xref: /openbmc/linux/arch/alpha/kernel/pci-sysfs.c (revision fd589a8f)
1 /*
2  * arch/alpha/kernel/pci-sysfs.c
3  *
4  * Copyright (C) 2009 Ivan Kokshaysky
5  *
6  * Alpha PCI resource files.
7  *
8  * Loosely based on generic HAVE_PCI_MMAP implementation in
9  * drivers/pci/pci-sysfs.c
10  */
11 
12 #include <linux/sched.h>
13 #include <linux/pci.h>
14 
15 static int hose_mmap_page_range(struct pci_controller *hose,
16 				struct vm_area_struct *vma,
17 				enum pci_mmap_state mmap_type, int sparse)
18 {
19 	unsigned long base;
20 
21 	if (mmap_type == pci_mmap_mem)
22 		base = sparse ? hose->sparse_mem_base : hose->dense_mem_base;
23 	else
24 		base = sparse ? hose->sparse_io_base : hose->dense_io_base;
25 
26 	vma->vm_pgoff += base >> PAGE_SHIFT;
27 	vma->vm_flags |= (VM_IO | VM_RESERVED);
28 
29 	return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
30 				  vma->vm_end - vma->vm_start,
31 				  vma->vm_page_prot);
32 }
33 
34 static int __pci_mmap_fits(struct pci_dev *pdev, int num,
35 			   struct vm_area_struct *vma, int sparse)
36 {
37 	unsigned long nr, start, size;
38 	int shift = sparse ? 5 : 0;
39 
40 	nr = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
41 	start = vma->vm_pgoff;
42 	size = ((pci_resource_len(pdev, num) - 1) >> (PAGE_SHIFT - shift)) + 1;
43 
44 	if (start < size && size - start >= nr)
45 		return 1;
46 	WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on %s BAR %d "
47 		"(size 0x%08lx)\n",
48 		current->comm, sparse ? " sparse" : "", start, start + nr,
49 		pci_name(pdev), num, size);
50 	return 0;
51 }
52 
53 /**
54  * pci_mmap_resource - map a PCI resource into user memory space
55  * @kobj: kobject for mapping
56  * @attr: struct bin_attribute for the file being mapped
57  * @vma: struct vm_area_struct passed into the mmap
58  * @sparse: address space type
59  *
60  * Use the bus mapping routines to map a PCI resource into userspace.
61  */
62 static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
63 			     struct vm_area_struct *vma, int sparse)
64 {
65 	struct pci_dev *pdev = to_pci_dev(container_of(kobj,
66 						       struct device, kobj));
67 	struct resource *res = (struct resource *)attr->private;
68 	enum pci_mmap_state mmap_type;
69 	struct pci_bus_region bar;
70 	int i;
71 
72 	for (i = 0; i < PCI_ROM_RESOURCE; i++)
73 		if (res == &pdev->resource[i])
74 			break;
75 	if (i >= PCI_ROM_RESOURCE)
76 		return -ENODEV;
77 
78 	if (!__pci_mmap_fits(pdev, i, vma, sparse))
79 		return -EINVAL;
80 
81 	if (iomem_is_exclusive(res->start))
82 		return -EINVAL;
83 
84 	pcibios_resource_to_bus(pdev, &bar, res);
85 	vma->vm_pgoff += bar.start >> (PAGE_SHIFT - (sparse ? 5 : 0));
86 	mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
87 
88 	return hose_mmap_page_range(pdev->sysdata, vma, mmap_type, sparse);
89 }
90 
91 static int pci_mmap_resource_sparse(struct kobject *kobj,
92 				    struct bin_attribute *attr,
93 				    struct vm_area_struct *vma)
94 {
95 	return pci_mmap_resource(kobj, attr, vma, 1);
96 }
97 
98 static int pci_mmap_resource_dense(struct kobject *kobj,
99 				   struct bin_attribute *attr,
100 				   struct vm_area_struct *vma)
101 {
102 	return pci_mmap_resource(kobj, attr, vma, 0);
103 }
104 
105 /**
106  * pci_remove_resource_files - cleanup resource files
107  * @dev: dev to cleanup
108  *
109  * If we created resource files for @dev, remove them from sysfs and
110  * free their resources.
111  */
112 void pci_remove_resource_files(struct pci_dev *pdev)
113 {
114 	int i;
115 
116 	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
117 		struct bin_attribute *res_attr;
118 
119 		res_attr = pdev->res_attr[i];
120 		if (res_attr) {
121 			sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
122 			kfree(res_attr);
123 		}
124 
125 		res_attr = pdev->res_attr_wc[i];
126 		if (res_attr) {
127 			sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
128 			kfree(res_attr);
129 		}
130 	}
131 }
132 
133 static int sparse_mem_mmap_fits(struct pci_dev *pdev, int num)
134 {
135 	struct pci_bus_region bar;
136 	struct pci_controller *hose = pdev->sysdata;
137 	long dense_offset;
138 	unsigned long sparse_size;
139 
140 	pcibios_resource_to_bus(pdev, &bar, &pdev->resource[num]);
141 
142 	/* All core logic chips have 4G sparse address space, except
143 	   CIA which has 16G (see xxx_SPARSE_MEM and xxx_DENSE_MEM
144 	   definitions in asm/core_xxx.h files). This corresponds
145 	   to 128M or 512M of the bus space. */
146 	dense_offset = (long)(hose->dense_mem_base - hose->sparse_mem_base);
147 	sparse_size = dense_offset >= 0x400000000UL ? 0x20000000 : 0x8000000;
148 
149 	return bar.end < sparse_size;
150 }
151 
152 static int pci_create_one_attr(struct pci_dev *pdev, int num, char *name,
153 			       char *suffix, struct bin_attribute *res_attr,
154 			       unsigned long sparse)
155 {
156 	size_t size = pci_resource_len(pdev, num);
157 
158 	sprintf(name, "resource%d%s", num, suffix);
159 	res_attr->mmap = sparse ? pci_mmap_resource_sparse :
160 				  pci_mmap_resource_dense;
161 	res_attr->attr.name = name;
162 	res_attr->attr.mode = S_IRUSR | S_IWUSR;
163 	res_attr->size = sparse ? size << 5 : size;
164 	res_attr->private = &pdev->resource[num];
165 	return sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
166 }
167 
168 static int pci_create_attr(struct pci_dev *pdev, int num)
169 {
170 	/* allocate attribute structure, piggyback attribute name */
171 	int retval, nlen1, nlen2 = 0, res_count = 1;
172 	unsigned long sparse_base, dense_base;
173 	struct bin_attribute *attr;
174 	struct pci_controller *hose = pdev->sysdata;
175 	char *suffix, *attr_name;
176 
177 	suffix = "";	/* Assume bwx machine, normal resourceN files. */
178 	nlen1 = 10;
179 
180 	if (pdev->resource[num].flags & IORESOURCE_MEM) {
181 		sparse_base = hose->sparse_mem_base;
182 		dense_base = hose->dense_mem_base;
183 		if (sparse_base && !sparse_mem_mmap_fits(pdev, num)) {
184 			sparse_base = 0;
185 			suffix = "_dense";
186 			nlen1 = 16;	/* resourceN_dense */
187 		}
188 	} else {
189 		sparse_base = hose->sparse_io_base;
190 		dense_base = hose->dense_io_base;
191 	}
192 
193 	if (sparse_base) {
194 		suffix = "_sparse";
195 		nlen1 = 17;
196 		if (dense_base) {
197 			nlen2 = 16;	/* resourceN_dense */
198 			res_count = 2;
199 		}
200 	}
201 
202 	attr = kzalloc(sizeof(*attr) * res_count + nlen1 + nlen2, GFP_ATOMIC);
203 	if (!attr)
204 		return -ENOMEM;
205 
206 	/* Create bwx, sparse or single dense file */
207 	attr_name = (char *)(attr + res_count);
208 	pdev->res_attr[num] = attr;
209 	retval = pci_create_one_attr(pdev, num, attr_name, suffix, attr,
210 				     sparse_base);
211 	if (retval || res_count == 1)
212 		return retval;
213 
214 	/* Create dense file */
215 	attr_name += nlen1;
216 	attr++;
217 	pdev->res_attr_wc[num] = attr;
218 	return pci_create_one_attr(pdev, num, attr_name, "_dense", attr, 0);
219 }
220 
221 /**
222  * pci_create_resource_files - create resource files in sysfs for @dev
223  * @dev: dev in question
224  *
225  * Walk the resources in @dev creating files for each resource available.
226  */
227 int pci_create_resource_files(struct pci_dev *pdev)
228 {
229 	int i;
230 	int retval;
231 
232 	/* Expose the PCI resources from this device as files */
233 	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
234 
235 		/* skip empty resources */
236 		if (!pci_resource_len(pdev, i))
237 			continue;
238 
239 		retval = pci_create_attr(pdev, i);
240 		if (retval) {
241 			pci_remove_resource_files(pdev);
242 			return retval;
243 		}
244 	}
245 	return 0;
246 }
247 
248 /* Legacy I/O bus mapping stuff. */
249 
250 static int __legacy_mmap_fits(struct pci_controller *hose,
251 			      struct vm_area_struct *vma,
252 			      unsigned long res_size, int sparse)
253 {
254 	unsigned long nr, start, size;
255 
256 	nr = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
257 	start = vma->vm_pgoff;
258 	size = ((res_size - 1) >> PAGE_SHIFT) + 1;
259 
260 	if (start < size && size - start >= nr)
261 		return 1;
262 	WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on hose %d "
263 		"(size 0x%08lx)\n",
264 		current->comm, sparse ? " sparse" : "", start, start + nr,
265 		hose->index, size);
266 	return 0;
267 }
268 
269 static inline int has_sparse(struct pci_controller *hose,
270 			     enum pci_mmap_state mmap_type)
271 {
272 	unsigned long base;
273 
274 	base = (mmap_type == pci_mmap_mem) ? hose->sparse_mem_base :
275 					     hose->sparse_io_base;
276 
277 	return base != 0;
278 }
279 
280 int pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma,
281 			       enum pci_mmap_state mmap_type)
282 {
283 	struct pci_controller *hose = bus->sysdata;
284 	int sparse = has_sparse(hose, mmap_type);
285 	unsigned long res_size;
286 
287 	res_size = (mmap_type == pci_mmap_mem) ? bus->legacy_mem->size :
288 						 bus->legacy_io->size;
289 	if (!__legacy_mmap_fits(hose, vma, res_size, sparse))
290 		return -EINVAL;
291 
292 	return hose_mmap_page_range(hose, vma, mmap_type, sparse);
293 }
294 
295 /**
296  * pci_adjust_legacy_attr - adjustment of legacy file attributes
297  * @b: bus to create files under
298  * @mmap_type: I/O port or memory
299  *
300  * Adjust file name and size for sparse mappings.
301  */
302 void pci_adjust_legacy_attr(struct pci_bus *bus, enum pci_mmap_state mmap_type)
303 {
304 	struct pci_controller *hose = bus->sysdata;
305 
306 	if (!has_sparse(hose, mmap_type))
307 		return;
308 
309 	if (mmap_type == pci_mmap_mem) {
310 		bus->legacy_mem->attr.name = "legacy_mem_sparse";
311 		bus->legacy_mem->size <<= 5;
312 	} else {
313 		bus->legacy_io->attr.name = "legacy_io_sparse";
314 		bus->legacy_io->size <<= 5;
315 	}
316 	return;
317 }
318 
319 /* Legacy I/O bus read/write functions */
320 int pci_legacy_read(struct pci_bus *bus, loff_t port, u32 *val, size_t size)
321 {
322 	struct pci_controller *hose = bus->sysdata;
323 
324 	port += hose->io_space->start;
325 
326 	switch(size) {
327 	case 1:
328 		*((u8 *)val) = inb(port);
329 		return 1;
330 	case 2:
331 		if (port & 1)
332 			return -EINVAL;
333 		*((u16 *)val) = inw(port);
334 		return 2;
335 	case 4:
336 		if (port & 3)
337 			return -EINVAL;
338 		*((u32 *)val) = inl(port);
339 		return 4;
340 	}
341 	return -EINVAL;
342 }
343 
344 int pci_legacy_write(struct pci_bus *bus, loff_t port, u32 val, size_t size)
345 {
346 	struct pci_controller *hose = bus->sysdata;
347 
348 	port += hose->io_space->start;
349 
350 	switch(size) {
351 	case 1:
352 		outb(port, val);
353 		return 1;
354 	case 2:
355 		if (port & 1)
356 			return -EINVAL;
357 		outw(port, val);
358 		return 2;
359 	case 4:
360 		if (port & 3)
361 			return -EINVAL;
362 		outl(port, val);
363 		return 4;
364 	}
365 	return -EINVAL;
366 }
367