Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 1 | /* |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 2 | * PowerPC version |
| 3 | * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) |
| 4 | * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP |
| 5 | * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu> |
| 6 | * Adapted for Power Macintosh by Paul Mackerras. |
| 7 | * Low-level exception handlers and MMU support |
| 8 | * rewritten by Paul Mackerras. |
| 9 | * Copyright (C) 1996 Paul Mackerras. |
| 10 | * |
| 11 | * This file contains low-level assembler routines for managing |
| 12 | * the PowerPC MMU hash table. (PPC 8xx processors don't use a |
| 13 | * hash table, so this file is not used on them.) |
| 14 | * |
| 15 | * This program is free software; you can redistribute it and/or |
| 16 | * modify it under the terms of the GNU General Public License |
| 17 | * as published by the Free Software Foundation; either version |
| 18 | * 2 of the License, or (at your option) any later version. |
| 19 | * |
| 20 | */ |
| 21 | |
Paul Mackerras | b3b8dc6 | 2005-10-10 22:20:10 +1000 | [diff] [blame] | 22 | #include <asm/reg.h> |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 23 | #include <asm/page.h> |
| 24 | #include <asm/pgtable.h> |
| 25 | #include <asm/cputable.h> |
| 26 | #include <asm/ppc_asm.h> |
| 27 | #include <asm/thread_info.h> |
| 28 | #include <asm/asm-offsets.h> |
| 29 | |
| 30 | #ifdef CONFIG_SMP |
Kumar Gala | 991eb43 | 2007-05-14 17:11:58 -0500 | [diff] [blame] | 31 | .section .bss |
| 32 | .align 2 |
| 33 | .globl mmu_hash_lock |
| 34 | mmu_hash_lock: |
| 35 | .space 4 |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 36 | #endif /* CONFIG_SMP */ |
| 37 | |
| 38 | /* |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 39 | * Load a PTE into the hash table, if possible. |
| 40 | * The address is in r4, and r3 contains an access flag: |
| 41 | * _PAGE_RW (0x400) if a write. |
| 42 | * r9 contains the SRR1 value, from which we use the MSR_PR bit. |
| 43 | * SPRG3 contains the physical address of the current task's thread. |
| 44 | * |
| 45 | * Returns to the caller if the access is illegal or there is no |
| 46 | * mapping for the address. Otherwise it places an appropriate PTE |
| 47 | * in the hash table and returns from the exception. |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 48 | * Uses r0, r3 - r8, r10, ctr, lr. |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 49 | */ |
| 50 | .text |
| 51 | _GLOBAL(hash_page) |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 52 | tophys(r7,0) /* gets -KERNELBASE into r7 */ |
| 53 | #ifdef CONFIG_SMP |
| 54 | addis r8,r7,mmu_hash_lock@h |
| 55 | ori r8,r8,mmu_hash_lock@l |
| 56 | lis r0,0x0fff |
| 57 | b 10f |
| 58 | 11: lwz r6,0(r8) |
| 59 | cmpwi 0,r6,0 |
| 60 | bne 11b |
| 61 | 10: lwarx r6,0,r8 |
| 62 | cmpwi 0,r6,0 |
| 63 | bne- 11b |
| 64 | stwcx. r0,0,r8 |
| 65 | bne- 10b |
| 66 | isync |
| 67 | #endif |
| 68 | /* Get PTE (linux-style) and check access */ |
| 69 | lis r0,KERNELBASE@h /* check if kernel address */ |
| 70 | cmplw 0,r4,r0 |
| 71 | mfspr r8,SPRN_SPRG3 /* current task's THREAD (phys) */ |
| 72 | ori r3,r3,_PAGE_USER|_PAGE_PRESENT /* test low addresses as user */ |
| 73 | lwz r5,PGDIR(r8) /* virt page-table root */ |
| 74 | blt+ 112f /* assume user more likely */ |
| 75 | lis r5,swapper_pg_dir@ha /* if kernel address, use */ |
| 76 | addi r5,r5,swapper_pg_dir@l /* kernel page table */ |
| 77 | rlwimi r3,r9,32-12,29,29 /* MSR_PR -> _PAGE_USER */ |
| 78 | 112: add r5,r5,r7 /* convert to phys addr */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 79 | #ifndef CONFIG_PTE_64BIT |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 80 | rlwimi r5,r4,12,20,29 /* insert top 10 bits of address */ |
| 81 | lwz r8,0(r5) /* get pmd entry */ |
| 82 | rlwinm. r8,r8,0,0,19 /* extract address of pte page */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 83 | #else |
| 84 | rlwinm r8,r4,13,19,29 /* Compute pgdir/pmd offset */ |
| 85 | lwzx r8,r8,r5 /* Get L1 entry */ |
| 86 | rlwinm. r8,r8,0,0,20 /* extract pt base address */ |
| 87 | #endif |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 88 | #ifdef CONFIG_SMP |
| 89 | beq- hash_page_out /* return if no mapping */ |
| 90 | #else |
| 91 | /* XXX it seems like the 601 will give a machine fault on the |
| 92 | rfi if its alignment is wrong (bottom 4 bits of address are |
| 93 | 8 or 0xc) and we have had a not-taken conditional branch |
| 94 | to the address following the rfi. */ |
| 95 | beqlr- |
| 96 | #endif |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 97 | #ifndef CONFIG_PTE_64BIT |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 98 | rlwimi r8,r4,22,20,29 /* insert next 10 bits of address */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 99 | #else |
| 100 | rlwimi r8,r4,23,20,28 /* compute pte address */ |
| 101 | #endif |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 102 | rlwinm r0,r3,32-3,24,24 /* _PAGE_RW access -> _PAGE_DIRTY */ |
| 103 | ori r0,r0,_PAGE_ACCESSED|_PAGE_HASHPTE |
| 104 | |
| 105 | /* |
| 106 | * Update the linux PTE atomically. We do the lwarx up-front |
| 107 | * because almost always, there won't be a permission violation |
| 108 | * and there won't already be an HPTE, and thus we will have |
| 109 | * to update the PTE to set _PAGE_HASHPTE. -- paulus. |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 110 | * |
| 111 | * If PTE_64BIT is set, the low word is the flags word; use that |
| 112 | * word for locking since it contains all the interesting bits. |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 113 | */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 114 | #if (PTE_FLAGS_OFFSET != 0) |
| 115 | addi r8,r8,PTE_FLAGS_OFFSET |
| 116 | #endif |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 117 | retry: |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 118 | lwarx r6,0,r8 /* get linux-style pte, flag word */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 119 | andc. r5,r3,r6 /* check access & ~permission */ |
| 120 | #ifdef CONFIG_SMP |
| 121 | bne- hash_page_out /* return if access not permitted */ |
| 122 | #else |
| 123 | bnelr- |
| 124 | #endif |
| 125 | or r5,r0,r6 /* set accessed/dirty bits */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 126 | #ifdef CONFIG_PTE_64BIT |
| 127 | #ifdef CONFIG_SMP |
| 128 | subf r10,r6,r8 /* create false data dependency */ |
| 129 | subi r10,r10,PTE_FLAGS_OFFSET |
| 130 | lwzx r10,r6,r10 /* Get upper PTE word */ |
| 131 | #else |
| 132 | lwz r10,-PTE_FLAGS_OFFSET(r8) |
| 133 | #endif /* CONFIG_SMP */ |
| 134 | #endif /* CONFIG_PTE_64BIT */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 135 | stwcx. r5,0,r8 /* attempt to update PTE */ |
| 136 | bne- retry /* retry if someone got there first */ |
| 137 | |
| 138 | mfsrin r3,r4 /* get segment reg for segment */ |
| 139 | mfctr r0 |
| 140 | stw r0,_CTR(r11) |
| 141 | bl create_hpte /* add the hash table entry */ |
| 142 | |
| 143 | #ifdef CONFIG_SMP |
| 144 | eieio |
| 145 | addis r8,r7,mmu_hash_lock@ha |
| 146 | li r0,0 |
| 147 | stw r0,mmu_hash_lock@l(r8) |
| 148 | #endif |
| 149 | |
| 150 | /* Return from the exception */ |
| 151 | lwz r5,_CTR(r11) |
| 152 | mtctr r5 |
| 153 | lwz r0,GPR0(r11) |
| 154 | lwz r7,GPR7(r11) |
| 155 | lwz r8,GPR8(r11) |
| 156 | b fast_exception_return |
| 157 | |
| 158 | #ifdef CONFIG_SMP |
| 159 | hash_page_out: |
| 160 | eieio |
| 161 | addis r8,r7,mmu_hash_lock@ha |
| 162 | li r0,0 |
| 163 | stw r0,mmu_hash_lock@l(r8) |
| 164 | blr |
| 165 | #endif /* CONFIG_SMP */ |
| 166 | |
| 167 | /* |
| 168 | * Add an entry for a particular page to the hash table. |
| 169 | * |
| 170 | * add_hash_page(unsigned context, unsigned long va, unsigned long pmdval) |
| 171 | * |
| 172 | * We assume any necessary modifications to the pte (e.g. setting |
| 173 | * the accessed bit) have already been done and that there is actually |
| 174 | * a hash table in use (i.e. we're not on a 603). |
| 175 | */ |
| 176 | _GLOBAL(add_hash_page) |
| 177 | mflr r0 |
| 178 | stw r0,4(r1) |
| 179 | |
| 180 | /* Convert context and va to VSID */ |
| 181 | mulli r3,r3,897*16 /* multiply context by context skew */ |
| 182 | rlwinm r0,r4,4,28,31 /* get ESID (top 4 bits of va) */ |
| 183 | mulli r0,r0,0x111 /* multiply by ESID skew */ |
| 184 | add r3,r3,r0 /* note create_hpte trims to 24 bits */ |
| 185 | |
| 186 | #ifdef CONFIG_SMP |
Kumar Gala | f608600 | 2008-04-24 06:29:36 +1000 | [diff] [blame] | 187 | rlwinm r8,r1,0,0,(31-THREAD_SHIFT) /* use cpu number to make tag */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 188 | lwz r8,TI_CPU(r8) /* to go in mmu_hash_lock */ |
| 189 | oris r8,r8,12 |
| 190 | #endif /* CONFIG_SMP */ |
| 191 | |
| 192 | /* |
| 193 | * We disable interrupts here, even on UP, because we don't |
| 194 | * want to race with hash_page, and because we want the |
| 195 | * _PAGE_HASHPTE bit to be a reliable indication of whether |
| 196 | * the HPTE exists (or at least whether one did once). |
| 197 | * We also turn off the MMU for data accesses so that we |
| 198 | * we can't take a hash table miss (assuming the code is |
| 199 | * covered by a BAT). -- paulus |
| 200 | */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 201 | mfmsr r9 |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 202 | SYNC |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 203 | rlwinm r0,r9,0,17,15 /* clear bit 16 (MSR_EE) */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 204 | rlwinm r0,r0,0,28,26 /* clear MSR_DR */ |
| 205 | mtmsr r0 |
| 206 | SYNC_601 |
| 207 | isync |
| 208 | |
| 209 | tophys(r7,0) |
| 210 | |
| 211 | #ifdef CONFIG_SMP |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 212 | addis r6,r7,mmu_hash_lock@ha |
| 213 | addi r6,r6,mmu_hash_lock@l |
| 214 | 10: lwarx r0,0,r6 /* take the mmu_hash_lock */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 215 | cmpi 0,r0,0 |
| 216 | bne- 11f |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 217 | stwcx. r8,0,r6 |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 218 | beq+ 12f |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 219 | 11: lwz r0,0(r6) |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 220 | cmpi 0,r0,0 |
| 221 | beq 10b |
| 222 | b 11b |
| 223 | 12: isync |
| 224 | #endif |
| 225 | |
| 226 | /* |
| 227 | * Fetch the linux pte and test and set _PAGE_HASHPTE atomically. |
| 228 | * If _PAGE_HASHPTE was already set, we don't replace the existing |
| 229 | * HPTE, so we just unlock and return. |
| 230 | */ |
| 231 | mr r8,r5 |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 232 | #ifndef CONFIG_PTE_64BIT |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 233 | rlwimi r8,r4,22,20,29 |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 234 | #else |
| 235 | rlwimi r8,r4,23,20,28 |
| 236 | addi r8,r8,PTE_FLAGS_OFFSET |
| 237 | #endif |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 238 | 1: lwarx r6,0,r8 |
| 239 | andi. r0,r6,_PAGE_HASHPTE |
| 240 | bne 9f /* if HASHPTE already set, done */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 241 | #ifdef CONFIG_PTE_64BIT |
| 242 | #ifdef CONFIG_SMP |
| 243 | subf r10,r6,r8 /* create false data dependency */ |
| 244 | subi r10,r10,PTE_FLAGS_OFFSET |
| 245 | lwzx r10,r6,r10 /* Get upper PTE word */ |
| 246 | #else |
| 247 | lwz r10,-PTE_FLAGS_OFFSET(r8) |
| 248 | #endif /* CONFIG_SMP */ |
| 249 | #endif /* CONFIG_PTE_64BIT */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 250 | ori r5,r6,_PAGE_HASHPTE |
| 251 | stwcx. r5,0,r8 |
| 252 | bne- 1b |
| 253 | |
| 254 | bl create_hpte |
| 255 | |
| 256 | 9: |
| 257 | #ifdef CONFIG_SMP |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 258 | addis r6,r7,mmu_hash_lock@ha |
| 259 | addi r6,r6,mmu_hash_lock@l |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 260 | eieio |
| 261 | li r0,0 |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 262 | stw r0,0(r6) /* clear mmu_hash_lock */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 263 | #endif |
| 264 | |
| 265 | /* reenable interrupts and DR */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 266 | mtmsr r9 |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 267 | SYNC_601 |
| 268 | isync |
| 269 | |
| 270 | lwz r0,4(r1) |
| 271 | mtlr r0 |
| 272 | blr |
| 273 | |
| 274 | /* |
| 275 | * This routine adds a hardware PTE to the hash table. |
| 276 | * It is designed to be called with the MMU either on or off. |
| 277 | * r3 contains the VSID, r4 contains the virtual address, |
| 278 | * r5 contains the linux PTE, r6 contains the old value of the |
| 279 | * linux PTE (before setting _PAGE_HASHPTE) and r7 contains the |
| 280 | * offset to be added to addresses (0 if the MMU is on, |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 281 | * -KERNELBASE if it is off). r10 contains the upper half of |
| 282 | * the PTE if CONFIG_PTE_64BIT. |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 283 | * On SMP, the caller should have the mmu_hash_lock held. |
| 284 | * We assume that the caller has (or will) set the _PAGE_HASHPTE |
| 285 | * bit in the linux PTE in memory. The value passed in r6 should |
| 286 | * be the old linux PTE value; if it doesn't have _PAGE_HASHPTE set |
| 287 | * this routine will skip the search for an existing HPTE. |
| 288 | * This procedure modifies r0, r3 - r6, r8, cr0. |
| 289 | * -- paulus. |
| 290 | * |
| 291 | * For speed, 4 of the instructions get patched once the size and |
| 292 | * physical address of the hash table are known. These definitions |
| 293 | * of Hash_base and Hash_bits below are just an example. |
| 294 | */ |
| 295 | Hash_base = 0xc0180000 |
| 296 | Hash_bits = 12 /* e.g. 256kB hash table */ |
| 297 | Hash_msk = (((1 << Hash_bits) - 1) * 64) |
| 298 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 299 | /* defines for the PTE format for 32-bit PPCs */ |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 300 | #define HPTE_SIZE 8 |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 301 | #define PTEG_SIZE 64 |
| 302 | #define LG_PTEG_SIZE 6 |
| 303 | #define LDPTEu lwzu |
Benjamin Herrenschmidt | ee4f2ea | 2007-04-12 15:30:22 +1000 | [diff] [blame] | 304 | #define LDPTE lwz |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 305 | #define STPTE stw |
| 306 | #define CMPPTE cmpw |
| 307 | #define PTE_H 0x40 |
| 308 | #define PTE_V 0x80000000 |
| 309 | #define TST_V(r) rlwinm. r,r,0,0,0 |
| 310 | #define SET_V(r) oris r,r,PTE_V@h |
| 311 | #define CLR_V(r,t) rlwinm r,r,0,1,31 |
| 312 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 313 | #define HASH_LEFT 31-(LG_PTEG_SIZE+Hash_bits-1) |
| 314 | #define HASH_RIGHT 31-LG_PTEG_SIZE |
| 315 | |
| 316 | _GLOBAL(create_hpte) |
| 317 | /* Convert linux-style PTE (r5) to low word of PPC-style PTE (r8) */ |
| 318 | rlwinm r8,r5,32-10,31,31 /* _PAGE_RW -> PP lsb */ |
| 319 | rlwinm r0,r5,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */ |
| 320 | and r8,r8,r0 /* writable if _RW & _DIRTY */ |
| 321 | rlwimi r5,r5,32-1,30,30 /* _PAGE_USER -> PP msb */ |
| 322 | rlwimi r5,r5,32-2,31,31 /* _PAGE_USER -> PP lsb */ |
Kumar Gala | f99fb8a | 2009-02-10 10:57:46 +0000 | [diff] [blame^] | 323 | ori r8,r8,0xe04 /* clear out reserved bits */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 324 | andc r8,r5,r8 /* PP = user? (rw&dirty? 2: 3): 0 */ |
| 325 | BEGIN_FTR_SECTION |
Benjamin Herrenschmidt | 64b3d0e | 2008-12-18 19:13:51 +0000 | [diff] [blame] | 326 | rlwinm r8,r8,0,~_PAGE_COHERENT /* clear M (coherence not required) */ |
| 327 | END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT) |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 328 | #ifdef CONFIG_PTE_64BIT |
| 329 | /* Put the XPN bits into the PTE */ |
| 330 | rlwimi r8,r10,8,20,22 |
| 331 | rlwimi r8,r10,2,29,29 |
| 332 | #endif |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 333 | |
| 334 | /* Construct the high word of the PPC-style PTE (r5) */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 335 | rlwinm r5,r3,7,1,24 /* put VSID in 0x7fffff80 bits */ |
| 336 | rlwimi r5,r4,10,26,31 /* put in API (abbrev page index) */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 337 | SET_V(r5) /* set V (valid) bit */ |
| 338 | |
| 339 | /* Get the address of the primary PTE group in the hash table (r3) */ |
| 340 | _GLOBAL(hash_page_patch_A) |
| 341 | addis r0,r7,Hash_base@h /* base address of hash table */ |
| 342 | rlwimi r0,r3,LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* VSID -> hash */ |
| 343 | rlwinm r3,r4,20+LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* PI -> hash */ |
| 344 | xor r3,r3,r0 /* make primary hash */ |
| 345 | li r0,8 /* PTEs/group */ |
| 346 | |
| 347 | /* |
| 348 | * Test the _PAGE_HASHPTE bit in the old linux PTE, and skip the search |
| 349 | * if it is clear, meaning that the HPTE isn't there already... |
| 350 | */ |
| 351 | andi. r6,r6,_PAGE_HASHPTE |
| 352 | beq+ 10f /* no PTE: go look for an empty slot */ |
| 353 | tlbie r4 |
| 354 | |
| 355 | addis r4,r7,htab_hash_searches@ha |
| 356 | lwz r6,htab_hash_searches@l(r4) |
| 357 | addi r6,r6,1 /* count how many searches we do */ |
| 358 | stw r6,htab_hash_searches@l(r4) |
| 359 | |
| 360 | /* Search the primary PTEG for a PTE whose 1st (d)word matches r5 */ |
| 361 | mtctr r0 |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 362 | addi r4,r3,-HPTE_SIZE |
| 363 | 1: LDPTEu r6,HPTE_SIZE(r4) /* get next PTE */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 364 | CMPPTE 0,r6,r5 |
| 365 | bdnzf 2,1b /* loop while ctr != 0 && !cr0.eq */ |
| 366 | beq+ found_slot |
| 367 | |
| 368 | /* Search the secondary PTEG for a matching PTE */ |
| 369 | ori r5,r5,PTE_H /* set H (secondary hash) bit */ |
| 370 | _GLOBAL(hash_page_patch_B) |
| 371 | xoris r4,r3,Hash_msk>>16 /* compute secondary hash */ |
| 372 | xori r4,r4,(-PTEG_SIZE & 0xffff) |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 373 | addi r4,r4,-HPTE_SIZE |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 374 | mtctr r0 |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 375 | 2: LDPTEu r6,HPTE_SIZE(r4) |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 376 | CMPPTE 0,r6,r5 |
| 377 | bdnzf 2,2b |
| 378 | beq+ found_slot |
| 379 | xori r5,r5,PTE_H /* clear H bit again */ |
| 380 | |
| 381 | /* Search the primary PTEG for an empty slot */ |
| 382 | 10: mtctr r0 |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 383 | addi r4,r3,-HPTE_SIZE /* search primary PTEG */ |
| 384 | 1: LDPTEu r6,HPTE_SIZE(r4) /* get next PTE */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 385 | TST_V(r6) /* test valid bit */ |
| 386 | bdnzf 2,1b /* loop while ctr != 0 && !cr0.eq */ |
| 387 | beq+ found_empty |
| 388 | |
| 389 | /* update counter of times that the primary PTEG is full */ |
| 390 | addis r4,r7,primary_pteg_full@ha |
| 391 | lwz r6,primary_pteg_full@l(r4) |
| 392 | addi r6,r6,1 |
| 393 | stw r6,primary_pteg_full@l(r4) |
| 394 | |
| 395 | /* Search the secondary PTEG for an empty slot */ |
| 396 | ori r5,r5,PTE_H /* set H (secondary hash) bit */ |
| 397 | _GLOBAL(hash_page_patch_C) |
| 398 | xoris r4,r3,Hash_msk>>16 /* compute secondary hash */ |
| 399 | xori r4,r4,(-PTEG_SIZE & 0xffff) |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 400 | addi r4,r4,-HPTE_SIZE |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 401 | mtctr r0 |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 402 | 2: LDPTEu r6,HPTE_SIZE(r4) |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 403 | TST_V(r6) |
| 404 | bdnzf 2,2b |
| 405 | beq+ found_empty |
| 406 | xori r5,r5,PTE_H /* clear H bit again */ |
| 407 | |
| 408 | /* |
| 409 | * Choose an arbitrary slot in the primary PTEG to overwrite. |
| 410 | * Since both the primary and secondary PTEGs are full, and we |
| 411 | * have no information that the PTEs in the primary PTEG are |
| 412 | * more important or useful than those in the secondary PTEG, |
| 413 | * and we know there is a definite (although small) speed |
| 414 | * advantage to putting the PTE in the primary PTEG, we always |
| 415 | * put the PTE in the primary PTEG. |
Benjamin Herrenschmidt | ee4f2ea | 2007-04-12 15:30:22 +1000 | [diff] [blame] | 416 | * |
| 417 | * In addition, we skip any slot that is mapping kernel text in |
| 418 | * order to avoid a deadlock when not using BAT mappings if |
| 419 | * trying to hash in the kernel hash code itself after it has |
| 420 | * already taken the hash table lock. This works in conjunction |
| 421 | * with pre-faulting of the kernel text. |
| 422 | * |
| 423 | * If the hash table bucket is full of kernel text entries, we'll |
| 424 | * lockup here but that shouldn't happen |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 425 | */ |
Benjamin Herrenschmidt | ee4f2ea | 2007-04-12 15:30:22 +1000 | [diff] [blame] | 426 | |
| 427 | 1: addis r4,r7,next_slot@ha /* get next evict slot */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 428 | lwz r6,next_slot@l(r4) |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 429 | addi r6,r6,HPTE_SIZE /* search for candidate */ |
| 430 | andi. r6,r6,7*HPTE_SIZE |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 431 | stw r6,next_slot@l(r4) |
| 432 | add r4,r3,r6 |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 433 | LDPTE r0,HPTE_SIZE/2(r4) /* get PTE second word */ |
Benjamin Herrenschmidt | ee4f2ea | 2007-04-12 15:30:22 +1000 | [diff] [blame] | 434 | clrrwi r0,r0,12 |
| 435 | lis r6,etext@h |
| 436 | ori r6,r6,etext@l /* get etext */ |
| 437 | tophys(r6,r6) |
| 438 | cmpl cr0,r0,r6 /* compare and try again */ |
| 439 | blt 1b |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 440 | |
| 441 | #ifndef CONFIG_SMP |
| 442 | /* Store PTE in PTEG */ |
| 443 | found_empty: |
| 444 | STPTE r5,0(r4) |
| 445 | found_slot: |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 446 | STPTE r8,HPTE_SIZE/2(r4) |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 447 | |
| 448 | #else /* CONFIG_SMP */ |
| 449 | /* |
| 450 | * Between the tlbie above and updating the hash table entry below, |
| 451 | * another CPU could read the hash table entry and put it in its TLB. |
| 452 | * There are 3 cases: |
| 453 | * 1. using an empty slot |
| 454 | * 2. updating an earlier entry to change permissions (i.e. enable write) |
| 455 | * 3. taking over the PTE for an unrelated address |
| 456 | * |
| 457 | * In each case it doesn't really matter if the other CPUs have the old |
| 458 | * PTE in their TLB. So we don't need to bother with another tlbie here, |
| 459 | * which is convenient as we've overwritten the register that had the |
| 460 | * address. :-) The tlbie above is mainly to make sure that this CPU comes |
| 461 | * and gets the new PTE from the hash table. |
| 462 | * |
| 463 | * We do however have to make sure that the PTE is never in an invalid |
| 464 | * state with the V bit set. |
| 465 | */ |
| 466 | found_empty: |
| 467 | found_slot: |
| 468 | CLR_V(r5,r0) /* clear V (valid) bit in PTE */ |
| 469 | STPTE r5,0(r4) |
| 470 | sync |
| 471 | TLBSYNC |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 472 | STPTE r8,HPTE_SIZE/2(r4) /* put in correct RPN, WIMG, PP bits */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 473 | sync |
| 474 | SET_V(r5) |
| 475 | STPTE r5,0(r4) /* finally set V bit in PTE */ |
| 476 | #endif /* CONFIG_SMP */ |
| 477 | |
| 478 | sync /* make sure pte updates get to memory */ |
| 479 | blr |
| 480 | |
Kumar Gala | 991eb43 | 2007-05-14 17:11:58 -0500 | [diff] [blame] | 481 | .section .bss |
| 482 | .align 2 |
| 483 | next_slot: |
| 484 | .space 4 |
| 485 | primary_pteg_full: |
| 486 | .space 4 |
| 487 | htab_hash_searches: |
| 488 | .space 4 |
| 489 | .previous |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 490 | |
| 491 | /* |
| 492 | * Flush the entry for a particular page from the hash table. |
| 493 | * |
| 494 | * flush_hash_pages(unsigned context, unsigned long va, unsigned long pmdval, |
| 495 | * int count) |
| 496 | * |
| 497 | * We assume that there is a hash table in use (Hash != 0). |
| 498 | */ |
| 499 | _GLOBAL(flush_hash_pages) |
| 500 | tophys(r7,0) |
| 501 | |
| 502 | /* |
| 503 | * We disable interrupts here, even on UP, because we want |
| 504 | * the _PAGE_HASHPTE bit to be a reliable indication of |
| 505 | * whether the HPTE exists (or at least whether one did once). |
| 506 | * We also turn off the MMU for data accesses so that we |
| 507 | * we can't take a hash table miss (assuming the code is |
| 508 | * covered by a BAT). -- paulus |
| 509 | */ |
| 510 | mfmsr r10 |
| 511 | SYNC |
| 512 | rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */ |
| 513 | rlwinm r0,r0,0,28,26 /* clear MSR_DR */ |
| 514 | mtmsr r0 |
| 515 | SYNC_601 |
| 516 | isync |
| 517 | |
| 518 | /* First find a PTE in the range that has _PAGE_HASHPTE set */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 519 | #ifndef CONFIG_PTE_64BIT |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 520 | rlwimi r5,r4,22,20,29 |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 521 | #else |
| 522 | rlwimi r5,r4,23,20,28 |
| 523 | #endif |
| 524 | 1: lwz r0,PTE_FLAGS_OFFSET(r5) |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 525 | cmpwi cr1,r6,1 |
| 526 | andi. r0,r0,_PAGE_HASHPTE |
| 527 | bne 2f |
| 528 | ble cr1,19f |
| 529 | addi r4,r4,0x1000 |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 530 | addi r5,r5,PTE_SIZE |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 531 | addi r6,r6,-1 |
| 532 | b 1b |
| 533 | |
| 534 | /* Convert context and va to VSID */ |
| 535 | 2: mulli r3,r3,897*16 /* multiply context by context skew */ |
| 536 | rlwinm r0,r4,4,28,31 /* get ESID (top 4 bits of va) */ |
| 537 | mulli r0,r0,0x111 /* multiply by ESID skew */ |
| 538 | add r3,r3,r0 /* note code below trims to 24 bits */ |
| 539 | |
| 540 | /* Construct the high word of the PPC-style PTE (r11) */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 541 | rlwinm r11,r3,7,1,24 /* put VSID in 0x7fffff80 bits */ |
| 542 | rlwimi r11,r4,10,26,31 /* put in API (abbrev page index) */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 543 | SET_V(r11) /* set V (valid) bit */ |
| 544 | |
| 545 | #ifdef CONFIG_SMP |
| 546 | addis r9,r7,mmu_hash_lock@ha |
| 547 | addi r9,r9,mmu_hash_lock@l |
Kumar Gala | f608600 | 2008-04-24 06:29:36 +1000 | [diff] [blame] | 548 | rlwinm r8,r1,0,0,(31-THREAD_SHIFT) |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 549 | add r8,r8,r7 |
| 550 | lwz r8,TI_CPU(r8) |
| 551 | oris r8,r8,9 |
| 552 | 10: lwarx r0,0,r9 |
| 553 | cmpi 0,r0,0 |
| 554 | bne- 11f |
| 555 | stwcx. r8,0,r9 |
| 556 | beq+ 12f |
| 557 | 11: lwz r0,0(r9) |
| 558 | cmpi 0,r0,0 |
| 559 | beq 10b |
| 560 | b 11b |
| 561 | 12: isync |
| 562 | #endif |
| 563 | |
| 564 | /* |
| 565 | * Check the _PAGE_HASHPTE bit in the linux PTE. If it is |
| 566 | * already clear, we're done (for this pte). If not, |
| 567 | * clear it (atomically) and proceed. -- paulus. |
| 568 | */ |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 569 | #if (PTE_FLAGS_OFFSET != 0) |
| 570 | addi r5,r5,PTE_FLAGS_OFFSET |
| 571 | #endif |
| 572 | 33: lwarx r8,0,r5 /* fetch the pte flags word */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 573 | andi. r0,r8,_PAGE_HASHPTE |
| 574 | beq 8f /* done if HASHPTE is already clear */ |
| 575 | rlwinm r8,r8,0,31,29 /* clear HASHPTE bit */ |
| 576 | stwcx. r8,0,r5 /* update the pte */ |
| 577 | bne- 33b |
| 578 | |
| 579 | /* Get the address of the primary PTE group in the hash table (r3) */ |
| 580 | _GLOBAL(flush_hash_patch_A) |
| 581 | addis r8,r7,Hash_base@h /* base address of hash table */ |
| 582 | rlwimi r8,r3,LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* VSID -> hash */ |
| 583 | rlwinm r0,r4,20+LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* PI -> hash */ |
| 584 | xor r8,r0,r8 /* make primary hash */ |
| 585 | |
| 586 | /* Search the primary PTEG for a PTE whose 1st (d)word matches r5 */ |
| 587 | li r0,8 /* PTEs/group */ |
| 588 | mtctr r0 |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 589 | addi r12,r8,-HPTE_SIZE |
| 590 | 1: LDPTEu r0,HPTE_SIZE(r12) /* get next PTE */ |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 591 | CMPPTE 0,r0,r11 |
| 592 | bdnzf 2,1b /* loop while ctr != 0 && !cr0.eq */ |
| 593 | beq+ 3f |
| 594 | |
| 595 | /* Search the secondary PTEG for a matching PTE */ |
| 596 | ori r11,r11,PTE_H /* set H (secondary hash) bit */ |
| 597 | li r0,8 /* PTEs/group */ |
| 598 | _GLOBAL(flush_hash_patch_B) |
| 599 | xoris r12,r8,Hash_msk>>16 /* compute secondary hash */ |
| 600 | xori r12,r12,(-PTEG_SIZE & 0xffff) |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 601 | addi r12,r12,-HPTE_SIZE |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 602 | mtctr r0 |
Becky Bruce | aaf4a9b0 | 2008-09-04 01:37:53 +1000 | [diff] [blame] | 603 | 2: LDPTEu r0,HPTE_SIZE(r12) |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 604 | CMPPTE 0,r0,r11 |
| 605 | bdnzf 2,2b |
| 606 | xori r11,r11,PTE_H /* clear H again */ |
| 607 | bne- 4f /* should rarely fail to find it */ |
| 608 | |
| 609 | 3: li r0,0 |
| 610 | STPTE r0,0(r12) /* invalidate entry */ |
| 611 | 4: sync |
| 612 | tlbie r4 /* in hw tlb too */ |
| 613 | sync |
| 614 | |
| 615 | 8: ble cr1,9f /* if all ptes checked */ |
| 616 | 81: addi r6,r6,-1 |
Becky Bruce | 4ee7084 | 2008-09-24 11:01:24 -0500 | [diff] [blame] | 617 | addi r5,r5,PTE_SIZE |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 618 | addi r4,r4,0x1000 |
| 619 | lwz r0,0(r5) /* check next pte */ |
| 620 | cmpwi cr1,r6,1 |
| 621 | andi. r0,r0,_PAGE_HASHPTE |
| 622 | bne 33b |
| 623 | bgt cr1,81b |
| 624 | |
| 625 | 9: |
| 626 | #ifdef CONFIG_SMP |
| 627 | TLBSYNC |
| 628 | li r0,0 |
| 629 | stw r0,0(r9) /* clear mmu_hash_lock */ |
| 630 | #endif |
| 631 | |
| 632 | 19: mtmsr r10 |
| 633 | SYNC_601 |
| 634 | isync |
| 635 | blr |
Benjamin Herrenschmidt | 2a4aca11 | 2008-12-18 19:13:42 +0000 | [diff] [blame] | 636 | |
| 637 | /* |
| 638 | * Flush an entry from the TLB |
| 639 | */ |
| 640 | _GLOBAL(_tlbie) |
| 641 | #ifdef CONFIG_SMP |
| 642 | rlwinm r8,r1,0,0,(31-THREAD_SHIFT) |
| 643 | lwz r8,TI_CPU(r8) |
| 644 | oris r8,r8,11 |
| 645 | mfmsr r10 |
| 646 | SYNC |
| 647 | rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */ |
| 648 | rlwinm r0,r0,0,28,26 /* clear DR */ |
| 649 | mtmsr r0 |
| 650 | SYNC_601 |
| 651 | isync |
| 652 | lis r9,mmu_hash_lock@h |
| 653 | ori r9,r9,mmu_hash_lock@l |
| 654 | tophys(r9,r9) |
| 655 | 10: lwarx r7,0,r9 |
| 656 | cmpwi 0,r7,0 |
| 657 | bne- 10b |
| 658 | stwcx. r8,0,r9 |
| 659 | bne- 10b |
| 660 | eieio |
| 661 | tlbie r3 |
| 662 | sync |
| 663 | TLBSYNC |
| 664 | li r0,0 |
| 665 | stw r0,0(r9) /* clear mmu_hash_lock */ |
| 666 | mtmsr r10 |
| 667 | SYNC_601 |
| 668 | isync |
| 669 | #else /* CONFIG_SMP */ |
| 670 | tlbie r3 |
| 671 | sync |
| 672 | #endif /* CONFIG_SMP */ |
| 673 | blr |
| 674 | |
| 675 | /* |
| 676 | * Flush the entire TLB. 603/603e only |
| 677 | */ |
| 678 | _GLOBAL(_tlbia) |
| 679 | #if defined(CONFIG_SMP) |
| 680 | rlwinm r8,r1,0,0,(31-THREAD_SHIFT) |
| 681 | lwz r8,TI_CPU(r8) |
| 682 | oris r8,r8,10 |
| 683 | mfmsr r10 |
| 684 | SYNC |
| 685 | rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */ |
| 686 | rlwinm r0,r0,0,28,26 /* clear DR */ |
| 687 | mtmsr r0 |
| 688 | SYNC_601 |
| 689 | isync |
| 690 | lis r9,mmu_hash_lock@h |
| 691 | ori r9,r9,mmu_hash_lock@l |
| 692 | tophys(r9,r9) |
| 693 | 10: lwarx r7,0,r9 |
| 694 | cmpwi 0,r7,0 |
| 695 | bne- 10b |
| 696 | stwcx. r8,0,r9 |
| 697 | bne- 10b |
| 698 | sync |
| 699 | tlbia |
| 700 | sync |
| 701 | TLBSYNC |
| 702 | li r0,0 |
| 703 | stw r0,0(r9) /* clear mmu_hash_lock */ |
| 704 | mtmsr r10 |
| 705 | SYNC_601 |
| 706 | isync |
| 707 | #else /* CONFIG_SMP */ |
| 708 | sync |
| 709 | tlbia |
| 710 | sync |
| 711 | #endif /* CONFIG_SMP */ |
Benjamin Herrenschmidt | a149535 | 2008-12-21 02:54:25 -0700 | [diff] [blame] | 712 | blr |