lib/logic_pio.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2017 Hisilicon Limited, All Rights Reserved.
   4  * Author: Gabriele Paoloni <gabriele.paoloni@huawei.com>
   5  * Author: Zhichang Yuan <yuanzhichang@hisilicon.com>
   6  *
   7  */
   8
   9 #define pr_fmt(fmt)     "LOGIC PIO: " fmt
  10
  11 #include <linux/of.h>
  12 #include <linux/io.h>
  13 #include <linux/logic_pio.h>
  14 #include <linux/mm.h>
  15 #include <linux/rculist.h>
  16 #include <linux/sizes.h>
  17 #include <linux/slab.h>
  18
  19 /* The unique hardware address list. */
  20 static LIST_HEAD(io_range_list);
  21 static DEFINE_MUTEX(io_range_mutex);
  22
  23 /**
  24  * logic_pio_register_range - register logical PIO range for a host
  25  * @new_range: pointer to the io range to be registered.
  26  *
  27  * returns 0 on success, the error code in case of failure
  28  *
  29  * Register a new io range node in the io range list.
  30  */
  31 int logic_pio_register_range(struct logic_pio_hwaddr *new_range)
  32 {
  33         struct logic_pio_hwaddr *range;
  34         resource_size_t start = new_range->hw_start;
  35         resource_size_t end = new_range->hw_start + new_range->size;
  36         resource_size_t allocated_mmio_size = 0;
  37         resource_size_t allocated_iio_size = MMIO_UPPER_LIMIT;
  38         int ret = 0;
  39
  40         if (!new_range || !new_range->fwnode || !new_range->size)
  41                 return -EINVAL;
  42
  43         mutex_lock(&io_range_mutex);
  44         list_for_each_entry_rcu(range, &io_range_list, list) {
  45                 if (range->fwnode == new_range->fwnode) {
  46                         /* range already there */
  47                         ret = -EFAULT;
  48                         goto end_register;
  49                 }
  50                 if (range->flags == PIO_CPU_MMIO &&
  51                                 new_range->flags == PIO_CPU_MMIO) {
  52                         /* for MMIO ranges we need to check for overlap */
  53                         if (start >= range->hw_start + range->size ||
  54                             end < range->hw_start)
  55                                 allocated_mmio_size += range->size;
  56                         else {
  57                                 ret = -EFAULT;
  58                                 goto end_register;
  59                         }
  60                 } else if (range->flags == PIO_INDIRECT &&
  61                            new_range->flags == PIO_INDIRECT) {
  62                         allocated_iio_size += range->size;
  63                 }
  64         }
  65
  66         /* range not registered yet, check for available space */
  67         if (new_range->flags == PIO_CPU_MMIO) {
  68                 if (allocated_mmio_size + new_range->size - 1 >
  69                         MMIO_UPPER_LIMIT) {
  70                         /* if it's too big check if 64K space can be reserved */
  71                         if (allocated_mmio_size + SZ_64K - 1 >
  72                         MMIO_UPPER_LIMIT) {
  73                                 ret = -E2BIG;
  74                                 goto end_register;
  75                         }
  76                         new_range->size = SZ_64K;
  77                         pr_warn("Requested IO range too big, new size set to 64K\n");
  78                 }
  79                 new_range->io_start = allocated_mmio_size;
  80         } else if (new_range->flags == PIO_INDIRECT) {
  81                 if (allocated_iio_size + new_range->size - 1 >
  82                     IO_SPACE_LIMIT) {
  83                         ret = -E2BIG;
  84                         goto end_register;
  85                 }
  86                 new_range->io_start = allocated_iio_size;
  87         } else {
  88                 /* invalid flag */
  89                 ret = -EINVAL;
  90                 goto end_register;
  91         }
  92
  93         list_add_tail_rcu(&new_range->list, &io_range_list);
  94
  95 end_register:
  96         mutex_unlock(&io_range_mutex);
  97         return ret;
  98 }
  99
 100 /**
 101  * find_io_range_by_fwnode - find logical PIO range for given FW node
 102  * @fwnode: FW node handle associated with logical PIO range
 103  *
 104  * Returns pointer to node on success, NULL otherwise
 105  *
 106  * Traverse the io_range_list to find the registered node whose device node
 107  * and/or physical IO address match to.
 108  */
 109 struct logic_pio_hwaddr *find_io_range_by_fwnode(struct fwnode_handle *fwnode)
 110 {
 111         struct logic_pio_hwaddr *range;
 112
 113         list_for_each_entry_rcu(range, &io_range_list, list) {
 114                 if (range->fwnode == fwnode)
 115                         return range;
 116         }
 117         return NULL;
 118 }
 119
 120 /* Return a registered range given an input PIO token */
 121 static struct logic_pio_hwaddr *find_io_range(unsigned long pio)
 122 {
 123         struct logic_pio_hwaddr *range;
 124
 125         list_for_each_entry_rcu(range, &io_range_list, list) {
 126                 if (pio >= range->io_start &&
 127                     pio < range->io_start + range->size)
 128                         return range;
 129         }
 130         pr_err("PIO entry token invalid\n");
 131         return NULL;
 132 }
 133
 134 /**
 135  * logic_pio_to_hwaddr - translate logical PIO to HW address
 136  * @pio: logical PIO value
 137  *
 138  * Returns HW address if valid, -1 otherwise
 139  *
 140  * Translate the input logical pio to the corresponding hardware address.
 141  * The input pio should be unique in the whole logical PIO space.
 142  */
 143 resource_size_t logic_pio_to_hwaddr(unsigned long pio)
 144 {
 145         struct logic_pio_hwaddr *range;
 146         resource_size_t hwaddr = -1;
 147
 148         range = find_io_range(pio);
 149         if (range)
 150                 hwaddr = range->hw_start + pio - range->io_start;
 151
 152         return hwaddr;
 153 }
 154
 155 /**
 156  * logic_pio_trans_hwaddr - translate HW address to logical PIO
 157  * @fwnode: FW node reference for the host
 158  * @addr: Host-relative HW address
 159  * @size: size to translate
 160  *
 161  * Returns Logical PIO value if successful, -1 otherwise
 162  */
 163 unsigned long
 164 logic_pio_trans_hwaddr(struct fwnode_handle *fwnode, resource_size_t addr,
 165                        resource_size_t size)
 166 {
 167         struct logic_pio_hwaddr *range;
 168
 169         range = find_io_range_by_fwnode(fwnode);
 170         if (!range || range->flags == PIO_CPU_MMIO) {
 171                 pr_err("range not found or invalid\n");
 172                 return -1;
 173         }
 174         if (range->size < size) {
 175                 pr_err("resource size %pa cannot fit in IO range size %pa\n",
 176                        &size, &range->size);
 177                 return -1;
 178         }
 179         return addr - range->hw_start + range->io_start;
 180 }
 181
 182 unsigned long
 183 logic_pio_trans_cpuaddr(resource_size_t addr)
 184 {
 185         struct logic_pio_hwaddr *range;
 186
 187         list_for_each_entry_rcu(range, &io_range_list, list) {
 188                 if (range->flags != PIO_CPU_MMIO)
 189                         continue;
 190                 if (addr >= range->hw_start &&
 191                     addr < range->hw_start + range->size)
 192                         return addr - range->hw_start +
 193                                 range->io_start;
 194         }
 195         pr_err("addr not registered in io_range_list\n");
 196         return -1;
 197 }
 198
 199 #if defined(CONFIG_INDIRECT_PIO) && defined(PCI_IOBASE)
 200 #define BUILD_LOGIC_IO(bw, type)                                        \
 201 type logic_in##bw(unsigned long addr)                                   \
 202 {                                                                       \
 203         type ret = -1;                                                  \
 204                                                                         \
 205         if (addr < MMIO_UPPER_LIMIT) {                                  \
 206                 ret = read##bw(PCI_IOBASE + addr);                      \
 207         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
 208                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
 209                                                                         \
 210                 if (entry && entry->ops)                                \
 211                         ret = entry->ops->in(entry->hostdata,           \
 212                                         addr, sizeof(type));            \
 213                 else                                                    \
 214                         WARN_ON_ONCE(1);                                \
 215         }                                                               \
 216         return ret;                                                     \
 217 }                                                                       \
 218                                                                         \
 219 void logic_out##bw(type value, unsigned long addr)                      \
 220 {                                                                       \
 221         if (addr < MMIO_UPPER_LIMIT) {                                  \
 222                 write##bw(value, PCI_IOBASE + addr);                    \
 223         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
 224                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
 225                                                                         \
 226                 if (entry && entry->ops)                                \
 227                         entry->ops->out(entry->hostdata,                \
 228                                         addr, value, sizeof(type));     \
 229                 else                                                    \
 230                         WARN_ON_ONCE(1);                                \
 231         }                                                               \
 232 }                                                                       \
 233                                                                         \
 234 void logic_ins##bw(unsigned long addr, void *buffer,            \
 235                    unsigned int count)                                  \
 236 {                                                                       \
 237         if (addr < MMIO_UPPER_LIMIT) {                                  \
 238                 reads##bw(PCI_IOBASE + addr, buffer, count);            \
 239         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
 240                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
 241                                                                         \
 242                 if (entry && entry->ops)                                \
 243                         entry->ops->ins(entry->hostdata,                \
 244                                 addr, buffer, sizeof(type), count);     \
 245                 else                                                    \
 246                         WARN_ON_ONCE(1);                                \
 247         }                                                               \
 248                                                                         \
 249 }                                                                       \
 250                                                                         \
 251 void logic_outs##bw(unsigned long addr, const void *buffer,             \
 252                     unsigned int count)                                 \
 253 {                                                                       \
 254         if (addr < MMIO_UPPER_LIMIT) {                                  \
 255                 writes##bw(PCI_IOBASE + addr, buffer, count);           \
 256         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
 257                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
 258                                                                         \
 259                 if (entry && entry->ops)                                \
 260                         entry->ops->outs(entry->hostdata,               \
 261                                 addr, buffer, sizeof(type), count);     \
 262                 else                                                    \
 263                         WARN_ON_ONCE(1);                                \
 264         }                                                               \
 265 }
 266
 267 BUILD_LOGIC_IO(b, u8)
 268 EXPORT_SYMBOL(logic_inb);
 269 EXPORT_SYMBOL(logic_insb);
 270 EXPORT_SYMBOL(logic_outb);
 271 EXPORT_SYMBOL(logic_outsb);
 272
 273 BUILD_LOGIC_IO(w, u16)
 274 EXPORT_SYMBOL(logic_inw);
 275 EXPORT_SYMBOL(logic_insw);
 276 EXPORT_SYMBOL(logic_outw);
 277 EXPORT_SYMBOL(logic_outsw);
 278
 279 BUILD_LOGIC_IO(l, u32)
 280 EXPORT_SYMBOL(logic_inl);
 281 EXPORT_SYMBOL(logic_insl);
 282 EXPORT_SYMBOL(logic_outl);
 283 EXPORT_SYMBOL(logic_outsl);
 284
 285 #endif /* CONFIG_INDIRECT_PIO && PCI_IOBASE */