Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
[sfrench/cifs-2.6.git] / 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 #define pr_fmt(fmt)     "LOGIC PIO: " fmt
9
10 #include <linux/of.h>
11 #include <linux/io.h>
12 #include <linux/logic_pio.h>
13 #include <linux/mm.h>
14 #include <linux/rculist.h>
15 #include <linux/sizes.h>
16 #include <linux/slab.h>
17
18 /* The unique hardware address list */
19 static LIST_HEAD(io_range_list);
20 static DEFINE_MUTEX(io_range_mutex);
21
22 /* Consider a kernel general helper for this */
23 #define in_range(b, first, len)        ((b) >= (first) && (b) < (first) + (len))
24
25 /**
26  * logic_pio_register_range - register logical PIO range for a host
27  * @new_range: pointer to the IO range to be registered.
28  *
29  * Returns 0 on success, the error code in case of failure.
30  *
31  * Register a new IO range node in the IO range list.
32  */
33 int logic_pio_register_range(struct logic_pio_hwaddr *new_range)
34 {
35         struct logic_pio_hwaddr *range;
36         resource_size_t start;
37         resource_size_t end;
38         resource_size_t mmio_end = 0;
39         resource_size_t iio_sz = MMIO_UPPER_LIMIT;
40         int ret = 0;
41
42         if (!new_range || !new_range->fwnode || !new_range->size)
43                 return -EINVAL;
44
45         start = new_range->hw_start;
46         end = new_range->hw_start + new_range->size;
47
48         mutex_lock(&io_range_mutex);
49         list_for_each_entry(range, &io_range_list, list) {
50                 if (range->fwnode == new_range->fwnode) {
51                         /* range already there */
52                         goto end_register;
53                 }
54                 if (range->flags == LOGIC_PIO_CPU_MMIO &&
55                     new_range->flags == LOGIC_PIO_CPU_MMIO) {
56                         /* for MMIO ranges we need to check for overlap */
57                         if (start >= range->hw_start + range->size ||
58                             end < range->hw_start) {
59                                 mmio_end = range->io_start + range->size;
60                         } else {
61                                 ret = -EFAULT;
62                                 goto end_register;
63                         }
64                 } else if (range->flags == LOGIC_PIO_INDIRECT &&
65                            new_range->flags == LOGIC_PIO_INDIRECT) {
66                         iio_sz += range->size;
67                 }
68         }
69
70         /* range not registered yet, check for available space */
71         if (new_range->flags == LOGIC_PIO_CPU_MMIO) {
72                 if (mmio_end + new_range->size - 1 > MMIO_UPPER_LIMIT) {
73                         /* if it's too big check if 64K space can be reserved */
74                         if (mmio_end + SZ_64K - 1 > MMIO_UPPER_LIMIT) {
75                                 ret = -E2BIG;
76                                 goto end_register;
77                         }
78                         new_range->size = SZ_64K;
79                         pr_warn("Requested IO range too big, new size set to 64K\n");
80                 }
81                 new_range->io_start = mmio_end;
82         } else if (new_range->flags == LOGIC_PIO_INDIRECT) {
83                 if (iio_sz + new_range->size - 1 > IO_SPACE_LIMIT) {
84                         ret = -E2BIG;
85                         goto end_register;
86                 }
87                 new_range->io_start = iio_sz;
88         } else {
89                 /* invalid flag */
90                 ret = -EINVAL;
91                 goto end_register;
92         }
93
94         list_add_tail_rcu(&new_range->list, &io_range_list);
95
96 end_register:
97         mutex_unlock(&io_range_mutex);
98         return ret;
99 }
100
101 /**
102  * logic_pio_unregister_range - unregister a logical PIO range for a host
103  * @range: pointer to the IO range which has been already registered.
104  *
105  * Unregister a previously-registered IO range node.
106  */
107 void logic_pio_unregister_range(struct logic_pio_hwaddr *range)
108 {
109         mutex_lock(&io_range_mutex);
110         list_del_rcu(&range->list);
111         mutex_unlock(&io_range_mutex);
112         synchronize_rcu();
113 }
114
115 /**
116  * find_io_range_by_fwnode - find logical PIO range for given FW node
117  * @fwnode: FW node handle associated with logical PIO range
118  *
119  * Returns pointer to node on success, NULL otherwise.
120  *
121  * Traverse the io_range_list to find the registered node for @fwnode.
122  */
123 struct logic_pio_hwaddr *find_io_range_by_fwnode(struct fwnode_handle *fwnode)
124 {
125         struct logic_pio_hwaddr *range, *found_range = NULL;
126
127         rcu_read_lock();
128         list_for_each_entry_rcu(range, &io_range_list, list) {
129                 if (range->fwnode == fwnode) {
130                         found_range = range;
131                         break;
132                 }
133         }
134         rcu_read_unlock();
135
136         return found_range;
137 }
138
139 /* Return a registered range given an input PIO token */
140 static struct logic_pio_hwaddr *find_io_range(unsigned long pio)
141 {
142         struct logic_pio_hwaddr *range, *found_range = NULL;
143
144         rcu_read_lock();
145         list_for_each_entry_rcu(range, &io_range_list, list) {
146                 if (in_range(pio, range->io_start, range->size)) {
147                         found_range = range;
148                         break;
149                 }
150         }
151         rcu_read_unlock();
152
153         if (!found_range)
154                 pr_err("PIO entry token 0x%lx invalid\n", pio);
155
156         return found_range;
157 }
158
159 /**
160  * logic_pio_to_hwaddr - translate logical PIO to HW address
161  * @pio: logical PIO value
162  *
163  * Returns HW address if valid, ~0 otherwise.
164  *
165  * Translate the input logical PIO to the corresponding hardware address.
166  * The input PIO should be unique in the whole logical PIO space.
167  */
168 resource_size_t logic_pio_to_hwaddr(unsigned long pio)
169 {
170         struct logic_pio_hwaddr *range;
171
172         range = find_io_range(pio);
173         if (range)
174                 return range->hw_start + pio - range->io_start;
175
176         return (resource_size_t)~0;
177 }
178
179 /**
180  * logic_pio_trans_hwaddr - translate HW address to logical PIO
181  * @fwnode: FW node reference for the host
182  * @addr: Host-relative HW address
183  * @size: size to translate
184  *
185  * Returns Logical PIO value if successful, ~0UL otherwise
186  */
187 unsigned long logic_pio_trans_hwaddr(struct fwnode_handle *fwnode,
188                                      resource_size_t addr, resource_size_t size)
189 {
190         struct logic_pio_hwaddr *range;
191
192         range = find_io_range_by_fwnode(fwnode);
193         if (!range || range->flags == LOGIC_PIO_CPU_MMIO) {
194                 pr_err("IO range not found or invalid\n");
195                 return ~0UL;
196         }
197         if (range->size < size) {
198                 pr_err("resource size %pa cannot fit in IO range size %pa\n",
199                        &size, &range->size);
200                 return ~0UL;
201         }
202         return addr - range->hw_start + range->io_start;
203 }
204
205 unsigned long logic_pio_trans_cpuaddr(resource_size_t addr)
206 {
207         struct logic_pio_hwaddr *range;
208
209         rcu_read_lock();
210         list_for_each_entry_rcu(range, &io_range_list, list) {
211                 if (range->flags != LOGIC_PIO_CPU_MMIO)
212                         continue;
213                 if (in_range(addr, range->hw_start, range->size)) {
214                         unsigned long cpuaddr;
215
216                         cpuaddr = addr - range->hw_start + range->io_start;
217
218                         rcu_read_unlock();
219                         return cpuaddr;
220                 }
221         }
222         rcu_read_unlock();
223
224         pr_err("addr %pa not registered in io_range_list\n", &addr);
225
226         return ~0UL;
227 }
228
229 #if defined(CONFIG_INDIRECT_PIO) && defined(PCI_IOBASE)
230 #define BUILD_LOGIC_IO(bw, type)                                        \
231 type logic_in##bw(unsigned long addr)                                   \
232 {                                                                       \
233         type ret = (type)~0;                                            \
234                                                                         \
235         if (addr < MMIO_UPPER_LIMIT) {                                  \
236                 ret = read##bw(PCI_IOBASE + addr);                      \
237         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
238                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
239                                                                         \
240                 if (entry && entry->ops)                                \
241                         ret = entry->ops->in(entry->hostdata,           \
242                                         addr, sizeof(type));            \
243                 else                                                    \
244                         WARN_ON_ONCE(1);                                \
245         }                                                               \
246         return ret;                                                     \
247 }                                                                       \
248                                                                         \
249 void logic_out##bw(type value, unsigned long addr)                      \
250 {                                                                       \
251         if (addr < MMIO_UPPER_LIMIT) {                                  \
252                 write##bw(value, PCI_IOBASE + addr);                    \
253         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
254                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
255                                                                         \
256                 if (entry && entry->ops)                                \
257                         entry->ops->out(entry->hostdata,                \
258                                         addr, value, sizeof(type));     \
259                 else                                                    \
260                         WARN_ON_ONCE(1);                                \
261         }                                                               \
262 }                                                                       \
263                                                                         \
264 void logic_ins##bw(unsigned long addr, void *buffer,            \
265                    unsigned int count)                                  \
266 {                                                                       \
267         if (addr < MMIO_UPPER_LIMIT) {                                  \
268                 reads##bw(PCI_IOBASE + addr, buffer, count);            \
269         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
270                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
271                                                                         \
272                 if (entry && entry->ops)                                \
273                         entry->ops->ins(entry->hostdata,                \
274                                 addr, buffer, sizeof(type), count);     \
275                 else                                                    \
276                         WARN_ON_ONCE(1);                                \
277         }                                                               \
278                                                                         \
279 }                                                                       \
280                                                                         \
281 void logic_outs##bw(unsigned long addr, const void *buffer,             \
282                     unsigned int count)                                 \
283 {                                                                       \
284         if (addr < MMIO_UPPER_LIMIT) {                                  \
285                 writes##bw(PCI_IOBASE + addr, buffer, count);           \
286         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
287                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
288                                                                         \
289                 if (entry && entry->ops)                                \
290                         entry->ops->outs(entry->hostdata,               \
291                                 addr, buffer, sizeof(type), count);     \
292                 else                                                    \
293                         WARN_ON_ONCE(1);                                \
294         }                                                               \
295 }
296
297 BUILD_LOGIC_IO(b, u8)
298 EXPORT_SYMBOL(logic_inb);
299 EXPORT_SYMBOL(logic_insb);
300 EXPORT_SYMBOL(logic_outb);
301 EXPORT_SYMBOL(logic_outsb);
302
303 BUILD_LOGIC_IO(w, u16)
304 EXPORT_SYMBOL(logic_inw);
305 EXPORT_SYMBOL(logic_insw);
306 EXPORT_SYMBOL(logic_outw);
307 EXPORT_SYMBOL(logic_outsw);
308
309 BUILD_LOGIC_IO(l, u32)
310 EXPORT_SYMBOL(logic_inl);
311 EXPORT_SYMBOL(logic_insl);
312 EXPORT_SYMBOL(logic_outl);
313 EXPORT_SYMBOL(logic_outsl);
314
315 #endif /* CONFIG_INDIRECT_PIO && PCI_IOBASE */