aboutsummaryrefslogtreecommitdiffstats
path: root/arch/sparc/mm/io-unit.c
blob: 42c1c700c0a70b3c7ca86a13c90b22bf0e84fb5f (plain) (blame)
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
/* $Id: io-unit.c,v 1.24 2001/12/17 07:05:09 davem Exp $
 * io-unit.c:  IO-UNIT specific routines for memory management.
 *
 * Copyright (C) 1997,1998 Jakub Jelinek    (jj@sunsite.mff.cuni.cz)
 */
 
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/highmem.h>	/* pte_offset_map => kmap_atomic */
#include <linux/bitops.h>

#include <asm/scatterlist.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/sbus.h>
#include <asm/io.h>
#include <asm/io-unit.h>
#include <asm/mxcc.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/dma.h>

/* #define IOUNIT_DEBUG */
#ifdef IOUNIT_DEBUG
#define IOD(x) printk(x)
#else
#define IOD(x) do { } while (0)
#endif

#define IOPERM        (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)
#define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)

void __init
iounit_init(int sbi_node, int io_node, struct sbus_bus *sbus)
{
	iopte_t *xpt, *xptend;
	struct iounit_struct *iounit;
	struct linux_prom_registers iommu_promregs[PROMREG_MAX];
	struct resource r;

	iounit = kmalloc(sizeof(struct iounit_struct), GFP_ATOMIC);

	memset(iounit, 0, sizeof(*iounit));
	iounit->limit[0] = IOUNIT_BMAP1_START;
	iounit->limit[1] = IOUNIT_BMAP2_START;
	iounit->limit[2] = IOUNIT_BMAPM_START;
	iounit->limit[3] = IOUNIT_BMAPM_END;
	iounit->rotor[1] = IOUNIT_BMAP2_START;
	iounit->rotor[2] = IOUNIT_BMAPM_START;

	xpt = NULL;
	if(prom_getproperty(sbi_node, "reg", (void *) iommu_promregs,
			    sizeof(iommu_promregs)) != -1) {
		prom_apply_generic_ranges(io_node, 0, iommu_promregs, 3);
		memset(&r, 0, sizeof(r));
		r.flags = iommu_promregs[2].which_io;
		r.start = iommu_promregs[2].phys_addr;
		xpt = (iopte_t *) sbus_ioremap(&r, 0, PAGE_SIZE * 16, "XPT");
	}
	if(!xpt) panic("Cannot map External Page Table.");
	
	sbus->iommu = (struct iommu_struct *)iounit;
	iounit->page_table = xpt;
	
	for (xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
	     xpt < xptend;)
	     	iopte_val(*xpt++) = 0;
}

/* One has to hold iounit->lock to call this */
static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
{
	int i, j, k, npages;
	unsigned long rotor, scan, limit;
	iopte_t iopte;

        npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;

	/* A tiny bit of magic ingredience :) */
	switch (npages) {
	case 1: i = 0x0231; break;
	case 2: i = 0x0132; break;
	default: i = 0x0213; break;
	}
	
	IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
	
next:	j = (i & 15);
	rotor = iounit->rotor[j - 1];
	limit = iounit->limit[j];
	scan = rotor;
nexti:	scan = find_next_zero_bit(iounit->bmap, limit, scan);
	if (scan + npages > limit) {
		if (limit != rotor) {
			limit = rotor;
			scan = iounit->limit[j - 1];
			goto nexti;
		}
		i >>= 4;
		if (!(i & 15))
			panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
		goto next;
	}
	for (k = 1, scan++; k < npages; k++)
		if (test_bit(scan++, iounit->bmap))
			goto nexti;
	iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
	scan -= npages;
	iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
	vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
	for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
		set_bit(scan, iounit->bmap);
		iounit->page_table[scan] = iopte;
	}
	IOD(("%08lx\n", vaddr));
	return vaddr;
}

static __u32 iounit_get_scsi_one(char *vaddr, unsigned long len, struct sbus_bus *sbus)
{
	unsigned long ret, flags;
	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
	
	spin_lock_irqsave(&iounit->lock, flags);
	ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
	spin_unlock_irqrestore(&iounit->lock, flags);
	return ret;
}

static void iounit_get_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
{
	unsigned long flags;
	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;

	/* FIXME: Cache some resolved pages - often several sg entries are to the same page */
	spin_lock_irqsave(&iounit->lock, flags);
	while (sz != 0) {
		--sz;
		sg[sz].dvma_address = iounit_get_area(iounit, (unsigned long)page_address(sg[sz].page) + sg[sz].offset, sg[sz].length);
		sg[sz].dvma_length = sg[sz].length;
	}
	spin_unlock_irqrestore(&iounit->lock, flags);
}

static void iounit_release_scsi_one(__u32 vaddr, unsigned long len, struct sbus_bus *sbus)
{
	unsigned long flags;
	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
	
	spin_lock_irqsave(&iounit->lock, flags);
	len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
	vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
	IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
	for (len += vaddr; vaddr < len; vaddr++)
		clear_bit(vaddr, iounit->bmap);
	spin_unlock_irqrestore(&iounit->lock, flags);
}

static void iounit_release_scsi_sgl(struct scatterlist *sg, int sz, struct sbus_bus *sbus)
{
	unsigned long flags;
	unsigned long vaddr, len;
	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;

	spin_lock_irqsave(&iounit->lock, flags);
	while (sz != 0) {
		--sz;
		len = ((sg[sz].dvma_address & ~PAGE_MASK) + sg[sz].length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
		vaddr = (sg[sz].dvma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
		IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
		for (len += vaddr; vaddr < len; vaddr++)
			clear_bit(vaddr, iounit->bmap);
	}
	spin_unlock_irqrestore(&iounit->lock, flags);
}

#ifdef CONFIG_SBUS
static int iounit_map_dma_area(dma_addr_t *pba, unsigned long va, __u32 addr, int len)
{
	unsigned long page, end;
	pgprot_t dvma_prot;
	iopte_t *iopte;
	struct sbus_bus *sbus;

	*pba = addr;

	dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
	end = PAGE_ALIGN((addr + len));
	while(addr < end) {
		page = va;
		{
			pgd_t *pgdp;
			pmd_t *pmdp;
			pte_t *ptep;
			long i;

			pgdp = pgd_offset(&init_mm, addr);
			pmdp = pmd_offset(pgdp, addr);
			ptep = pte_offset_map(pmdp, addr);

			set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
			
			i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);

			for_each_sbus(sbus) {
				struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;

				iopte = (iopte_t *)(iounit->page_table + i);
				*iopte = MKIOPTE(__pa(page));
			}
		}
		addr += PAGE_SIZE;
		va += PAGE_SIZE;
	}
	flush_cache_all();
	flush_tlb_all();

	return 0;
}

static void iounit_unmap_dma_area(unsigned long addr, int len)
{
	/* XXX Somebody please fill this in */
}

/* XXX We do not pass sbus device here, bad. */
static struct page *iounit_translate_dvma(unsigned long addr)
{
	struct sbus_bus *sbus = sbus_root;	/* They are all the same */
	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
	int i;
	iopte_t *iopte;

	i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
	iopte = (iopte_t *)(iounit->page_table + i);
	return pfn_to_page(iopte_val(*iopte) >> (PAGE_SHIFT-4)); /* XXX sun4d guru, help */
}
#endif

static char *iounit_lockarea(char *vaddr, unsigned long len)
{
/* FIXME: Write this */
	return vaddr;
}

static void iounit_unlockarea(char *vaddr, unsigned long len)
{
/* FIXME: Write this */
}

void __init ld_mmu_iounit(void)
{
	BTFIXUPSET_CALL(mmu_lockarea, iounit_lockarea, BTFIXUPCALL_RETO0);
	BTFIXUPSET_CALL(mmu_unlockarea, iounit_unlockarea, BTFIXUPCALL_NOP);

	BTFIXUPSET_CALL(mmu_get_scsi_one, iounit_get_scsi_one, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(mmu_get_scsi_sgl, iounit_get_scsi_sgl, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(mmu_release_scsi_one, iounit_release_scsi_one, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(mmu_release_scsi_sgl, iounit_release_scsi_sgl, BTFIXUPCALL_NORM);

#ifdef CONFIG_SBUS
	BTFIXUPSET_CALL(mmu_map_dma_area, iounit_map_dma_area, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(mmu_unmap_dma_area, iounit_unmap_dma_area, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(mmu_translate_dvma, iounit_translate_dvma, BTFIXUPCALL_NORM);
#endif
}

__u32 iounit_map_dma_init(struct sbus_bus *sbus, int size)
{
	int i, j, k, npages;
	unsigned long rotor, scan, limit;
	unsigned long flags;
	__u32 ret;
	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;

        npages = (size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
	i = 0x0213;
	spin_lock_irqsave(&iounit->lock, flags);
next:	j = (i & 15);
	rotor = iounit->rotor[j - 1];
	limit = iounit->limit[j];
	scan = rotor;
nexti:	scan = find_next_zero_bit(iounit->bmap, limit, scan);
	if (scan + npages > limit) {
		if (limit != rotor) {
			limit = rotor;
			scan = iounit->limit[j - 1];
			goto nexti;
		}
		i >>= 4;
		if (!(i & 15))
			panic("iounit_map_dma_init: Couldn't find free iopte slots for %d bytes\n", size);
		goto next;
	}
	for (k = 1, scan++; k < npages; k++)
		if (test_bit(scan++, iounit->bmap))
			goto nexti;
	iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
	scan -= npages;
	ret = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT);
	for (k = 0; k < npages; k++, scan++)
		set_bit(scan, iounit->bmap);
	spin_unlock_irqrestore(&iounit->lock, flags);
	return ret;
}

__u32 iounit_map_dma_page(__u32 vaddr, void *addr, struct sbus_bus *sbus)
{
	int scan = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
	struct iounit_struct *iounit = (struct iounit_struct *)sbus->iommu;
	
	iounit->page_table[scan] = MKIOPTE(__pa(((unsigned long)addr) & PAGE_MASK));
	return vaddr + (((unsigned long)addr) & ~PAGE_MASK);
}