drivers/infiniband/hw/mthca/mthca_reset.c - linux - Git at Google

 /*
  * 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;
 		goto put_dev;
 	}

 	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 free_hca;
 		}
 	}

 	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;
 			goto free_hca;
 		}

 		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 free_bh;
 			}
 		}
 		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 free_bh;
 		}
 	}

 	/* 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 free_bh;
 		}

 		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 free_bh;
 			}

 			if (v != 0xffffffff)
 				goto good;

 			msleep(100);
 		}

 		err = -ENODEV;
 		mthca_err(mdev, "PCI device did not come back after reset, "
 			  "aborting.\n");
 		goto free_bh;
 	}

 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 free_bh;
 		}
 		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 free_bh;
 		}
 		/*
 		 * 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 free_bh;
 			}
 		}

 		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 free_bh;
 		}
 	}

 	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 free_bh;
 		}
 	}

 	if (hca_pcie_cap) {
 		devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
 		if (pcie_capability_write_word(mdev->pdev, PCI_EXP_DEVCTL,
 					       devctl)) {
 			err = -ENODEV;
 			mthca_err(mdev, "Couldn't restore HCA PCI Express "
 				  "Device Control register, aborting.\n");
 			goto free_bh;
 		}
 		linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
 		if (pcie_capability_write_word(mdev->pdev, PCI_EXP_LNKCTL,
 					       linkctl)) {
 			err = -ENODEV;
 			mthca_err(mdev, "Couldn't restore HCA PCI Express "
 				  "Link control register, aborting.\n");
 			goto free_bh;
 		}
 	}

 	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 free_bh;
 		}
 	}

 	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");
 	}
 free_bh:
 	kfree(bridge_header);
 free_hca:
 	kfree(hca_header);
 put_dev:
 	pci_dev_put(bridge);
 	return err;
 }
	/*
	* 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;
	goto put_dev;
	}

	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 free_hca;
	}
	}

	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;
	goto free_hca;
	}

	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 free_bh;
	}
	}
	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 free_bh;
	}
	}

	/* 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 free_bh;
	}

	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 free_bh;
	}

	if (v != 0xffffffff)
	goto good;

	msleep(100);
	}

	err = -ENODEV;
	mthca_err(mdev, "PCI device did not come back after reset, "
	"aborting.\n");
	goto free_bh;
	}

	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 free_bh;
	}
	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 free_bh;
	}
	/*
	* 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 free_bh;
	}
	}

	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 free_bh;
	}
	}

	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 free_bh;
	}
	}

	if (hca_pcie_cap) {
	devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
	if (pcie_capability_write_word(mdev->pdev, PCI_EXP_DEVCTL,
	devctl)) {
	err = -ENODEV;
	mthca_err(mdev, "Couldn't restore HCA PCI Express "
	"Device Control register, aborting.\n");
	goto free_bh;
	}
	linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
	if (pcie_capability_write_word(mdev->pdev, PCI_EXP_LNKCTL,
	linkctl)) {
	err = -ENODEV;
	mthca_err(mdev, "Couldn't restore HCA PCI Express "
	"Link control register, aborting.\n");
	goto free_bh;
	}
	}

	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 free_bh;
	}
	}

	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");
	}
	free_bh:
	kfree(bridge_header);
	free_hca:
	kfree(hca_header);
	put_dev:
	pci_dev_put(bridge);
	return err;
	}