mmu.c
4.05 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
/*
* Copyright (c) 2006-2021, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2012-01-10 bernard porting to AM1808
*/
#include <rtthread.h>
#include "am33xx.h"
#include <mmu.h>
extern void rt_cpu_dcache_disable(void);
extern void rt_hw_cpu_dcache_enable(void);
extern void rt_cpu_icache_disable(void);
extern void rt_hw_cpu_icache_enable(void);
extern void rt_cpu_mmu_disable(void);
extern void rt_cpu_mmu_enable(void);
extern void rt_cpu_tlb_set(register rt_uint32_t i);
void mmu_disable_dcache()
{
rt_cpu_dcache_disable();
}
void mmu_enable_dcache()
{
rt_hw_cpu_dcache_enable();
}
void mmu_disable_icache()
{
rt_cpu_icache_disable();
}
void mmu_enable_icache()
{
rt_hw_cpu_icache_enable();
}
void mmu_disable()
{
rt_cpu_mmu_disable();
}
void mmu_enable()
{
rt_cpu_mmu_enable();
}
void mmu_setttbase(register rt_uint32_t i)
{
register rt_uint32_t value;
/* Invalidates all TLBs.Domain access is selected as
* client by configuring domain access register,
* in that case access controlled by permission value
* set by page table entry
*/
value = 0;
asm volatile ("mcr p15, 0, %0, c8, c7, 0"::"r"(value));
value = 0x55555555;
asm volatile ("mcr p15, 0, %0, c3, c0, 0"::"r"(value));
rt_cpu_tlb_set(i);
}
void mmu_set_domain(register rt_uint32_t i)
{
asm volatile ("mcr p15,0, %0, c3, c0, 0": :"r" (i));
}
void mmu_enable_alignfault()
{
register rt_uint32_t i;
/* read control register */
asm volatile ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
i |= (1 << 1);
/* write back to control register */
asm volatile ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
}
void mmu_disable_alignfault()
{
register rt_uint32_t i;
/* read control register */
asm volatile ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
i &= ~(1 << 1);
/* write back to control register */
asm volatile ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
}
void mmu_clean_invalidated_cache_index(int index)
{
asm volatile ("mcr p15, 0, %0, c7, c14, 2": :"r" (index));
}
void mmu_clean_dcache(rt_uint32_t buffer, rt_uint32_t size)
{
unsigned int ptr;
ptr = buffer & ~0x1f;
while (ptr < buffer + size)
{
asm volatile ("mcr p15, 0, %0, c7, c10, 1": :"r" (ptr));
ptr += 32;
}
}
void mmu_invalidate_dcache(rt_uint32_t buffer, rt_uint32_t size)
{
unsigned int ptr;
ptr = buffer & ~0x1f;
while (ptr < buffer + size)
{
asm volatile ("mcr p15, 0, %0, c7, c6, 1": :"r" (ptr));
ptr += 32;
}
}
void mmu_invalidate_tlb()
{
asm volatile ("mcr p15, 0, %0, c8, c7, 0": :"r" (0));
}
void mmu_invalidate_icache()
{
asm volatile ("mcr p15, 0, %0, c7, c5, 0": :"r" (0));
}
/* level1 page table */
static volatile unsigned int _page_table[4*1024] __attribute__((aligned(16*1024)));
void mmu_setmtt(rt_uint32_t vaddrStart, rt_uint32_t vaddrEnd, rt_uint32_t paddrStart, rt_uint32_t attr)
{
volatile rt_uint32_t *pTT;
volatile int i,nSec;
pTT=(rt_uint32_t *)_page_table+(vaddrStart>>20);
nSec=(vaddrEnd>>20)-(vaddrStart>>20);
for(i=0;i<=nSec;i++)
{
*pTT = attr |(((paddrStart>>20)+i)<<20);
pTT++;
}
}
/* set page table */
RT_WEAK void mmu_setmtts(void)
{
mmu_setmtt(0x00000000, 0xFFFFFFFF, 0x00000000, RW_NCNB); /* None cached for 4G memory */
mmu_setmtt(0x80200000, 0x80800000 - 1, 0x80200000, RW_CB); /* 126M cached DDR memory */
mmu_setmtt(0x80000000, 0x80200000 - 1, 0x80000000, RW_NCNB); /* 2M none-cached DDR memory */
mmu_setmtt(0x402F0000, 0x40300000 - 1, 0x402F0000, RW_CB); /* 63K OnChip memory */
}
void rt_hw_mmu_init(void)
{
/* disable I/D cache */
mmu_disable_dcache();
mmu_disable_icache();
mmu_disable();
mmu_invalidate_tlb();
mmu_setmtts();
/* set MMU table address */
mmu_setttbase((rt_uint32_t)_page_table);
/* enables MMU */
mmu_enable();
/* enable Instruction Cache */
mmu_enable_icache();
/* enable Data Cache */
mmu_enable_dcache();
}