dvma.c
4.57 KB
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
/*
* Virtual DMA allocation
*
* (C) 1999 Thomas Bogendoerfer (tsbogend@alpha.franken.de)
*
* 11/26/2000 -- disabled the existing code because it didn't work for
* me in 2.4. Replaced with a significantly more primitive version
* similar to the sun3 code. the old functionality was probably more
* desirable, but.... -- Sam Creasey (sammy@oh.verio.com)
*
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/vmalloc.h>
#include <asm/sun3x.h>
#include <asm/dvma.h>
#include <asm/io.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
/* IOMMU support */
#define IOMMU_ADDR_MASK 0x03ffe000
#define IOMMU_CACHE_INHIBIT 0x00000040
#define IOMMU_FULL_BLOCK 0x00000020
#define IOMMU_MODIFIED 0x00000010
#define IOMMU_USED 0x00000008
#define IOMMU_WRITE_PROTECT 0x00000004
#define IOMMU_DT_MASK 0x00000003
#define IOMMU_DT_INVALID 0x00000000
#define IOMMU_DT_VALID 0x00000001
#define IOMMU_DT_BAD 0x00000002
static volatile unsigned long *iommu_pte = (unsigned long *)SUN3X_IOMMU;
#define dvma_entry_paddr(index) (iommu_pte[index] & IOMMU_ADDR_MASK)
#define dvma_entry_vaddr(index,paddr) ((index << DVMA_PAGE_SHIFT) | \
(paddr & (DVMA_PAGE_SIZE-1)))
#if 0
#define dvma_entry_set(index,addr) (iommu_pte[index] = \
(addr & IOMMU_ADDR_MASK) | \
IOMMU_DT_VALID | IOMMU_CACHE_INHIBIT)
#else
#define dvma_entry_set(index,addr) (iommu_pte[index] = \
(addr & IOMMU_ADDR_MASK) | \
IOMMU_DT_VALID)
#endif
#define dvma_entry_clr(index) (iommu_pte[index] = IOMMU_DT_INVALID)
#define dvma_entry_hash(addr) ((addr >> DVMA_PAGE_SHIFT) ^ \
((addr & 0x03c00000) >> \
(DVMA_PAGE_SHIFT+4)))
#undef DEBUG
#ifdef DEBUG
/* code to print out a dvma mapping for debugging purposes */
void dvma_print (unsigned long dvma_addr)
{
unsigned long index;
index = dvma_addr >> DVMA_PAGE_SHIFT;
printk("idx %lx dvma_addr %08lx paddr %08lx\n", index, dvma_addr,
dvma_entry_paddr(index));
}
#endif
/* create a virtual mapping for a page assigned within the IOMMU
so that the cpu can reach it easily */
inline int dvma_map_cpu(unsigned long kaddr,
unsigned long vaddr, int len)
{
pgd_t *pgd;
unsigned long end;
int ret = 0;
kaddr &= PAGE_MASK;
vaddr &= PAGE_MASK;
end = PAGE_ALIGN(vaddr + len);
#ifdef DEBUG
printk("dvma: mapping kern %08lx to virt %08lx\n",
kaddr, vaddr);
#endif
pgd = pgd_offset_k(vaddr);
do {
pmd_t *pmd;
unsigned long end2;
if((pmd = pmd_alloc(&init_mm, pgd, vaddr)) == NULL) {
ret = -ENOMEM;
goto out;
}
if((end & PGDIR_MASK) > (vaddr & PGDIR_MASK))
end2 = (vaddr + (PGDIR_SIZE-1)) & PGDIR_MASK;
else
end2 = end;
do {
pte_t *pte;
unsigned long end3;
if((pte = pte_alloc_kernel(pmd, vaddr)) == NULL) {
ret = -ENOMEM;
goto out;
}
if((end2 & PMD_MASK) > (vaddr & PMD_MASK))
end3 = (vaddr + (PMD_SIZE-1)) & PMD_MASK;
else
end3 = end2;
do {
#ifdef DEBUG
printk("mapping %08lx phys to %08lx\n",
__pa(kaddr), vaddr);
#endif
set_pte(pte, pfn_pte(virt_to_pfn(kaddr),
PAGE_KERNEL));
pte++;
kaddr += PAGE_SIZE;
vaddr += PAGE_SIZE;
} while(vaddr < end3);
} while(vaddr < end2);
} while(vaddr < end);
flush_tlb_all();
out:
return ret;
}
inline int dvma_map_iommu(unsigned long kaddr, unsigned long baddr,
int len)
{
unsigned long end, index;
index = baddr >> DVMA_PAGE_SHIFT;
end = ((baddr+len) >> DVMA_PAGE_SHIFT);
if(len & ~DVMA_PAGE_MASK)
end++;
for(; index < end ; index++) {
// if(dvma_entry_use(index))
// BUG();
// printk("mapping pa %lx to ba %lx\n", __pa(kaddr), index << DVMA_PAGE_SHIFT);
dvma_entry_set(index, __pa(kaddr));
iommu_pte[index] |= IOMMU_FULL_BLOCK;
// dvma_entry_inc(index);
kaddr += DVMA_PAGE_SIZE;
}
#ifdef DEBUG
for(index = (baddr >> DVMA_PAGE_SHIFT); index < end; index++)
dvma_print(index << DVMA_PAGE_SHIFT);
#endif
return 0;
}
void dvma_unmap_iommu(unsigned long baddr, int len)
{
int index, end;
index = baddr >> DVMA_PAGE_SHIFT;
end = (DVMA_PAGE_ALIGN(baddr+len) >> DVMA_PAGE_SHIFT);
for(; index < end ; index++) {
#ifdef DEBUG
printk("freeing bus mapping %08x\n", index << DVMA_PAGE_SHIFT);
#endif
#if 0
if(!dvma_entry_use(index))
printk("dvma_unmap freeing unused entry %04x\n",
index);
else
dvma_entry_dec(index);
#endif
dvma_entry_clr(index);
}
}