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-rw-r--r--drivers/infiniband/hw/hfi1/pcie.c1338
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;
+}