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awilliam
GitHub Repository: awilliam/linux-vfio
Path: blob/master/drivers/mca/mca-bus.c
15109 views
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/* -*- mode: c; c-basic-offset: 8 -*- */
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/*
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* MCA bus support functions for sysfs.
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*
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* (C) 2002 James Bottomley <[email protected]>
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*
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**-----------------------------------------------------------------------------
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**
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** This program is free software; you can redistribute it and/or modify
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** it under the terms of the GNU General Public License as published by
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** the Free Software Foundation; either version 2 of the License, or
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** (at your option) any later version.
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**
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** This program is distributed in the hope that it will be useful,
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** but WITHOUT ANY WARRANTY; without even the implied warranty of
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** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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** GNU General Public License for more details.
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**
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** You should have received a copy of the GNU General Public License
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** along with this program; if not, write to the Free Software
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** Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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**
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**-----------------------------------------------------------------------------
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*/
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#include <linux/kernel.h>
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#include <linux/device.h>
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#include <linux/mca.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/slab.h>
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/* Very few machines have more than one MCA bus. However, there are
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* those that do (Voyager 35xx/5xxx), so we do it this way for future
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* expansion. None that I know have more than 2 */
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static struct mca_bus *mca_root_busses[MAX_MCA_BUSSES];
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#define MCA_DEVINFO(i,s) { .pos = i, .name = s }
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struct mca_device_info {
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short pos_id; /* the 2 byte pos id for this card */
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char name[50];
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};
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static int mca_bus_match (struct device *dev, struct device_driver *drv)
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{
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struct mca_device *mca_dev = to_mca_device (dev);
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struct mca_driver *mca_drv = to_mca_driver (drv);
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const unsigned short *mca_ids = mca_drv->id_table;
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int i = 0;
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if (mca_ids) {
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for(i = 0; mca_ids[i]; i++) {
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if (mca_ids[i] == mca_dev->pos_id) {
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mca_dev->index = i;
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return 1;
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}
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}
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}
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/* If the integrated id is present, treat it as though it were an
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* additional id in the id_table (it can't be because by definition,
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* integrated id's overflow a short */
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if (mca_drv->integrated_id && mca_dev->pos_id ==
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mca_drv->integrated_id) {
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mca_dev->index = i;
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return 1;
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}
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return 0;
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}
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struct bus_type mca_bus_type = {
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.name = "MCA",
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.match = mca_bus_match,
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};
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EXPORT_SYMBOL (mca_bus_type);
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static ssize_t mca_show_pos_id(struct device *dev, struct device_attribute *attr, char *buf)
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{
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/* four digits, \n and trailing \0 */
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struct mca_device *mca_dev = to_mca_device(dev);
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int len;
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if(mca_dev->pos_id < MCA_DUMMY_POS_START)
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len = sprintf(buf, "%04x\n", mca_dev->pos_id);
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else
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len = sprintf(buf, "none\n");
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return len;
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}
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static ssize_t mca_show_pos(struct device *dev, struct device_attribute *attr, char *buf)
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{
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/* enough for 8 two byte hex chars plus space and new line */
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int j, len=0;
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struct mca_device *mca_dev = to_mca_device(dev);
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for(j=0; j<8; j++)
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len += sprintf(buf+len, "%02x ", mca_dev->pos[j]);
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/* change last trailing space to new line */
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buf[len-1] = '\n';
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return len;
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}
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static DEVICE_ATTR(id, S_IRUGO, mca_show_pos_id, NULL);
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static DEVICE_ATTR(pos, S_IRUGO, mca_show_pos, NULL);
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int __init mca_register_device(int bus, struct mca_device *mca_dev)
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{
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struct mca_bus *mca_bus = mca_root_busses[bus];
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int rc;
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mca_dev->dev.parent = &mca_bus->dev;
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mca_dev->dev.bus = &mca_bus_type;
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dev_set_name(&mca_dev->dev, "%02d:%02X", bus, mca_dev->slot);
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mca_dev->dma_mask = mca_bus->default_dma_mask;
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mca_dev->dev.dma_mask = &mca_dev->dma_mask;
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mca_dev->dev.coherent_dma_mask = mca_dev->dma_mask;
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rc = device_register(&mca_dev->dev);
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if (rc)
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goto err_out;
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rc = device_create_file(&mca_dev->dev, &dev_attr_id);
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if (rc) goto err_out_devreg;
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rc = device_create_file(&mca_dev->dev, &dev_attr_pos);
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if (rc) goto err_out_id;
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return 1;
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err_out_id:
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device_remove_file(&mca_dev->dev, &dev_attr_id);
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err_out_devreg:
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device_unregister(&mca_dev->dev);
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err_out:
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return 0;
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}
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/* */
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struct mca_bus * __devinit mca_attach_bus(int bus)
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{
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struct mca_bus *mca_bus;
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if (unlikely(mca_root_busses[bus] != NULL)) {
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/* This should never happen, but just in case */
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printk(KERN_EMERG "MCA tried to add already existing bus %d\n",
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bus);
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dump_stack();
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return NULL;
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}
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mca_bus = kzalloc(sizeof(struct mca_bus), GFP_KERNEL);
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if (!mca_bus)
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return NULL;
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dev_set_name(&mca_bus->dev, "mca%d", bus);
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sprintf(mca_bus->name,"Host %s MCA Bridge", bus ? "Secondary" : "Primary");
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if (device_register(&mca_bus->dev)) {
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kfree(mca_bus);
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return NULL;
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}
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mca_root_busses[bus] = mca_bus;
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return mca_bus;
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}
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int __init mca_system_init (void)
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{
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return bus_register(&mca_bus_type);
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}
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