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(bus: 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 | return xen_evtchn_do_upcall(); |
68 | } |
69 | |
70 | static int xen_allocate_irq(struct pci_dev *pdev) |
71 | { |
72 | return request_irq(irq: pdev->irq, handler: do_hvm_evtchn_intr, |
73 | IRQF_NOBALANCING | IRQF_SHARED, |
74 | name: "xen-platform-pci" , dev: pdev); |
75 | } |
76 | |
77 | static 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(via: callback_via); |
85 | if (err) { |
86 | dev_err(dev, "platform_pci_resume failure!\n" ); |
87 | return err; |
88 | } |
89 | return 0; |
90 | } |
91 | |
92 | static 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(dev: 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 sure |
137 | * as hell better process the event channel ports delivered |
138 | * to CPU0. |
139 | */ |
140 | irq_set_affinity(irq: pdev->irq, cpumask_of(0)); |
141 | |
142 | callback_via = get_callback_via(pdev); |
143 | ret = xen_set_callback_via(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(addr: grant_frames); |
154 | if (ret) |
155 | goto irq_out; |
156 | ret = gnttab_init(); |
157 | if (ret) |
158 | goto grant_out; |
159 | return 0; |
160 | grant_out: |
161 | gnttab_free_auto_xlat_frames(); |
162 | irq_out: |
163 | if (!xen_have_vector_callback) |
164 | free_irq(pdev->irq, pdev); |
165 | out: |
166 | pci_release_region(pdev, 0); |
167 | mem_out: |
168 | pci_release_region(pdev, 1); |
169 | pci_out: |
170 | pci_disable_device(dev: pdev); |
171 | return ret; |
172 | } |
173 | |
174 | static 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 | |
180 | static const struct dev_pm_ops platform_pm_ops = { |
181 | .resume_noirq = platform_pci_resume, |
182 | }; |
183 | |
184 | static 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 | |
193 | builtin_pci_driver(platform_driver); |
194 | |