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
|
// SPDX-License-Identifier: GPL-2.0
/*
* 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/bitops.h>
#include <linux/dma-map-ops.h>
#include <linux/of.h>
#include <linux/of_device.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>
#include <asm/oplib.h>
#include "mm_32.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)
static const struct dma_map_ops iounit_dma_ops;
static void __init iounit_iommu_init(struct platform_device *op)
{
struct iounit_struct *iounit;
iopte_t __iomem *xpt;
iopte_t __iomem *xptend;
iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC);
if (!iounit) {
prom_printf("SUN4D: Cannot alloc iounit, halting.\n");
prom_halt();
}
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 = of_ioremap(&op->resource[2], 0, PAGE_SIZE * 16, "XPT");
if (!xpt) {
prom_printf("SUN4D: Cannot map External Page Table.");
prom_halt();
}
op->dev.archdata.iommu = iounit;
iounit->page_table = xpt;
spin_lock_init(&iounit->lock);
xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
for (; xpt < xptend; xpt++)
sbus_writel(0, xpt);
op->dev.dma_ops = &iounit_dma_ops;
}
static int __init iounit_init(void)
{
extern void sun4d_init_sbi_irq(void);
struct device_node *dp;
for_each_node_by_name(dp, "sbi") {
struct platform_device *op = of_find_device_by_node(dp);
iounit_iommu_init(op);
of_propagate_archdata(op);
}
sun4d_init_sbi_irq();
return 0;
}
subsys_initcall(iounit_init);
/* 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);
sbus_writel(iopte_val(iopte), &iounit->page_table[scan]);
}
IOD(("%08lx\n", vaddr));
return vaddr;
}
static dma_addr_t iounit_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t len, enum dma_data_direction dir,
unsigned long attrs)
{
void *vaddr = page_address(page) + offset;
struct iounit_struct *iounit = dev->archdata.iommu;
unsigned long ret, flags;
/* XXX So what is maxphys for us and how do drivers know it? */
if (!len || len > 256 * 1024)
return DMA_MAPPING_ERROR;
spin_lock_irqsave(&iounit->lock, flags);
ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
spin_unlock_irqrestore(&iounit->lock, flags);
return ret;
}
static int iounit_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
enum dma_data_direction dir, unsigned long attrs)
{
struct iounit_struct *iounit = dev->archdata.iommu;
struct scatterlist *sg;
unsigned long flags;
int i;
/* FIXME: Cache some resolved pages - often several sg entries are to the same page */
spin_lock_irqsave(&iounit->lock, flags);
for_each_sg(sgl, sg, nents, i) {
sg->dma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length);
sg->dma_length = sg->length;
}
spin_unlock_irqrestore(&iounit->lock, flags);
return nents;
}
static void iounit_unmap_page(struct device *dev, dma_addr_t vaddr, size_t len,
enum dma_data_direction dir, unsigned long attrs)
{
struct iounit_struct *iounit = dev->archdata.iommu;
unsigned long flags;
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_unmap_sg(struct device *dev, struct scatterlist *sgl,
int nents, enum dma_data_direction dir, unsigned long attrs)
{
struct iounit_struct *iounit = dev->archdata.iommu;
unsigned long flags, vaddr, len;
struct scatterlist *sg;
int i;
spin_lock_irqsave(&iounit->lock, flags);
for_each_sg(sgl, sg, nents, i) {
len = ((sg->dma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
vaddr = (sg->dma_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 void *iounit_alloc(struct device *dev, size_t len,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
|