linux/drivers/infiniband/hw/mthca/mthca_reset.c
Jon Mason 9b89925c0d IB/mthca: Remove unnecessary read of PCI_CAP_ID_EXP
The PCIE capability offset is saved during PCI bus walking.  It will
remove an unnecessary search in the PCI configuration space if this
value is referenced instead of reacquiring it.  Also, pci_is_pcie is a
better way of determining if the device is PCIE or not (as it uses the
same saved PCIE capability offset).

Signed-off-by: Jon Mason <jdmason@kudzu.us>
Signed-off-by: Roland Dreier <roland@purestorage.com>
2011-07-18 12:01:22 -07:00

289 lines
7.5 KiB
C

/*
* Copyright (c) 2004 Topspin Communications. 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/errno.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include "mthca_dev.h"
#include "mthca_cmd.h"
int mthca_reset(struct mthca_dev *mdev)
{
int i;
int err = 0;
u32 *hca_header = NULL;
u32 *bridge_header = NULL;
struct pci_dev *bridge = NULL;
int bridge_pcix_cap = 0;
int hca_pcie_cap = 0;
int hca_pcix_cap = 0;
u16 devctl;
u16 linkctl;
#define MTHCA_RESET_OFFSET 0xf0010
#define MTHCA_RESET_VALUE swab32(1)
/*
* Reset the chip. This is somewhat ugly because we have to
* save off the PCI header before reset and then restore it
* after the chip reboots. We skip config space offsets 22
* and 23 since those have a special meaning.
*
* To make matters worse, for Tavor (PCI-X HCA) we have to
* find the associated bridge device and save off its PCI
* header as well.
*/
if (!(mdev->mthca_flags & MTHCA_FLAG_PCIE)) {
/* Look for the bridge -- its device ID will be 2 more
than HCA's device ID. */
while ((bridge = pci_get_device(mdev->pdev->vendor,
mdev->pdev->device + 2,
bridge)) != NULL) {
if (bridge->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
bridge->subordinate == mdev->pdev->bus) {
mthca_dbg(mdev, "Found bridge: %s\n",
pci_name(bridge));
break;
}
}
if (!bridge) {
/*
* Didn't find a bridge for a Tavor device --
* assume we're in no-bridge mode and hope for
* the best.
*/
mthca_warn(mdev, "No bridge found for %s\n",
pci_name(mdev->pdev));
}
}
/* For Arbel do we need to save off the full 4K PCI Express header?? */
hca_header = kmalloc(256, GFP_KERNEL);
if (!hca_header) {
err = -ENOMEM;
mthca_err(mdev, "Couldn't allocate memory to save HCA "
"PCI header, aborting.\n");
goto out;
}
for (i = 0; i < 64; ++i) {
if (i == 22 || i == 23)
continue;
if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
err = -ENODEV;
mthca_err(mdev, "Couldn't save HCA "
"PCI header, aborting.\n");
goto out;
}
}
hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
hca_pcie_cap = pci_pcie_cap(mdev->pdev);
if (bridge) {
bridge_header = kmalloc(256, GFP_KERNEL);
if (!bridge_header) {
err = -ENOMEM;
mthca_err(mdev, "Couldn't allocate memory to save HCA "
"bridge PCI header, aborting.\n");
goto out;
}
for (i = 0; i < 64; ++i) {
if (i == 22 || i == 23)
continue;
if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
err = -ENODEV;
mthca_err(mdev, "Couldn't save HCA bridge "
"PCI header, aborting.\n");
goto out;
}
}
bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
if (!bridge_pcix_cap) {
err = -ENODEV;
mthca_err(mdev, "Couldn't locate HCA bridge "
"PCI-X capability, aborting.\n");
goto out;
}
}
/* actually hit reset */
{
void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
MTHCA_RESET_OFFSET, 4);
if (!reset) {
err = -ENOMEM;
mthca_err(mdev, "Couldn't map HCA reset register, "
"aborting.\n");
goto out;
}
writel(MTHCA_RESET_VALUE, reset);
iounmap(reset);
}
/* Docs say to wait one second before accessing device */
msleep(1000);
/* Now wait for PCI device to start responding again */
{
u32 v;
int c = 0;
for (c = 0; c < 100; ++c) {
if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
err = -ENODEV;
mthca_err(mdev, "Couldn't access HCA after reset, "
"aborting.\n");
goto out;
}
if (v != 0xffffffff)
goto good;
msleep(100);
}
err = -ENODEV;
mthca_err(mdev, "PCI device did not come back after reset, "
"aborting.\n");
goto out;
}
good:
/* Now restore the PCI headers */
if (bridge) {
if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
err = -ENODEV;
mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
"split transaction control, aborting.\n");
goto out;
}
if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
err = -ENODEV;
mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
"split transaction control, aborting.\n");
goto out;
}
/*
* Bridge control register is at 0x3e, so we'll
* naturally restore it last in this loop.
*/
for (i = 0; i < 16; ++i) {
if (i * 4 == PCI_COMMAND)
continue;
if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
err = -ENODEV;
mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
"aborting.\n", i);
goto out;
}
}
if (pci_write_config_dword(bridge, PCI_COMMAND,
bridge_header[PCI_COMMAND / 4])) {
err = -ENODEV;
mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
"aborting.\n");
goto out;
}
}
if (hca_pcix_cap) {
if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
hca_header[hca_pcix_cap / 4])) {
err = -ENODEV;
mthca_err(mdev, "Couldn't restore HCA PCI-X "
"command register, aborting.\n");
goto out;
}
}
if (hca_pcie_cap) {
devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
devctl)) {
err = -ENODEV;
mthca_err(mdev, "Couldn't restore HCA PCI Express "
"Device Control register, aborting.\n");
goto out;
}
linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
linkctl)) {
err = -ENODEV;
mthca_err(mdev, "Couldn't restore HCA PCI Express "
"Link control register, aborting.\n");
goto out;
}
}
for (i = 0; i < 16; ++i) {
if (i * 4 == PCI_COMMAND)
continue;
if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
err = -ENODEV;
mthca_err(mdev, "Couldn't restore HCA reg %x, "
"aborting.\n", i);
goto out;
}
}
if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
hca_header[PCI_COMMAND / 4])) {
err = -ENODEV;
mthca_err(mdev, "Couldn't restore HCA COMMAND, "
"aborting.\n");
goto out;
}
out:
if (bridge)
pci_dev_put(bridge);
kfree(bridge_header);
kfree(hca_header);
return err;
}