xref: /nrf52832-nimble/rt-thread/libcpu/arm/am335x/mmu.c (revision 104654410c56c573564690304ae786df310c91fc)
1 /*
2  * Copyright (c) 2006-2018, RT-Thread Development Team
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  *
6  * Change Logs:
7  * Date           Author       Notes
8  * 2012-01-10     bernard      porting to AM1808
9  */
10 
11 #include <rtthread.h>
12 #include "am33xx.h"
13 #include <mmu.h>
14 
15 extern void rt_cpu_dcache_disable(void);
16 extern void rt_hw_cpu_dcache_enable(void);
17 extern void rt_cpu_icache_disable(void);
18 extern void rt_hw_cpu_icache_enable(void);
19 extern void rt_cpu_mmu_disable(void);
20 extern void rt_cpu_mmu_enable(void);
21 extern void rt_cpu_tlb_set(register rt_uint32_t i);
22 
mmu_disable_dcache()23 void mmu_disable_dcache()
24 {
25 	rt_cpu_dcache_disable();
26 }
27 
mmu_enable_dcache()28 void mmu_enable_dcache()
29 {
30 	rt_hw_cpu_dcache_enable();
31 }
32 
mmu_disable_icache()33 void mmu_disable_icache()
34 {
35 	rt_cpu_icache_disable();
36 }
37 
mmu_enable_icache()38 void mmu_enable_icache()
39 {
40 	rt_hw_cpu_icache_enable();
41 }
42 
mmu_disable()43 void mmu_disable()
44 {
45 	rt_cpu_mmu_disable();
46 }
47 
mmu_enable()48 void mmu_enable()
49 {
50 	rt_cpu_mmu_enable();
51 }
52 
mmu_setttbase(register rt_uint32_t i)53 void mmu_setttbase(register rt_uint32_t i)
54 {
55 	register rt_uint32_t value;
56 
57    /* Invalidates all TLBs.Domain access is selected as
58     * client by configuring domain access register,
59     * in that case access controlled by permission value
60     * set by page table entry
61     */
62 	value = 0;
63 	asm volatile ("mcr p15, 0, %0, c8, c7, 0"::"r"(value));
64 
65 	value = 0x55555555;
66 	asm volatile ("mcr p15, 0, %0, c3, c0, 0"::"r"(value));
67 
68 	rt_cpu_tlb_set(i);
69 }
70 
mmu_set_domain(register rt_uint32_t i)71 void mmu_set_domain(register rt_uint32_t i)
72 {
73 	asm volatile ("mcr p15,0, %0, c3, c0,  0": :"r" (i));
74 }
75 
mmu_enable_alignfault()76 void mmu_enable_alignfault()
77 {
78 	register rt_uint32_t i;
79 
80 	/* read control register */
81 	asm volatile ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
82 
83 	i |= (1 << 1);
84 
85 	/* write back to control register */
86 	asm volatile ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
87 }
88 
mmu_disable_alignfault()89 void mmu_disable_alignfault()
90 {
91 	register rt_uint32_t i;
92 
93 	/* read control register */
94 	asm volatile ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
95 
96 	i &= ~(1 << 1);
97 
98 	/* write back to control register */
99 	asm volatile ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
100 }
101 
mmu_clean_invalidated_cache_index(int index)102 void mmu_clean_invalidated_cache_index(int index)
103 {
104 	asm volatile ("mcr p15, 0, %0, c7, c14, 2": :"r" (index));
105 }
106 
mmu_clean_dcache(rt_uint32_t buffer,rt_uint32_t size)107 void mmu_clean_dcache(rt_uint32_t buffer, rt_uint32_t size)
108 {
109 	unsigned int ptr;
110 
111 	ptr = buffer & ~0x1f;
112 
113 	while (ptr < buffer + size)
114 	{
115 		asm volatile ("mcr p15, 0, %0, c7, c10, 1": :"r" (ptr));
116 		ptr += 32;
117 	}
118 }
119 
mmu_invalidate_dcache(rt_uint32_t buffer,rt_uint32_t size)120 void mmu_invalidate_dcache(rt_uint32_t buffer, rt_uint32_t size)
121 {
122 	unsigned int ptr;
123 
124 	ptr = buffer & ~0x1f;
125 
126 	while (ptr < buffer + size)
127 	{
128 		asm volatile ("mcr p15, 0, %0, c7, c6, 1": :"r" (ptr));
129 		ptr += 32;
130 	}
131 }
132 
mmu_invalidate_tlb()133 void mmu_invalidate_tlb()
134 {
135 	asm volatile ("mcr p15, 0, %0, c8, c7, 0": :"r" (0));
136 }
137 
mmu_invalidate_icache()138 void mmu_invalidate_icache()
139 {
140 	asm volatile ("mcr p15, 0, %0, c7, c5, 0": :"r" (0));
141 }
142 
143 /* level1 page table */
144 static volatile unsigned int _page_table[4*1024] __attribute__((aligned(16*1024)));
mmu_setmtt(rt_uint32_t vaddrStart,rt_uint32_t vaddrEnd,rt_uint32_t paddrStart,rt_uint32_t attr)145 void mmu_setmtt(rt_uint32_t vaddrStart, rt_uint32_t vaddrEnd, rt_uint32_t paddrStart, rt_uint32_t attr)
146 {
147     volatile rt_uint32_t *pTT;
148     volatile int i,nSec;
149     pTT=(rt_uint32_t *)_page_table+(vaddrStart>>20);
150     nSec=(vaddrEnd>>20)-(vaddrStart>>20);
151     for(i=0;i<=nSec;i++)
152     {
153 		*pTT = attr |(((paddrStart>>20)+i)<<20);
154 		pTT++;
155     }
156 }
157 
158 /* set page table */
mmu_setmtts(void)159 RT_WEAK void mmu_setmtts(void)
160 {
161     mmu_setmtt(0x00000000, 0xFFFFFFFF,     0x00000000, RW_NCNB);  /* None cached for 4G memory   */
162     mmu_setmtt(0x80200000, 0x80800000 - 1, 0x80200000, RW_CB);    /* 126M cached DDR memory      */
163     mmu_setmtt(0x80000000, 0x80200000 - 1, 0x80000000, RW_NCNB);  /* 2M none-cached DDR memory   */
164     mmu_setmtt(0x402F0000, 0x40300000 - 1, 0x402F0000, RW_CB);    /* 63K OnChip memory 			 */
165 }
166 
rt_hw_mmu_init(void)167 void rt_hw_mmu_init(void)
168 {
169 	/* disable I/D cache */
170 	mmu_disable_dcache();
171 	mmu_disable_icache();
172 	mmu_disable();
173 	mmu_invalidate_tlb();
174 
175     mmu_setmtts();
176 
177 	/* set MMU table address */
178 	mmu_setttbase((rt_uint32_t)_page_table);
179 
180     /* enables MMU */
181     mmu_enable();
182 
183     /* enable Instruction Cache */
184     mmu_enable_icache();
185 
186     /* enable Data Cache */
187     mmu_enable_dcache();
188 }
189 
190