summaryrefslogtreecommitdiff
path: root/arch/sh64/mm/ioremap.c
blob: ff26c02511aa6eac58ed79bb284f7bb76604e2f0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * arch/sh64/mm/ioremap.c
 *
 * Copyright (C) 2000, 2001  Paolo Alberelli
 * Copyright (C) 2003, 2004  Paul Mundt
 *
 * Mostly derived from arch/sh/mm/ioremap.c which, in turn is mostly
 * derived from arch/i386/mm/ioremap.c .
 *
 *   (C) Copyright 1995 1996 Linus Torvalds
 */
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/io.h>
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
#include <linux/ioport.h>
#include <linux/bootmem.h>
#include <linux/proc_fs.h>

static void shmedia_mapioaddr(unsigned long, unsigned long);
static unsigned long shmedia_ioremap(struct resource *, u32, int);

/*
 * Generic mapping function (not visible outside):
 */

/*
 * Remap an arbitrary physical address space into the kernel virtual
 * address space. Needed when the kernel wants to access high addresses
 * directly.
 *
 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
 * have to convert them into an offset in a page-aligned mapping, but the
 * caller shouldn't need to know that small detail.
 */
void * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
{
	void * addr;
	struct vm_struct * area;
	unsigned long offset, last_addr;
	pgprot_t pgprot;

	/* Don't allow wraparound or zero size */
	last_addr = phys_addr + size - 1;
	if (!size || last_addr < phys_addr)
		return NULL;

	pgprot = __pgprot(_PAGE_PRESENT  | _PAGE_READ   |
			  _PAGE_WRITE    | _PAGE_DIRTY  |
			  _PAGE_ACCESSED | _PAGE_SHARED | flags);

	/*
	 * Mappings have to be page-aligned
	 */
	offset = phys_addr & ~PAGE_MASK;
	phys_addr &= PAGE_MASK;
	size = PAGE_ALIGN(last_addr + 1) - phys_addr;

	/*
	 * Ok, go for it..
	 */
	area = get_vm_area(size, VM_IOREMAP);
	pr_debug("Get vm_area returns %p addr %p\n",area,area->addr);
	if (!area)
		return NULL;
	area->phys_addr = phys_addr;
	addr = area->addr;
	if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
			       phys_addr, pgprot)) {
		vunmap(addr);
		return NULL;
	}
	return (void *) (offset + (char *)addr);
}

void iounmap(void *addr)
{
	struct vm_struct *area;

	vfree((void *) (PAGE_MASK & (unsigned long) addr));
	area = remove_vm_area((void *) (PAGE_MASK & (unsigned long) addr));
	if (!area) {
		printk(KERN_ERR "iounmap: bad address %p\n", addr);
		return;
	}

	kfree(area);
}

static struct resource shmedia_iomap = {
	.name	= "shmedia_iomap",
	.start	= IOBASE_VADDR + PAGE_SIZE,
	.end	= IOBASE_END - 1,
};

static void shmedia_mapioaddr(unsigned long pa, unsigned long va);
static void shmedia_unmapioaddr(unsigned long vaddr);
static unsigned long shmedia_ioremap(struct resource *res, u32 pa, int sz);

/*
 * We have the same problem as the SPARC, so lets have the same comment:
 * Our mini-allocator...
 * Boy this is gross! We need it because we must map I/O for
 * timers and interrupt controller before the kmalloc is available.
 */

#define XNMLN  15
#define XNRES  10

struct xresource {
	struct resource xres;   /* Must be first */
	int xflag;              /* 1 == used */
	char xname[XNMLN+1];
};

static struct xresource xresv[XNRES];

static struct xresource *xres_alloc(void)
{
        struct xresource *xrp;
        int n;

        xrp = xresv;
        for (n = 0; n < XNRES; n++) {
                if (xrp->xflag == 0) {
                        xrp->xflag = 1;
                        return xrp;
                }
                xrp++;
        }
        return NULL;
}

static void xres_free(struct xresource *xrp)
{
	xrp->xflag = 0;
}

static struct resource *shmedia_find_resource(struct resource *root,
					      unsigned long vaddr)
{
	struct resource *res;

	for (res = root->child; res; res = res->sibling)
		if (res->start <= vaddr && res->end >= vaddr)
			return res;

	return NULL;
}

static unsigned long shmedia_alloc_io(unsigned long phys, unsigned long size,
				      const char *name)
{
        static int printed_full = 0;
        struct xresource *xres;
        struct resource *res;
        char *tack;
        int tlen;

        if (name == NULL) name = "???";

        if ((xres = xres_alloc()) != 0) {
                tack = xres->xname;
                res = &xres->xres;
        } else {
                if (!printed_full) {
                        printk("%s: done with statics, switching to kmalloc\n",
			       __FUNCTION__);
                        printed_full = 1;
                }
                tlen = strlen(name);
                tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL);
                if (!tack)
			return -ENOMEM;
                memset(tack, 0, sizeof(struct resource));
                res = (struct resource *) tack;
                tack += sizeof (struct resource);
        }

        strncpy(tack, name, XNMLN);
        tack[XNMLN] = 0;
        res->name = tack;

        return shmedia_ioremap(res, phys, size);
}

static unsigned long shmedia_ioremap(struct resource *res, u32 pa, int sz)
{
        unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK);
	unsigned long round_sz = (offset + sz + PAGE_SIZE-1) & PAGE_MASK;
        unsigned long va;
        unsigned int psz;

        if (allocate_resource(&shmedia_iomap, res, round_sz,
			      shmedia_iomap.start, shmedia_iomap.end,
			      PAGE_SIZE, NULL, NULL) != 0) {
                panic("alloc_io_res(%s): cannot occupy\n",
                    (res->name != NULL)? res->name: "???");
        }

        va = res->start;
        pa &= PAGE_MASK;

	psz = (res->end - res->start + (PAGE_SIZE - 1)) / PAGE_SIZE;

	/* log at boot time ... */
	printk("mapioaddr: %6s  [%2d page%s]  va 0x%08lx   pa 0x%08x\n",
	       ((res->name != NULL) ? res->name : "???"),
	       psz, psz == 1 ? " " : "s", va, pa);

        for (psz = res->end - res->start + 1; psz != 0; psz -= PAGE_SIZE) {
                shmedia_mapioaddr(pa, va);
                va += PAGE_SIZE;
                pa += PAGE_SIZE;
        }

        res->start += offset;
        res->end = res->start + sz - 1;         /* not strictly necessary.. */

        return res->start;
}

static void shmedia_free_io(struct resource *res)
{
	unsigned long len = res->end - res->start + 1;

	BUG_ON((len & (PAGE_SIZE - 1)) != 0);

	while (len) {
		len -= PAGE_SIZE;
		shmedia_unmapioaddr(res->start + len);
	}

	release_resource(res);
}

static void *sh64_get_page(void)
{
	extern int after_bootmem;
	void *page;

	if (after_bootmem) {
		page = (void *)get_zeroed_page(GFP_ATOMIC);
	} else {
		page = alloc_bootmem_pages(PAGE_SIZE);
	}

	if (!page || ((unsigned long)page & ~PAGE_MASK))
		panic("sh64_get_page: Out of memory already?\n");

	return page;
}

static void shmedia_mapioaddr(unsigned long pa, unsigned long va)
{
	pgd_t *pgdp;
	pmd_t *pmdp;
	pte_t *ptep, pte;
	pgprot_t prot;
	unsigned long flags = 1; /* 1 = CB0-1 device */

	pr_debug("shmedia_mapiopage pa %08lx va %08lx\n",  pa, va);

	pgdp = pgd_offset_k(va);
	if (pgd_none(*pgdp) || !pgd_present(*pgdp)) {
		pmdp = (pmd_t *)sh64_get_page();
		set_pgd(pgdp, __pgd((unsigned long)pmdp | _KERNPG_TABLE));
	}

	pmdp = pmd_offset(pgdp, va);
	if (pmd_none(*pmdp) || !pmd_present(*pmdp) ) {
		ptep = (pte_t *)sh64_get_page();
		set_pmd(pmdp, __pmd((unsigned long)ptep + _PAGE_TABLE));
	}

	prot = __pgprot(_PAGE_PRESENT | _PAGE_READ     | _PAGE_WRITE  |
			_PAGE_DIRTY   | _PAGE_ACCESSED | _PAGE_SHARED | flags);

	pte = pfn_pte(pa >> PAGE_SHIFT, prot);
	ptep = pte_offset_kernel(pmdp, va);

	if (!pte_none(*ptep) &&
	    pte_val(*ptep) != pte_val(pte))
		pte_ERROR(*ptep);

	set_pte(ptep, pte);

	flush_tlb_kernel_range(va, PAGE_SIZE);
}

static void shmedia_unmapioaddr(unsigned long vaddr)
{
	pgd_t *pgdp;
	pmd_t *pmdp;
	pte_t *ptep;

	pgdp = pgd_offset_k(vaddr);
	pmdp = pmd_offset(pgdp, vaddr);

	if (pmd_none(*pmdp) || pmd_bad(*pmdp))
		return;

	ptep = pte_offset_kernel(pmdp, vaddr);

	if (pte_none(*ptep) || !pte_present(*ptep))
		return;

	clear_page((void *)ptep);
	pte_clear(&init_mm, vaddr, ptep);
}

unsigned long onchip_remap(unsigned long phys, unsigned long size, const char *name)
{
	if (size < PAGE_SIZE)
		size = PAGE_SIZE;

	return shmedia_alloc_io(phys, size, name);
}

void onchip_unmap(unsigned long vaddr)
{
	struct resource *res;
	unsigned int psz;

	res = shmedia_find_resource(&shmedia_iomap, vaddr);
	if (!res) {
		printk(KERN_ERR "%s: Failed to free 0x%08lx\n",
		       __FUNCTION__, vaddr);
		return;
	}

        psz = (res->end - res->start + (PAGE_SIZE - 1)) / PAGE_SIZE;

        printk(KERN_DEBUG "unmapioaddr: %6s  [%2d page%s] freed\n",
	       res->name, psz, psz == 1 ? " " : "s");

	shmedia_free_io(res);

	if ((char *)res >= (char *)xresv &&
	    (char *)res <  (char *)&xresv[XNRES]) {
		xres_free((struct xresource *)res);
	} else {
		kfree(res);
	}
}

#ifdef CONFIG_PROC_FS
static int
ioremap_proc_info(char *buf, char **start, off_t fpos, int length, int *eof,
		  void *data)
{
	char *p = buf, *e = buf + length;
	struct resource *r;
	const char *nm;

	for (r = ((struct resource *)data)->child; r != NULL; r = r->sibling) {
		if (p + 32 >= e)        /* Better than nothing */
			break;
		if ((nm = r->name) == 0) nm = "???";
		p += sprintf(p, "%08lx-%08lx: %s\n",
			     (unsigned long)r->start,
			     (unsigned long)r->end, nm);
	}

	return p-buf;
}
#endif /* CONFIG_PROC_FS */

static int __init register_proc_onchip(void)
{
#ifdef CONFIG_PROC_FS
	create_proc_read_entry("io_map",0,0, ioremap_proc_info, &shmedia_iomap);
#endif
	return 0;
}

__initcall(register_proc_onchip);