[PATCH v2 27/51] IB/qib: Add qib_pcie.c

Ralph Campbell
2009-12-03T19:05:27Z

creates the qib_pcie.c file.

Signed-off-by: Ralph Campbell <ralph.campbell-h88ZbnxC6KDQT0dZR+AlfA@public.gmane.org>
---

drivers/infiniband/hw/qib/qib_pcie.c | 810 ++++++++++++++++++++++++++++++++++
1 files changed, 810 insertions(+), 0 deletions(-)
create mode 100644 drivers/infiniband/hw/qib/qib_pcie.c

diff --git a/drivers/infiniband/hw/qib/qib_pcie.c b/drivers/infiniband/hw/qib/qib_pcie.c
new file mode 100644
index 0000000..714cad4
--- /dev/null
+++ b/drivers/infiniband/hw/qib/qib_pcie.c
@@ -0,0 +1,810 @@
+/*
+ * Copyright (c) 2008, 2009 QLogic Corporation. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * 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.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/pci.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/vmalloc.h>
+#include <linux/aer.h>
+
+#include "qib.h"
+
+/*
+ * This file contains PCIe utility routines that are common to the
+ * various QLogic InfiniPath adapters
+ */
+
+/*
+ * Code to adjust PCIe capabilities.
+ * To minimize the change footprint, we call it
+ * from qib_pcie_params, which every chip-specific
+ * file calls, even though this violates some
+ * expectations of harmlessness.
+ */
+static int qib_tune_pcie_caps(struct qib_devdata *);
+static int qib_tune_pcie_coalesce(struct qib_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 qib_dev_err() can't be used for error
+ * printing.
+ */
+int qib_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.
+ */
+ qib_early_err(&pdev->dev, "pci enable failed: error %d\n",
+ -ret);
+ goto done;
+ }
+
+ ret = pci_request_regions(pdev, QIB_DRV_NAME);
+ if (ret) {
+ qib_devinfo(pdev, "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) {
+ qib_devinfo(pdev, "Unable to set DMA mask: %d\n", ret);
+ goto bail;
+ }
+ qib_dbg("No 64bit DMA mask, used 32 bit mask\n");
+ 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)
+ qib_early_err(&pdev->dev,
+ "Unable to set DMA consistent mask: %d\n", ret);
+
+ pci_set_master(pdev);
+ ret = pci_enable_pcie_error_reporting(pdev);
+ if (ret)
+ qib_early_err(&pdev->dev,
+ "Unable to enable pcie error reporting: %d\n",
+ ret);
+ goto done;
+
+bail:
+ pci_disable_device(pdev);
+ pci_release_regions(pdev);
+done:
+ return ret;
+}
+
+/*
+ * 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 qib_pcie_ddinit(struct qib_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);
+ qib_cdbg(VERBOSE, "regbase (0) %llx len %ld vend %x/%x "
+ "driver_data %p\n", (unsigned long long)addr, len,
+ ent->vendor, ent->device, pci_get_drvdata(pdev));
+
+#if defined(__powerpc__)
+ /* There isn't a generic way to specify writethrough mappings */
+ dd->kregbase = __ioremap(addr, len, _PAGE_NO_CACHE | _PAGE_WRITETHRU);
+#else
+ dd->kregbase = ioremap_nocache(addr, len);
+#endif
+
+ if (!dd->kregbase) {
+ qib_dbg("Unable to map io addr %llx to kvirt, failing\n",
+ (unsigned long long)addr);
+ return -ENOMEM;
+ }
+
+ dd->kregend = (u64 __iomem *)((void __iomem *) dd->kregbase + len);
+ dd->physaddr = addr; /* used for io_remap, etc. */
+ /* for user mmap */
+ qib_cdbg(VERBOSE, "mapped io addr %llx to kregbase %p through %p\n",
+ (unsigned long long)addr, dd->kregbase, dd->kregend);
+
+ /*
+ * Save BARs to rewrite after device reset. Save all 64 bits of
+ * BAR, just in case.
+ */
+ dd->pcibar0 = addr;
+ dd->pcibar1 = addr >> 32;
+ dd->deviceid = ent->device; /* save for later use */
+ dd->vendorid = ent->vendor;
+
+ return 0;
+}
+
+/*
+ * Do PCIe cleanup, after chip-specific cleanup, etc. Just prior
+ * to releasing the dd memory.
+ * void because none of the core pcie cleanup returns are void
+ */
+void qib_pcie_ddcleanup(struct qib_devdata *dd)
+{
+ u64 __iomem *base = (void __iomem *) dd->kregbase;
+
+ qib_cdbg(VERBOSE, "Unmapping kregbase %p\n", dd->kregbase);
+ dd->kregbase = NULL;
+ iounmap(base);
+ if (dd->piobase) {
+ qib_cdbg(VERBOSE, "Unmapping piobase %p\n", dd->piobase);
+ iounmap(dd->piobase);
+ }
+ if (dd->userbase) {
+ qib_cdbg(VERBOSE, "Unmapping userbase %p\n", dd->userbase);
+ iounmap(dd->userbase);
+ }
+
+ qib_cdbg(VERBOSE, "calling pci_disable_device\n");
+ pci_disable_device(dd->pcidev);
+ pci_release_regions(dd->pcidev);
+
+ pci_set_drvdata(dd->pcidev, NULL);
+}
+
+static void qib_msix_setup(struct qib_devdata *dd, int pos, u32 *msixcnt,
+ struct msix_entry *msix_entry)
+{
+ int ret;
+ u32 tabsize = 0;
+ u16 msix_flags;
+
+ pci_read_config_word(dd->pcidev, pos + PCI_MSIX_FLAGS, &msix_flags);
+ tabsize = 1 + (msix_flags & PCI_MSIX_FLAGS_QSIZE);
+ if (tabsize > *msixcnt)
+ tabsize = *msixcnt;
+ ret = pci_enable_msix(dd->pcidev, msix_entry, tabsize);
+ if (ret > 0) {
+ qib_dbg("Couldn't get %d MSIx vectors, "
+ "trying to get %d\n", tabsize, ret);
+ tabsize = ret;
+ ret = pci_enable_msix(dd->pcidev, msix_entry, tabsize);
+ }
+ if (ret) {
+ qib_dev_err(dd, "pci_enable_msix %d vectors failed: %d, "
+ "falling back to INTx\n", tabsize, ret);
+ tabsize = 0;
+ }
+ *msixcnt = tabsize;
+
+ if (ret)
+ qib_enable_intx(dd->pcidev);
+
+}
+
+/**
+ * We save the msi lo and hi values, so we can restore them after
+ * chip reset (the kernel PCI infrastructure doesn't yet handle that
+ * correctly.
+ */
+static int qib_msi_setup(struct qib_devdata *dd, int pos)
+{
+ struct pci_dev *pdev = dd->pcidev;
+ u16 control;
+ int ret;
+
+ ret = pci_enable_msi(pdev);
+ if (ret)
+ qib_dev_err(dd, "pci_enable_msi failed: %d, "
+ "interrupts may not work\n", ret);
+ /* continue even if it fails, we may still be OK... */
+
+ pci_read_config_dword(pdev, pos + PCI_MSI_ADDRESS_LO,
+ &dd->msi_lo);
+ pci_read_config_dword(pdev, pos + PCI_MSI_ADDRESS_HI,
+ &dd->msi_hi);
+ pci_read_config_word(pdev, pos + PCI_MSI_FLAGS, &control);
+ /* now save the data (vector) info */
+ pci_read_config_word(pdev, pos + ((control & PCI_MSI_FLAGS_64BIT)
+ ? 12 : 8),
+ &dd->msi_data);
+ qib_cdbg(VERBOSE, "Read msi data 0x%x from config offset "
+ "0x%x, control=0x%x\n", dd->msi_data,
+ pos + ((control & PCI_MSI_FLAGS_64BIT) ? 12 : 8),
+ control);
+ return ret;
+}
+
+int qib_pcie_params(struct qib_devdata *dd, u32 minw, u32 *nent,
+ struct msix_entry *entry)
+{
+ u16 linkstat, speed;
+ int pos = 0, pose, ret = 1;
+
+ pose = pci_find_capability(dd->pcidev, PCI_CAP_ID_EXP);
+ if (!pose) {
+ qib_dev_err(dd, "Can't find PCI Express capability!\n");
+ /* set up something... */
+ dd->lbus_width = 1;
+ dd->lbus_speed = 2500; /* Gen1, 2.5GHz */
+ goto bail;
+ }
+
+ pos = pci_find_capability(dd->pcidev, PCI_CAP_ID_MSIX);
+ if (nent && *nent && pos) {
+ qib_msix_setup(dd, pos, nent, entry);
+ ret = 0; /* did it, either MSIx or INTx */
+ } else {
+ pos = pci_find_capability(dd->pcidev, PCI_CAP_ID_MSI);
+ if (pos)
+ ret = qib_msi_setup(dd, pos);
+ else
+ qib_dev_err(dd, "No PCI MSI or MSIx capability!\n");
+ }
+ if (!pos)
+ qib_enable_intx(dd->pcidev);
+
+ pci_read_config_word(dd->pcidev, pose + PCI_EXP_LNKSTA, &linkstat);
+ /*
+ * speed is bits 0-3, linkwidth is bits 4-8
+ * no defines for them in headers
+ */
+ speed = linkstat & 0xf;
+ linkstat >>= 4;
+ linkstat &= 0x1f;
+ dd->lbus_width = linkstat;
+
+ switch (speed) {
+ case 1:
+ dd->lbus_speed = 2500; /* Gen1, 2.5GHz */
+ break;
+ case 2:
+ dd->lbus_speed = 5000; /* Gen1, 5GHz */
+ break;
+ default: /* not defined, assume gen1 */
+ qib_dbg("PCIe unexpected link speed %u\n", speed);
+ dd->lbus_speed = 2500;
+ break;
+ }
+
+ /*
+ * Check against expected pcie width and complain if "wrong"
+ * on first initialization, not afterwards (i.e., reset).
+ */
+ if (minw && linkstat < minw)
+ qib_dev_err(dd,
+ "PCIe width %u (x%u HCA), performance reduced\n",
+ linkstat, minw);
+ else
+ qib_cdbg(VERBOSE, "PCIe speed %u width %u (x8 HCA)\n",
+ dd->lbus_speed, linkstat);
+
+ qib_tune_pcie_caps(dd);
+
+ qib_tune_pcie_coalesce(dd);
+
+bail:
+ /* fill in string, even on errors */
+ snprintf(dd->lbus_info, sizeof(dd->lbus_info),
+ "PCIe,%uMHz,x%u\n", dd->lbus_speed, dd->lbus_width);
+ return ret;
+}
+
+/*
+ * Setup pcie interrupt stuff again after a reset. I'd like to just call
+ * pci_enable_msi() again for msi, but when I do that,
+ * the MSI enable bit doesn't get set in the command word, and
+ * we switch to to a different interrupt vector, which is confusing,
+ * so I instead just do it all inline. Perhaps somehow can tie this
+ * into the PCIe hotplug support at some point
+ */
+int qib_reinit_intr(struct qib_devdata *dd)
+{
+ int pos;
+ u16 control;
+ int ret = 0;
+
+ /* If we aren't using MSI, don't restore it */
+ if (!dd->msi_lo)
+ goto bail;
+
+ pos = pci_find_capability(dd->pcidev, PCI_CAP_ID_MSI);
+ if (!pos) {
+ qib_dev_err(dd, "Can't find MSI capability, "
+ "can't restore MSI settings\n");
+ ret = 0;
+ /* nothing special for MSIx, just MSI */
+ goto bail;
+ }
+ qib_cdbg(VERBOSE, "Writing msi_lo 0x%x to config offset 0x%x\n",
+ dd->msi_lo, pos + PCI_MSI_ADDRESS_LO);
+ pci_write_config_dword(dd->pcidev, pos + PCI_MSI_ADDRESS_LO,
+ dd->msi_lo);
+ qib_cdbg(VERBOSE, "Writing msi_lo 0x%x to config offset 0x%x\n",
+ dd->msi_hi, pos + PCI_MSI_ADDRESS_HI);
+ pci_write_config_dword(dd->pcidev, pos + PCI_MSI_ADDRESS_HI,
+ dd->msi_hi);
+ pci_read_config_word(dd->pcidev, pos + PCI_MSI_FLAGS, &control);
+ if (!(control & PCI_MSI_FLAGS_ENABLE)) {
+ qib_cdbg(INIT, "MSI control at off %x was %x, "
+ "setting MSI enable (%x)\n", pos + PCI_MSI_FLAGS,
+ control, control | PCI_MSI_FLAGS_ENABLE);
+ control |= PCI_MSI_FLAGS_ENABLE;
+ pci_write_config_word(dd->pcidev, pos + PCI_MSI_FLAGS,
+ control);
+ }
+ /* now rewrite the data (vector) info */
+ pci_write_config_word(dd->pcidev, pos +
+ ((control & PCI_MSI_FLAGS_64BIT) ? 12 : 8),
+ dd->msi_data);
+ ret = 1;
+bail:
+ if (!ret && (dd->flags & QIB_HAS_INTX)) {
+ qib_cdbg(INIT, "Using INTx, MSI disabled or not configured\n");
+ qib_enable_intx(dd->pcidev);
+ ret = 1;
+ }
+
+ /* and now set the pci master bit again */
+ pci_set_master(dd->pcidev);
+
+ return ret;
+}
+
+/*
+ * Disable msi interrupt if enabled, and clear msi_lo.
+ * This is used primarily for the fallback to INTx, but
+ * is also used in reinit after reset, and during cleanup.
+ */
+void qib_nomsi(struct qib_devdata *dd)
+{
+ dd->msi_lo = 0;
+ qib_cdbg(INIT, "disable device MSI interrupts\n");
+ pci_disable_msi(dd->pcidev);
+}
+
+/*
+ * Same as qib_nosmi, but for MSIx.
+ */
+void qib_nomsix(struct qib_devdata *dd)
+{
+ qib_cdbg(INIT, "disable device MSIx interrupts\n");
+ pci_disable_msix(dd->pcidev);
+}
+
+/*
+ * Similar to pci_intx(pdev, 1), except that we make sure
+ * msi(x) is off.
+ */
+void qib_enable_intx(struct pci_dev *pdev)
+{
+ u16 cw, new;
+ int pos;
+
+ qib_cdbg(INIT, "Using INTx interrupts\n");
+
+ /* first, turn on INTx */
+ pci_read_config_word(pdev, PCI_COMMAND, &cw);
+ new = cw & ~PCI_COMMAND_INTX_DISABLE;
+ if (new != cw)
+ pci_write_config_word(pdev, PCI_COMMAND, new);
+
+ pos = pci_find_capability(pdev, PCI_CAP_ID_MSI);
+ if (pos) {
+ /* then turn off MSI */
+ pci_read_config_word(pdev, pos + PCI_MSI_FLAGS, &cw);
+ new = cw & ~PCI_MSI_FLAGS_ENABLE;
+ if (new != cw)
+ pci_write_config_word(pdev, pos + PCI_MSI_FLAGS, new);
+ }
+ pos = pci_find_capability(pdev, PCI_CAP_ID_MSIX);
+ if (pos) {
+ /* then turn off MSIx */
+ pci_read_config_word(pdev, pos + PCI_MSIX_FLAGS, &cw);
+ new = cw & ~PCI_MSIX_FLAGS_ENABLE;
+ if (new != cw)
+ pci_write_config_word(pdev, pos + PCI_MSIX_FLAGS, new);
+ }
+}
+
+/*
+ * These two routines are helper routines for the device reset code
+ * to move all the pcie code out of the chip-specific driver code.
+ */
+void qib_pcie_getcmd(struct qib_devdata *dd, u16 *cmd, u8 *iline, u8 *cline)
+{
+ pci_read_config_word(dd->pcidev, PCI_COMMAND, cmd);
+ pci_read_config_byte(dd->pcidev, PCI_INTERRUPT_LINE, iline);
+ pci_read_config_byte(dd->pcidev, PCI_CACHE_LINE_SIZE, cline);
+}
+
+void qib_pcie_reenable(struct qib_devdata *dd, u16 cmd, u8 iline, u8 cline)
+{
+ int r;
+ r = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_0,
+ dd->pcibar0);
+ if (r)
+ qib_dev_err(dd, "rewrite of BAR0 failed: %d\n", r);
+ r = pci_write_config_dword(dd->pcidev, PCI_BASE_ADDRESS_1,
+ dd->pcibar1);
+ if (r)
+ qib_dev_err(dd, "rewrite of BAR1 failed: %d\n", r);
+ /* now re-enable memory access, and restore cosmetic settings */
+ pci_write_config_word(dd->pcidev, PCI_COMMAND, cmd);
+ pci_write_config_byte(dd->pcidev, PCI_INTERRUPT_LINE, iline);
+ pci_write_config_byte(dd->pcidev, PCI_CACHE_LINE_SIZE, cline);
+ r = pci_enable_device(dd->pcidev);
+ if (r)
+ qib_dev_err(dd, "pci_enable_device failed after "
+ "reset: %d\n", r);
+}
+
+/* code to adjust PCIe capabilities. */
+
+static int fld2val(int wd, int mask)
+{
+ int lsbmask;
+
+ if (!mask)
+ return 0;
+ wd &= mask;
+ lsbmask = mask ^ (mask & (mask - 1));
+ wd /= lsbmask;
+ return wd;
+}
+
+static int val2fld(int wd, int mask)
+{
+ int lsbmask;
+
+ if (!mask)
+ return 0;
+ lsbmask = mask ^ (mask & (mask - 1));
+ wd *= lsbmask;
+ return wd;
+}
+
+static int qib_pcie_coalesce;
+module_param_named(pcie_coalesce, qib_pcie_coalesce, int, S_IRUGO);
+MODULE_PARM_DESC(pcie_coalesce, "tune PCIe colescing on some Intel chipsets");
+
+/*
+ * Enable PCIe completion and data coalescing, on Intel 5x00 and 7300
+ * chipsets. This is known to be unsafe for some revisions of some
+ * of these chipsets, with some BIOS settings, and enabling it on those
+ * systems may result in the system crashing, and/or data corruption.
+ */
+static int qib_tune_pcie_coalesce(struct qib_devdata *dd)
+{
+ int r;
+ struct pci_dev *parent;
+ int ppos;
+ u16 devid;
+ u32 mask, bits, val;
+
+ if (!qib_pcie_coalesce)
+ return 0;
+
+ /* Find out supported and configured values for parent (root) */
+ parent = dd->pcidev->bus->self;
+ if (parent->bus->parent) {
+ qib_devinfo(dd->pcidev, "Parent not root\n");
+ return 1;
+ }
+ ppos = pci_find_capability(parent, PCI_CAP_ID_EXP);
+ if (!ppos) {
+ qib_dbg("parent not PCIe root complex!?\n");
+ return 1;
+ }
+ if (parent->vendor != 0x8086) {
+ qib_cdbg(VERBOSE, "VendorID 0x%x isn't Intel, skip\n",
+ parent->vendor);
+ return 1;
+ }
+
+ /*
+ * - bit 12: Max_rdcmp_Imt_EN: need to set to 1
+ * - bit 11: COALESCE_FORCE: need to set to 0
+ * - bit 10: COALESCE_EN: need to set to 1
+ * (but limitations on some on some chipsets)
+ *
+ * On the Intel 5000, 5100, and 7300 chipsets, there is
+ * also: - bit 25:24: COALESCE_MODE, need to set to 0
+ */
+ devid = parent->device;
+ if (devid >= 0x25e2 && devid <= 0x25fa) {
+ u8 rev;
+
+ /* 5000 P/V/X/Z */
+ pci_read_config_byte(parent, PCI_REVISION_ID, &rev);
+ if (rev <= 0xb2) {
+ bits = 1U << 10;
+ qib_cdbg(INIT, "Old rev 5000* (0x%x), enable-only\n",
+ rev);
+ } else
+ bits = 7U << 10;
+ mask = (3U << 24) | (7U << 10);
+ } else if (devid >= 0x65e2 && devid <= 0x65fa) {
+ /* 5100 */
+ bits = 1U << 10;
+ mask = (3U << 24) | (7U << 10);
+ } else if (devid >= 0x4021 && devid <= 0x402e) {
+ /* 5400 */
+ bits = 7U << 10;
+ mask = 7U << 10;
+ } else if (devid >= 0x3604 && devid <= 0x360a) {
+ /* 7300 */
+ bits = 7U << 10;
+ mask = (3U << 24) | (7U << 10);
+ } else {
+ /* not one of the chipsets that we know about */
+ qib_cdbg(VERBOSE, "DeviceID 0x%x isn't one we know, skip\n",
+ devid);
+ return 1;
+ }
+ pci_read_config_dword(parent, 0x48, &val);
+ qib_cdbg(VERBOSE, "Read initial value 0x%x at 0x48, deviceid 0x%x\n",
+ val, devid);
+ val &= ~mask;
+ val |= bits;
+ r = pci_write_config_dword(parent, 0x48, val);
+ if (r)
+ qib_dev_err(dd, "Unable to update deviceid 0x%x to val 0x%x"
+ " for PCIe coalescing\n", devid, val);
+ else
+ qib_dbg("Updated deviceid 0x%x to val 0x%x"
+ " for PCIe coalescing\n", devid, val);
+ return 0;
+}
+
+/*
+ * BIOS may not set PCIe bus-utilization parameters for best performance.
+ * Check and optionally adjust them to maximize our throughput.
+ */
+static int qib_pcie_caps;
+module_param_named(pcie_caps, qib_pcie_caps, int, S_IRUGO);
+MODULE_PARM_DESC(pcie_caps, "Max PCIe tuning: Payload (4lsb), ReadReq (D4..7)");
+
+static int qib_tune_pcie_caps(struct qib_devdata *dd)
+{
+ int ret = 1; /* Assume the worst */
+ struct pci_dev *parent;
+ int ppos, epos;
+ u16 pcaps, pctl, ecaps, ectl;
+ int rc_sup, ep_sup;
+ int rc_cur, ep_cur;
+
+ /* Find out supported and configured values for parent (root) */
+ parent = dd->pcidev->bus->self;
+ if (parent->bus->parent) {
+ qib_devinfo(dd->pcidev, "Parent not root\n");
+ goto bail;
+ }
+ ppos = pci_find_capability(parent, PCI_CAP_ID_EXP);
+ if (ppos) {
+ pci_read_config_word(parent, ppos + PCI_EXP_DEVCAP, &pcaps);
+ pci_read_config_word(parent, ppos + PCI_EXP_DEVCTL, &pctl);
+ qib_cdbg(VERBOSE, "Root caps %04X, ctl %04X\n", pcaps, pctl);
+ } else
+ goto bail;
+ /* Find out supported and configured values for endpoint (us) */
+ epos = pci_find_capability(dd->pcidev, PCI_CAP_ID_EXP);
+ if (epos) {
+ pci_read_config_word(dd->pcidev, epos + PCI_EXP_DEVCAP, &ecaps);
+ pci_read_config_word(dd->pcidev, epos + PCI_EXP_DEVCTL, &ectl);
+ qib_cdbg(VERBOSE, "our caps %04X, ctl %04X\n", ecaps, ectl);
+ } else
+ goto bail;
+ ret = 0;
+ /* Find max payload supported by root, endpoint */
+ rc_sup = fld2val(pcaps, PCI_EXP_DEVCAP_PAYLOAD);
+ ep_sup = fld2val(ecaps, PCI_EXP_DEVCAP_PAYLOAD);
+ qib_cdbg(VERBOSE, "Root supports %d payload, we support %d\n",
+ (1U << (rc_sup + 7)), (1U << (ep_sup + 7)));
+ if (rc_sup > ep_sup)
+ rc_sup = ep_sup;
+
+ rc_cur = fld2val(pctl, PCI_EXP_DEVCTL_PAYLOAD);
+ ep_cur = fld2val(ectl, PCI_EXP_DEVCTL_PAYLOAD);
+ qib_cdbg(VERBOSE, "Root set to %d payload, we are %d\n",
+ (1U << (rc_cur + 7)), (1U << (ep_cur + 7)));
+
+ /* If Supported greater than limit in module param, limit it */
+ if (rc_sup > (qib_pcie_caps & 7))
+ rc_sup = qib_pcie_caps & 7;
+ /* If less than (allowed, supported), bump root payload */
+ if (rc_sup > rc_cur) {
+ rc_cur = rc_sup;
+ qib_cdbg(INIT, "Increase Root to %d Payload\n",
+ (1U << (rc_cur + 7)));
+ pctl = (pctl & ~PCI_EXP_DEVCTL_PAYLOAD) |
+ val2fld(rc_cur, PCI_EXP_DEVCTL_PAYLOAD);
+ pci_write_config_word(parent, ppos + PCI_EXP_DEVCTL, pctl);
+ }
+ /* If less than (allowed, supported), bump endpoint payload */
+ if (rc_sup > ep_cur) {
+ ep_cur = rc_sup;
+ qib_cdbg(INIT, "Increase Endpoint to %d Payload\n",
+ (1U << (ep_cur + 7)));
+ ectl = (ectl & ~PCI_EXP_DEVCTL_PAYLOAD) |
+ val2fld(ep_cur, PCI_EXP_DEVCTL_PAYLOAD);
+ pci_write_config_word(dd->pcidev, epos + PCI_EXP_DEVCTL, ectl);
+ }
+
+ /*
+ * Now the Read Request size.
+ * No field for max supported, but PCIe spec limits it to 4096,
+ * which is code '5' (log2(4096) - 7)
+ */
+ rc_sup = 5;
+ if (rc_sup > ((qib_pcie_caps >> 4) & 7))
+ rc_sup = (qib_pcie_caps >> 4) & 7;
+ rc_cur = fld2val(pctl, PCI_EXP_DEVCTL_READRQ);
+ ep_cur = fld2val(ectl, PCI_EXP_DEVCTL_READRQ);
+
+ qib_cdbg(VERBOSE, "Root set to %d rdreq, we are %d\n",
+ 1U << (rc_cur + 7), 1U << (ep_cur + 7));
+
+ if (rc_sup > rc_cur) {
+ rc_cur = rc_sup;
+ qib_cdbg(INIT, "Increase Root to %d RdReq\n",
+ (1U << (rc_cur + 7)));
+ pctl = (pctl & ~PCI_EXP_DEVCTL_READRQ) |
+ val2fld(rc_cur, PCI_EXP_DEVCTL_READRQ);
+ pci_write_config_word(parent, ppos + PCI_EXP_DEVCTL, pctl);
+ }
+ if (rc_sup > ep_cur) {
+ ep_cur = rc_sup;
+ qib_cdbg(INIT, "Increase Endpoint to %d RdReq\n",
+ (1U << (ep_cur + 7)));
+ ectl = (ectl & ~PCI_EXP_DEVCTL_READRQ) |
+ val2fld(ep_cur, PCI_EXP_DEVCTL_READRQ);
+ pci_write_config_word(dd->pcidev, epos + PCI_EXP_DEVCTL, ectl);
+ }
+bail:
+ return ret;
+}
+/* End of PCIe capability tuning */
+
+/*
+ * From here through qib_pci_err_handler definition is invoked via
+ * PCI error infrastructure, registered via pci
+ */
+static pci_ers_result_t
+qib_pci_error_detected(struct pci_dev *pdev, pci_channel_state_t state)
+{
+ struct qib_devdata *dd = pci_get_drvdata(pdev);
+ pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
+
+ switch (state) {
+ case pci_channel_io_normal:
+ qib_devinfo(pdev, "State Normal, ignoring\n");
+ break;
+
+ case pci_channel_io_frozen:
+ qib_devinfo(pdev, "State Frozen, requesting reset\n");
+ pci_disable_device(pdev);
+ ret = PCI_ERS_RESULT_NEED_RESET;
+ break;
+
+ case pci_channel_io_perm_failure:
+ qib_devinfo(pdev, "State Permanent Failure, disabling\n");
+ if (dd) {
+ /* no more register accesses! */
+ dd->flags &= ~QIB_PRESENT;
+ qib_disable_after_error(dd);
+ }
+ /* else early, or other problem */
+ ret = PCI_ERS_RESULT_DISCONNECT;
+ break;
+
+ default: /* shouldn't happen */
+ qib_devinfo(pdev, "QIB PCI errors detected (state %d)\n",
+ state);
+ break;
+ }
+ return ret;
+}
+
+static pci_ers_result_t
+qib_pci_mmio_enabled(struct pci_dev *pdev)
+{
+ u64 words = 0U;
+ struct qib_devdata *dd = pci_get_drvdata(pdev);
+ pci_ers_result_t ret = PCI_ERS_RESULT_RECOVERED;
+
+ if (dd && dd->pport) {
+ words = dd->f_portcntr(dd->pport, QIBPORTCNTR_WORDRCV);
+ if (words == ~0ULL)
+ ret = PCI_ERS_RESULT_NEED_RESET;
+ }
+ qib_devinfo(pdev, "QIB mmio_enabled function called, "
+ "read wordscntr %Lx, returning %d\n", words, ret);
+ return ret;
+}
+
+static pci_ers_result_t
+qib_pci_slot_reset(struct pci_dev *pdev)
+{
+ qib_devinfo(pdev, "QIB link_reset function called, ignored\n");
+ return PCI_ERS_RESULT_CAN_RECOVER;
+}
+
+static pci_ers_result_t
+qib_pci_link_reset(struct pci_dev *pdev)
+{
+ qib_devinfo(pdev, "QIB link_reset function called, ignored\n");
+ return PCI_ERS_RESULT_CAN_RECOVER;
+}
+
+static void
+qib_pci_resume(struct pci_dev *pdev)
+{
+ struct qib_devdata *dd = pci_get_drvdata(pdev);
+ qib_devinfo(pdev, "QIB 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.
+ */
+ qib_init(dd, 1); /* same as re-init after reset */
+}
+
+struct pci_error_handlers qib_pci_err_handler = {
+ .error_detected = qib_pci_error_detected,
+ .mmio_enabled = qib_pci_mmio_enabled,
+ .link_reset = qib_pci_link_reset,
+ .slot_reset = qib_pci_slot_reset,
+ .resume = qib_pci_resume,
+};