arch/alpha/kernel/pci-sysfs.c

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