1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | |
3 | #include "linux/virtio_pci.h" |
4 | #include <linux/virtio_pci_legacy.h> |
5 | #include <linux/module.h> |
6 | #include <linux/pci.h> |
7 | |
8 | |
9 | /* |
10 | * vp_legacy_probe: probe the legacy virtio pci device, note that the |
11 | * caller is required to enable PCI device before calling this function. |
12 | * @ldev: the legacy virtio-pci device |
13 | * |
14 | * Return 0 on succeed otherwise fail |
15 | */ |
16 | int vp_legacy_probe(struct virtio_pci_legacy_device *ldev) |
17 | { |
18 | struct pci_dev *pci_dev = ldev->pci_dev; |
19 | int rc; |
20 | |
21 | /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */ |
22 | if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f) |
23 | return -ENODEV; |
24 | |
25 | if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) |
26 | return -ENODEV; |
27 | |
28 | rc = dma_set_mask(dev: &pci_dev->dev, DMA_BIT_MASK(64)); |
29 | if (rc) { |
30 | rc = dma_set_mask_and_coherent(dev: &pci_dev->dev, DMA_BIT_MASK(32)); |
31 | } else { |
32 | /* |
33 | * The virtio ring base address is expressed as a 32-bit PFN, |
34 | * with a page size of 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT. |
35 | */ |
36 | dma_set_coherent_mask(dev: &pci_dev->dev, |
37 | DMA_BIT_MASK(32 + VIRTIO_PCI_QUEUE_ADDR_SHIFT)); |
38 | } |
39 | |
40 | if (rc) |
41 | dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n" ); |
42 | |
43 | rc = pci_request_region(pci_dev, 0, "virtio-pci-legacy" ); |
44 | if (rc) |
45 | return rc; |
46 | |
47 | ldev->ioaddr = pci_iomap(dev: pci_dev, bar: 0, max: 0); |
48 | if (!ldev->ioaddr) { |
49 | rc = -EIO; |
50 | goto err_iomap; |
51 | } |
52 | |
53 | ldev->isr = ldev->ioaddr + VIRTIO_PCI_ISR; |
54 | |
55 | ldev->id.vendor = pci_dev->subsystem_vendor; |
56 | ldev->id.device = pci_dev->subsystem_device; |
57 | |
58 | return 0; |
59 | err_iomap: |
60 | pci_release_region(pci_dev, 0); |
61 | return rc; |
62 | } |
63 | EXPORT_SYMBOL_GPL(vp_legacy_probe); |
64 | |
65 | /* |
66 | * vp_legacy_probe: remove and cleanup the legacy virtio pci device |
67 | * @ldev: the legacy virtio-pci device |
68 | */ |
69 | void vp_legacy_remove(struct virtio_pci_legacy_device *ldev) |
70 | { |
71 | struct pci_dev *pci_dev = ldev->pci_dev; |
72 | |
73 | pci_iounmap(dev: pci_dev, ldev->ioaddr); |
74 | pci_release_region(pci_dev, 0); |
75 | } |
76 | EXPORT_SYMBOL_GPL(vp_legacy_remove); |
77 | |
78 | /* |
79 | * vp_legacy_get_features - get features from device |
80 | * @ldev: the legacy virtio-pci device |
81 | * |
82 | * Returns the features read from the device |
83 | */ |
84 | u64 vp_legacy_get_features(struct virtio_pci_legacy_device *ldev) |
85 | { |
86 | |
87 | return ioread32(ldev->ioaddr + VIRTIO_PCI_HOST_FEATURES); |
88 | } |
89 | EXPORT_SYMBOL_GPL(vp_legacy_get_features); |
90 | |
91 | /* |
92 | * vp_legacy_get_driver_features - get driver features from device |
93 | * @ldev: the legacy virtio-pci device |
94 | * |
95 | * Returns the driver features read from the device |
96 | */ |
97 | u64 vp_legacy_get_driver_features(struct virtio_pci_legacy_device *ldev) |
98 | { |
99 | return ioread32(ldev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); |
100 | } |
101 | EXPORT_SYMBOL_GPL(vp_legacy_get_driver_features); |
102 | |
103 | /* |
104 | * vp_legacy_set_features - set features to device |
105 | * @ldev: the legacy virtio-pci device |
106 | * @features: the features set to device |
107 | */ |
108 | void vp_legacy_set_features(struct virtio_pci_legacy_device *ldev, |
109 | u32 features) |
110 | { |
111 | iowrite32(features, ldev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); |
112 | } |
113 | EXPORT_SYMBOL_GPL(vp_legacy_set_features); |
114 | |
115 | /* |
116 | * vp_legacy_get_status - get the device status |
117 | * @ldev: the legacy virtio-pci device |
118 | * |
119 | * Returns the status read from device |
120 | */ |
121 | u8 vp_legacy_get_status(struct virtio_pci_legacy_device *ldev) |
122 | { |
123 | return ioread8(ldev->ioaddr + VIRTIO_PCI_STATUS); |
124 | } |
125 | EXPORT_SYMBOL_GPL(vp_legacy_get_status); |
126 | |
127 | /* |
128 | * vp_legacy_set_status - set status to device |
129 | * @ldev: the legacy virtio-pci device |
130 | * @status: the status set to device |
131 | */ |
132 | void vp_legacy_set_status(struct virtio_pci_legacy_device *ldev, |
133 | u8 status) |
134 | { |
135 | iowrite8(status, ldev->ioaddr + VIRTIO_PCI_STATUS); |
136 | } |
137 | EXPORT_SYMBOL_GPL(vp_legacy_set_status); |
138 | |
139 | /* |
140 | * vp_legacy_queue_vector - set the MSIX vector for a specific virtqueue |
141 | * @ldev: the legacy virtio-pci device |
142 | * @index: queue index |
143 | * @vector: the config vector |
144 | * |
145 | * Returns the config vector read from the device |
146 | */ |
147 | u16 vp_legacy_queue_vector(struct virtio_pci_legacy_device *ldev, |
148 | u16 index, u16 vector) |
149 | { |
150 | iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); |
151 | iowrite16(vector, ldev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); |
152 | /* Flush the write out to device */ |
153 | return ioread16(ldev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); |
154 | } |
155 | EXPORT_SYMBOL_GPL(vp_legacy_queue_vector); |
156 | |
157 | /* |
158 | * vp_legacy_config_vector - set the vector for config interrupt |
159 | * @ldev: the legacy virtio-pci device |
160 | * @vector: the config vector |
161 | * |
162 | * Returns the config vector read from the device |
163 | */ |
164 | u16 vp_legacy_config_vector(struct virtio_pci_legacy_device *ldev, |
165 | u16 vector) |
166 | { |
167 | /* Setup the vector used for configuration events */ |
168 | iowrite16(vector, ldev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); |
169 | /* Verify we had enough resources to assign the vector */ |
170 | /* Will also flush the write out to device */ |
171 | return ioread16(ldev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); |
172 | } |
173 | EXPORT_SYMBOL_GPL(vp_legacy_config_vector); |
174 | |
175 | /* |
176 | * vp_legacy_set_queue_address - set the virtqueue address |
177 | * @ldev: the legacy virtio-pci device |
178 | * @index: the queue index |
179 | * @queue_pfn: pfn of the virtqueue |
180 | */ |
181 | void vp_legacy_set_queue_address(struct virtio_pci_legacy_device *ldev, |
182 | u16 index, u32 queue_pfn) |
183 | { |
184 | iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); |
185 | iowrite32(queue_pfn, ldev->ioaddr + VIRTIO_PCI_QUEUE_PFN); |
186 | } |
187 | EXPORT_SYMBOL_GPL(vp_legacy_set_queue_address); |
188 | |
189 | /* |
190 | * vp_legacy_get_queue_enable - enable a virtqueue |
191 | * @ldev: the legacy virtio-pci device |
192 | * @index: the queue index |
193 | * |
194 | * Returns whether a virtqueue is enabled or not |
195 | */ |
196 | bool vp_legacy_get_queue_enable(struct virtio_pci_legacy_device *ldev, |
197 | u16 index) |
198 | { |
199 | iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); |
200 | return ioread32(ldev->ioaddr + VIRTIO_PCI_QUEUE_PFN); |
201 | } |
202 | EXPORT_SYMBOL_GPL(vp_legacy_get_queue_enable); |
203 | |
204 | /* |
205 | * vp_legacy_get_queue_size - get size for a virtqueue |
206 | * @ldev: the legacy virtio-pci device |
207 | * @index: the queue index |
208 | * |
209 | * Returns the size of the virtqueue |
210 | */ |
211 | u16 vp_legacy_get_queue_size(struct virtio_pci_legacy_device *ldev, |
212 | u16 index) |
213 | { |
214 | iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); |
215 | return ioread16(ldev->ioaddr + VIRTIO_PCI_QUEUE_NUM); |
216 | } |
217 | EXPORT_SYMBOL_GPL(vp_legacy_get_queue_size); |
218 | |
219 | MODULE_VERSION("0.1" ); |
220 | MODULE_DESCRIPTION("Legacy Virtio PCI Device" ); |
221 | MODULE_AUTHOR("Wu Zongyong <wuzongyong@linux.alibaba.com>" ); |
222 | MODULE_LICENSE("GPL" ); |
223 | |