Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * PowerPC memory management structures |
| 3 | * |
| 4 | * Dave Engebretsen & Mike Corrigan <{engebret|mikejc}@us.ibm.com> |
| 5 | * PPC64 rework. |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version |
| 10 | * 2 of the License, or (at your option) any later version. |
| 11 | */ |
| 12 | |
| 13 | #ifndef _PPC64_MMU_H_ |
| 14 | #define _PPC64_MMU_H_ |
| 15 | |
| 16 | #include <linux/config.h> |
| 17 | #include <asm/page.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 19 | /* |
| 20 | * Segment table |
| 21 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | |
| 23 | #define STE_ESID_V 0x80 |
| 24 | #define STE_ESID_KS 0x20 |
| 25 | #define STE_ESID_KP 0x10 |
| 26 | #define STE_ESID_N 0x08 |
| 27 | |
| 28 | #define STE_VSID_SHIFT 12 |
| 29 | |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 30 | /* Location of cpu0's segment table */ |
| 31 | #define STAB0_PAGE 0x9 |
| 32 | #define STAB0_PHYS_ADDR (STAB0_PAGE<<PAGE_SHIFT) |
| 33 | #define STAB0_VIRT_ADDR (KERNELBASE+STAB0_PHYS_ADDR) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 35 | /* |
| 36 | * SLB |
| 37 | */ |
| 38 | |
| 39 | #define SLB_NUM_BOLTED 3 |
| 40 | #define SLB_CACHE_ENTRIES 8 |
| 41 | |
| 42 | /* Bits in the SLB ESID word */ |
| 43 | #define SLB_ESID_V ASM_CONST(0x0000000008000000) /* valid */ |
| 44 | |
| 45 | /* Bits in the SLB VSID word */ |
| 46 | #define SLB_VSID_SHIFT 12 |
| 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 */ |
Arnd Bergmann | fef1c77 | 2005-06-23 09:43:37 +1000 | [diff] [blame] | 50 | #define SLB_VSID_L ASM_CONST(0x0000000000000100) /* largepage */ |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 51 | #define SLB_VSID_C ASM_CONST(0x0000000000000080) /* class */ |
Arnd Bergmann | fef1c77 | 2005-06-23 09:43:37 +1000 | [diff] [blame] | 52 | #define SLB_VSID_LS ASM_CONST(0x0000000000000070) /* size of largepage */ |
| 53 | |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 54 | #define SLB_VSID_KERNEL (SLB_VSID_KP|SLB_VSID_C) |
| 55 | #define SLB_VSID_USER (SLB_VSID_KP|SLB_VSID_KS) |
| 56 | |
| 57 | /* |
| 58 | * Hash table |
| 59 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | |
| 61 | #define HPTES_PER_GROUP 8 |
| 62 | |
David Gibson | 96e2844 | 2005-07-13 01:11:42 -0700 | [diff] [blame] | 63 | #define HPTE_V_AVPN_SHIFT 7 |
| 64 | #define HPTE_V_AVPN ASM_CONST(0xffffffffffffff80) |
| 65 | #define HPTE_V_AVPN_VAL(x) (((x) & HPTE_V_AVPN) >> HPTE_V_AVPN_SHIFT) |
| 66 | #define HPTE_V_BOLTED ASM_CONST(0x0000000000000010) |
| 67 | #define HPTE_V_LOCK ASM_CONST(0x0000000000000008) |
| 68 | #define HPTE_V_LARGE ASM_CONST(0x0000000000000004) |
| 69 | #define HPTE_V_SECONDARY ASM_CONST(0x0000000000000002) |
| 70 | #define HPTE_V_VALID ASM_CONST(0x0000000000000001) |
| 71 | |
| 72 | #define HPTE_R_PP0 ASM_CONST(0x8000000000000000) |
| 73 | #define HPTE_R_TS ASM_CONST(0x4000000000000000) |
| 74 | #define HPTE_R_RPN_SHIFT 12 |
| 75 | #define HPTE_R_RPN ASM_CONST(0x3ffffffffffff000) |
| 76 | #define HPTE_R_FLAGS ASM_CONST(0x00000000000003ff) |
| 77 | #define HPTE_R_PP ASM_CONST(0x0000000000000003) |
| 78 | |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 79 | /* Values for PP (assumes Ks=0, Kp=1) */ |
| 80 | /* pp0 will always be 0 for linux */ |
| 81 | #define PP_RWXX 0 /* Supervisor read/write, User none */ |
| 82 | #define PP_RWRX 1 /* Supervisor read/write, User read */ |
| 83 | #define PP_RWRW 2 /* Supervisor read/write, User read/write */ |
| 84 | #define PP_RXRX 3 /* Supervisor read, User read */ |
| 85 | |
| 86 | #ifndef __ASSEMBLY__ |
| 87 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | typedef struct { |
David Gibson | 96e2844 | 2005-07-13 01:11:42 -0700 | [diff] [blame] | 89 | unsigned long v; |
| 90 | unsigned long r; |
| 91 | } hpte_t; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | |
David Gibson | 96e2844 | 2005-07-13 01:11:42 -0700 | [diff] [blame] | 93 | extern hpte_t *htab_address; |
| 94 | extern unsigned long htab_hash_mask; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | |
| 96 | static inline unsigned long hpt_hash(unsigned long vpn, int large) |
| 97 | { |
| 98 | unsigned long vsid; |
| 99 | unsigned long page; |
| 100 | |
| 101 | if (large) { |
| 102 | vsid = vpn >> 4; |
| 103 | page = vpn & 0xf; |
| 104 | } else { |
| 105 | vsid = vpn >> 16; |
| 106 | page = vpn & 0xffff; |
| 107 | } |
| 108 | |
| 109 | return (vsid & 0x7fffffffffUL) ^ page; |
| 110 | } |
| 111 | |
| 112 | static inline void __tlbie(unsigned long va, int large) |
| 113 | { |
| 114 | /* clear top 16 bits, non SLS segment */ |
| 115 | va &= ~(0xffffULL << 48); |
| 116 | |
| 117 | if (large) { |
| 118 | va &= HPAGE_MASK; |
| 119 | asm volatile("tlbie %0,1" : : "r"(va) : "memory"); |
| 120 | } else { |
| 121 | va &= PAGE_MASK; |
| 122 | asm volatile("tlbie %0,0" : : "r"(va) : "memory"); |
| 123 | } |
| 124 | } |
| 125 | |
| 126 | static inline void tlbie(unsigned long va, int large) |
| 127 | { |
| 128 | asm volatile("ptesync": : :"memory"); |
| 129 | __tlbie(va, large); |
| 130 | asm volatile("eieio; tlbsync; ptesync": : :"memory"); |
| 131 | } |
| 132 | |
| 133 | static inline void __tlbiel(unsigned long va) |
| 134 | { |
| 135 | /* clear top 16 bits, non SLS segment */ |
| 136 | va &= ~(0xffffULL << 48); |
| 137 | va &= PAGE_MASK; |
| 138 | |
| 139 | /* |
| 140 | * Thanks to Alan Modra we are now able to use machine specific |
| 141 | * assembly instructions (like tlbiel) by using the gas -many flag. |
| 142 | * However we have to support older toolchains so for the moment |
| 143 | * we hardwire it. |
| 144 | */ |
| 145 | #if 0 |
| 146 | asm volatile("tlbiel %0" : : "r"(va) : "memory"); |
| 147 | #else |
| 148 | asm volatile(".long 0x7c000224 | (%0 << 11)" : : "r"(va) : "memory"); |
| 149 | #endif |
| 150 | } |
| 151 | |
| 152 | static inline void tlbiel(unsigned long va) |
| 153 | { |
| 154 | asm volatile("ptesync": : :"memory"); |
| 155 | __tlbiel(va); |
| 156 | asm volatile("ptesync": : :"memory"); |
| 157 | } |
| 158 | |
David Gibson | 96e2844 | 2005-07-13 01:11:42 -0700 | [diff] [blame] | 159 | static inline unsigned long slot2va(unsigned long hpte_v, unsigned long slot) |
R Sharada | f4c82d5 | 2005-06-25 14:58:08 -0700 | [diff] [blame] | 160 | { |
David Gibson | 96e2844 | 2005-07-13 01:11:42 -0700 | [diff] [blame] | 161 | unsigned long avpn = HPTE_V_AVPN_VAL(hpte_v); |
R Sharada | f4c82d5 | 2005-06-25 14:58:08 -0700 | [diff] [blame] | 162 | unsigned long va; |
| 163 | |
| 164 | va = avpn << 23; |
| 165 | |
David Gibson | 96e2844 | 2005-07-13 01:11:42 -0700 | [diff] [blame] | 166 | if (! (hpte_v & HPTE_V_LARGE)) { |
R Sharada | f4c82d5 | 2005-06-25 14:58:08 -0700 | [diff] [blame] | 167 | unsigned long vpi, pteg; |
| 168 | |
| 169 | pteg = slot / HPTES_PER_GROUP; |
David Gibson | 96e2844 | 2005-07-13 01:11:42 -0700 | [diff] [blame] | 170 | if (hpte_v & HPTE_V_SECONDARY) |
R Sharada | f4c82d5 | 2005-06-25 14:58:08 -0700 | [diff] [blame] | 171 | pteg = ~pteg; |
| 172 | |
| 173 | vpi = ((va >> 28) ^ pteg) & htab_hash_mask; |
| 174 | |
| 175 | va |= vpi << PAGE_SHIFT; |
| 176 | } |
| 177 | |
| 178 | return va; |
| 179 | } |
| 180 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | /* |
| 182 | * Handle a fault by adding an HPTE. If the address can't be determined |
| 183 | * to be valid via Linux page tables, return 1. If handled return 0 |
| 184 | */ |
| 185 | extern int __hash_page(unsigned long ea, unsigned long access, |
| 186 | unsigned long vsid, pte_t *ptep, unsigned long trap, |
| 187 | int local); |
| 188 | |
| 189 | extern void htab_finish_init(void); |
| 190 | |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 191 | extern void hpte_init_native(void); |
| 192 | extern void hpte_init_lpar(void); |
| 193 | extern void hpte_init_iSeries(void); |
| 194 | |
| 195 | extern long pSeries_lpar_hpte_insert(unsigned long hpte_group, |
| 196 | unsigned long va, unsigned long prpn, |
David Gibson | 96e2844 | 2005-07-13 01:11:42 -0700 | [diff] [blame] | 197 | unsigned long vflags, |
| 198 | unsigned long rflags); |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 199 | extern long native_hpte_insert(unsigned long hpte_group, unsigned long va, |
David Gibson | 96e2844 | 2005-07-13 01:11:42 -0700 | [diff] [blame] | 200 | unsigned long prpn, |
| 201 | unsigned long vflags, unsigned long rflags); |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 202 | |
David Gibson | 533f081 | 2005-07-27 11:44:19 -0700 | [diff] [blame^] | 203 | extern void stabs_alloc(void); |
| 204 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | #endif /* __ASSEMBLY__ */ |
| 206 | |
| 207 | /* |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 208 | * VSID allocation |
| 209 | * |
| 210 | * We first generate a 36-bit "proto-VSID". For kernel addresses this |
| 211 | * is equal to the ESID, for user addresses it is: |
| 212 | * (context << 15) | (esid & 0x7fff) |
| 213 | * |
| 214 | * The two forms are distinguishable because the top bit is 0 for user |
| 215 | * addresses, whereas the top two bits are 1 for kernel addresses. |
| 216 | * Proto-VSIDs with the top two bits equal to 0b10 are reserved for |
| 217 | * now. |
| 218 | * |
| 219 | * The proto-VSIDs are then scrambled into real VSIDs with the |
| 220 | * multiplicative hash: |
| 221 | * |
| 222 | * VSID = (proto-VSID * VSID_MULTIPLIER) % VSID_MODULUS |
| 223 | * where VSID_MULTIPLIER = 268435399 = 0xFFFFFC7 |
| 224 | * VSID_MODULUS = 2^36-1 = 0xFFFFFFFFF |
| 225 | * |
| 226 | * This scramble is only well defined for proto-VSIDs below |
| 227 | * 0xFFFFFFFFF, so both proto-VSID and actual VSID 0xFFFFFFFFF are |
| 228 | * reserved. VSID_MULTIPLIER is prime, so in particular it is |
| 229 | * co-prime to VSID_MODULUS, making this a 1:1 scrambling function. |
| 230 | * Because the modulus is 2^n-1 we can compute it efficiently without |
| 231 | * a divide or extra multiply (see below). |
| 232 | * |
| 233 | * This scheme has several advantages over older methods: |
| 234 | * |
| 235 | * - We have VSIDs allocated for every kernel address |
| 236 | * (i.e. everything above 0xC000000000000000), except the very top |
| 237 | * segment, which simplifies several things. |
| 238 | * |
| 239 | * - We allow for 15 significant bits of ESID and 20 bits of |
| 240 | * context for user addresses. i.e. 8T (43 bits) of address space for |
| 241 | * up to 1M contexts (although the page table structure and context |
| 242 | * allocation will need changes to take advantage of this). |
| 243 | * |
| 244 | * - The scramble function gives robust scattering in the hash |
| 245 | * table (at least based on some initial results). The previous |
| 246 | * method was more susceptible to pathological cases giving excessive |
| 247 | * hash collisions. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 248 | */ |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 249 | /* |
| 250 | * WARNING - If you change these you must make sure the asm |
| 251 | * implementations in slb_allocate (slb_low.S), do_stab_bolted |
| 252 | * (head.S) and ASM_VSID_SCRAMBLE (below) are changed accordingly. |
| 253 | * |
| 254 | * You'll also need to change the precomputed VSID values in head.S |
| 255 | * which are used by the iSeries firmware. |
| 256 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | |
| 258 | #define VSID_MULTIPLIER ASM_CONST(200730139) /* 28-bit prime */ |
| 259 | #define VSID_BITS 36 |
| 260 | #define VSID_MODULUS ((1UL<<VSID_BITS)-1) |
| 261 | |
| 262 | #define CONTEXT_BITS 20 |
| 263 | #define USER_ESID_BITS 15 |
| 264 | |
| 265 | /* |
| 266 | * This macro generates asm code to compute the VSID scramble |
| 267 | * function. Used in slb_allocate() and do_stab_bolted. The function |
| 268 | * computed is: (protovsid*VSID_MULTIPLIER) % VSID_MODULUS |
| 269 | * |
| 270 | * rt = register continaing the proto-VSID and into which the |
| 271 | * VSID will be stored |
| 272 | * rx = scratch register (clobbered) |
| 273 | * |
| 274 | * - rt and rx must be different registers |
| 275 | * - The answer will end up in the low 36 bits of rt. The higher |
| 276 | * bits may contain other garbage, so you may need to mask the |
| 277 | * result. |
| 278 | */ |
| 279 | #define ASM_VSID_SCRAMBLE(rt, rx) \ |
| 280 | lis rx,VSID_MULTIPLIER@h; \ |
| 281 | ori rx,rx,VSID_MULTIPLIER@l; \ |
| 282 | mulld rt,rt,rx; /* rt = rt * MULTIPLIER */ \ |
| 283 | \ |
| 284 | srdi rx,rt,VSID_BITS; \ |
| 285 | clrldi rt,rt,(64-VSID_BITS); \ |
| 286 | add rt,rt,rx; /* add high and low bits */ \ |
| 287 | /* Now, r3 == VSID (mod 2^36-1), and lies between 0 and \ |
| 288 | * 2^36-1+2^28-1. That in particular means that if r3 >= \ |
| 289 | * 2^36-1, then r3+1 has the 2^36 bit set. So, if r3+1 has \ |
| 290 | * the bit clear, r3 already has the answer we want, if it \ |
| 291 | * doesn't, the answer is the low 36 bits of r3+1. So in all \ |
| 292 | * cases the answer is the low 36 bits of (r3 + ((r3+1) >> 36))*/\ |
| 293 | addi rx,rt,1; \ |
| 294 | srdi rx,rx,VSID_BITS; /* extract 2^36 bit */ \ |
| 295 | add rt,rt,rx |
| 296 | |
David Gibson | 1f8d419 | 2005-05-05 16:15:13 -0700 | [diff] [blame] | 297 | |
| 298 | #ifndef __ASSEMBLY__ |
| 299 | |
| 300 | typedef unsigned long mm_context_id_t; |
| 301 | |
| 302 | typedef struct { |
| 303 | mm_context_id_t id; |
| 304 | #ifdef CONFIG_HUGETLB_PAGE |
| 305 | pgd_t *huge_pgdir; |
| 306 | u16 htlb_segs; /* bitmask */ |
| 307 | #endif |
| 308 | } mm_context_t; |
| 309 | |
| 310 | |
| 311 | static inline unsigned long vsid_scramble(unsigned long protovsid) |
| 312 | { |
| 313 | #if 0 |
| 314 | /* The code below is equivalent to this function for arguments |
| 315 | * < 2^VSID_BITS, which is all this should ever be called |
| 316 | * with. However gcc is not clever enough to compute the |
| 317 | * modulus (2^n-1) without a second multiply. */ |
| 318 | return ((protovsid * VSID_MULTIPLIER) % VSID_MODULUS); |
| 319 | #else /* 1 */ |
| 320 | unsigned long x; |
| 321 | |
| 322 | x = protovsid * VSID_MULTIPLIER; |
| 323 | x = (x >> VSID_BITS) + (x & VSID_MODULUS); |
| 324 | return (x + ((x+1) >> VSID_BITS)) & VSID_MODULUS; |
| 325 | #endif /* 1 */ |
| 326 | } |
| 327 | |
| 328 | /* This is only valid for addresses >= KERNELBASE */ |
| 329 | static inline unsigned long get_kernel_vsid(unsigned long ea) |
| 330 | { |
| 331 | return vsid_scramble(ea >> SID_SHIFT); |
| 332 | } |
| 333 | |
| 334 | /* This is only valid for user addresses (which are below 2^41) */ |
| 335 | static inline unsigned long get_vsid(unsigned long context, unsigned long ea) |
| 336 | { |
| 337 | return vsid_scramble((context << USER_ESID_BITS) |
| 338 | | (ea >> SID_SHIFT)); |
| 339 | } |
| 340 | |
| 341 | #endif /* __ASSEMBLY */ |
| 342 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 343 | #endif /* _PPC64_MMU_H_ */ |