1 /*
2  * arch/xtensa/include/asm/initialize_mmu.h
3  *
4  * Initializes MMU:
5  *
6  *      For the new V3 MMU we remap the TLB from virtual == physical
7  *      to the standard Linux mapping used in earlier MMU's.
8  *
9  *      The the MMU we also support a new configuration register that
10  *      specifies how the S32C1I instruction operates with the cache
11  *      controller.
12  *
13  * This file is subject to the terms and conditions of the GNU General
14  * Public License.  See the file "COPYING" in the main directory of
15  * this archive for more details.
16  *
17  * Copyright (C) 2008 - 2012 Tensilica, Inc.
18  *
19  *   Marc Gauthier <marc@tensilica.com>
20  *   Pete Delaney <piet@tensilica.com>
21  */
22 
23 #ifndef _XTENSA_INITIALIZE_MMU_H
24 #define _XTENSA_INITIALIZE_MMU_H
25 
26 #include <asm/pgtable.h>
27 #include <asm/vectors.h>
28 
29 #if XCHAL_HAVE_PTP_MMU
30 #define CA_BYPASS	(_PAGE_CA_BYPASS | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
31 #define CA_WRITEBACK	(_PAGE_CA_WB     | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
32 #else
33 #define CA_WRITEBACK	(0x4)
34 #endif
35 
36 #ifdef __ASSEMBLY__
37 
38 #define XTENSA_HWVERSION_RC_2009_0 230000
39 
40 	.macro	initialize_mmu
41 
42 #if XCHAL_HAVE_S32C1I && (XCHAL_HW_MIN_VERSION >= XTENSA_HWVERSION_RC_2009_0)
43 /*
44  * We Have Atomic Operation Control (ATOMCTL) Register; Initialize it.
45  * For details see Documentation/xtensa/atomctl.txt
46  */
47 #if XCHAL_DCACHE_IS_COHERENT
48 	movi	a3, 0x25	/* For SMP/MX -- internal for writeback,
49 				 * RCW otherwise
50 				 */
51 #else
52 	movi	a3, 0x29	/* non-MX -- Most cores use Std Memory
53 				 * Controlers which usually can't use RCW
54 				 */
55 #endif
56 	wsr	a3, atomctl
57 #endif  /* XCHAL_HAVE_S32C1I &&
58 	 * (XCHAL_HW_MIN_VERSION >= XTENSA_HWVERSION_RC_2009_0)
59 	 */
60 
61 #if defined(CONFIG_MMU) && XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
62 /*
63  * Have MMU v3
64  */
65 
66 #if !XCHAL_HAVE_VECBASE
67 # error "MMU v3 requires reloc vectors"
68 #endif
69 
70 	movi	a1, 0
71 	_call0	1f
72 	_j	2f
73 
74 	.align	4
75 1:	movi	a2, 0x10000000
76 
77 #if CONFIG_KERNEL_LOAD_ADDRESS < 0x40000000ul
78 #define TEMP_MAPPING_VADDR 0x40000000
79 #else
80 #define TEMP_MAPPING_VADDR 0x00000000
81 #endif
82 
83 	/* Step 1: invalidate mapping at 0x40000000..0x5FFFFFFF. */
84 
85 	movi	a2, TEMP_MAPPING_VADDR | XCHAL_SPANNING_WAY
86 	idtlb	a2
87 	iitlb	a2
88 	isync
89 
90 	/* Step 2: map 0x40000000..0x47FFFFFF to paddr containing this code
91 	 * and jump to the new mapping.
92 	 */
93 
94 	srli	a3, a0, 27
95 	slli	a3, a3, 27
96 	addi	a3, a3, CA_BYPASS
97 	addi	a7, a2, 5 - XCHAL_SPANNING_WAY
98 	wdtlb	a3, a7
99 	witlb	a3, a7
100 	isync
101 
102 	slli	a4, a0, 5
103 	srli	a4, a4, 5
104 	addi	a5, a2, -XCHAL_SPANNING_WAY
105 	add	a4, a4, a5
106 	jx	a4
107 
108 	/* Step 3: unmap everything other than current area.
109 	 *	   Start at 0x60000000, wrap around, and end with 0x20000000
110 	 */
111 2:	movi	a4, 0x20000000
112 	add	a5, a2, a4
113 3:	idtlb	a5
114 	iitlb	a5
115 	add	a5, a5, a4
116 	bne	a5, a2, 3b
117 
118 	/* Step 4: Setup MMU with the requested static mappings. */
119 
120 	movi	a6, 0x01000000
121 	wsr	a6, ITLBCFG
122 	wsr	a6, DTLBCFG
123 	isync
124 
125 	movi	a5, XCHAL_KSEG_CACHED_VADDR + XCHAL_KSEG_TLB_WAY
126 	movi	a4, XCHAL_KSEG_PADDR + CA_WRITEBACK
127 	wdtlb	a4, a5
128 	witlb	a4, a5
129 
130 	movi	a5, XCHAL_KSEG_BYPASS_VADDR + XCHAL_KSEG_TLB_WAY
131 	movi	a4, XCHAL_KSEG_PADDR + CA_BYPASS
132 	wdtlb	a4, a5
133 	witlb	a4, a5
134 
135 #ifdef CONFIG_XTENSA_KSEG_512M
136 	movi	a5, XCHAL_KSEG_CACHED_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY
137 	movi	a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_WRITEBACK
138 	wdtlb	a4, a5
139 	witlb	a4, a5
140 
141 	movi	a5, XCHAL_KSEG_BYPASS_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY
142 	movi	a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_BYPASS
143 	wdtlb	a4, a5
144 	witlb	a4, a5
145 #endif
146 
147 	movi	a5, XCHAL_KIO_CACHED_VADDR + XCHAL_KIO_TLB_WAY
148 	movi	a4, XCHAL_KIO_DEFAULT_PADDR + CA_WRITEBACK
149 	wdtlb	a4, a5
150 	witlb	a4, a5
151 
152 	movi	a5, XCHAL_KIO_BYPASS_VADDR + XCHAL_KIO_TLB_WAY
153 	movi	a4, XCHAL_KIO_DEFAULT_PADDR + CA_BYPASS
154 	wdtlb	a4, a5
155 	witlb	a4, a5
156 
157 	isync
158 
159 	/* Jump to self, using final mappings. */
160 	movi	a4, 1f
161 	jx	a4
162 
163 1:
164 	/* Step 5: remove temporary mapping. */
165 	idtlb	a7
166 	iitlb	a7
167 	isync
168 
169 	movi	a0, 0
170 	wsr	a0, ptevaddr
171 	rsync
172 
173 #endif /* defined(CONFIG_MMU) && XCHAL_HAVE_PTP_MMU &&
174 	  XCHAL_HAVE_SPANNING_WAY */
175 
176 	.endm
177 
178 	.macro	initialize_cacheattr
179 
180 #if !defined(CONFIG_MMU) && (XCHAL_HAVE_TLBS || XCHAL_HAVE_MPU)
181 #if CONFIG_MEMMAP_CACHEATTR == 0x22222222 && XCHAL_HAVE_PTP_MMU
182 #error Default MEMMAP_CACHEATTR of 0x22222222 does not work with full MMU.
183 #endif
184 
185 #if XCHAL_HAVE_MPU
186 	.data
187 	.align	4
188 .Lattribute_table:
189 	.long 0x000000, 0x1fff00, 0x1ddf00, 0x1eef00
190 	.long 0x006600, 0x000000, 0x000000, 0x000000
191 	.long 0x000000, 0x000000, 0x000000, 0x000000
192 	.long 0x000000, 0x000000, 0x000000, 0x000000
193 	.previous
194 
195 	movi	a3, .Lattribute_table
196 	movi	a4, CONFIG_MEMMAP_CACHEATTR
197 	movi	a5, 1
198 	movi	a6, XCHAL_MPU_ENTRIES
199 	movi	a10, 0x20000000
200 	movi	a11, -1
201 1:
202 	sub	a5, a5, a10
203 	extui	a8, a4, 28, 4
204 	beq	a8, a11, 2f
205 	addi	a6, a6, -1
206 	mov	a11, a8
207 2:
208 	addx4	a9, a8, a3
209 	l32i	a9, a9, 0
210 	or	a9, a9, a6
211 	wptlb	a9, a5
212 	slli	a4, a4, 4
213 	bgeu	a5, a10, 1b
214 
215 #else
216 	movi	a5, XCHAL_SPANNING_WAY
217 	movi	a6, ~_PAGE_ATTRIB_MASK
218 	movi	a4, CONFIG_MEMMAP_CACHEATTR
219 	movi	a8, 0x20000000
220 1:
221 	rdtlb1	a3, a5
222 	xor	a3, a3, a4
223 	and	a3, a3, a6
224 	xor	a3, a3, a4
225 	wdtlb	a3, a5
226 	ritlb1	a3, a5
227 	xor	a3, a3, a4
228 	and	a3, a3, a6
229 	xor	a3, a3, a4
230 	witlb	a3, a5
231 
232 	add	a5, a5, a8
233 	srli	a4, a4, 4
234 	bgeu	a5, a8, 1b
235 
236 	isync
237 #endif
238 #endif
239 
240 	.endm
241 
242 #endif /*__ASSEMBLY__*/
243 
244 #endif /* _XTENSA_INITIALIZE_MMU_H */
245