1 #ifndef _ASM_POWERPC_BOOK3S_64_MMU_HASH_H_
2 #define _ASM_POWERPC_BOOK3S_64_MMU_HASH_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>
20 * This is necessary to get the definition of PGTABLE_RANGE which we
21 * need for various slices related matters. Note that this isn't the
22 * complete pgtable.h but only a portion of it.
24 #include <asm/book3s/64/pgtable.h>
26 #include <asm/processor.h>
27 #include <asm/cpu_has_feature.h>
33 #define SLB_NUM_BOLTED 3
34 #define SLB_CACHE_ENTRIES 8
35 #define SLB_MIN_SIZE 32
37 /* Bits in the SLB ESID word */
38 #define SLB_ESID_V ASM_CONST(0x0000000008000000) /* valid */
40 /* Bits in the SLB VSID word */
41 #define SLB_VSID_SHIFT 12
42 #define SLB_VSID_SHIFT_1T 24
43 #define SLB_VSID_SSIZE_SHIFT 62
44 #define SLB_VSID_B ASM_CONST(0xc000000000000000)
45 #define SLB_VSID_B_256M ASM_CONST(0x0000000000000000)
46 #define SLB_VSID_B_1T ASM_CONST(0x4000000000000000)
47 #define SLB_VSID_KS ASM_CONST(0x0000000000000800)
48 #define SLB_VSID_KP ASM_CONST(0x0000000000000400)
49 #define SLB_VSID_N ASM_CONST(0x0000000000000200) /* no-execute */
50 #define SLB_VSID_L ASM_CONST(0x0000000000000100)
51 #define SLB_VSID_C ASM_CONST(0x0000000000000080) /* class */
52 #define SLB_VSID_LP ASM_CONST(0x0000000000000030)
53 #define SLB_VSID_LP_00 ASM_CONST(0x0000000000000000)
54 #define SLB_VSID_LP_01 ASM_CONST(0x0000000000000010)
55 #define SLB_VSID_LP_10 ASM_CONST(0x0000000000000020)
56 #define SLB_VSID_LP_11 ASM_CONST(0x0000000000000030)
57 #define SLB_VSID_LLP (SLB_VSID_L|SLB_VSID_LP)
59 #define SLB_VSID_KERNEL (SLB_VSID_KP)
60 #define SLB_VSID_USER (SLB_VSID_KP|SLB_VSID_KS|SLB_VSID_C)
62 #define SLBIE_C (0x08000000)
63 #define SLBIE_SSIZE_SHIFT 25
69 #define HPTES_PER_GROUP 8
71 #define HPTE_V_SSIZE_SHIFT 62
72 #define HPTE_V_AVPN_SHIFT 7
73 #define HPTE_V_AVPN ASM_CONST(0x3fffffffffffff80)
74 #define HPTE_V_AVPN_VAL(x) (((x) & HPTE_V_AVPN) >> HPTE_V_AVPN_SHIFT)
75 #define HPTE_V_COMPARE(x,y) (!(((x) ^ (y)) & 0xffffffffffffff80UL))
76 #define HPTE_V_BOLTED ASM_CONST(0x0000000000000010)
77 #define HPTE_V_LOCK ASM_CONST(0x0000000000000008)
78 #define HPTE_V_LARGE ASM_CONST(0x0000000000000004)
79 #define HPTE_V_SECONDARY ASM_CONST(0x0000000000000002)
80 #define HPTE_V_VALID ASM_CONST(0x0000000000000001)
83 * ISA 3.0 have a different HPTE format.
85 #define HPTE_R_3_0_SSIZE_SHIFT 58
86 #define HPTE_R_PP0 ASM_CONST(0x8000000000000000)
87 #define HPTE_R_TS ASM_CONST(0x4000000000000000)
88 #define HPTE_R_KEY_HI ASM_CONST(0x3000000000000000)
89 #define HPTE_R_RPN_SHIFT 12
90 #define HPTE_R_RPN ASM_CONST(0x0ffffffffffff000)
91 #define HPTE_R_PP ASM_CONST(0x0000000000000003)
92 #define HPTE_R_PPP ASM_CONST(0x8000000000000003)
93 #define HPTE_R_N ASM_CONST(0x0000000000000004)
94 #define HPTE_R_G ASM_CONST(0x0000000000000008)
95 #define HPTE_R_M ASM_CONST(0x0000000000000010)
96 #define HPTE_R_I ASM_CONST(0x0000000000000020)
97 #define HPTE_R_W ASM_CONST(0x0000000000000040)
98 #define HPTE_R_WIMG ASM_CONST(0x0000000000000078)
99 #define HPTE_R_C ASM_CONST(0x0000000000000080)
100 #define HPTE_R_R ASM_CONST(0x0000000000000100)
101 #define HPTE_R_KEY_LO ASM_CONST(0x0000000000000e00)
103 #define HPTE_V_1TB_SEG ASM_CONST(0x4000000000000000)
104 #define HPTE_V_VRMA_MASK ASM_CONST(0x4001ffffff000000)
106 /* Values for PP (assumes Ks=0, Kp=1) */
107 #define PP_RWXX 0 /* Supervisor read/write, User none */
108 #define PP_RWRX 1 /* Supervisor read/write, User read */
109 #define PP_RWRW 2 /* Supervisor read/write, User read/write */
110 #define PP_RXRX 3 /* Supervisor read, User read */
111 #define PP_RXXX (HPTE_R_PP0 | 2) /* Supervisor read, user none */
113 /* Fields for tlbiel instruction in architecture 2.06 */
114 #define TLBIEL_INVAL_SEL_MASK 0xc00 /* invalidation selector */
115 #define TLBIEL_INVAL_PAGE 0x000 /* invalidate a single page */
116 #define TLBIEL_INVAL_SET_LPID 0x800 /* invalidate a set for current LPID */
117 #define TLBIEL_INVAL_SET 0xc00 /* invalidate a set for all LPIDs */
118 #define TLBIEL_INVAL_SET_MASK 0xfff000 /* set number to inval. */
119 #define TLBIEL_INVAL_SET_SHIFT 12
121 #define POWER7_TLB_SETS 128 /* # sets in POWER7 TLB */
122 #define POWER8_TLB_SETS 512 /* # sets in POWER8 TLB */
123 #define POWER9_TLB_SETS_HASH 256 /* # sets in POWER9 TLB Hash mode */
124 #define POWER9_TLB_SETS_RADIX 128 /* # sets in POWER9 TLB Radix mode */
128 struct mmu_hash_ops {
129 void (*hpte_invalidate)(unsigned long slot,
131 int bpsize, int apsize,
132 int ssize, int local);
133 long (*hpte_updatepp)(unsigned long slot,
136 int bpsize, int apsize,
137 int ssize, unsigned long flags);
138 void (*hpte_updateboltedpp)(unsigned long newpp,
140 int psize, int ssize);
141 long (*hpte_insert)(unsigned long hpte_group,
144 unsigned long rflags,
145 unsigned long vflags,
146 int psize, int apsize,
148 long (*hpte_remove)(unsigned long hpte_group);
149 int (*hpte_removebolted)(unsigned long ea,
150 int psize, int ssize);
151 void (*flush_hash_range)(unsigned long number, int local);
152 void (*hugepage_invalidate)(unsigned long vsid,
154 unsigned char *hpte_slot_array,
155 int psize, int ssize, int local);
158 * To be called in real mode with interrupts disabled. No locks are
159 * taken as such, concurrent access on pre POWER5 hardware could result
161 * The linear mapping is destroyed as well.
163 void (*hpte_clear_all)(void);
165 extern struct mmu_hash_ops mmu_hash_ops;
172 extern struct hash_pte *htab_address;
173 extern unsigned long htab_size_bytes;
174 extern unsigned long htab_hash_mask;
177 static inline int shift_to_mmu_psize(unsigned int shift)
181 for (psize = 0; psize < MMU_PAGE_COUNT; ++psize)
182 if (mmu_psize_defs[psize].shift == shift)
187 static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize)
189 if (mmu_psize_defs[mmu_psize].shift)
190 return mmu_psize_defs[mmu_psize].shift;
194 static inline unsigned long get_sllp_encoding(int psize)
198 sllp = ((mmu_psize_defs[psize].sllp & SLB_VSID_L) >> 6) |
199 ((mmu_psize_defs[psize].sllp & SLB_VSID_LP) >> 4);
203 #endif /* __ASSEMBLY__ */
207 * These are the values used by hardware in the B field of
208 * SLB entries and the first dword of MMU hashtable entries.
209 * The B field is 2 bits; the values 2 and 3 are unused and reserved.
211 #define MMU_SEGSIZE_256M 0
212 #define MMU_SEGSIZE_1T 1
215 * encode page number shift.
216 * in order to fit the 78 bit va in a 64 bit variable we shift the va by
217 * 12 bits. This enable us to address upto 76 bit va.
218 * For hpt hash from a va we can ignore the page size bits of va and for
219 * hpte encoding we ignore up to 23 bits of va. So ignoring lower 12 bits ensure
220 * we work in all cases including 4k page size.
225 * HPTE Large Page (LP) details
229 #define LP_MASK(i) ((0xFF >> (i)) << LP_SHIFT)
233 static inline int slb_vsid_shift(int ssize)
235 if (ssize == MMU_SEGSIZE_256M)
236 return SLB_VSID_SHIFT;
237 return SLB_VSID_SHIFT_1T;
240 static inline int segment_shift(int ssize)
242 if (ssize == MMU_SEGSIZE_256M)
248 * This array is indexed by the LP field of the HPTE second dword.
249 * Since this field may contain some RPN bits, some entries are
250 * replicated so that we get the same value irrespective of RPN.
251 * The top 4 bits are the page size index (MMU_PAGE_*) for the
252 * actual page size, the bottom 4 bits are the base page size.
254 extern u8 hpte_page_sizes[1 << LP_BITS];
256 static inline unsigned long __hpte_page_size(unsigned long h, unsigned long l,
261 if (!(h & HPTE_V_LARGE))
264 /* Look at the 8 bit LP value */
265 lp = (l >> LP_SHIFT) & ((1 << LP_BITS) - 1);
266 i = hpte_page_sizes[lp];
271 return 1ul << mmu_psize_defs[i & 0xf].shift;
274 static inline unsigned long hpte_page_size(unsigned long h, unsigned long l)
276 return __hpte_page_size(h, l, 0);
279 static inline unsigned long hpte_base_page_size(unsigned long h, unsigned long l)
281 return __hpte_page_size(h, l, 1);
285 * The current system page and segment sizes
287 extern int mmu_kernel_ssize;
288 extern int mmu_highuser_ssize;
289 extern u16 mmu_slb_size;
290 extern unsigned long tce_alloc_start, tce_alloc_end;
293 * If the processor supports 64k normal pages but not 64k cache
294 * inhibited pages, we have to be prepared to switch processes
295 * to use 4k pages when they create cache-inhibited mappings.
296 * If this is the case, mmu_ci_restrictions will be set to 1.
298 extern int mmu_ci_restrictions;
301 * This computes the AVPN and B fields of the first dword of a HPTE,
302 * for use when we want to match an existing PTE. The bottom 7 bits
303 * of the returned value are zero.
305 static inline unsigned long hpte_encode_avpn(unsigned long vpn, int psize,
310 * The AVA field omits the low-order 23 bits of the 78 bits VA.
311 * These bits are not needed in the PTE, because the
312 * low-order b of these bits are part of the byte offset
313 * into the virtual page and, if b < 23, the high-order
314 * 23-b of these bits are always used in selecting the
315 * PTEGs to be searched
317 v = (vpn >> (23 - VPN_SHIFT)) & ~(mmu_psize_defs[psize].avpnm);
318 v <<= HPTE_V_AVPN_SHIFT;
319 if (!cpu_has_feature(CPU_FTR_ARCH_300))
320 v |= ((unsigned long) ssize) << HPTE_V_SSIZE_SHIFT;
325 * This function sets the AVPN and L fields of the HPTE appropriately
326 * using the base page size and actual page size.
328 static inline unsigned long hpte_encode_v(unsigned long vpn, int base_psize,
329 int actual_psize, int ssize)
332 v = hpte_encode_avpn(vpn, base_psize, ssize);
333 if (actual_psize != MMU_PAGE_4K)
339 * This function sets the ARPN, and LP fields of the HPTE appropriately
340 * for the page size. We assume the pa is already "clean" that is properly
341 * aligned for the requested page size
343 static inline unsigned long hpte_encode_r(unsigned long pa, int base_psize,
344 int actual_psize, int ssize)
347 if (cpu_has_feature(CPU_FTR_ARCH_300))
348 pa |= ((unsigned long) ssize) << HPTE_R_3_0_SSIZE_SHIFT;
350 /* A 4K page needs no special encoding */
351 if (actual_psize == MMU_PAGE_4K)
352 return pa & HPTE_R_RPN;
354 unsigned int penc = mmu_psize_defs[base_psize].penc[actual_psize];
355 unsigned int shift = mmu_psize_defs[actual_psize].shift;
356 return (pa & ~((1ul << shift) - 1)) | (penc << LP_SHIFT);
361 * Build a VPN_SHIFT bit shifted va given VSID, EA and segment size.
363 static inline unsigned long hpt_vpn(unsigned long ea,
364 unsigned long vsid, int ssize)
367 int s_shift = segment_shift(ssize);
369 mask = (1ul << (s_shift - VPN_SHIFT)) - 1;
370 return (vsid << (s_shift - VPN_SHIFT)) | ((ea >> VPN_SHIFT) & mask);
374 * This hashes a virtual address
376 static inline unsigned long hpt_hash(unsigned long vpn,
377 unsigned int shift, int ssize)
380 unsigned long hash, vsid;
382 /* VPN_SHIFT can be atmost 12 */
383 if (ssize == MMU_SEGSIZE_256M) {
384 mask = (1ul << (SID_SHIFT - VPN_SHIFT)) - 1;
385 hash = (vpn >> (SID_SHIFT - VPN_SHIFT)) ^
386 ((vpn & mask) >> (shift - VPN_SHIFT));
388 mask = (1ul << (SID_SHIFT_1T - VPN_SHIFT)) - 1;
389 vsid = vpn >> (SID_SHIFT_1T - VPN_SHIFT);
390 hash = vsid ^ (vsid << 25) ^
391 ((vpn & mask) >> (shift - VPN_SHIFT)) ;
393 return hash & 0x7fffffffffUL;
396 #define HPTE_LOCAL_UPDATE 0x1
397 #define HPTE_NOHPTE_UPDATE 0x2
399 extern int __hash_page_4K(unsigned long ea, unsigned long access,
400 unsigned long vsid, pte_t *ptep, unsigned long trap,
401 unsigned long flags, int ssize, int subpage_prot);
402 extern int __hash_page_64K(unsigned long ea, unsigned long access,
403 unsigned long vsid, pte_t *ptep, unsigned long trap,
404 unsigned long flags, int ssize);
406 unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap);
407 extern int hash_page_mm(struct mm_struct *mm, unsigned long ea,
408 unsigned long access, unsigned long trap,
409 unsigned long flags);
410 extern int hash_page(unsigned long ea, unsigned long access, unsigned long trap,
411 unsigned long dsisr);
412 int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
413 pte_t *ptep, unsigned long trap, unsigned long flags,
414 int ssize, unsigned int shift, unsigned int mmu_psize);
415 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
416 extern int __hash_page_thp(unsigned long ea, unsigned long access,
417 unsigned long vsid, pmd_t *pmdp, unsigned long trap,
418 unsigned long flags, int ssize, unsigned int psize);
420 static inline int __hash_page_thp(unsigned long ea, unsigned long access,
421 unsigned long vsid, pmd_t *pmdp,
422 unsigned long trap, unsigned long flags,
423 int ssize, unsigned int psize)
429 extern void hash_failure_debug(unsigned long ea, unsigned long access,
430 unsigned long vsid, unsigned long trap,
431 int ssize, int psize, int lpsize,
433 extern int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
434 unsigned long pstart, unsigned long prot,
435 int psize, int ssize);
436 int htab_remove_mapping(unsigned long vstart, unsigned long vend,
437 int psize, int ssize);
438 extern void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages);
439 extern void demote_segment_4k(struct mm_struct *mm, unsigned long addr);
441 #ifdef CONFIG_PPC_PSERIES
442 void hpte_init_pseries(void);
444 static inline void hpte_init_pseries(void) { }
447 extern void hpte_init_native(void);
449 extern void slb_initialize(void);
450 extern void slb_flush_and_rebolt(void);
452 extern void slb_vmalloc_update(void);
453 extern void slb_set_size(u16 size);
454 #endif /* __ASSEMBLY__ */
457 * VSID allocation (256MB segment)
459 * We first generate a 37-bit "proto-VSID". Proto-VSIDs are generated
460 * from mmu context id and effective segment id of the address.
462 * For user processes max context id is limited to ((1ul << 19) - 5)
463 * for kernel space, we use the top 4 context ids to map address as below
464 * NOTE: each context only support 64TB now.
465 * 0x7fffc - [ 0xc000000000000000 - 0xc0003fffffffffff ]
466 * 0x7fffd - [ 0xd000000000000000 - 0xd0003fffffffffff ]
467 * 0x7fffe - [ 0xe000000000000000 - 0xe0003fffffffffff ]
468 * 0x7ffff - [ 0xf000000000000000 - 0xf0003fffffffffff ]
470 * The proto-VSIDs are then scrambled into real VSIDs with the
471 * multiplicative hash:
473 * VSID = (proto-VSID * VSID_MULTIPLIER) % VSID_MODULUS
475 * VSID_MULTIPLIER is prime, so in particular it is
476 * co-prime to VSID_MODULUS, making this a 1:1 scrambling function.
477 * Because the modulus is 2^n-1 we can compute it efficiently without
478 * a divide or extra multiply (see below). The scramble function gives
479 * robust scattering in the hash table (at least based on some initial
482 * We also consider VSID 0 special. We use VSID 0 for slb entries mapping
483 * bad address. This enables us to consolidate bad address handling in
486 * We also need to avoid the last segment of the last context, because that
487 * would give a protovsid of 0x1fffffffff. That will result in a VSID 0
488 * because of the modulo operation in vsid scramble. But the vmemmap
489 * (which is what uses region 0xf) will never be close to 64TB in size
490 * (it's 56 bytes per page of system memory).
493 #define CONTEXT_BITS 19
495 #define ESID_BITS_1T 6
499 * The proto-VSID space has 2^(CONTEX_BITS + ESID_BITS) - 1 segments
500 * available for user + kernel mapping. The top 4 contexts are used for
501 * kernel mapping. Each segment contains 2^28 bytes. Each
502 * context maps 2^46 bytes (64TB) so we can support 2^19-1 contexts
503 * (19 == 37 + 28 - 46).
505 #define MAX_USER_CONTEXT ((ASM_CONST(1) << CONTEXT_BITS) - 5)
508 * This should be computed such that protovosid * vsid_mulitplier
509 * doesn't overflow 64 bits. It should also be co-prime to vsid_modulus
511 #define VSID_MULTIPLIER_256M ASM_CONST(12538073) /* 24-bit prime */
512 #define VSID_BITS_256M (CONTEXT_BITS + ESID_BITS)
513 #define VSID_MODULUS_256M ((1UL<<VSID_BITS_256M)-1)
515 #define VSID_MULTIPLIER_1T ASM_CONST(12538073) /* 24-bit prime */
516 #define VSID_BITS_1T (CONTEXT_BITS + ESID_BITS_1T)
517 #define VSID_MODULUS_1T ((1UL<<VSID_BITS_1T)-1)
520 #define USER_VSID_RANGE (1UL << (ESID_BITS + SID_SHIFT))
523 * This macro generates asm code to compute the VSID scramble
524 * function. Used in slb_allocate() and do_stab_bolted. The function
525 * computed is: (protovsid*VSID_MULTIPLIER) % VSID_MODULUS
527 * rt = register containing the proto-VSID and into which the
528 * VSID will be stored
529 * rx = scratch register (clobbered)
531 * - rt and rx must be different registers
532 * - The answer will end up in the low VSID_BITS bits of rt. The higher
533 * bits may contain other garbage, so you may need to mask the
536 #define ASM_VSID_SCRAMBLE(rt, rx, size) \
537 lis rx,VSID_MULTIPLIER_##size@h; \
538 ori rx,rx,VSID_MULTIPLIER_##size@l; \
539 mulld rt,rt,rx; /* rt = rt * MULTIPLIER */ \
541 srdi rx,rt,VSID_BITS_##size; \
542 clrldi rt,rt,(64-VSID_BITS_##size); \
543 add rt,rt,rx; /* add high and low bits */ \
544 /* NOTE: explanation based on VSID_BITS_##size = 36 \
545 * Now, r3 == VSID (mod 2^36-1), and lies between 0 and \
546 * 2^36-1+2^28-1. That in particular means that if r3 >= \
547 * 2^36-1, then r3+1 has the 2^36 bit set. So, if r3+1 has \
548 * the bit clear, r3 already has the answer we want, if it \
549 * doesn't, the answer is the low 36 bits of r3+1. So in all \
550 * cases the answer is the low 36 bits of (r3 + ((r3+1) >> 36))*/\
552 srdi rx,rx,VSID_BITS_##size; /* extract 2^VSID_BITS bit */ \
555 /* 4 bits per slice and we have one slice per 1TB */
556 #define SLICE_ARRAY_SIZE (H_PGTABLE_RANGE >> 41)
560 #ifdef CONFIG_PPC_SUBPAGE_PROT
562 * For the sub-page protection option, we extend the PGD with one of
563 * these. Basically we have a 3-level tree, with the top level being
564 * the protptrs array. To optimize speed and memory consumption when
565 * only addresses < 4GB are being protected, pointers to the first
566 * four pages of sub-page protection words are stored in the low_prot
568 * Each page of sub-page protection words protects 1GB (4 bytes
569 * protects 64k). For the 3-level tree, each page of pointers then
572 struct subpage_prot_table {
573 unsigned long maxaddr; /* only addresses < this are protected */
574 unsigned int **protptrs[(TASK_SIZE_USER64 >> 43)];
575 unsigned int *low_prot[4];
578 #define SBP_L1_BITS (PAGE_SHIFT - 2)
579 #define SBP_L2_BITS (PAGE_SHIFT - 3)
580 #define SBP_L1_COUNT (1 << SBP_L1_BITS)
581 #define SBP_L2_COUNT (1 << SBP_L2_BITS)
582 #define SBP_L2_SHIFT (PAGE_SHIFT + SBP_L1_BITS)
583 #define SBP_L3_SHIFT (SBP_L2_SHIFT + SBP_L2_BITS)
585 extern void subpage_prot_free(struct mm_struct *mm);
586 extern void subpage_prot_init_new_context(struct mm_struct *mm);
588 static inline void subpage_prot_free(struct mm_struct *mm) {}
589 static inline void subpage_prot_init_new_context(struct mm_struct *mm) { }
590 #endif /* CONFIG_PPC_SUBPAGE_PROT */
594 * The code below is equivalent to this function for arguments
595 * < 2^VSID_BITS, which is all this should ever be called
596 * with. However gcc is not clever enough to compute the
597 * modulus (2^n-1) without a second multiply.
599 #define vsid_scramble(protovsid, size) \
600 ((((protovsid) * VSID_MULTIPLIER_##size) % VSID_MODULUS_##size))
603 #define vsid_scramble(protovsid, size) \
606 x = (protovsid) * VSID_MULTIPLIER_##size; \
607 x = (x >> VSID_BITS_##size) + (x & VSID_MODULUS_##size); \
608 (x + ((x+1) >> VSID_BITS_##size)) & VSID_MODULUS_##size; \
612 /* Returns the segment size indicator for a user address */
613 static inline int user_segment_size(unsigned long addr)
615 /* Use 1T segments if possible for addresses >= 1T */
616 if (addr >= (1UL << SID_SHIFT_1T))
617 return mmu_highuser_ssize;
618 return MMU_SEGSIZE_256M;
621 static inline unsigned long get_vsid(unsigned long context, unsigned long ea,
625 * Bad address. We return VSID 0 for that
627 if ((ea & ~REGION_MASK) >= H_PGTABLE_RANGE)
630 if (ssize == MMU_SEGSIZE_256M)
631 return vsid_scramble((context << ESID_BITS)
632 | (ea >> SID_SHIFT), 256M);
633 return vsid_scramble((context << ESID_BITS_1T)
634 | (ea >> SID_SHIFT_1T), 1T);
638 * This is only valid for addresses >= PAGE_OFFSET
640 * For kernel space, we use the top 4 context ids to map address as below
641 * 0x7fffc - [ 0xc000000000000000 - 0xc0003fffffffffff ]
642 * 0x7fffd - [ 0xd000000000000000 - 0xd0003fffffffffff ]
643 * 0x7fffe - [ 0xe000000000000000 - 0xe0003fffffffffff ]
644 * 0x7ffff - [ 0xf000000000000000 - 0xf0003fffffffffff ]
646 static inline unsigned long get_kernel_vsid(unsigned long ea, int ssize)
648 unsigned long context;
651 * kernel take the top 4 context from the available range
653 context = (MAX_USER_CONTEXT) + ((ea >> 60) - 0xc) + 1;
654 return get_vsid(context, ea, ssize);
657 unsigned htab_shift_for_mem_size(unsigned long mem_size);
659 #endif /* __ASSEMBLY__ */
661 #endif /* _ASM_POWERPC_BOOK3S_64_MMU_HASH_H_ */