drivers/misc/swap_case.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * PCI emulation device which swaps the case of text
   4  *
   5  * Copyright (c) 2014 Google, Inc
   6  * Written by Simon Glass <sjg@chromium.org>
   7  */
   8
   9 #include <common.h>
  10 #include <dm.h>
  11 #include <errno.h>
  12 #include <pci.h>
  13 #include <asm/test.h>
  14 #include <linux/ctype.h>
  15
  16 /**
  17  * struct swap_case_platdata - platform data for this device
  18  *
  19  * @command:    Current PCI command value
  20  * @bar:        Current base address values
  21  */
  22 struct swap_case_platdata {
  23         u16 command;
  24         u32 bar[6];
  25 };
  26
  27 #define offset_to_barnum(offset)        \
  28                 (((offset) - PCI_BASE_ADDRESS_0) / sizeof(u32))
  29
  30 enum {
  31         MEM_TEXT_SIZE   = 0x100,
  32 };
  33
  34 enum swap_case_op {
  35         OP_TO_LOWER,
  36         OP_TO_UPPER,
  37         OP_SWAP,
  38 };
  39
  40 static struct pci_bar {
  41         int type;
  42         u32 size;
  43 } barinfo[] = {
  44         { PCI_BASE_ADDRESS_SPACE_IO, 1 },
  45         { PCI_BASE_ADDRESS_MEM_TYPE_32, MEM_TEXT_SIZE },
  46         { 0, 0 },
  47         { 0, 0 },
  48         { 0, 0 },
  49         { 0, 0 },
  50 };
  51
  52 struct swap_case_priv {
  53         enum swap_case_op op;
  54         char mem_text[MEM_TEXT_SIZE];
  55 };
  56
  57 static int sandbox_swap_case_get_devfn(struct udevice *dev)
  58 {
  59         struct pci_child_platdata *plat = dev_get_parent_platdata(dev);
  60
  61         return plat->devfn;
  62 }
  63
  64 static int sandbox_swap_case_read_config(struct udevice *emul, uint offset,
  65                                          ulong *valuep, enum pci_size_t size)
  66 {
  67         struct swap_case_platdata *plat = dev_get_platdata(emul);
  68
  69         switch (offset) {
  70         case PCI_COMMAND:
  71                 *valuep = plat->command;
  72                 break;
  73         case PCI_HEADER_TYPE:
  74                 *valuep = 0;
  75                 break;
  76         case PCI_VENDOR_ID:
  77                 *valuep = SANDBOX_PCI_VENDOR_ID;
  78                 break;
  79         case PCI_DEVICE_ID:
  80                 *valuep = SANDBOX_PCI_DEVICE_ID;
  81                 break;
  82         case PCI_CLASS_DEVICE:
  83                 if (size == PCI_SIZE_8) {
  84                         *valuep = SANDBOX_PCI_CLASS_SUB_CODE;
  85                 } else {
  86                         *valuep = (SANDBOX_PCI_CLASS_CODE << 8) |
  87                                         SANDBOX_PCI_CLASS_SUB_CODE;
  88                 }
  89                 break;
  90         case PCI_CLASS_CODE:
  91                 *valuep = SANDBOX_PCI_CLASS_CODE;
  92                 break;
  93         case PCI_BASE_ADDRESS_0:
  94         case PCI_BASE_ADDRESS_1:
  95         case PCI_BASE_ADDRESS_2:
  96         case PCI_BASE_ADDRESS_3:
  97         case PCI_BASE_ADDRESS_4:
  98         case PCI_BASE_ADDRESS_5: {
  99                 int barnum;
 100                 u32 *bar, result;
 101
 102                 barnum = offset_to_barnum(offset);
 103                 bar = &plat->bar[barnum];
 104
 105                 result = *bar;
 106                 if (*bar == 0xffffffff) {
 107                         if (barinfo[barnum].type) {
 108                                 result = (~(barinfo[barnum].size - 1) &
 109                                         PCI_BASE_ADDRESS_IO_MASK) |
 110                                         PCI_BASE_ADDRESS_SPACE_IO;
 111                         } else {
 112                                 result = (~(barinfo[barnum].size - 1) &
 113                                         PCI_BASE_ADDRESS_MEM_MASK) |
 114                                         PCI_BASE_ADDRESS_MEM_TYPE_32;
 115                         }
 116                 }
 117                 debug("r bar %d=%x\n", barnum, result);
 118                 *valuep = result;
 119                 break;
 120         }
 121         }
 122
 123         return 0;
 124 }
 125
 126 static int sandbox_swap_case_write_config(struct udevice *emul, uint offset,
 127                                           ulong value, enum pci_size_t size)
 128 {
 129         struct swap_case_platdata *plat = dev_get_platdata(emul);
 130
 131         switch (offset) {
 132         case PCI_COMMAND:
 133                 plat->command = value;
 134                 break;
 135         case PCI_BASE_ADDRESS_0:
 136         case PCI_BASE_ADDRESS_1: {
 137                 int barnum;
 138                 u32 *bar;
 139
 140                 barnum = offset_to_barnum(offset);
 141                 bar = &plat->bar[barnum];
 142
 143                 debug("w bar %d=%lx\n", barnum, value);
 144                 *bar = value;
 145                 /* space indicator (bit#0) is read-only */
 146                 *bar |= barinfo[barnum].type;
 147                 break;
 148         }
 149         }
 150
 151         return 0;
 152 }
 153
 154 static int sandbox_swap_case_find_bar(struct udevice *emul, unsigned int addr,
 155                                       int *barnump, unsigned int *offsetp)
 156 {
 157         struct swap_case_platdata *plat = dev_get_platdata(emul);
 158         int barnum;
 159
 160         for (barnum = 0; barnum < ARRAY_SIZE(barinfo); barnum++) {
 161                 unsigned int size = barinfo[barnum].size;
 162                 u32 base = plat->bar[barnum] & ~PCI_BASE_ADDRESS_SPACE;
 163
 164                 if (addr >= base && addr < base + size) {
 165                         *barnump = barnum;
 166                         *offsetp = addr - base;
 167                         return 0;
 168                 }
 169         }
 170         *barnump = -1;
 171
 172         return -ENOENT;
 173 }
 174
 175 static void sandbox_swap_case_do_op(enum swap_case_op op, char *str, int len)
 176 {
 177         for (; len > 0; len--, str++) {
 178                 switch (op) {
 179                 case OP_TO_UPPER:
 180                         *str = toupper(*str);
 181                         break;
 182                 case OP_TO_LOWER:
 183                         *str = tolower(*str);
 184                         break;
 185                 case OP_SWAP:
 186                         if (isupper(*str))
 187                                 *str = tolower(*str);
 188                         else
 189                                 *str = toupper(*str);
 190                         break;
 191                 }
 192         }
 193 }
 194
 195 int sandbox_swap_case_read_io(struct udevice *dev, unsigned int addr,
 196                               ulong *valuep, enum pci_size_t size)
 197 {
 198         struct swap_case_priv *priv = dev_get_priv(dev);
 199         unsigned int offset;
 200         int barnum;
 201         int ret;
 202
 203         ret = sandbox_swap_case_find_bar(dev, addr, &barnum, &offset);
 204         if (ret)
 205                 return ret;
 206
 207         if (barnum == 0 && offset == 0)
 208                 *valuep = (*valuep & ~0xff) | priv->op;
 209
 210         return 0;
 211 }
 212
 213 int sandbox_swap_case_write_io(struct udevice *dev, unsigned int addr,
 214                                ulong value, enum pci_size_t size)
 215 {
 216         struct swap_case_priv *priv = dev_get_priv(dev);
 217         unsigned int offset;
 218         int barnum;
 219         int ret;
 220
 221         ret = sandbox_swap_case_find_bar(dev, addr, &barnum, &offset);
 222         if (ret)
 223                 return ret;
 224         if (barnum == 0 && offset == 0)
 225                 priv->op = value;
 226
 227         return 0;
 228 }
 229
 230 static int sandbox_swap_case_map_physmem(struct udevice *dev,
 231                 phys_addr_t addr, unsigned long *lenp, void **ptrp)
 232 {
 233         struct swap_case_priv *priv = dev_get_priv(dev);
 234         unsigned int offset, avail;
 235         int barnum;
 236         int ret;
 237
 238         ret = sandbox_swap_case_find_bar(dev, addr, &barnum, &offset);
 239         if (ret)
 240                 return ret;
 241         if (barnum == 1) {
 242                 *ptrp = priv->mem_text + offset;
 243                 avail = barinfo[1].size - offset;
 244                 if (avail > barinfo[1].size)
 245                         *lenp = 0;
 246                 else
 247                         *lenp = min(*lenp, (ulong)avail);
 248
 249                 return 0;
 250         }
 251
 252         return -ENOENT;
 253 }
 254
 255 static int sandbox_swap_case_unmap_physmem(struct udevice *dev,
 256                                            const void *vaddr, unsigned long len)
 257 {
 258         struct swap_case_priv *priv = dev_get_priv(dev);
 259
 260         sandbox_swap_case_do_op(priv->op, (void *)vaddr, len);
 261
 262         return 0;
 263 }
 264
 265 struct dm_pci_emul_ops sandbox_swap_case_emul_ops = {
 266         .get_devfn = sandbox_swap_case_get_devfn,
 267         .read_config = sandbox_swap_case_read_config,
 268         .write_config = sandbox_swap_case_write_config,
 269         .read_io = sandbox_swap_case_read_io,
 270         .write_io = sandbox_swap_case_write_io,
 271         .map_physmem = sandbox_swap_case_map_physmem,
 272         .unmap_physmem = sandbox_swap_case_unmap_physmem,
 273 };
 274
 275 static const struct udevice_id sandbox_swap_case_ids[] = {
 276         { .compatible = "sandbox,swap-case" },
 277         { }
 278 };
 279
 280 U_BOOT_DRIVER(sandbox_swap_case_emul) = {
 281         .name           = "sandbox_swap_case_emul",
 282         .id             = UCLASS_PCI_EMUL,
 283         .of_match       = sandbox_swap_case_ids,
 284         .ops            = &sandbox_swap_case_emul_ops,
 285         .priv_auto_alloc_size = sizeof(struct swap_case_priv),
 286         .platdata_auto_alloc_size = sizeof(struct swap_case_platdata),
 287 };
 288
 289 static struct pci_device_id sandbox_swap_case_supported[] = {
 290         { PCI_VDEVICE(SANDBOX, SANDBOX_PCI_DEVICE_ID), SWAP_CASE_DRV_DATA },
 291         {},
 292 };
 293
 294 U_BOOT_PCI_DEVICE(sandbox_swap_case_emul, sandbox_swap_case_supported);