1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * arch/alpha/kernel/pci-sysfs.c
4 *
5 * Copyright (C) 2009 Ivan Kokshaysky
6 *
7 * Alpha PCI resource files.
8 *
9 * Loosely based on generic HAVE_PCI_MMAP implementation in
10 * drivers/pci/pci-sysfs.c
11 */
12
13 #include <linux/sched.h>
14 #include <linux/stat.h>
15 #include <linux/slab.h>
16 #include <linux/pci.h>
17
hose_mmap_page_range(struct pci_controller * hose,struct vm_area_struct * vma,enum pci_mmap_state mmap_type,int sparse)18 static int hose_mmap_page_range(struct pci_controller *hose,
19 struct vm_area_struct *vma,
20 enum pci_mmap_state mmap_type, int sparse)
21 {
22 unsigned long base;
23
24 if (mmap_type == pci_mmap_mem)
25 base = sparse ? hose->sparse_mem_base : hose->dense_mem_base;
26 else
27 base = sparse ? hose->sparse_io_base : hose->dense_io_base;
28
29 vma->vm_pgoff += base >> PAGE_SHIFT;
30
31 return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
32 vma->vm_end - vma->vm_start,
33 vma->vm_page_prot);
34 }
35
__pci_mmap_fits(struct pci_dev * pdev,int num,struct vm_area_struct * vma,int sparse)36 static int __pci_mmap_fits(struct pci_dev *pdev, int num,
37 struct vm_area_struct *vma, int sparse)
38 {
39 unsigned long nr, start, size;
40 int shift = sparse ? 5 : 0;
41
42 nr = vma_pages(vma);
43 start = vma->vm_pgoff;
44 size = ((pci_resource_len(pdev, num) - 1) >> (PAGE_SHIFT - shift)) + 1;
45
46 if (start < size && size - start >= nr)
47 return 1;
48 WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on %s BAR %d "
49 "(size 0x%08lx)\n",
50 current->comm, sparse ? " sparse" : "", start, start + nr,
51 pci_name(pdev), num, size);
52 return 0;
53 }
54
55 /**
56 * pci_mmap_resource - map a PCI resource into user memory space
57 * @kobj: kobject for mapping
58 * @attr: struct bin_attribute for the file being mapped
59 * @vma: struct vm_area_struct passed into the mmap
60 * @sparse: address space type
61 *
62 * Use the bus mapping routines to map a PCI resource into userspace.
63 *
64 * Return: %0 on success, negative error code otherwise
65 */
pci_mmap_resource(struct kobject * kobj,struct bin_attribute * attr,struct vm_area_struct * vma,int sparse)66 static int pci_mmap_resource(struct kobject *kobj,
67 struct bin_attribute *attr,
68 struct vm_area_struct *vma, int sparse)
69 {
70 struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
71 struct resource *res = attr->private;
72 enum pci_mmap_state mmap_type;
73 struct pci_bus_region bar;
74 int i;
75
76 for (i = 0; i < PCI_STD_NUM_BARS; i++)
77 if (res == &pdev->resource[i])
78 break;
79 if (i >= PCI_STD_NUM_BARS)
80 return -ENODEV;
81
82 if (res->flags & IORESOURCE_MEM && iomem_is_exclusive(res->start))
83 return -EINVAL;
84
85 if (!__pci_mmap_fits(pdev, i, vma, sparse))
86 return -EINVAL;
87
88 pcibios_resource_to_bus(pdev->bus, &bar, res);
89 vma->vm_pgoff += bar.start >> (PAGE_SHIFT - (sparse ? 5 : 0));
90 mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
91
92 return hose_mmap_page_range(pdev->sysdata, vma, mmap_type, sparse);
93 }
94
pci_mmap_resource_sparse(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,struct vm_area_struct * vma)95 static int pci_mmap_resource_sparse(struct file *filp, struct kobject *kobj,
96 struct bin_attribute *attr,
97 struct vm_area_struct *vma)
98 {
99 return pci_mmap_resource(kobj, attr, vma, 1);
100 }
101
pci_mmap_resource_dense(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,struct vm_area_struct * vma)102 static int pci_mmap_resource_dense(struct file *filp, struct kobject *kobj,
103 struct bin_attribute *attr,
104 struct vm_area_struct *vma)
105 {
106 return pci_mmap_resource(kobj, attr, vma, 0);
107 }
108
109 /**
110 * pci_remove_resource_files - cleanup resource files
111 * @pdev: pci_dev to cleanup
112 *
113 * If we created resource files for @dev, remove them from sysfs and
114 * free their resources.
115 */
pci_remove_resource_files(struct pci_dev * pdev)116 void pci_remove_resource_files(struct pci_dev *pdev)
117 {
118 int i;
119
120 for (i = 0; i < PCI_STD_NUM_BARS; i++) {
121 struct bin_attribute *res_attr;
122
123 res_attr = pdev->res_attr[i];
124 if (res_attr) {
125 sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
126 kfree(res_attr);
127 }
128
129 res_attr = pdev->res_attr_wc[i];
130 if (res_attr) {
131 sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
132 kfree(res_attr);
133 }
134 }
135 }
136
sparse_mem_mmap_fits(struct pci_dev * pdev,int num)137 static int sparse_mem_mmap_fits(struct pci_dev *pdev, int num)
138 {
139 struct pci_bus_region bar;
140 struct pci_controller *hose = pdev->sysdata;
141 long dense_offset;
142 unsigned long sparse_size;
143
144 pcibios_resource_to_bus(pdev->bus, &bar, &pdev->resource[num]);
145
146 /* All core logic chips have 4G sparse address space, except
147 CIA which has 16G (see xxx_SPARSE_MEM and xxx_DENSE_MEM
148 definitions in asm/core_xxx.h files). This corresponds
149 to 128M or 512M of the bus space. */
150 dense_offset = (long)(hose->dense_mem_base - hose->sparse_mem_base);
151 sparse_size = dense_offset >= 0x400000000UL ? 0x20000000 : 0x8000000;
152
153 return bar.end < sparse_size;
154 }
155
pci_create_one_attr(struct pci_dev * pdev,int num,char * name,char * suffix,struct bin_attribute * res_attr,unsigned long sparse)156 static int pci_create_one_attr(struct pci_dev *pdev, int num, char *name,
157 char *suffix, struct bin_attribute *res_attr,
158 unsigned long sparse)
159 {
160 size_t size = pci_resource_len(pdev, num);
161
162 sprintf(name, "resource%d%s", num, suffix);
163 res_attr->mmap = sparse ? pci_mmap_resource_sparse :
164 pci_mmap_resource_dense;
165 res_attr->attr.name = name;
166 res_attr->attr.mode = S_IRUSR | S_IWUSR;
167 res_attr->size = sparse ? size << 5 : size;
168 res_attr->private = &pdev->resource[num];
169 return sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
170 }
171
pci_create_attr(struct pci_dev * pdev,int num)172 static int pci_create_attr(struct pci_dev *pdev, int num)
173 {
174 /* allocate attribute structure, piggyback attribute name */
175 int retval, nlen1, nlen2 = 0, res_count = 1;
176 unsigned long sparse_base, dense_base;
177 struct bin_attribute *attr;
178 struct pci_controller *hose = pdev->sysdata;
179 char *suffix, *attr_name;
180
181 suffix = ""; /* Assume bwx machine, normal resourceN files. */
182 nlen1 = 10;
183
184 if (pdev->resource[num].flags & IORESOURCE_MEM) {
185 sparse_base = hose->sparse_mem_base;
186 dense_base = hose->dense_mem_base;
187 if (sparse_base && !sparse_mem_mmap_fits(pdev, num)) {
188 sparse_base = 0;
189 suffix = "_dense";
190 nlen1 = 16; /* resourceN_dense */
191 }
192 } else {
193 sparse_base = hose->sparse_io_base;
194 dense_base = hose->dense_io_base;
195 }
196
197 if (sparse_base) {
198 suffix = "_sparse";
199 nlen1 = 17;
200 if (dense_base) {
201 nlen2 = 16; /* resourceN_dense */
202 res_count = 2;
203 }
204 }
205
206 attr = kzalloc(sizeof(*attr) * res_count + nlen1 + nlen2, GFP_ATOMIC);
207 if (!attr)
208 return -ENOMEM;
209
210 /* Create bwx, sparse or single dense file */
211 attr_name = (char *)(attr + res_count);
212 pdev->res_attr[num] = attr;
213 retval = pci_create_one_attr(pdev, num, attr_name, suffix, attr,
214 sparse_base);
215 if (retval || res_count == 1)
216 return retval;
217
218 /* Create dense file */
219 attr_name += nlen1;
220 attr++;
221 pdev->res_attr_wc[num] = attr;
222 return pci_create_one_attr(pdev, num, attr_name, "_dense", attr, 0);
223 }
224
225 /**
226 * pci_create_resource_files - create resource files in sysfs for @pdev
227 * @pdev: pci_dev in question
228 *
229 * Walk the resources in @dev creating files for each resource available.
230 *
231 * Return: %0 on success, or negative error code
232 */
pci_create_resource_files(struct pci_dev * pdev)233 int pci_create_resource_files(struct pci_dev *pdev)
234 {
235 int i;
236 int retval;
237
238 /* Expose the PCI resources from this device as files */
239 for (i = 0; i < PCI_STD_NUM_BARS; i++) {
240
241 /* skip empty resources */
242 if (!pci_resource_len(pdev, i))
243 continue;
244
245 retval = pci_create_attr(pdev, i);
246 if (retval) {
247 pci_remove_resource_files(pdev);
248 return retval;
249 }
250 }
251 return 0;
252 }
253
254 /* Legacy I/O bus mapping stuff. */
255
__legacy_mmap_fits(struct pci_controller * hose,struct vm_area_struct * vma,unsigned long res_size,int sparse)256 static int __legacy_mmap_fits(struct pci_controller *hose,
257 struct vm_area_struct *vma,
258 unsigned long res_size, int sparse)
259 {
260 unsigned long nr, start, size;
261
262 nr = vma_pages(vma);
263 start = vma->vm_pgoff;
264 size = ((res_size - 1) >> PAGE_SHIFT) + 1;
265
266 if (start < size && size - start >= nr)
267 return 1;
268 WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on hose %d "
269 "(size 0x%08lx)\n",
270 current->comm, sparse ? " sparse" : "", start, start + nr,
271 hose->index, size);
272 return 0;
273 }
274
has_sparse(struct pci_controller * hose,enum pci_mmap_state mmap_type)275 static inline int has_sparse(struct pci_controller *hose,
276 enum pci_mmap_state mmap_type)
277 {
278 unsigned long base;
279
280 base = (mmap_type == pci_mmap_mem) ? hose->sparse_mem_base :
281 hose->sparse_io_base;
282
283 return base != 0;
284 }
285
pci_mmap_legacy_page_range(struct pci_bus * bus,struct vm_area_struct * vma,enum pci_mmap_state mmap_type)286 int pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma,
287 enum pci_mmap_state mmap_type)
288 {
289 struct pci_controller *hose = bus->sysdata;
290 int sparse = has_sparse(hose, mmap_type);
291 unsigned long res_size;
292
293 res_size = (mmap_type == pci_mmap_mem) ? bus->legacy_mem->size :
294 bus->legacy_io->size;
295 if (!__legacy_mmap_fits(hose, vma, res_size, sparse))
296 return -EINVAL;
297
298 return hose_mmap_page_range(hose, vma, mmap_type, sparse);
299 }
300
301 /**
302 * pci_adjust_legacy_attr - adjustment of legacy file attributes
303 * @bus: bus to create files under
304 * @mmap_type: I/O port or memory
305 *
306 * Adjust file name and size for sparse mappings.
307 */
pci_adjust_legacy_attr(struct pci_bus * bus,enum pci_mmap_state mmap_type)308 void pci_adjust_legacy_attr(struct pci_bus *bus, enum pci_mmap_state mmap_type)
309 {
310 struct pci_controller *hose = bus->sysdata;
311
312 if (!has_sparse(hose, mmap_type))
313 return;
314
315 if (mmap_type == pci_mmap_mem) {
316 bus->legacy_mem->attr.name = "legacy_mem_sparse";
317 bus->legacy_mem->size <<= 5;
318 } else {
319 bus->legacy_io->attr.name = "legacy_io_sparse";
320 bus->legacy_io->size <<= 5;
321 }
322 return;
323 }
324
325 /* Legacy I/O bus read/write functions */
pci_legacy_read(struct pci_bus * bus,loff_t port,u32 * val,size_t size)326 int pci_legacy_read(struct pci_bus *bus, loff_t port, u32 *val, size_t size)
327 {
328 struct pci_controller *hose = bus->sysdata;
329
330 port += hose->io_space->start;
331
332 switch(size) {
333 case 1:
334 *((u8 *)val) = inb(port);
335 return 1;
336 case 2:
337 if (port & 1)
338 return -EINVAL;
339 *((u16 *)val) = inw(port);
340 return 2;
341 case 4:
342 if (port & 3)
343 return -EINVAL;
344 *((u32 *)val) = inl(port);
345 return 4;
346 }
347 return -EINVAL;
348 }
349
pci_legacy_write(struct pci_bus * bus,loff_t port,u32 val,size_t size)350 int pci_legacy_write(struct pci_bus *bus, loff_t port, u32 val, size_t size)
351 {
352 struct pci_controller *hose = bus->sysdata;
353
354 port += hose->io_space->start;
355
356 switch(size) {
357 case 1:
358 outb(port, val);
359 return 1;
360 case 2:
361 if (port & 1)
362 return -EINVAL;
363 outw(port, val);
364 return 2;
365 case 4:
366 if (port & 3)
367 return -EINVAL;
368 outl(port, val);
369 return 4;
370 }
371 return -EINVAL;
372 }
373