xref: /kvm-unit-tests/lib/pci.c (revision e954ce23cd9f942b3ddf16f4932087b3ee789259)
1 /*
2  * Copyright (C) 2013, Red Hat Inc, Michael S. Tsirkin <mst@redhat.com>
3  *
4  * This work is licensed under the terms of the GNU LGPL, version 2.
5  */
6 #include <linux/pci_regs.h>
7 #include "pci.h"
8 #include "asm/pci.h"
9 
10 bool pci_dev_exists(pcidevaddr_t dev)
11 {
12 	return (pci_config_readw(dev, PCI_VENDOR_ID) != 0xffff &&
13 		pci_config_readw(dev, PCI_DEVICE_ID) != 0xffff);
14 }
15 
16 void pci_dev_init(struct pci_dev *dev, pcidevaddr_t bdf)
17 {
18        memset(dev, 0, sizeof(*dev));
19        dev->bdf = bdf;
20 }
21 
22 /* Scan bus look for a specific device. Only bus 0 scanned for now. */
23 pcidevaddr_t pci_find_dev(uint16_t vendor_id, uint16_t device_id)
24 {
25 	pcidevaddr_t dev;
26 
27 	for (dev = 0; dev < PCI_DEVFN_MAX; ++dev) {
28 		if (pci_config_readw(dev, PCI_VENDOR_ID) == vendor_id &&
29 		    pci_config_readw(dev, PCI_DEVICE_ID) == device_id)
30 			return dev;
31 	}
32 
33 	return PCIDEVADDR_INVALID;
34 }
35 
36 uint32_t pci_bar_mask(uint32_t bar)
37 {
38 	return (bar & PCI_BASE_ADDRESS_SPACE_IO) ?
39 		PCI_BASE_ADDRESS_IO_MASK : PCI_BASE_ADDRESS_MEM_MASK;
40 }
41 
42 uint32_t pci_bar_get(struct pci_dev *dev, int bar_num)
43 {
44 	return pci_config_readl(dev->bdf, PCI_BASE_ADDRESS_0 +
45 				bar_num * 4);
46 }
47 
48 phys_addr_t pci_bar_get_addr(struct pci_dev *dev, int bar_num)
49 {
50 	uint32_t bar = pci_bar_get(dev, bar_num);
51 	uint32_t mask = pci_bar_mask(bar);
52 	uint64_t addr = bar & mask;
53 	phys_addr_t phys_addr;
54 
55 	if (pci_bar_is64(dev, bar_num))
56 		addr |= (uint64_t)pci_bar_get(dev, bar_num + 1) << 32;
57 
58 	phys_addr = pci_translate_addr(dev->bdf, addr);
59 	assert(phys_addr != INVALID_PHYS_ADDR);
60 
61 	return phys_addr;
62 }
63 
64 void pci_bar_set_addr(struct pci_dev *dev, int bar_num, phys_addr_t addr)
65 {
66 	int off = PCI_BASE_ADDRESS_0 + bar_num * 4;
67 
68 	pci_config_writel(dev->bdf, off, (uint32_t)addr);
69 
70 	if (pci_bar_is64(dev, bar_num))
71 		pci_config_writel(dev->bdf, off + 4,
72 				  (uint32_t)(addr >> 32));
73 }
74 
75 /*
76  * To determine the amount of address space needed by a PCI device,
77  * one must save the original value of the BAR, write a value of
78  * all 1's to the register, and then read it back. The amount of
79  * memory can be then determined by masking the information bits,
80  * performing a bitwise NOT, and incrementing the value by 1.
81  *
82  * The following pci_bar_size_helper() and pci_bar_size() functions
83  * implement the algorithm.
84  */
85 static uint32_t pci_bar_size_helper(struct pci_dev *dev, int bar_num)
86 {
87 	int off = PCI_BASE_ADDRESS_0 + bar_num * 4;
88 	uint16_t bdf = dev->bdf;
89 	uint32_t bar, val;
90 
91 	bar = pci_config_readl(bdf, off);
92 	pci_config_writel(bdf, off, ~0u);
93 	val = pci_config_readl(bdf, off);
94 	pci_config_writel(bdf, off, bar);
95 
96 	return val;
97 }
98 
99 phys_addr_t pci_bar_size(struct pci_dev *dev, int bar_num)
100 {
101 	uint32_t bar, size;
102 
103 	size = pci_bar_size_helper(dev, bar_num);
104 	if (!size)
105 		return 0;
106 
107 	bar = pci_bar_get(dev, bar_num);
108 	size &= pci_bar_mask(bar);
109 
110 	if (pci_bar_is64(dev, bar_num)) {
111 		phys_addr_t size64 = pci_bar_size_helper(dev, bar_num + 1);
112 		size64 = (size64 << 32) | size;
113 
114 		return ~size64 + 1;
115 	} else {
116 		return ~size + 1;
117 	}
118 }
119 
120 bool pci_bar_is_memory(struct pci_dev *dev, int bar_num)
121 {
122 	uint32_t bar = pci_bar_get(dev, bar_num);
123 
124 	return !(bar & PCI_BASE_ADDRESS_SPACE_IO);
125 }
126 
127 bool pci_bar_is_valid(struct pci_dev *dev, int bar_num)
128 {
129 	return pci_bar_get(dev, bar_num);
130 }
131 
132 bool pci_bar_is64(struct pci_dev *dev, int bar_num)
133 {
134 	uint32_t bar = pci_bar_get(dev, bar_num);
135 
136 	if (bar & PCI_BASE_ADDRESS_SPACE_IO)
137 		return false;
138 
139 	return (bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
140 		      PCI_BASE_ADDRESS_MEM_TYPE_64;
141 }
142 
143 void pci_bar_print(struct pci_dev *dev, int bar_num)
144 {
145 	phys_addr_t size, start, end;
146 	uint32_t bar;
147 
148 	size = pci_bar_size(dev, bar_num);
149 	if (!size)
150 		return;
151 
152 	bar = pci_bar_get(dev, bar_num);
153 	start = pci_bar_get_addr(dev, bar_num);
154 	end = start + size - 1;
155 
156 	if (pci_bar_is64(dev, bar_num)) {
157 		printf("BAR#%d,%d [%" PRIx64 "-%" PRIx64 " ",
158 		       bar_num, bar_num + 1, start, end);
159 	} else {
160 		printf("BAR#%d [%02x-%02x ",
161 		       bar_num, (uint32_t)start, (uint32_t)end);
162 	}
163 
164 	if (bar & PCI_BASE_ADDRESS_SPACE_IO) {
165 		printf("PIO");
166 	} else {
167 		printf("MEM");
168 		switch (bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK) {
169 		case PCI_BASE_ADDRESS_MEM_TYPE_32:
170 			printf("32");
171 			break;
172 		case PCI_BASE_ADDRESS_MEM_TYPE_1M:
173 			printf("1M");
174 			break;
175 		case PCI_BASE_ADDRESS_MEM_TYPE_64:
176 			printf("64");
177 			break;
178 		default:
179 			assert(0);
180 		}
181 	}
182 
183 	if (bar & PCI_BASE_ADDRESS_MEM_PREFETCH)
184 		printf("/p");
185 
186 	printf("]");
187 }
188 
189 void pci_dev_print_id(pcidevaddr_t dev)
190 {
191 	printf("00.%02x.%1x %04x:%04x", dev / 8, dev % 8,
192 		pci_config_readw(dev, PCI_VENDOR_ID),
193 		pci_config_readw(dev, PCI_DEVICE_ID));
194 }
195 
196 static void pci_dev_print(pcidevaddr_t dev)
197 {
198 	uint8_t header = pci_config_readb(dev, PCI_HEADER_TYPE);
199 	uint8_t progif = pci_config_readb(dev, PCI_CLASS_PROG);
200 	uint8_t subclass = pci_config_readb(dev, PCI_CLASS_DEVICE);
201 	uint8_t class = pci_config_readb(dev, PCI_CLASS_DEVICE + 1);
202 	struct pci_dev pci_dev;
203 	int i;
204 
205 	pci_dev_init(&pci_dev, dev);
206 
207 	pci_dev_print_id(dev);
208 	printf(" type %02x progif %02x class %02x subclass %02x\n",
209 	       header, progif, class, subclass);
210 
211 	if ((header & PCI_HEADER_TYPE_MASK) != PCI_HEADER_TYPE_NORMAL)
212 		return;
213 
214 	for (i = 0; i < PCI_BAR_NUM; i++) {
215 		if (pci_bar_size(&pci_dev, i)) {
216 			printf("\t");
217 			pci_bar_print(&pci_dev, i);
218 			printf("\n");
219 		}
220 		if (pci_bar_is64(&pci_dev, i))
221 			i++;
222 	}
223 }
224 
225 void pci_print(void)
226 {
227 	pcidevaddr_t dev;
228 
229 	for (dev = 0; dev < PCI_DEVFN_MAX; ++dev) {
230 		if (pci_dev_exists(dev))
231 			pci_dev_print(dev);
232 	}
233 }
234 
235 void pci_scan_bars(struct pci_dev *dev)
236 {
237 	int i;
238 
239 	for (i = 0; i < PCI_BAR_NUM; i++) {
240 		if (!pci_bar_is_valid(dev, i))
241 			continue;
242 		dev->resource[i] = pci_bar_get_addr(dev, i);
243 		if (pci_bar_is64(dev, i)) {
244 			i++;
245 			dev->resource[i] = (phys_addr_t)0;
246 		}
247 	}
248 }
249