1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * ioport.c: Simple io mapping allocator.
4 *
5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
6 * Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx)
7 *
8 * 1996: sparc_free_io, 1999: ioremap()/iounmap() by Pete Zaitcev.
9 *
10 * 2000/01/29
11 * <rth> zait: as long as pci_alloc_consistent produces something addressable,
12 * things are ok.
13 * <zaitcev> rth: no, it is relevant, because get_free_pages returns you a
14 * pointer into the big page mapping
15 * <rth> zait: so what?
16 * <rth> zait: remap_it_my_way(virt_to_phys(get_free_page()))
17 * <zaitcev> Hmm
18 * <zaitcev> Suppose I did this remap_it_my_way(virt_to_phys(get_free_page())).
19 * So far so good.
20 * <zaitcev> Now, driver calls pci_free_consistent(with result of
21 * remap_it_my_way()).
22 * <zaitcev> How do you find the address to pass to free_pages()?
23 * <rth> zait: walk the page tables? It's only two or three level after all.
24 * <rth> zait: you have to walk them anyway to remove the mapping.
25 * <zaitcev> Hmm
26 * <zaitcev> Sounds reasonable
27 */
28
29 #include <linux/module.h>
30 #include <linux/sched.h>
31 #include <linux/kernel.h>
32 #include <linux/errno.h>
33 #include <linux/types.h>
34 #include <linux/ioport.h>
35 #include <linux/mm.h>
36 #include <linux/slab.h>
37 #include <linux/pci.h> /* struct pci_dev */
38 #include <linux/proc_fs.h>
39 #include <linux/seq_file.h>
40 #include <linux/scatterlist.h>
41 #include <linux/dma-map-ops.h>
42 #include <linux/of.h>
43
44 #include <asm/io.h>
45 #include <asm/vaddrs.h>
46 #include <asm/oplib.h>
47 #include <asm/prom.h>
48 #include <asm/page.h>
49 #include <asm/pgalloc.h>
50 #include <asm/dma.h>
51 #include <asm/iommu.h>
52 #include <asm/io-unit.h>
53 #include <asm/leon.h>
54
55 static void __iomem *_sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz);
56 static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
57 unsigned long size, char *name);
58 static void _sparc_free_io(struct resource *res);
59
60 static void register_proc_sparc_ioport(void);
61
62 /* This points to the next to use virtual memory for DVMA mappings */
63 static struct resource _sparc_dvma = {
64 .name = "sparc_dvma", .start = DVMA_VADDR, .end = DVMA_END - 1
65 };
66 /* This points to the start of I/O mappings, cluable from outside. */
67 /*ext*/ struct resource sparc_iomap = {
68 .name = "sparc_iomap", .start = IOBASE_VADDR, .end = IOBASE_END - 1
69 };
70
71 /*
72 * Our mini-allocator...
73 * Boy this is gross! We need it because we must map I/O for
74 * timers and interrupt controller before the kmalloc is available.
75 */
76
77 #define XNMLN 15
78 #define XNRES 10 /* SS-10 uses 8 */
79
80 struct xresource {
81 struct resource xres; /* Must be first */
82 int xflag; /* 1 == used */
83 char xname[XNMLN+1];
84 };
85
86 static struct xresource xresv[XNRES];
87
88 static struct xresource *xres_alloc(void) {
89 struct xresource *xrp;
90 int n;
91
92 xrp = xresv;
93 for (n = 0; n < XNRES; n++) {
94 if (xrp->xflag == 0) {
95 xrp->xflag = 1;
96 return xrp;
97 }
98 xrp++;
99 }
100 return NULL;
101 }
102
103 static void xres_free(struct xresource *xrp) {
104 xrp->xflag = 0;
105 }
106
107 /*
108 * These are typically used in PCI drivers
109 * which are trying to be cross-platform.
110 *
111 * Bus type is always zero on IIep.
112 */
113 void __iomem *ioremap(phys_addr_t offset, size_t size)
114 {
115 char name[14];
116
117 sprintf(name, "phys_%08x", (u32)offset);
118 return _sparc_alloc_io(0, (unsigned long)offset, size, name);
119 }
120 EXPORT_SYMBOL(ioremap);
121
122 /*
123 * Complementary to ioremap().
124 */
125 void iounmap(volatile void __iomem *virtual)
126 {
127 unsigned long vaddr = (unsigned long) virtual & PAGE_MASK;
128 struct resource *res;
129
130 /*
131 * XXX Too slow. Can have 8192 DVMA pages on sun4m in the worst case.
132 * This probably warrants some sort of hashing.
133 */
134 if ((res = lookup_resource(&sparc_iomap, vaddr)) == NULL) {
135 printk("free_io/iounmap: cannot free %lx\n", vaddr);
136 return;
137 }
138 _sparc_free_io(res);
139
140 if ((char *)res >= (char*)xresv && (char *)res < (char *)&xresv[XNRES]) {
141 xres_free((struct xresource *)res);
142 } else {
143 kfree(res);
144 }
145 }
146 EXPORT_SYMBOL(iounmap);
147
148 void __iomem *of_ioremap(struct resource *res, unsigned long offset,
149 unsigned long size, char *name)
150 {
151 return _sparc_alloc_io(res->flags & 0xF,
152 res->start + offset,
153 size, name);
154 }
155 EXPORT_SYMBOL(of_ioremap);
156
157 void of_iounmap(struct resource *res, void __iomem *base, unsigned long size)
158 {
159 iounmap(base);
160 }
161 EXPORT_SYMBOL(of_iounmap);
162
163 /*
164 * Meat of mapping
165 */
166 static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
167 unsigned long size, char *name)
168 {
169 static int printed_full;
170 struct xresource *xres;
171 struct resource *res;
172 char *tack;
173 int tlen;
174 void __iomem *va; /* P3 diag */
175
176 if (name == NULL) name = "???";
177
178 if ((xres = xres_alloc()) != NULL) {
179 tack = xres->xname;
180 res = &xres->xres;
181 } else {
182 if (!printed_full) {
183 printk("ioremap: done with statics, switching to malloc\n");
184 printed_full = 1;
185 }
186 tlen = strlen(name);
187 tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL);
188 if (tack == NULL) return NULL;
189 memset(tack, 0, sizeof(struct resource));
190 res = (struct resource *) tack;
191 tack += sizeof (struct resource);
192 }
193
194 strscpy(tack, name, XNMLN+1);
195 res->name = tack;
196
197 va = _sparc_ioremap(res, busno, phys, size);
198 /* printk("ioremap(0x%x:%08lx[0x%lx])=%p\n", busno, phys, size, va); */ /* P3 diag */
199 return va;
200 }
201
202 /*
203 */
204 static void __iomem *
205 _sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz)
206 {
207 unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK);
208
209 if (allocate_resource(&sparc_iomap, res,
210 (offset + sz + PAGE_SIZE-1) & PAGE_MASK,
211 sparc_iomap.start, sparc_iomap.end, PAGE_SIZE, NULL, NULL) != 0) {
212 /* Usually we cannot see printks in this case. */
213 prom_printf("alloc_io_res(%s): cannot occupy\n",
214 (res->name != NULL)? res->name: "???");
215 prom_halt();
216 }
217
218 pa &= PAGE_MASK;
219 srmmu_mapiorange(bus, pa, res->start, resource_size(res));
220
221 return (void __iomem *)(unsigned long)(res->start + offset);
222 }
223
224 /*
225 * Complementary to _sparc_ioremap().
226 */
227 static void _sparc_free_io(struct resource *res)
228 {
229 unsigned long plen;
230
231 plen = resource_size(res);
232 BUG_ON((plen & (PAGE_SIZE-1)) != 0);
233 srmmu_unmapiorange(res->start, plen);
234 release_resource(res);
235 }
236
237 unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len)
238 {
239 struct resource *res;
240
241 res = kzalloc(sizeof(*res), GFP_KERNEL);
242 if (!res)
243 return 0;
244 res->name = dev->of_node->full_name;
245
246 if (allocate_resource(&_sparc_dvma, res, len, _sparc_dvma.start,
247 _sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) {
248 printk("%s: cannot occupy 0x%zx", __func__, len);
249 kfree(res);
250 return 0;
251 }
252
253 return res->start;
254 }
255
256 bool sparc_dma_free_resource(void *cpu_addr, size_t size)
257 {
258 unsigned long addr = (unsigned long)cpu_addr;
259 struct resource *res;
260
261 res = lookup_resource(&_sparc_dvma, addr);
262 if (!res) {
263 printk("%s: cannot free %p\n", __func__, cpu_addr);
264 return false;
265 }
266
267 if ((addr & (PAGE_SIZE - 1)) != 0) {
268 printk("%s: unaligned va %p\n", __func__, cpu_addr);
269 return false;
270 }
271
272 size = PAGE_ALIGN(size);
273 if (resource_size(res) != size) {
274 printk("%s: region 0x%lx asked 0x%zx\n",
275 __func__, (long)resource_size(res), size);
276 return false;
277 }
278
279 release_resource(res);
280 kfree(res);
281 return true;
282 }
283
284 #ifdef CONFIG_SBUS
285
286 void sbus_set_sbus64(struct device *dev, int x)
287 {
288 printk("sbus_set_sbus64: unsupported\n");
289 }
290 EXPORT_SYMBOL(sbus_set_sbus64);
291
292 static int __init sparc_register_ioport(void)
293 {
294 register_proc_sparc_ioport();
295
296 return 0;
297 }
298
299 arch_initcall(sparc_register_ioport);
300
301 #endif /* CONFIG_SBUS */
302
303 /*
304 * IIep is write-through, not flushing on cpu to device transfer.
305 *
306 * On LEON systems without cache snooping, the entire D-CACHE must be flushed to
307 * make DMA to cacheable memory coherent.
308 */
309 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
310 enum dma_data_direction dir)
311 {
312 if (dir != DMA_TO_DEVICE &&
313 sparc_cpu_model == sparc_leon &&
314 !sparc_leon3_snooping_enabled())
315 leon_flush_dcache_all();
316 }
317
318 #ifdef CONFIG_PROC_FS
319
320 static int sparc_io_proc_show(struct seq_file *m, void *v)
321 {
322 struct resource *root = m->private, *r;
323 const char *nm;
324
325 for (r = root->child; r != NULL; r = r->sibling) {
326 if ((nm = r->name) == NULL) nm = "???";
327 seq_printf(m, "%016llx-%016llx: %s\n",
328 (unsigned long long)r->start,
329 (unsigned long long)r->end, nm);
330 }
331
332 return 0;
333 }
334 #endif /* CONFIG_PROC_FS */
335
336 static void register_proc_sparc_ioport(void)
337 {
338 #ifdef CONFIG_PROC_FS
339 proc_create_single_data("io_map", 0, NULL, sparc_io_proc_show,
340 &sparc_iomap);
341 proc_create_single_data("dvma_map", 0, NULL, sparc_io_proc_show,
342 &_sparc_dvma);
343 #endif
344 }
345
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