1 #ifndef _ASM_POWERPC_MMU_HASH64_H_
2 #define _ASM_POWERPC_MMU_HASH64_H_
4 * PowerPC64 memory management structures
6 * Dave Engebretsen & Mike Corrigan <{engebret|mikejc}@us.ibm.com>
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
15 #include <asm/asm-compat.h>
22 #define STE_ESID_V 0x80
23 #define STE_ESID_KS 0x20
24 #define STE_ESID_KP 0x10
25 #define STE_ESID_N 0x08
27 #define STE_VSID_SHIFT 12
29 /* Location of cpu0's segment table */
30 #define STAB0_PAGE 0x6
31 #define STAB0_OFFSET (STAB0_PAGE << 12)
32 #define STAB0_PHYS_ADDR (STAB0_OFFSET + PHYSICAL_START)
35 extern char initial_stab
[];
36 #endif /* ! __ASSEMBLY */
42 #define SLB_NUM_BOLTED 3
43 #define SLB_CACHE_ENTRIES 8
44 #define SLB_MIN_SIZE 32
46 /* Bits in the SLB ESID word */
47 #define SLB_ESID_V ASM_CONST(0x0000000008000000) /* valid */
49 /* Bits in the SLB VSID word */
50 #define SLB_VSID_SHIFT 12
51 #define SLB_VSID_SHIFT_1T 24
52 #define SLB_VSID_SSIZE_SHIFT 62
53 #define SLB_VSID_B ASM_CONST(0xc000000000000000)
54 #define SLB_VSID_B_256M ASM_CONST(0x0000000000000000)
55 #define SLB_VSID_B_1T ASM_CONST(0x4000000000000000)
56 #define SLB_VSID_KS ASM_CONST(0x0000000000000800)
57 #define SLB_VSID_KP ASM_CONST(0x0000000000000400)
58 #define SLB_VSID_N ASM_CONST(0x0000000000000200) /* no-execute */
59 #define SLB_VSID_L ASM_CONST(0x0000000000000100)
60 #define SLB_VSID_C ASM_CONST(0x0000000000000080) /* class */
61 #define SLB_VSID_LP ASM_CONST(0x0000000000000030)
62 #define SLB_VSID_LP_00 ASM_CONST(0x0000000000000000)
63 #define SLB_VSID_LP_01 ASM_CONST(0x0000000000000010)
64 #define SLB_VSID_LP_10 ASM_CONST(0x0000000000000020)
65 #define SLB_VSID_LP_11 ASM_CONST(0x0000000000000030)
66 #define SLB_VSID_LLP (SLB_VSID_L|SLB_VSID_LP)
68 #define SLB_VSID_KERNEL (SLB_VSID_KP)
69 #define SLB_VSID_USER (SLB_VSID_KP|SLB_VSID_KS|SLB_VSID_C)
71 #define SLBIE_C (0x08000000)
72 #define SLBIE_SSIZE_SHIFT 25
78 #define HPTES_PER_GROUP 8
80 #define HPTE_V_SSIZE_SHIFT 62
81 #define HPTE_V_AVPN_SHIFT 7
82 #define HPTE_V_AVPN ASM_CONST(0x3fffffffffffff80)
83 #define HPTE_V_AVPN_VAL(x) (((x) & HPTE_V_AVPN) >> HPTE_V_AVPN_SHIFT)
84 #define HPTE_V_COMPARE(x,y) (!(((x) ^ (y)) & 0xffffffffffffff80UL))
85 #define HPTE_V_BOLTED ASM_CONST(0x0000000000000010)
86 #define HPTE_V_LOCK ASM_CONST(0x0000000000000008)
87 #define HPTE_V_LARGE ASM_CONST(0x0000000000000004)
88 #define HPTE_V_SECONDARY ASM_CONST(0x0000000000000002)
89 #define HPTE_V_VALID ASM_CONST(0x0000000000000001)
91 #define HPTE_R_PP0 ASM_CONST(0x8000000000000000)
92 #define HPTE_R_TS ASM_CONST(0x4000000000000000)
93 #define HPTE_R_RPN_SHIFT 12
94 #define HPTE_R_RPN ASM_CONST(0x3ffffffffffff000)
95 #define HPTE_R_FLAGS ASM_CONST(0x00000000000003ff)
96 #define HPTE_R_PP ASM_CONST(0x0000000000000003)
97 #define HPTE_R_N ASM_CONST(0x0000000000000004)
98 #define HPTE_R_C ASM_CONST(0x0000000000000080)
99 #define HPTE_R_R ASM_CONST(0x0000000000000100)
101 #define HPTE_V_1TB_SEG ASM_CONST(0x4000000000000000)
102 #define HPTE_V_VRMA_MASK ASM_CONST(0x4001ffffff000000)
104 /* Values for PP (assumes Ks=0, Kp=1) */
105 /* pp0 will always be 0 for linux */
106 #define PP_RWXX 0 /* Supervisor read/write, User none */
107 #define PP_RWRX 1 /* Supervisor read/write, User read */
108 #define PP_RWRW 2 /* Supervisor read/write, User read/write */
109 #define PP_RXRX 3 /* Supervisor read, User read */
118 extern struct hash_pte
*htab_address
;
119 extern unsigned long htab_size_bytes
;
120 extern unsigned long htab_hash_mask
;
123 * Page size definition
125 * shift : is the "PAGE_SHIFT" value for that page size
126 * sllp : is a bit mask with the value of SLB L || LP to be or'ed
127 * directly to a slbmte "vsid" value
128 * penc : is the HPTE encoding mask for the "LP" field:
133 unsigned int shift
; /* number of bits */
134 unsigned int penc
; /* HPTE encoding */
135 unsigned int tlbiel
; /* tlbiel supported for that page size */
136 unsigned long avpnm
; /* bits to mask out in AVPN in the HPTE */
137 unsigned long sllp
; /* SLB L||LP (exact mask to use in slbmte) */
140 #endif /* __ASSEMBLY__ */
144 * These are the values used by hardware in the B field of
145 * SLB entries and the first dword of MMU hashtable entries.
146 * The B field is 2 bits; the values 2 and 3 are unused and reserved.
148 #define MMU_SEGSIZE_256M 0
149 #define MMU_SEGSIZE_1T 1
155 * The current system page and segment sizes
157 extern struct mmu_psize_def mmu_psize_defs
[MMU_PAGE_COUNT
];
158 extern int mmu_linear_psize
;
159 extern int mmu_virtual_psize
;
160 extern int mmu_vmalloc_psize
;
161 extern int mmu_vmemmap_psize
;
162 extern int mmu_io_psize
;
163 extern int mmu_kernel_ssize
;
164 extern int mmu_highuser_ssize
;
165 extern u16 mmu_slb_size
;
166 extern unsigned long tce_alloc_start
, tce_alloc_end
;
169 * If the processor supports 64k normal pages but not 64k cache
170 * inhibited pages, we have to be prepared to switch processes
171 * to use 4k pages when they create cache-inhibited mappings.
172 * If this is the case, mmu_ci_restrictions will be set to 1.
174 extern int mmu_ci_restrictions
;
177 * This function sets the AVPN and L fields of the HPTE appropriately
180 static inline unsigned long hpte_encode_v(unsigned long va
, int psize
,
184 v
= (va
>> 23) & ~(mmu_psize_defs
[psize
].avpnm
);
185 v
<<= HPTE_V_AVPN_SHIFT
;
186 if (psize
!= MMU_PAGE_4K
)
188 v
|= ((unsigned long) ssize
) << HPTE_V_SSIZE_SHIFT
;
193 * This function sets the ARPN, and LP fields of the HPTE appropriately
194 * for the page size. We assume the pa is already "clean" that is properly
195 * aligned for the requested page size
197 static inline unsigned long hpte_encode_r(unsigned long pa
, int psize
)
201 /* A 4K page needs no special encoding */
202 if (psize
== MMU_PAGE_4K
)
203 return pa
& HPTE_R_RPN
;
205 unsigned int penc
= mmu_psize_defs
[psize
].penc
;
206 unsigned int shift
= mmu_psize_defs
[psize
].shift
;
207 return (pa
& ~((1ul << shift
) - 1)) | (penc
<< 12);
213 * Build a VA given VSID, EA and segment size
215 static inline unsigned long hpt_va(unsigned long ea
, unsigned long vsid
,
218 if (ssize
== MMU_SEGSIZE_256M
)
219 return (vsid
<< 28) | (ea
& 0xfffffffUL
);
220 return (vsid
<< 40) | (ea
& 0xffffffffffUL
);
224 * This hashes a virtual address
227 static inline unsigned long hpt_hash(unsigned long va
, unsigned int shift
,
230 unsigned long hash
, vsid
;
232 if (ssize
== MMU_SEGSIZE_256M
) {
233 hash
= (va
>> 28) ^ ((va
& 0x0fffffffUL
) >> shift
);
236 hash
= vsid
^ (vsid
<< 25) ^ ((va
& 0xffffffffffUL
) >> shift
);
238 return hash
& 0x7fffffffffUL
;
241 extern int __hash_page_4K(unsigned long ea
, unsigned long access
,
242 unsigned long vsid
, pte_t
*ptep
, unsigned long trap
,
243 unsigned int local
, int ssize
, int subpage_prot
);
244 extern int __hash_page_64K(unsigned long ea
, unsigned long access
,
245 unsigned long vsid
, pte_t
*ptep
, unsigned long trap
,
246 unsigned int local
, int ssize
);
248 unsigned int hash_page_do_lazy_icache(unsigned int pp
, pte_t pte
, int trap
);
249 extern int hash_page(unsigned long ea
, unsigned long access
, unsigned long trap
);
250 int __hash_page_huge(unsigned long ea
, unsigned long access
, unsigned long vsid
,
251 pte_t
*ptep
, unsigned long trap
, int local
, int ssize
,
252 unsigned int shift
, unsigned int mmu_psize
);
254 extern int htab_bolt_mapping(unsigned long vstart
, unsigned long vend
,
255 unsigned long pstart
, unsigned long prot
,
256 int psize
, int ssize
);
257 extern void add_gpage(unsigned long addr
, unsigned long page_size
,
258 unsigned long number_of_pages
);
259 extern void demote_segment_4k(struct mm_struct
*mm
, unsigned long addr
);
261 extern void hpte_init_native(void);
262 extern void hpte_init_lpar(void);
263 extern void hpte_init_iSeries(void);
264 extern void hpte_init_beat(void);
265 extern void hpte_init_beat_v3(void);
267 extern void stabs_alloc(void);
268 extern void slb_initialize(void);
269 extern void slb_flush_and_rebolt(void);
270 extern void stab_initialize(unsigned long stab
);
272 extern void slb_vmalloc_update(void);
273 extern void slb_set_size(u16 size
);
274 #endif /* __ASSEMBLY__ */
279 * We first generate a 36-bit "proto-VSID". For kernel addresses this
280 * is equal to the ESID, for user addresses it is:
281 * (context << 15) | (esid & 0x7fff)
283 * The two forms are distinguishable because the top bit is 0 for user
284 * addresses, whereas the top two bits are 1 for kernel addresses.
285 * Proto-VSIDs with the top two bits equal to 0b10 are reserved for
288 * The proto-VSIDs are then scrambled into real VSIDs with the
289 * multiplicative hash:
291 * VSID = (proto-VSID * VSID_MULTIPLIER) % VSID_MODULUS
292 * where VSID_MULTIPLIER = 268435399 = 0xFFFFFC7
293 * VSID_MODULUS = 2^36-1 = 0xFFFFFFFFF
295 * This scramble is only well defined for proto-VSIDs below
296 * 0xFFFFFFFFF, so both proto-VSID and actual VSID 0xFFFFFFFFF are
297 * reserved. VSID_MULTIPLIER is prime, so in particular it is
298 * co-prime to VSID_MODULUS, making this a 1:1 scrambling function.
299 * Because the modulus is 2^n-1 we can compute it efficiently without
300 * a divide or extra multiply (see below).
302 * This scheme has several advantages over older methods:
304 * - We have VSIDs allocated for every kernel address
305 * (i.e. everything above 0xC000000000000000), except the very top
306 * segment, which simplifies several things.
308 * - We allow for 15 significant bits of ESID and 20 bits of
309 * context for user addresses. i.e. 8T (43 bits) of address space for
310 * up to 1M contexts (although the page table structure and context
311 * allocation will need changes to take advantage of this).
313 * - The scramble function gives robust scattering in the hash
314 * table (at least based on some initial results). The previous
315 * method was more susceptible to pathological cases giving excessive
319 * WARNING - If you change these you must make sure the asm
320 * implementations in slb_allocate (slb_low.S), do_stab_bolted
321 * (head.S) and ASM_VSID_SCRAMBLE (below) are changed accordingly.
323 * You'll also need to change the precomputed VSID values in head.S
324 * which are used by the iSeries firmware.
327 #define VSID_MULTIPLIER_256M ASM_CONST(200730139) /* 28-bit prime */
328 #define VSID_BITS_256M 36
329 #define VSID_MODULUS_256M ((1UL<<VSID_BITS_256M)-1)
331 #define VSID_MULTIPLIER_1T ASM_CONST(12538073) /* 24-bit prime */
332 #define VSID_BITS_1T 24
333 #define VSID_MODULUS_1T ((1UL<<VSID_BITS_1T)-1)
335 #define CONTEXT_BITS 19
336 #define USER_ESID_BITS 16
337 #define USER_ESID_BITS_1T 4
339 #define USER_VSID_RANGE (1UL << (USER_ESID_BITS + SID_SHIFT))
342 * This macro generates asm code to compute the VSID scramble
343 * function. Used in slb_allocate() and do_stab_bolted. The function
344 * computed is: (protovsid*VSID_MULTIPLIER) % VSID_MODULUS
346 * rt = register continaing the proto-VSID and into which the
347 * VSID will be stored
348 * rx = scratch register (clobbered)
350 * - rt and rx must be different registers
351 * - The answer will end up in the low VSID_BITS bits of rt. The higher
352 * bits may contain other garbage, so you may need to mask the
355 #define ASM_VSID_SCRAMBLE(rt, rx, size) \
356 lis rx,VSID_MULTIPLIER_##size@h; \
357 ori rx,rx,VSID_MULTIPLIER_##size@l; \
358 mulld rt,rt,rx; /* rt = rt * MULTIPLIER */ \
360 srdi rx,rt,VSID_BITS_##size; \
361 clrldi rt,rt,(64-VSID_BITS_##size); \
362 add rt,rt,rx; /* add high and low bits */ \
363 /* Now, r3 == VSID (mod 2^36-1), and lies between 0 and \
364 * 2^36-1+2^28-1. That in particular means that if r3 >= \
365 * 2^36-1, then r3+1 has the 2^36 bit set. So, if r3+1 has \
366 * the bit clear, r3 already has the answer we want, if it \
367 * doesn't, the answer is the low 36 bits of r3+1. So in all \
368 * cases the answer is the low 36 bits of (r3 + ((r3+1) >> 36))*/\
370 srdi rx,rx,VSID_BITS_##size; /* extract 2^VSID_BITS bit */ \
376 #ifdef CONFIG_PPC_SUBPAGE_PROT
378 * For the sub-page protection option, we extend the PGD with one of
379 * these. Basically we have a 3-level tree, with the top level being
380 * the protptrs array. To optimize speed and memory consumption when
381 * only addresses < 4GB are being protected, pointers to the first
382 * four pages of sub-page protection words are stored in the low_prot
384 * Each page of sub-page protection words protects 1GB (4 bytes
385 * protects 64k). For the 3-level tree, each page of pointers then
388 struct subpage_prot_table
{
389 unsigned long maxaddr
; /* only addresses < this are protected */
390 unsigned int **protptrs
[2];
391 unsigned int *low_prot
[4];
394 #define SBP_L1_BITS (PAGE_SHIFT - 2)
395 #define SBP_L2_BITS (PAGE_SHIFT - 3)
396 #define SBP_L1_COUNT (1 << SBP_L1_BITS)
397 #define SBP_L2_COUNT (1 << SBP_L2_BITS)
398 #define SBP_L2_SHIFT (PAGE_SHIFT + SBP_L1_BITS)
399 #define SBP_L3_SHIFT (SBP_L2_SHIFT + SBP_L2_BITS)
401 extern void subpage_prot_free(struct mm_struct
*mm
);
402 extern void subpage_prot_init_new_context(struct mm_struct
*mm
);
404 static inline void subpage_prot_free(struct mm_struct
*mm
) {}
405 static inline void subpage_prot_init_new_context(struct mm_struct
*mm
) { }
406 #endif /* CONFIG_PPC_SUBPAGE_PROT */
408 typedef unsigned long mm_context_id_t
;
412 u16 user_psize
; /* page size index */
414 #ifdef CONFIG_PPC_MM_SLICES
415 u64 low_slices_psize
; /* SLB page size encodings */
416 u64 high_slices_psize
; /* 4 bits per slice for now */
418 u16 sllp
; /* SLB page size encoding */
420 unsigned long vdso_base
;
421 #ifdef CONFIG_PPC_SUBPAGE_PROT
422 struct subpage_prot_table spt
;
423 #endif /* CONFIG_PPC_SUBPAGE_PROT */
429 * The code below is equivalent to this function for arguments
430 * < 2^VSID_BITS, which is all this should ever be called
431 * with. However gcc is not clever enough to compute the
432 * modulus (2^n-1) without a second multiply.
434 #define vsid_scrample(protovsid, size) \
435 ((((protovsid) * VSID_MULTIPLIER_##size) % VSID_MODULUS_##size))
438 #define vsid_scramble(protovsid, size) \
441 x = (protovsid) * VSID_MULTIPLIER_##size; \
442 x = (x >> VSID_BITS_##size) + (x & VSID_MODULUS_##size); \
443 (x + ((x+1) >> VSID_BITS_##size)) & VSID_MODULUS_##size; \
447 /* This is only valid for addresses >= PAGE_OFFSET */
448 static inline unsigned long get_kernel_vsid(unsigned long ea
, int ssize
)
450 if (ssize
== MMU_SEGSIZE_256M
)
451 return vsid_scramble(ea
>> SID_SHIFT
, 256M
);
452 return vsid_scramble(ea
>> SID_SHIFT_1T
, 1T
);
455 /* Returns the segment size indicator for a user address */
456 static inline int user_segment_size(unsigned long addr
)
458 /* Use 1T segments if possible for addresses >= 1T */
459 if (addr
>= (1UL << SID_SHIFT_1T
))
460 return mmu_highuser_ssize
;
461 return MMU_SEGSIZE_256M
;
464 /* This is only valid for user addresses (which are below 2^44) */
465 static inline unsigned long get_vsid(unsigned long context
, unsigned long ea
,
468 if (ssize
== MMU_SEGSIZE_256M
)
469 return vsid_scramble((context
<< USER_ESID_BITS
)
470 | (ea
>> SID_SHIFT
), 256M
);
471 return vsid_scramble((context
<< USER_ESID_BITS_1T
)
472 | (ea
>> SID_SHIFT_1T
), 1T
);
476 * This is only used on legacy iSeries in lparmap.c,
477 * hence the 256MB segment assumption.
479 #define VSID_SCRAMBLE(pvsid) (((pvsid) * VSID_MULTIPLIER_256M) % \
481 #define KERNEL_VSID(ea) VSID_SCRAMBLE(GET_ESID(ea))
483 #endif /* __ASSEMBLY__ */
485 #endif /* _ASM_POWERPC_MMU_HASH64_H_ */