */
+static int trigger_sbr(struct hfi1_devdata *dd)
+{
+	struct pci_dev *dev = dd->pcidev;
+	struct pci_dev *pdev;
+
+	/* need a parent */
+	if (!dev->bus->self) {
+		dd_dev_err(dd, "%s: no parent device\n", __func__);
+		return -ENOTTY;
+	}
+
+	/* should not be anyone else on the bus */
+	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
+		if (pdev != dev) {
+			dd_dev_err(dd,
+				   "%s: another device is on the same bus\n",
+				   __func__);
+			return -ENOTTY;
+		}
+
+	/*
+	 * A secondary bus reset (SBR) issues a hot reset to our device.
+	 * The following routine does a 1s wait after the reset is dropped
+	 * per PCI Trhfa (recovery time).  PCIe 3.0 section 6.6.1 -
+	 * Conventional Reset, paragraph 3, line 35 also says that a 1s
+	 * delay after a reset is required.  Per spec requirements,
+	 * the link is either working or not after that point.
+	 */
+	pci_reset_bridge_secondary_bus(dev->bus->self);
+
+	return 0;
+}
+
+/*
+ * Write the given gasket interrupt register.
+ */
+static void write_gasket_interrupt(struct hfi1_devdata *dd, int index,
+				   u16 code, u16 data)
+{
+	write_csr(dd, ASIC_PCIE_SD_INTRPT_LIST + (index * 8),
+		  (((u64)code << ASIC_PCIE_SD_INTRPT_LIST_INTRPT_CODE_SHIFT) |
+		   ((u64)data << ASIC_PCIE_SD_INTRPT_LIST_INTRPT_DATA_SHIFT)));
+}
+
+/*
+ * Tell the gasket logic how to react to the reset.
+ */
+static void arm_gasket_logic(struct hfi1_devdata *dd)
+{
+	u64 reg;
+
+	reg = (((u64)1 << dd->hfi1_id) <<
+	       ASIC_PCIE_SD_HOST_CMD_INTRPT_CMD_SHIFT) |
+	      ((u64)pcie_serdes_broadcast[dd->hfi1_id] <<
+	       ASIC_PCIE_SD_HOST_CMD_SBUS_RCVR_ADDR_SHIFT |
+	       ASIC_PCIE_SD_HOST_CMD_SBR_MODE_SMASK |
+	       ((u64)SBR_DELAY_US & ASIC_PCIE_SD_HOST_CMD_TIMER_MASK) <<
+	       ASIC_PCIE_SD_HOST_CMD_TIMER_SHIFT);
+	write_csr(dd, ASIC_PCIE_SD_HOST_CMD, reg);
+	/* read back to push the write */
+	read_csr(dd, ASIC_PCIE_SD_HOST_CMD);
+}
+
+/*
+ * CCE_PCIE_CTRL long name helpers
+ * We redefine these shorter macros to use in the code while leaving
+ * chip_registers.h to be autogenerated from the hardware spec.
+ */
+#define LANE_BUNDLE_MASK              CCE_PCIE_CTRL_PCIE_LANE_BUNDLE_MASK
+#define LANE_BUNDLE_SHIFT             CCE_PCIE_CTRL_PCIE_LANE_BUNDLE_SHIFT
+#define LANE_DELAY_MASK               CCE_PCIE_CTRL_PCIE_LANE_DELAY_MASK
+#define LANE_DELAY_SHIFT              CCE_PCIE_CTRL_PCIE_LANE_DELAY_SHIFT
+#define MARGIN_OVERWRITE_ENABLE_SHIFT CCE_PCIE_CTRL_XMT_MARGIN_OVERWRITE_ENABLE_SHIFT
+#define MARGIN_SHIFT                  CCE_PCIE_CTRL_XMT_MARGIN_SHIFT
+#define MARGIN_G1_G2_OVERWRITE_MASK   CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_OVERWRITE_ENABLE_MASK
+#define MARGIN_G1_G2_OVERWRITE_SHIFT  CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_OVERWRITE_ENABLE_SHIFT
+#define MARGIN_GEN1_GEN2_MASK         CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_MASK
+#define MARGIN_GEN1_GEN2_SHIFT        CCE_PCIE_CTRL_XMT_MARGIN_GEN1_GEN2_SHIFT
+
+ /*
+  * Write xmt_margin for full-swing (WFR-B) or half-swing (WFR-C).
+  */
+static void write_xmt_margin(struct hfi1_devdata *dd, const char *fname)
+{
+	u64 pcie_ctrl;
+	u64 xmt_margin;
+	u64 xmt_margin_oe;
+	u64 lane_delay;
+	u64 lane_bundle;
+
+	pcie_ctrl = read_csr(dd, CCE_PCIE_CTRL);
+
+	/*
+	 * For Discrete, use full-swing.
+	 *  - PCIe TX defaults to full-swing.
+	 *    Leave this register as default.
+	 * For Integrated, use half-swing
+	 *  - Copy xmt_margin and xmt_margin_oe
+	 *    from Gen1/Gen2 to Gen3.
+	 */
+	if (dd->pcidev->device == PCI_DEVICE_ID_INTEL1) { /* integrated */
+		/* extract initial fields */
+		xmt_margin = (pcie_ctrl >> MARGIN_GEN1_GEN2_SHIFT)
+			      & MARGIN_GEN1_GEN2_MASK;
+		xmt_margin_oe = (pcie_ctrl >> MARGIN_G1_G2_OVERWRITE_SHIFT)
+				 & MARGIN_G1_G2_OVERWRITE_MASK;
+		lane_delay = (pcie_ctrl >> LANE_DELAY_SHIFT) & LANE_DELAY_MASK;
+		lane_bundle = (pcie_ctrl >> LANE_BUNDLE_SHIFT)
+			       & LANE_BUNDLE_MASK;
+
+		/*
+		 * For A0, EFUSE values are not set.  Override with the
+		 * correct values.
+		 */
+		if (is_ax(dd)) {
+			/*
+			 * xmt_margin and OverwiteEnabel should be the
+			 * same for Gen1/Gen2 and Gen3
+			 */
+			xmt_margin = 0x5;
+			xmt_margin_oe = 0x1;
+			lane_delay = 0xF; /* Delay 240ns. */
+			lane_bundle = 0x0; /* Set to 1 lane. */
+		}
+
+		/* overwrite existing values */
+		pcie_ctrl = (xmt_margin << MARGIN_GEN1_GEN2_SHIFT)
+			| (xmt_margin_oe << MARGIN_G1_G2_OVERWRITE_SHIFT)
+			| (xmt_margin << MARGIN_SHIFT)
+			| (xmt_margin_oe << MARGIN_OVERWRITE_ENABLE_SHIFT)
+			| (lane_delay << LANE_DELAY_SHIFT)
+			| (lane_bundle << LANE_BUNDLE_SHIFT);
+
+		write_csr(dd, CCE_PCIE_CTRL, pcie_ctrl);
+	}
+
+	dd_dev_dbg(dd, "%s: program XMT margin, CcePcieCtrl 0x%llx\n",
+		   fname, pcie_ctrl);
+}
+
+/*
+ * Do all the steps needed to transition the PCIe link to Gen3 speed.
+ */
+int do_pcie_gen3_transition(struct hfi1_devdata *dd)
+{
+	struct pci_dev *parent = dd->pcidev->bus->self;
+	u64 fw_ctrl;
+	u64 reg, therm;
+	u32 reg32, fs, lf;
+	u32 status, err;
+	int ret;
+	int do_retry, retry_count = 0;
+	uint default_pset;
+	u16 target_vector, target_speed;
+	u16 lnkctl2, vendor;
+	u8 div;
+	const u8 (*eq)[3];
+	int return_error = 0;
+
+	/* PCIe Gen3 is for the ASIC only */
+	if (dd->icode != ICODE_RTL_SILICON)
+		return 0;
+
+	if (pcie_target == 1) {			/* target Gen1 */
+		target_vector = GEN1_SPEED_VECTOR;
+		target_speed = 2500;
+	} else if (pcie_target == 2) {		/* target Gen2 */
+		target_vector = GEN2_SPEED_VECTOR;
+		target_speed = 5000;
+	} else if (pcie_target == 3) {		/* target Gen3 */
+		target_vector = GEN3_SPEED_VECTOR;
+		target_speed = 8000;
+	} else {
+		/* off or invalid target - skip */
+		dd_dev_info(dd, "%s: Skipping PCIe transition\n", __func__);
+		return 0;
+	}
+
+	/* if already at target speed, done (unless forced) */
+	if (dd->lbus_speed == target_speed) {
+		dd_dev_info(dd, "%s: PCIe already at gen%d, %s\n", __func__,
+			    pcie_target,
+			    pcie_force ? "re-doing anyway" : "skipping");
+		if (!pcie_force)
+			return 0;
+	}
+
+	/*
+	 * The driver cannot do the transition if it has no access to the
+	 * upstream component
+	 */
+	if (!parent) {
+		dd_dev_info(dd, "%s: No upstream, Can't do gen3 transition\n",
+			    __func__);
+		return 0;
+	}
+
+	/*
+	 * Do the Gen3 transition.  Steps are those of the PCIe Gen3
+	 * recipe.
+	 */
+
+	/* step 1: pcie link working in gen1/gen2 */
+
+	/* step 2: if either side is not capable of Gen3, done */
+	if (pcie_target == 3 && !dd->link_gen3_capable) {
+		dd_dev_err(dd, "The PCIe link is not Gen3 capable\n");
+		ret = -ENOSYS;
+		goto done_no_mutex;
+	}
+
+	/* hold the SBus resource across the firmware download and SBR */
+	ret = acquire_chip_resource(dd, CR_SBUS, SBUS_TIMEOUT);
+	if (ret) {
+		dd_dev_err(dd, "%s: unable to acquire SBus resource\n",
+			   __func__);
+		return ret;
+	}
+
+	/* make sure thermal polling is not causing interrupts */
+	therm = read_csr(dd, ASIC_CFG_THERM_POLL_EN);
+	if (therm) {
+		write_csr(dd, ASIC_CFG_THERM_POLL_EN, 0x0);
+		msleep(100);
+		dd_dev_info(dd, "%s: Disabled therm polling\n",
+			    __func__);
+	}
+
+retry:
+	/* the SBus download will reset the spico for thermal */
+
+	/* step 3: download SBus Master firmware */
+	/* step 4: download PCIe Gen3 SerDes firmware */
+	dd_dev_info(dd, "%s: downloading firmware\n", __func__);
+	ret = load_pcie_firmware(dd);
+	if (ret) {
+		/* do not proceed if the firmware cannot be downloaded */
+		return_error = 1;
+		goto done;
+	}
+
+	/* step 5: set up device parameter settings */
+	dd_dev_info(dd, "%s: setting PCIe registers\n", __func__);
+
+	/*
+	 * PcieCfgSpcie1 - Link Control 3
+	 * Leave at reset value.  No need to set PerfEq - link equalization
+	 * will be performed automatically after the SBR when the target
+	 * speed is 8GT/s.
+	 */
+
+	/* clear all 16 per-lane error bits (PCIe: Lane Error Status) */
+	pci_write_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, 0xffff);
+
+	/* step 5a: Set Synopsys Port Logic registers */
+
+	/*
+	 * PcieCfgRegPl2 - Port Force Link
+	 *
+	 * Set the low power field to 0x10 to avoid unnecessary power
+	 * management messages.  All other fields are zero.
+	 */
+	reg32 = 0x10ul << PCIE_CFG_REG_PL2_LOW_PWR_ENT_CNT_SHIFT;
+	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL2, reg32);
+
+	/*
+	 * PcieCfgRegPl100 - Gen3 Control
+	 *
+	 * turn off PcieCfgRegPl100.Gen3ZRxDcNonCompl
+	 * turn on PcieCfgRegPl100.EqEieosCnt
+	 * Everything else zero.
+	 */
+	reg32 = PCIE_CFG_REG_PL100_EQ_EIEOS_CNT_SMASK;
+	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL100, reg32);
+
+	/*
+	 * PcieCfgRegPl101 - Gen3 EQ FS and LF
+	 * PcieCfgRegPl102 - Gen3 EQ Presets to Coefficients Mapping
+	 * PcieCfgRegPl103 - Gen3 EQ Preset Index
+	 * PcieCfgRegPl105 - Gen3 EQ Status
+	 *
+	 * Give initial EQ settings.
+	 */
+	if (dd->pcidev->device == PCI_DEVICE_ID_INTEL0) { /* discrete */
+		/* 1000mV, FS=24, LF = 8 */
+		fs = 24;
+		lf = 8;
+		div = 3;
+		eq = discrete_preliminary_eq;
+		default_pset = DEFAULT_DISCRETE_PSET;
+	} else {
+		/* 400mV, FS=29, LF = 9 */
+		fs = 29;
+		lf = 9;
+		div = 1;
+		eq = integrated_preliminary_eq;
+		default_pset = DEFAULT_MCP_PSET;
+	}
+	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL101,
+			       (fs <<
+				PCIE_CFG_REG_PL101_GEN3_EQ_LOCAL_FS_SHIFT) |
+			       (lf <<
+				PCIE_CFG_REG_PL101_GEN3_EQ_LOCAL_LF_SHIFT));
+	ret = load_eq_table(dd, eq, fs, div);
+	if (ret)
+		goto done;
+
+	/*
+	 * PcieCfgRegPl106 - Gen3 EQ Control
+	 *
+	 * Set Gen3EqPsetReqVec, leave other fields 0.
+	 */
+	if (pcie_pset == UNSET_PSET)
+		pcie_pset = default_pset;
+	if (pcie_pset > 10) {	/* valid range is 0-10, inclusive */
+		dd_dev_err(dd, "%s: Invalid Eq Pset %u, setting to %d\n",
+			   __func__, pcie_pset, default_pset);
+		pcie_pset = default_pset;
+	}
+	dd_dev_info(dd, "%s: using EQ Pset %u\n", __func__, pcie_pset);
+	pci_write_config_dword(dd->pcidev, PCIE_CFG_REG_PL106,
+			       ((1 << pcie_pset) <<
+			PCIE_CFG_REG_PL106_GEN3_EQ_PSET_REQ_VEC_SHIFT) |
+			PCIE_CFG_REG_PL106_GEN3_EQ_EVAL2MS_DISABLE_SMASK |
+			PCIE_CFG_REG_PL106_GEN3_EQ_PHASE23_EXIT_MODE_SMASK);
+
+	/*
+	 * step 5b: Do post firmware download steps via SBus
+	 */
+	dd_dev_info(dd, "%s: doing pcie post steps\n", __func__);
+	pcie_post_steps(dd);
+
+	/*
+	 * step 5c: Program gasket interrupts
+	 */
+	/* set the Rx Bit Rate to REFCLK ratio */
+	write_gasket_interrupt(dd, 0, 0x0006, 0x0050);
+	/* disable pCal for PCIe Gen3 RX equalization */
+	write_gasket_interrupt(dd, 1, 0x0026, 0x5b01);
+	/*
+	 * Enable iCal for PCIe Gen3 RX equalization, and set which
+	 * evaluation of RX_EQ_EVAL will launch the iCal procedure.
+	 */
+	write_gasket_interrupt(dd, 2, 0x0026, 0x5202);
+	/* terminate list */
+	write_gasket_interrupt(dd, 3, 0x0000, 0x0000);
+
+	/*
+	 * step 5d: program XMT margin
+	 */
+	write_xmt_margin(dd, __func__);
+
+	/*
+	 * step 5e: disable active state power management (ASPM). It
+	 * will be enabled if required later
+	 */
+	dd_dev_info(dd, "%s: clearing ASPM\n", __func__);
+	aspm_hw_disable_l1(dd);
+
+	/*
+	 * step 5f: clear DirectSpeedChange
+	 * PcieCfgRegPl67.DirectSpeedChange must be zero to prevent the
+	 * change in the speed target from starting before we are ready.
+	 * This field defaults to 0 and we are not changing it, so nothing
+	 * needs to be done.
+	 */
+
+	/* step 5g: Set target link speed */
+	/*
+	 * Set target link speed to be target on both device and parent.
+	 * On setting the parent: Some system BIOSs "helpfully" set the
+	 * parent target speed to Gen2 to match the ASIC's initial speed.
+	 * We can set the target Gen3 because we have already checked
+	 * that it is Gen3 capable earlier.
+	 */
+	dd_dev_info(dd, "%s: setting parent target link speed\n", __func__);
+	pcie_capability_read_word(parent, PCI_EXP_LNKCTL2, &lnkctl2);
+	dd_dev_info(dd, "%s: ..old link control2: 0x%x\n", __func__,
+		    (u32)lnkctl2);
+	/* only write to parent if target is not as high as ours */
+	if ((lnkctl2 & LNKCTL2_TARGET_LINK_SPEED_MASK) < target_vector) {
+		lnkctl2 &= ~LNKCTL2_TARGET_LINK_SPEED_MASK;
+		lnkctl2 |= target_vector;
+		dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__,
+			    (u32)lnkctl2);
+		pcie_capability_write_word(parent, PCI_EXP_LNKCTL2, lnkctl2);
+	} else {
+		dd_dev_info(dd, "%s: ..target speed is OK\n", __func__);
+	}
+
+	dd_dev_info(dd, "%s: setting target link speed\n", __func__);
+	pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL2, &lnkctl2);
+	dd_dev_info(dd, "%s: ..old link control2: 0x%x\n", __func__,
+		    (u32)lnkctl2);
+	lnkctl2 &= ~LNKCTL2_TARGET_LINK_SPEED_MASK;
+	lnkctl2 |= target_vector;
+	dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__,
+		    (u32)lnkctl2);
+	pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL2, lnkctl2);
+
+	/* step 5h: arm gasket logic */
+	/* hold DC in reset across the SBR */
+	write_csr(dd, CCE_DC_CTRL, CCE_DC_CTRL_DC_RESET_SMASK);
+	(void)read_csr(dd, CCE_DC_CTRL); /* DC reset hold */
+	/* save firmware control across the SBR */
+	fw_ctrl = read_csr(dd, MISC_CFG_FW_CTRL);
+
+	dd_dev_info(dd, "%s: arming gasket logic\n", __func__);
+	arm_gasket_logic(dd);
+
+	/*
+	 * step 6: quiesce PCIe link
+	 * The chip has already been reset, so there will be no traffic
+	 * from the chip.  Linux has no easy way to enforce that it will
+	 * not try to access the device, so we just need to hope it doesn't
+	 * do it while we are doing the reset.
+	 */
+
+	/*
+	 * step 7: initiate the secondary bus reset (SBR)
+	 * step 8: hardware brings the links back up
+	 * step 9: wait for link speed transition to be complete
+	 */
+	dd_dev_info(dd, "%s: calling trigger_sbr\n", __func__);
+	ret = trigger_sbr(dd);
+	if (ret)
+		goto done;
+
+	/* step 10: decide what to do next */
+
+	/* check if we can read PCI space */
+	ret = pci_read_config_word(dd->pcidev, PCI_VENDOR_ID, &vendor);
+	if (ret) {
+		dd_dev_info(dd,
+			    "%s: read of VendorID failed after SBR, err %d\n",
+			    __func__, ret);
+		return_error = 1;
+		goto done;
+	}
+	if (vendor == 0xffff) {
+		dd_dev_info(dd, "%s: VendorID is all 1s after SBR\n", __func__);
+		return_error = 1;
+		ret = -EIO;
+		goto done;
+	}
+
+	/* restore PCI space registers we know were reset */
+	dd_dev_info(dd, "%s: calling restore_pci_variables\n", __func__);
+	restore_pci_variables(dd);
+	/* restore firmware control */
+	write_csr(dd, MISC_CFG_FW_CTRL, fw_ctrl);
+
+	/*
+	 * Check the gasket block status.
+	 *
+	 * This is the first CSR read after the SBR.  If the read returns
+	 * all 1s (fails), the link did not make it back.
+	 *
+	 * Once we're sure we can read and write, clear the DC reset after
+	 * the SBR.  Then check for any per-lane errors. Then look over
+	 * the status.
+	 */
+	reg = read_csr(dd, ASIC_PCIE_SD_HOST_STATUS);
+	dd_dev_info(dd, "%s: gasket block status: 0x%llx\n", __func__, reg);
+	if (reg == ~0ull) {	/* PCIe read failed/timeout */
+		dd_dev_err(dd, "SBR failed - unable to read from device\n");
+		return_error = 1;
+		ret = -ENOSYS;
+		goto done;
+	}
+
+	/* clear the DC reset */
+	write_csr(dd, CCE_DC_CTRL, 0);
+
+	/* Set the LED off */
+	setextled(dd, 0);
+
+	/* check for any per-lane errors */
+	pci_read_config_dword(dd->pcidev, PCIE_CFG_SPCIE2, &reg32);
+	dd_dev_info(dd, "%s: per-lane errors: 0x%x\n", __func__, reg32);
+
+	/* extract status, look for our HFI */
+	status = (reg >> ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_STS_SHIFT)
+			& ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_STS_MASK;
+	if ((status & (1 << dd->hfi1_id)) == 0) {
+		dd_dev_err(dd,
+			   "%s: gasket status 0x%x, expecting 0x%x\n",
+			   __func__, status, 1 << dd->hfi1_id);
+		ret = -EIO;
+		goto done;
+	}
+
+	/* extract error */
+	err = (reg >> ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_ERR_SHIFT)
+		& ASIC_PCIE_SD_HOST_STATUS_FW_DNLD_ERR_MASK;
+	if (err) {
+		dd_dev_err(dd, "%s: gasket error %d\n", __func__, err);
+		ret = -EIO;
+		goto done;
+	}
+
+	/* update our link information cache */
+	update_lbus_info(dd);
+	dd_dev_info(dd, "%s: new speed and width: %s\n", __func__,
+		    dd->lbus_info);
+
+	if (dd->lbus_speed != target_speed) { /* not target */
+		/* maybe retry */
+		do_retry = retry_count < pcie_retry;
+		dd_dev_err(dd, "PCIe link speed did not switch to Gen%d%s\n",
+			   pcie_target, do_retry ? ", retrying" : "");
+		retry_count++;
+		if (do_retry) {
+			msleep(100); /* allow time to settle */
+			goto retry;
+		}
+		ret = -EIO;
+	}
+
+done:
+	if (therm) {
+		write_csr(dd, ASIC_CFG_THERM_POLL_EN, 0x1);
+		msleep(100);
+		dd_dev_info(dd, "%s: Re-enable therm polling\n",
+			    __func__);
+	}
+	release_chip_resource(dd, CR_SBUS);
+done_no_mutex:
+	/* return no error if it is OK to be at current speed */
+	if (ret && !return_error) {
+		dd_dev_err(dd, "Proceeding at current speed PCIe speed\n");
+		ret = 0;
+	}
+
+	dd_dev_info(dd, "%s: done\n", __func__);
+	return ret;
+}