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1// SPDX-License-Identifier: GPL-2.0-only2/******************************************************************************3 * platform-pci.c4 *5 * Xen platform PCI device driver6 *7 * Authors: ssmith@xensource.com and stefano.stabellini@eu.citrix.com8 *9 * Copyright (c) 2005, Intel Corporation.10 * Copyright (c) 2007, XenSource Inc.11 * Copyright (c) 2010, Citrix12 */13 14 15#include <linux/interrupt.h>16#include <linux/io.h>17#include <linux/init.h>18#include <linux/pci.h>19 20#include <xen/platform_pci.h>21#include <xen/grant_table.h>22#include <xen/xenbus.h>23#include <xen/events.h>24#include <xen/hvm.h>25#include <xen/xen-ops.h>26 27#define DRV_NAME "xen-platform-pci"28 29static unsigned long platform_mmio;30static unsigned long platform_mmio_alloc;31static unsigned long platform_mmiolen;32static uint64_t callback_via;33 34static unsigned long alloc_xen_mmio(unsigned long len)35{36 unsigned long addr;37 38 addr = platform_mmio + platform_mmio_alloc;39 platform_mmio_alloc += len;40 BUG_ON(platform_mmio_alloc > platform_mmiolen);41 42 return addr;43}44 45static uint64_t get_callback_via(struct pci_dev *pdev)46{47 u8 pin;48 int irq;49 50 irq = pdev->irq;51 if (irq < 16)52 return irq; /* ISA IRQ */53 54 pin = pdev->pin;55 56 /* We don't know the GSI. Specify the PCI INTx line instead. */57 return ((uint64_t)HVM_PARAM_CALLBACK_TYPE_PCI_INTX <<58 HVM_CALLBACK_VIA_TYPE_SHIFT) |59 ((uint64_t)pci_domain_nr(pdev->bus) << 32) |60 ((uint64_t)pdev->bus->number << 16) |61 ((uint64_t)(pdev->devfn & 0xff) << 8) |62 ((uint64_t)(pin - 1) & 3);63}64 65static irqreturn_t do_hvm_evtchn_intr(int irq, void *dev_id)66{67 return xen_evtchn_do_upcall();68}69 70static int xen_allocate_irq(struct pci_dev *pdev)71{72 return request_irq(pdev->irq, do_hvm_evtchn_intr,73 IRQF_NOBALANCING | IRQF_SHARED,74 "xen-platform-pci", pdev);75}76 77static int platform_pci_resume(struct device *dev)78{79 int err;80 81 if (xen_have_vector_callback)82 return 0;83 84 err = xen_set_callback_via(callback_via);85 if (err) {86 dev_err(dev, "platform_pci_resume failure!\n");87 return err;88 }89 return 0;90}91 92static int platform_pci_probe(struct pci_dev *pdev,93 const struct pci_device_id *ent)94{95 int i, ret;96 long ioaddr;97 long mmio_addr, mmio_len;98 unsigned int max_nr_gframes;99 unsigned long grant_frames;100 101 if (!xen_domain())102 return -ENODEV;103 104 i = pci_enable_device(pdev);105 if (i)106 return i;107 108 ioaddr = pci_resource_start(pdev, 0);109 110 mmio_addr = pci_resource_start(pdev, 1);111 mmio_len = pci_resource_len(pdev, 1);112 113 if (mmio_addr == 0 || ioaddr == 0) {114 dev_err(&pdev->dev, "no resources found\n");115 ret = -ENOENT;116 goto pci_out;117 }118 119 ret = pci_request_region(pdev, 1, DRV_NAME);120 if (ret < 0)121 goto pci_out;122 123 ret = pci_request_region(pdev, 0, DRV_NAME);124 if (ret < 0)125 goto mem_out;126 127 platform_mmio = mmio_addr;128 platform_mmiolen = mmio_len;129 if (!xen_have_vector_callback) {130 ret = xen_allocate_irq(pdev);131 if (ret) {132 dev_warn(&pdev->dev, "request_irq failed err=%d\n", ret);133 goto out;134 }135 /*136 * It doesn't strictly *have* to run on CPU0 but it sure137 * as hell better process the event channel ports delivered138 * to CPU0.139 */140 irq_set_affinity(pdev->irq, cpumask_of(0));141 142 callback_via = get_callback_via(pdev);143 ret = xen_set_callback_via(callback_via);144 if (ret) {145 dev_warn(&pdev->dev, "Unable to set the evtchn callback "146 "err=%d\n", ret);147 goto irq_out;148 }149 }150 151 max_nr_gframes = gnttab_max_grant_frames();152 grant_frames = alloc_xen_mmio(PAGE_SIZE * max_nr_gframes);153 ret = gnttab_setup_auto_xlat_frames(grant_frames);154 if (ret)155 goto irq_out;156 ret = gnttab_init();157 if (ret)158 goto grant_out;159 return 0;160grant_out:161 gnttab_free_auto_xlat_frames();162irq_out:163 if (!xen_have_vector_callback)164 free_irq(pdev->irq, pdev);165out:166 pci_release_region(pdev, 0);167mem_out:168 pci_release_region(pdev, 1);169pci_out:170 pci_disable_device(pdev);171 return ret;172}173 174static const struct pci_device_id platform_pci_tbl[] = {175 {PCI_VENDOR_ID_XEN, PCI_DEVICE_ID_XEN_PLATFORM,176 PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},177 {0,}178};179 180static const struct dev_pm_ops platform_pm_ops = {181 .resume_noirq = platform_pci_resume,182};183 184static struct pci_driver platform_driver = {185 .name = DRV_NAME,186 .probe = platform_pci_probe,187 .id_table = platform_pci_tbl,188 .driver = {189 .pm = &platform_pm_ops,190 },191};192 193builtin_pci_driver(platform_driver);194