1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_BOOK3S_32_MMU_HASH_H_
3 #define _ASM_POWERPC_BOOK3S_32_MMU_HASH_H_
4 
5 /*
6  * 32-bit hash table MMU support
7  */
8 
9 /*
10  * BATs
11  */
12 
13 /* Block size masks */
14 #define BL_128K	0x000
15 #define BL_256K 0x001
16 #define BL_512K 0x003
17 #define BL_1M   0x007
18 #define BL_2M   0x00F
19 #define BL_4M   0x01F
20 #define BL_8M   0x03F
21 #define BL_16M  0x07F
22 #define BL_32M  0x0FF
23 #define BL_64M  0x1FF
24 #define BL_128M 0x3FF
25 #define BL_256M 0x7FF
26 
27 /* BAT Access Protection */
28 #define BPP_XX	0x00		/* No access */
29 #define BPP_RX	0x01		/* Read only */
30 #define BPP_RW	0x02		/* Read/write */
31 
32 #ifndef __ASSEMBLY__
33 /* Contort a phys_addr_t into the right format/bits for a BAT */
34 #ifdef CONFIG_PHYS_64BIT
35 #define BAT_PHYS_ADDR(x) ((u32)((x & 0x00000000fffe0000ULL) | \
36 				((x & 0x0000000e00000000ULL) >> 24) | \
37 				((x & 0x0000000100000000ULL) >> 30)))
38 #define PHYS_BAT_ADDR(x) (((u64)(x) & 0x00000000fffe0000ULL) | \
39 			  (((u64)(x) << 24) & 0x0000000e00000000ULL) | \
40 			  (((u64)(x) << 30) & 0x0000000100000000ULL))
41 #else
42 #define BAT_PHYS_ADDR(x) (x)
43 #define PHYS_BAT_ADDR(x) ((x) & 0xfffe0000)
44 #endif
45 
46 struct ppc_bat {
47 	u32 batu;
48 	u32 batl;
49 };
50 #endif /* !__ASSEMBLY__ */
51 
52 /*
53  * Hash table
54  */
55 
56 /* Values for PP (assumes Ks=0, Kp=1) */
57 #define PP_RWXX	0	/* Supervisor read/write, User none */
58 #define PP_RWRX 1	/* Supervisor read/write, User read */
59 #define PP_RWRW 2	/* Supervisor read/write, User read/write */
60 #define PP_RXRX 3	/* Supervisor read,       User read */
61 
62 /* Values for Segment Registers */
63 #define SR_NX	0x10000000	/* No Execute */
64 #define SR_KP	0x20000000	/* User key */
65 #define SR_KS	0x40000000	/* Supervisor key */
66 
67 #ifdef __ASSEMBLY__
68 
69 #include <asm/asm-offsets.h>
70 
71 .macro uus_addi sr reg1 reg2 imm
72 	.if NUM_USER_SEGMENTS > \sr
73 	addi	\reg1,\reg2,\imm
74 	.endif
75 .endm
76 
77 .macro uus_mtsr sr reg1
78 	.if NUM_USER_SEGMENTS > \sr
79 	mtsr	\sr, \reg1
80 	.endif
81 .endm
82 
83 /*
84  * This isync() shouldn't be necessary as the kernel is not excepted to run
85  * any instruction in userspace soon after the update of segments and 'rfi'
86  * instruction is used to return to userspace, but hash based cores
87  * (at least G3) seem to exhibit a random behaviour when the 'isync' is not
88  * there. 603 cores don't have this behaviour so don't do the 'isync' as it
89  * saves several CPU cycles.
90  */
91 .macro uus_isync
92 #ifdef CONFIG_PPC_BOOK3S_604
93 BEGIN_MMU_FTR_SECTION
94 	isync
95 END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
96 #endif
97 .endm
98 
99 .macro update_user_segments_by_4 tmp1 tmp2 tmp3 tmp4
100 	uus_addi	1, \tmp2, \tmp1, 0x111
101 	uus_addi	2, \tmp3, \tmp1, 0x222
102 	uus_addi	3, \tmp4, \tmp1, 0x333
103 
104 	uus_mtsr	0, \tmp1
105 	uus_mtsr	1, \tmp2
106 	uus_mtsr	2, \tmp3
107 	uus_mtsr	3, \tmp4
108 
109 	uus_addi	4, \tmp1, \tmp1, 0x444
110 	uus_addi	5, \tmp2, \tmp2, 0x444
111 	uus_addi	6, \tmp3, \tmp3, 0x444
112 	uus_addi	7, \tmp4, \tmp4, 0x444
113 
114 	uus_mtsr	4, \tmp1
115 	uus_mtsr	5, \tmp2
116 	uus_mtsr	6, \tmp3
117 	uus_mtsr	7, \tmp4
118 
119 	uus_addi	8, \tmp1, \tmp1, 0x444
120 	uus_addi	9, \tmp2, \tmp2, 0x444
121 	uus_addi	10, \tmp3, \tmp3, 0x444
122 	uus_addi	11, \tmp4, \tmp4, 0x444
123 
124 	uus_mtsr	8, \tmp1
125 	uus_mtsr	9, \tmp2
126 	uus_mtsr	10, \tmp3
127 	uus_mtsr	11, \tmp4
128 
129 	uus_addi	12, \tmp1, \tmp1, 0x444
130 	uus_addi	13, \tmp2, \tmp2, 0x444
131 	uus_addi	14, \tmp3, \tmp3, 0x444
132 	uus_addi	15, \tmp4, \tmp4, 0x444
133 
134 	uus_mtsr	12, \tmp1
135 	uus_mtsr	13, \tmp2
136 	uus_mtsr	14, \tmp3
137 	uus_mtsr	15, \tmp4
138 
139 	uus_isync
140 .endm
141 
142 #else
143 
144 /*
145  * This macro defines the mapping from contexts to VSIDs (virtual
146  * segment IDs).  We use a skew on both the context and the high 4 bits
147  * of the 32-bit virtual address (the "effective segment ID") in order
148  * to spread out the entries in the MMU hash table.  Note, if this
149  * function is changed then hash functions will have to be
150  * changed to correspond.
151  */
152 #define CTX_TO_VSID(c, id)	((((c) * (897 * 16)) + (id * 0x111)) & 0xffffff)
153 
154 /*
155  * Hardware Page Table Entry
156  * Note that the xpn and x bitfields are used only by processors that
157  * support extended addressing; otherwise, those bits are reserved.
158  */
159 struct hash_pte {
160 	unsigned long v:1;	/* Entry is valid */
161 	unsigned long vsid:24;	/* Virtual segment identifier */
162 	unsigned long h:1;	/* Hash algorithm indicator */
163 	unsigned long api:6;	/* Abbreviated page index */
164 	unsigned long rpn:20;	/* Real (physical) page number */
165 	unsigned long xpn:3;	/* Real page number bits 0-2, optional */
166 	unsigned long r:1;	/* Referenced */
167 	unsigned long c:1;	/* Changed */
168 	unsigned long w:1;	/* Write-thru cache mode */
169 	unsigned long i:1;	/* Cache inhibited */
170 	unsigned long m:1;	/* Memory coherence */
171 	unsigned long g:1;	/* Guarded */
172 	unsigned long x:1;	/* Real page number bit 3, optional */
173 	unsigned long pp:2;	/* Page protection */
174 };
175 
176 typedef struct {
177 	unsigned long id;
178 	unsigned long sr0;
179 	void __user *vdso;
180 } mm_context_t;
181 
182 #ifdef CONFIG_PPC_KUEP
183 #define INIT_MM_CONTEXT(mm) .context.sr0 = SR_NX
184 #endif
185 
186 void update_bats(void);
187 static inline void cleanup_cpu_mmu_context(void) { }
188 
189 /* patch sites */
190 extern s32 patch__hash_page_A0, patch__hash_page_A1, patch__hash_page_A2;
191 extern s32 patch__hash_page_B, patch__hash_page_C;
192 extern s32 patch__flush_hash_A0, patch__flush_hash_A1, patch__flush_hash_A2;
193 extern s32 patch__flush_hash_B;
194 
195 #include <asm/reg.h>
196 #include <asm/task_size_32.h>
197 
198 static __always_inline void update_user_segment(u32 n, u32 val)
199 {
200 	if (n << 28 < TASK_SIZE)
201 		mtsr(val + n * 0x111, n << 28);
202 }
203 
204 static __always_inline void update_user_segments(u32 val)
205 {
206 	val &= 0xf0ffffff;
207 
208 	update_user_segment(0, val);
209 	update_user_segment(1, val);
210 	update_user_segment(2, val);
211 	update_user_segment(3, val);
212 	update_user_segment(4, val);
213 	update_user_segment(5, val);
214 	update_user_segment(6, val);
215 	update_user_segment(7, val);
216 	update_user_segment(8, val);
217 	update_user_segment(9, val);
218 	update_user_segment(10, val);
219 	update_user_segment(11, val);
220 	update_user_segment(12, val);
221 	update_user_segment(13, val);
222 	update_user_segment(14, val);
223 	update_user_segment(15, val);
224 }
225 
226 #endif /* !__ASSEMBLY__ */
227 
228 /* We happily ignore the smaller BATs on 601, we don't actually use
229  * those definitions on hash32 at the moment anyway
230  */
231 #define mmu_virtual_psize	MMU_PAGE_4K
232 #define mmu_linear_psize	MMU_PAGE_256M
233 
234 #endif /* _ASM_POWERPC_BOOK3S_32_MMU_HASH_H_ */
235