1 // SPDX-License-Identifier: GPL-2.0-only 2 /****************************************************************************** 3 * platform-pci.c 4 * 5 * Xen platform PCI device driver 6 * 7 * Authors: ssmith@xensource.com and stefano.stabellini@eu.citrix.com 8 * 9 * Copyright (c) 2005, Intel Corporation. 10 * Copyright (c) 2007, XenSource Inc. 11 * Copyright (c) 2010, Citrix 12 */ 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 29 static unsigned long platform_mmio; 30 static unsigned long platform_mmio_alloc; 31 static unsigned long platform_mmiolen; 32 static uint64_t callback_via; 33 34 static 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 45 static 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 65 static irqreturn_t do_hvm_evtchn_intr(int irq, void *dev_id) 66 { 67 xen_hvm_evtchn_do_upcall(); 68 return IRQ_HANDLED; 69 } 70 71 static int xen_allocate_irq(struct pci_dev *pdev) 72 { 73 return request_irq(pdev->irq, do_hvm_evtchn_intr, 74 IRQF_NOBALANCING | IRQF_TRIGGER_RISING, 75 "xen-platform-pci", pdev); 76 } 77 78 static int platform_pci_resume(struct device *dev) 79 { 80 int err; 81 82 if (xen_have_vector_callback) 83 return 0; 84 85 err = xen_set_callback_via(callback_via); 86 if (err) { 87 dev_err(dev, "platform_pci_resume failure!\n"); 88 return err; 89 } 90 return 0; 91 } 92 93 static int platform_pci_probe(struct pci_dev *pdev, 94 const struct pci_device_id *ent) 95 { 96 int i, ret; 97 long ioaddr; 98 long mmio_addr, mmio_len; 99 unsigned int max_nr_gframes; 100 unsigned long grant_frames; 101 102 if (!xen_domain()) 103 return -ENODEV; 104 105 i = pci_enable_device(pdev); 106 if (i) 107 return i; 108 109 ioaddr = pci_resource_start(pdev, 0); 110 111 mmio_addr = pci_resource_start(pdev, 1); 112 mmio_len = pci_resource_len(pdev, 1); 113 114 if (mmio_addr == 0 || ioaddr == 0) { 115 dev_err(&pdev->dev, "no resources found\n"); 116 ret = -ENOENT; 117 goto pci_out; 118 } 119 120 ret = pci_request_region(pdev, 1, DRV_NAME); 121 if (ret < 0) 122 goto pci_out; 123 124 ret = pci_request_region(pdev, 0, DRV_NAME); 125 if (ret < 0) 126 goto mem_out; 127 128 platform_mmio = mmio_addr; 129 platform_mmiolen = mmio_len; 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 /* 137 * It doesn't strictly *have* to run on CPU0 but it sure 138 * as hell better process the event channel ports delivered 139 * to CPU0. 140 */ 141 irq_set_affinity(pdev->irq, cpumask_of(0)); 142 143 callback_via = get_callback_via(pdev); 144 ret = xen_set_callback_via(callback_via); 145 if (ret) { 146 dev_warn(&pdev->dev, "Unable to set the evtchn callback " 147 "err=%d\n", ret); 148 goto irq_out; 149 } 150 } 151 152 max_nr_gframes = gnttab_max_grant_frames(); 153 grant_frames = alloc_xen_mmio(PAGE_SIZE * max_nr_gframes); 154 ret = gnttab_setup_auto_xlat_frames(grant_frames); 155 if (ret) 156 goto irq_out; 157 ret = gnttab_init(); 158 if (ret) 159 goto grant_out; 160 return 0; 161 grant_out: 162 gnttab_free_auto_xlat_frames(); 163 irq_out: 164 if (!xen_have_vector_callback) 165 free_irq(pdev->irq, pdev); 166 out: 167 pci_release_region(pdev, 0); 168 mem_out: 169 pci_release_region(pdev, 1); 170 pci_out: 171 pci_disable_device(pdev); 172 return ret; 173 } 174 175 static const struct pci_device_id platform_pci_tbl[] = { 176 {PCI_VENDOR_ID_XEN, PCI_DEVICE_ID_XEN_PLATFORM, 177 PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0}, 178 {0,} 179 }; 180 181 static const struct dev_pm_ops platform_pm_ops = { 182 .resume_noirq = platform_pci_resume, 183 }; 184 185 static struct pci_driver platform_driver = { 186 .name = DRV_NAME, 187 .probe = platform_pci_probe, 188 .id_table = platform_pci_tbl, 189 .driver = { 190 .pm = &platform_pm_ops, 191 }, 192 }; 193 194 builtin_pci_driver(platform_driver); 195