drivers/xen/platform-pci.c

   1 /******************************************************************************
   2  * platform-pci.c
   3  *
   4  * Xen platform PCI device driver
   5  * Copyright (c) 2005, Intel Corporation.
   6  * Copyright (c) 2007, XenSource Inc.
   7  * Copyright (c) 2010, Citrix
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms and conditions of the GNU General Public License,
  11  * version 2, as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope it will be useful, but WITHOUT
  14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  16  * more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along with
  19  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  20  * Place - Suite 330, Boston, MA 02111-1307 USA.
  21  *
  22  */
  23
  24
  25 #include <linux/interrupt.h>
  26 #include <linux/io.h>
  27 #include <linux/module.h>
  28 #include <linux/pci.h>
  29
  30 #include <xen/grant_table.h>
  31 #include <xen/xenbus.h>
  32 #include <xen/events.h>
  33 #include <xen/hvm.h>
  34
  35 #define DRV_NAME    "xen-platform-pci"
  36
  37 MODULE_AUTHOR("ssmith@xensource.com and stefano.stabellini@eu.citrix.com");
  38 MODULE_DESCRIPTION("Xen platform PCI device");
  39 MODULE_LICENSE("GPL");
  40
  41 static unsigned long platform_mmio;
  42 static unsigned long platform_mmio_alloc;
  43 static unsigned long platform_mmiolen;
  44
  45 unsigned long alloc_xen_mmio(unsigned long len)
  46 {
  47         unsigned long addr;
  48
  49         addr = platform_mmio + platform_mmio_alloc;
  50         platform_mmio_alloc += len;
  51         BUG_ON(platform_mmio_alloc > platform_mmiolen);
  52
  53         return addr;
  54 }
  55
  56 static uint64_t get_callback_via(struct pci_dev *pdev)
  57 {
  58         u8 pin;
  59         int irq;
  60
  61         irq = pdev->irq;
  62         if (irq < 16)
  63                 return irq; /* ISA IRQ */
  64
  65         pin = pdev->pin;
  66
  67         /* We don't know the GSI. Specify the PCI INTx line instead. */
  68         return ((uint64_t)0x01 << 56) | /* PCI INTx identifier */
  69                 ((uint64_t)pci_domain_nr(pdev->bus) << 32) |
  70                 ((uint64_t)pdev->bus->number << 16) |
  71                 ((uint64_t)(pdev->devfn & 0xff) << 8) |
  72                 ((uint64_t)(pin - 1) & 3);
  73 }
  74
  75 static irqreturn_t do_hvm_evtchn_intr(int irq, void *dev_id)
  76 {
  77         xen_hvm_evtchn_do_upcall();
  78         return IRQ_HANDLED;
  79 }
  80
  81 static int xen_allocate_irq(struct pci_dev *pdev)
  82 {
  83         return request_irq(pdev->irq, do_hvm_evtchn_intr,
  84                         IRQF_DISABLED | IRQF_NOBALANCING | IRQF_TRIGGER_RISING,
  85                         "xen-platform-pci", pdev);
  86 }
  87
  88 static int __devinit platform_pci_init(struct pci_dev *pdev,
  89                                        const struct pci_device_id *ent)
  90 {
  91         int i, ret;
  92         long ioaddr, iolen;
  93         long mmio_addr, mmio_len;
  94         uint64_t callback_via;
  95         unsigned int max_nr_gframes;
  96
  97         i = pci_enable_device(pdev);
  98         if (i)
  99                 return i;
 100
 101         ioaddr = pci_resource_start(pdev, 0);
 102         iolen = pci_resource_len(pdev, 0);
 103
 104         mmio_addr = pci_resource_start(pdev, 1);
 105         mmio_len = pci_resource_len(pdev, 1);
 106
 107         if (mmio_addr == 0 || ioaddr == 0) {
 108                 dev_err(&pdev->dev, "no resources found\n");
 109                 ret = -ENOENT;
 110                 goto pci_out;
 111         }
 112
 113         if (request_mem_region(mmio_addr, mmio_len, DRV_NAME) == NULL) {
 114                 dev_err(&pdev->dev, "MEM I/O resource 0x%lx @ 0x%lx busy\n",
 115                        mmio_addr, mmio_len);
 116                 ret = -EBUSY;
 117                 goto pci_out;
 118         }
 119
 120         if (request_region(ioaddr, iolen, DRV_NAME) == NULL) {
 121                 dev_err(&pdev->dev, "I/O resource 0x%lx @ 0x%lx busy\n",
 122                        iolen, ioaddr);
 123                 ret = -EBUSY;
 124                 goto mem_out;
 125         }
 126
 127         platform_mmio = mmio_addr;
 128         platform_mmiolen = mmio_len;
 129
 130         if (!xen_have_vector_callback) {
 131                 ret = xen_allocate_irq(pdev);
 132                 if (ret) {
 133                         dev_warn(&pdev->dev, "request_irq failed err=%d\n", ret);
 134                         goto out;
 135                 }
 136                 callback_via = get_callback_via(pdev);
 137                 ret = xen_set_callback_via(callback_via);
 138                 if (ret) {
 139                         dev_warn(&pdev->dev, "Unable to set the evtchn callback "
 140                                          "err=%d\n", ret);
 141                         goto out;
 142                 }
 143         }
 144
 145         max_nr_gframes = gnttab_max_grant_frames();
 146         xen_hvm_resume_frames = alloc_xen_mmio(PAGE_SIZE * max_nr_gframes);
 147         ret = gnttab_init();
 148         if (ret)
 149                 goto out;
 150         xenbus_probe(NULL);
 151         return 0;
 152
 153 out:
 154         release_region(ioaddr, iolen);
 155 mem_out:
 156         release_mem_region(mmio_addr, mmio_len);
 157 pci_out:
 158         pci_disable_device(pdev);
 159         return ret;
 160 }
 161
 162 static struct pci_device_id platform_pci_tbl[] __devinitdata = {
 163         {PCI_VENDOR_ID_XEN, PCI_DEVICE_ID_XEN_PLATFORM,
 164                 PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
 165         {0,}
 166 };
 167
 168 MODULE_DEVICE_TABLE(pci, platform_pci_tbl);
 169
 170 static struct pci_driver platform_driver = {
 171         .name =           DRV_NAME,
 172         .probe =          platform_pci_init,
 173         .id_table =       platform_pci_tbl,
 174 };
 175
 176 static int __init platform_pci_module_init(void)
 177 {
 178         return pci_register_driver(&platform_driver);
 179 }
 180
 181 module_init(platform_pci_module_init);