arch/powerpc/platforms/pseries/lpar.c

   1 /*
   2  * pSeries_lpar.c
   3  * Copyright (C) 2001 Todd Inglett, IBM Corporation
   4  *
   5  * pSeries LPAR support.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20  */
  21
  22 /* Enables debugging of low-level hash table routines - careful! */
  23 #undef DEBUG
  24
  25 #include <linux/kernel.h>
  26 #include <linux/dma-mapping.h>
  27 #include <linux/console.h>
  28 #include <asm/processor.h>
  29 #include <asm/mmu.h>
  30 #include <asm/page.h>
  31 #include <asm/pgtable.h>
  32 #include <asm/machdep.h>
  33 #include <asm/abs_addr.h>
  34 #include <asm/mmu_context.h>
  35 #include <asm/iommu.h>
  36 #include <asm/tlbflush.h>
  37 #include <asm/tlb.h>
  38 #include <asm/prom.h>
  39 #include <asm/cputable.h>
  40 #include <asm/udbg.h>
  41 #include <asm/smp.h>
  42
  43 #include "plpar_wrappers.h"
  44 #include "pseries.h"
  45
  46
  47 /* in hvCall.S */
  48 EXPORT_SYMBOL(plpar_hcall);
  49 EXPORT_SYMBOL(plpar_hcall9);
  50 EXPORT_SYMBOL(plpar_hcall_norets);
  51
  52 extern void pSeries_find_serial_port(void);
  53
  54
  55 static int vtermno;     /* virtual terminal# for udbg  */
  56
  57 #define __ALIGNED__ __attribute__((__aligned__(sizeof(long))))
  58 static void udbg_hvsi_putc(char c)
  59 {
  60         /* packet's seqno isn't used anyways */
  61         uint8_t packet[] __ALIGNED__ = { 0xff, 5, 0, 0, c };
  62         int rc;
  63
  64         if (c == '\n')
  65                 udbg_hvsi_putc('\r');
  66
  67         do {
  68                 rc = plpar_put_term_char(vtermno, sizeof(packet), packet);
  69         } while (rc == H_BUSY);
  70 }
  71
  72 static long hvsi_udbg_buf_len;
  73 static uint8_t hvsi_udbg_buf[256];
  74
  75 static int udbg_hvsi_getc_poll(void)
  76 {
  77         unsigned char ch;
  78         int rc, i;
  79
  80         if (hvsi_udbg_buf_len == 0) {
  81                 rc = plpar_get_term_char(vtermno, &hvsi_udbg_buf_len, hvsi_udbg_buf);
  82                 if (rc != H_SUCCESS || hvsi_udbg_buf[0] != 0xff) {
  83                         /* bad read or non-data packet */
  84                         hvsi_udbg_buf_len = 0;
  85                 } else {
  86                         /* remove the packet header */
  87                         for (i = 4; i < hvsi_udbg_buf_len; i++)
  88                                 hvsi_udbg_buf[i-4] = hvsi_udbg_buf[i];
  89                         hvsi_udbg_buf_len -= 4;
  90                 }
  91         }
  92
  93         if (hvsi_udbg_buf_len <= 0 || hvsi_udbg_buf_len > 256) {
  94                 /* no data ready */
  95                 hvsi_udbg_buf_len = 0;
  96                 return -1;
  97         }
  98
  99         ch = hvsi_udbg_buf[0];
 100         /* shift remaining data down */
 101         for (i = 1; i < hvsi_udbg_buf_len; i++) {
 102                 hvsi_udbg_buf[i-1] = hvsi_udbg_buf[i];
 103         }
 104         hvsi_udbg_buf_len--;
 105
 106         return ch;
 107 }
 108
 109 static int udbg_hvsi_getc(void)
 110 {
 111         int ch;
 112         for (;;) {
 113                 ch = udbg_hvsi_getc_poll();
 114                 if (ch == -1) {
 115                         /* This shouldn't be needed...but... */
 116                         volatile unsigned long delay;
 117                         for (delay=0; delay < 2000000; delay++)
 118                                 ;
 119                 } else {
 120                         return ch;
 121                 }
 122         }
 123 }
 124
 125 static void udbg_putcLP(char c)
 126 {
 127         char buf[16];
 128         unsigned long rc;
 129
 130         if (c == '\n')
 131                 udbg_putcLP('\r');
 132
 133         buf[0] = c;
 134         do {
 135                 rc = plpar_put_term_char(vtermno, 1, buf);
 136         } while(rc == H_BUSY);
 137 }
 138
 139 /* Buffered chars getc */
 140 static long inbuflen;
 141 static long inbuf[2];   /* must be 2 longs */
 142
 143 static int udbg_getc_pollLP(void)
 144 {
 145         /* The interface is tricky because it may return up to 16 chars.
 146          * We save them statically for future calls to udbg_getc().
 147          */
 148         char ch, *buf = (char *)inbuf;
 149         int i;
 150         long rc;
 151         if (inbuflen == 0) {
 152                 /* get some more chars. */
 153                 inbuflen = 0;
 154                 rc = plpar_get_term_char(vtermno, &inbuflen, buf);
 155                 if (rc != H_SUCCESS)
 156                         inbuflen = 0;   /* otherwise inbuflen is garbage */
 157         }
 158         if (inbuflen <= 0 || inbuflen > 16) {
 159                 /* Catch error case as well as other oddities (corruption) */
 160                 inbuflen = 0;
 161                 return -1;
 162         }
 163         ch = buf[0];
 164         for (i = 1; i < inbuflen; i++)  /* shuffle them down. */
 165                 buf[i-1] = buf[i];
 166         inbuflen--;
 167         return ch;
 168 }
 169
 170 static int udbg_getcLP(void)
 171 {
 172         int ch;
 173         for (;;) {
 174                 ch = udbg_getc_pollLP();
 175                 if (ch == -1) {
 176                         /* This shouldn't be needed...but... */
 177                         volatile unsigned long delay;
 178                         for (delay=0; delay < 2000000; delay++)
 179                                 ;
 180                 } else {
 181                         return ch;
 182                 }
 183         }
 184 }
 185
 186 /* call this from early_init() for a working debug console on
 187  * vterm capable LPAR machines
 188  */
 189 void __init udbg_init_debug_lpar(void)
 190 {
 191         vtermno = 0;
 192         udbg_putc = udbg_putcLP;
 193         udbg_getc = udbg_getcLP;
 194         udbg_getc_poll = udbg_getc_pollLP;
 195
 196         register_early_udbg_console();
 197 }
 198
 199 /* returns 0 if couldn't find or use /chosen/stdout as console */
 200 void __init find_udbg_vterm(void)
 201 {
 202         struct device_node *stdout_node;
 203         const u32 *termno;
 204         const char *name;
 205
 206         /* find the boot console from /chosen/stdout */
 207         if (!of_chosen)
 208                 return;
 209         name = of_get_property(of_chosen, "linux,stdout-path", NULL);
 210         if (name == NULL)
 211                 return;
 212         stdout_node = of_find_node_by_path(name);
 213         if (!stdout_node)
 214                 return;
 215         name = of_get_property(stdout_node, "name", NULL);
 216         if (!name) {
 217                 printk(KERN_WARNING "stdout node missing 'name' property!\n");
 218                 goto out;
 219         }
 220
 221         /* Check if it's a virtual terminal */
 222         if (strncmp(name, "vty", 3) != 0)
 223                 goto out;
 224         termno = of_get_property(stdout_node, "reg", NULL);
 225         if (termno == NULL)
 226                 goto out;
 227         vtermno = termno[0];
 228
 229         if (of_device_is_compatible(stdout_node, "hvterm1")) {
 230                 udbg_putc = udbg_putcLP;
 231                 udbg_getc = udbg_getcLP;
 232                 udbg_getc_poll = udbg_getc_pollLP;
 233                 add_preferred_console("hvc", termno[0] & 0xff, NULL);
 234         } else if (of_device_is_compatible(stdout_node, "hvterm-protocol")) {
 235                 vtermno = termno[0];
 236                 udbg_putc = udbg_hvsi_putc;
 237                 udbg_getc = udbg_hvsi_getc;
 238                 udbg_getc_poll = udbg_hvsi_getc_poll;
 239                 add_preferred_console("hvsi", termno[0] & 0xff, NULL);
 240         }
 241 out:
 242         of_node_put(stdout_node);
 243 }
 244
 245 void vpa_init(int cpu)
 246 {
 247         int hwcpu = get_hard_smp_processor_id(cpu);
 248         unsigned long addr;
 249         long ret;
 250
 251         if (cpu_has_feature(CPU_FTR_ALTIVEC))
 252                 lppaca[cpu].vmxregs_in_use = 1;
 253
 254         addr = __pa(&lppaca[cpu]);
 255         ret = register_vpa(hwcpu, addr);
 256
 257         if (ret) {
 258                 printk(KERN_ERR "WARNING: vpa_init: VPA registration for "
 259                                 "cpu %d (hw %d) of area %lx returns %ld\n",
 260                                 cpu, hwcpu, addr, ret);
 261                 return;
 262         }
 263         /*
 264          * PAPR says this feature is SLB-Buffer but firmware never
 265          * reports that.  All SPLPAR support SLB shadow buffer.
 266          */
 267         addr = __pa(&slb_shadow[cpu]);
 268         if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
 269                 ret = register_slb_shadow(hwcpu, addr);
 270                 if (ret)
 271                         printk(KERN_ERR
 272                                "WARNING: vpa_init: SLB shadow buffer "
 273                                "registration for cpu %d (hw %d) of area %lx "
 274                                "returns %ld\n", cpu, hwcpu, addr, ret);
 275         }
 276 }
 277
 278 static long pSeries_lpar_hpte_insert(unsigned long hpte_group,
 279                               unsigned long va, unsigned long pa,
 280                               unsigned long rflags, unsigned long vflags,
 281                               int psize, int ssize)
 282 {
 283         unsigned long lpar_rc;
 284         unsigned long flags;
 285         unsigned long slot;
 286         unsigned long hpte_v, hpte_r;
 287
 288         if (!(vflags & HPTE_V_BOLTED))
 289                 pr_devel("hpte_insert(group=%lx, va=%016lx, pa=%016lx, "
 290                          "rflags=%lx, vflags=%lx, psize=%d)\n",
 291                          hpte_group, va, pa, rflags, vflags, psize);
 292
 293         hpte_v = hpte_encode_v(va, psize, ssize) | vflags | HPTE_V_VALID;
 294         hpte_r = hpte_encode_r(pa, psize) | rflags;
 295
 296         if (!(vflags & HPTE_V_BOLTED))
 297                 pr_devel(" hpte_v=%016lx, hpte_r=%016lx\n", hpte_v, hpte_r);
 298
 299         /* Now fill in the actual HPTE */
 300         /* Set CEC cookie to 0         */
 301         /* Zero page = 0               */
 302         /* I-cache Invalidate = 0      */
 303         /* I-cache synchronize = 0     */
 304         /* Exact = 0                   */
 305         flags = 0;
 306
 307         /* Make pHyp happy */
 308         if ((rflags & _PAGE_NO_CACHE) & !(rflags & _PAGE_WRITETHRU))
 309                 hpte_r &= ~_PAGE_COHERENT;
 310
 311         lpar_rc = plpar_pte_enter(flags, hpte_group, hpte_v, hpte_r, &slot);
 312         if (unlikely(lpar_rc == H_PTEG_FULL)) {
 313                 if (!(vflags & HPTE_V_BOLTED))
 314                         pr_devel(" full\n");
 315                 return -1;
 316         }
 317
 318         /*
 319          * Since we try and ioremap PHBs we don't own, the pte insert
 320          * will fail. However we must catch the failure in hash_page
 321          * or we will loop forever, so return -2 in this case.
 322          */
 323         if (unlikely(lpar_rc != H_SUCCESS)) {
 324                 if (!(vflags & HPTE_V_BOLTED))
 325                         pr_devel(" lpar err %lu\n", lpar_rc);
 326                 return -2;
 327         }
 328         if (!(vflags & HPTE_V_BOLTED))
 329                 pr_devel(" -> slot: %lu\n", slot & 7);
 330
 331         /* Because of iSeries, we have to pass down the secondary
 332          * bucket bit here as well
 333          */
 334         return (slot & 7) | (!!(vflags & HPTE_V_SECONDARY) << 3);
 335 }
 336
 337 static DEFINE_SPINLOCK(pSeries_lpar_tlbie_lock);
 338
 339 static long pSeries_lpar_hpte_remove(unsigned long hpte_group)
 340 {
 341         unsigned long slot_offset;
 342         unsigned long lpar_rc;
 343         int i;
 344         unsigned long dummy1, dummy2;
 345
 346         /* pick a random slot to start at */
 347         slot_offset = mftb() & 0x7;
 348
 349         for (i = 0; i < HPTES_PER_GROUP; i++) {
 350
 351                 /* don't remove a bolted entry */
 352                 lpar_rc = plpar_pte_remove(H_ANDCOND, hpte_group + slot_offset,
 353                                            (0x1UL << 4), &dummy1, &dummy2);
 354                 if (lpar_rc == H_SUCCESS)
 355                         return i;
 356                 BUG_ON(lpar_rc != H_NOT_FOUND);
 357
 358                 slot_offset++;
 359                 slot_offset &= 0x7;
 360         }
 361
 362         return -1;
 363 }
 364
 365 static void pSeries_lpar_hptab_clear(void)
 366 {
 367         unsigned long size_bytes = 1UL << ppc64_pft_size;
 368         unsigned long hpte_count = size_bytes >> 4;
 369         unsigned long dummy1, dummy2, dword0;
 370         long lpar_rc;
 371         int i;
 372
 373         /* TODO: Use bulk call */
 374         for (i = 0; i < hpte_count; i++) {
 375                 /* dont remove HPTEs with VRMA mappings */
 376                 lpar_rc = plpar_pte_remove_raw(H_ANDCOND, i, HPTE_V_1TB_SEG,
 377                                                 &dummy1, &dummy2);
 378                 if (lpar_rc == H_NOT_FOUND) {
 379                         lpar_rc = plpar_pte_read_raw(0, i, &dword0, &dummy1);
 380                         if (!lpar_rc && ((dword0 & HPTE_V_VRMA_MASK)
 381                                 != HPTE_V_VRMA_MASK))
 382                                 /* Can be hpte for 1TB Seg. So remove it */
 383                                 plpar_pte_remove_raw(0, i, 0, &dummy1, &dummy2);
 384                 }
 385         }
 386 }
 387
 388 /*
 389  * This computes the AVPN and B fields of the first dword of a HPTE,
 390  * for use when we want to match an existing PTE.  The bottom 7 bits
 391  * of the returned value are zero.
 392  */
 393 static inline unsigned long hpte_encode_avpn(unsigned long va, int psize,
 394                                              int ssize)
 395 {
 396         unsigned long v;
 397
 398         v = (va >> 23) & ~(mmu_psize_defs[psize].avpnm);
 399         v <<= HPTE_V_AVPN_SHIFT;
 400         v |= ((unsigned long) ssize) << HPTE_V_SSIZE_SHIFT;
 401         return v;
 402 }
 403
 404 /*
 405  * NOTE: for updatepp ops we are fortunate that the linux "newpp" bits and
 406  * the low 3 bits of flags happen to line up.  So no transform is needed.
 407  * We can probably optimize here and assume the high bits of newpp are
 408  * already zero.  For now I am paranoid.
 409  */
 410 static long pSeries_lpar_hpte_updatepp(unsigned long slot,
 411                                        unsigned long newpp,
 412                                        unsigned long va,
 413                                        int psize, int ssize, int local)
 414 {
 415         unsigned long lpar_rc;
 416         unsigned long flags = (newpp & 7) | H_AVPN;
 417         unsigned long want_v;
 418
 419         want_v = hpte_encode_avpn(va, psize, ssize);
 420
 421         pr_devel("    update: avpnv=%016lx, hash=%016lx, f=%lx, psize: %d ...",
 422                  want_v, slot, flags, psize);
 423
 424         lpar_rc = plpar_pte_protect(flags, slot, want_v);
 425
 426         if (lpar_rc == H_NOT_FOUND) {
 427                 pr_devel("not found !\n");
 428                 return -1;
 429         }
 430
 431         pr_devel("ok\n");
 432
 433         BUG_ON(lpar_rc != H_SUCCESS);
 434
 435         return 0;
 436 }
 437
 438 static unsigned long pSeries_lpar_hpte_getword0(unsigned long slot)
 439 {
 440         unsigned long dword0;
 441         unsigned long lpar_rc;
 442         unsigned long dummy_word1;
 443         unsigned long flags;
 444
 445         /* Read 1 pte at a time                        */
 446         /* Do not need RPN to logical page translation */
 447         /* No cross CEC PFT access                     */
 448         flags = 0;
 449
 450         lpar_rc = plpar_pte_read(flags, slot, &dword0, &dummy_word1);
 451
 452         BUG_ON(lpar_rc != H_SUCCESS);
 453
 454         return dword0;
 455 }
 456
 457 static long pSeries_lpar_hpte_find(unsigned long va, int psize, int ssize)
 458 {
 459         unsigned long hash;
 460         unsigned long i;
 461         long slot;
 462         unsigned long want_v, hpte_v;
 463
 464         hash = hpt_hash(va, mmu_psize_defs[psize].shift, ssize);
 465         want_v = hpte_encode_avpn(va, psize, ssize);
 466
 467         /* Bolted entries are always in the primary group */
 468         slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
 469         for (i = 0; i < HPTES_PER_GROUP; i++) {
 470                 hpte_v = pSeries_lpar_hpte_getword0(slot);
 471
 472                 if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID))
 473                         /* HPTE matches */
 474                         return slot;
 475                 ++slot;
 476         }
 477
 478         return -1;
 479 }
 480
 481 static void pSeries_lpar_hpte_updateboltedpp(unsigned long newpp,
 482                                              unsigned long ea,
 483                                              int psize, int ssize)
 484 {
 485         unsigned long lpar_rc, slot, vsid, va, flags;
 486
 487         vsid = get_kernel_vsid(ea, ssize);
 488         va = hpt_va(ea, vsid, ssize);
 489
 490         slot = pSeries_lpar_hpte_find(va, psize, ssize);
 491         BUG_ON(slot == -1);
 492
 493         flags = newpp & 7;
 494         lpar_rc = plpar_pte_protect(flags, slot, 0);
 495
 496         BUG_ON(lpar_rc != H_SUCCESS);
 497 }
 498
 499 static void pSeries_lpar_hpte_invalidate(unsigned long slot, unsigned long va,
 500                                          int psize, int ssize, int local)
 501 {
 502         unsigned long want_v;
 503         unsigned long lpar_rc;
 504         unsigned long dummy1, dummy2;
 505
 506         pr_devel("    inval : slot=%lx, va=%016lx, psize: %d, local: %d\n",
 507                  slot, va, psize, local);
 508
 509         want_v = hpte_encode_avpn(va, psize, ssize);
 510         lpar_rc = plpar_pte_remove(H_AVPN, slot, want_v, &dummy1, &dummy2);
 511         if (lpar_rc == H_NOT_FOUND)
 512                 return;
 513
 514         BUG_ON(lpar_rc != H_SUCCESS);
 515 }
 516
 517 static void pSeries_lpar_hpte_removebolted(unsigned long ea,
 518                                            int psize, int ssize)
 519 {
 520         unsigned long slot, vsid, va;
 521
 522         vsid = get_kernel_vsid(ea, ssize);
 523         va = hpt_va(ea, vsid, ssize);
 524
 525         slot = pSeries_lpar_hpte_find(va, psize, ssize);
 526         BUG_ON(slot == -1);
 527
 528         pSeries_lpar_hpte_invalidate(slot, va, psize, ssize, 0);
 529 }
 530
 531 /* Flag bits for H_BULK_REMOVE */
 532 #define HBR_REQUEST     0x4000000000000000UL
 533 #define HBR_RESPONSE    0x8000000000000000UL
 534 #define HBR_END         0xc000000000000000UL
 535 #define HBR_AVPN        0x0200000000000000UL
 536 #define HBR_ANDCOND     0x0100000000000000UL
 537
 538 /*
 539  * Take a spinlock around flushes to avoid bouncing the hypervisor tlbie
 540  * lock.
 541  */
 542 static void pSeries_lpar_flush_hash_range(unsigned long number, int local)
 543 {
 544         unsigned long i, pix, rc;
 545         unsigned long flags = 0;
 546         struct ppc64_tlb_batch *batch = &__get_cpu_var(ppc64_tlb_batch);
 547         int lock_tlbie = !cpu_has_feature(CPU_FTR_LOCKLESS_TLBIE);
 548         unsigned long param[9];
 549         unsigned long va;
 550         unsigned long hash, index, shift, hidx, slot;
 551         real_pte_t pte;
 552         int psize, ssize;
 553
 554         if (lock_tlbie)
 555                 spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
 556
 557         psize = batch->psize;
 558         ssize = batch->ssize;
 559         pix = 0;
 560         for (i = 0; i < number; i++) {
 561                 va = batch->vaddr[i];
 562                 pte = batch->pte[i];
 563                 pte_iterate_hashed_subpages(pte, psize, va, index, shift) {
 564                         hash = hpt_hash(va, shift, ssize);
 565                         hidx = __rpte_to_hidx(pte, index);
 566                         if (hidx & _PTEIDX_SECONDARY)
 567                                 hash = ~hash;
 568                         slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
 569                         slot += hidx & _PTEIDX_GROUP_IX;
 570                         if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
 571                                 pSeries_lpar_hpte_invalidate(slot, va, psize,
 572                                                              ssize, local);
 573                         } else {
 574                                 param[pix] = HBR_REQUEST | HBR_AVPN | slot;
 575                                 param[pix+1] = hpte_encode_avpn(va, psize,
 576                                                                 ssize);
 577                                 pix += 2;
 578                                 if (pix == 8) {
 579                                         rc = plpar_hcall9(H_BULK_REMOVE, param,
 580                                                 param[0], param[1], param[2],
 581                                                 param[3], param[4], param[5],
 582                                                 param[6], param[7]);
 583                                         BUG_ON(rc != H_SUCCESS);
 584                                         pix = 0;
 585                                 }
 586                         }
 587                 } pte_iterate_hashed_end();
 588         }
 589         if (pix) {
 590                 param[pix] = HBR_END;
 591                 rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],
 592                                   param[2], param[3], param[4], param[5],
 593                                   param[6], param[7]);
 594                 BUG_ON(rc != H_SUCCESS);
 595         }
 596
 597         if (lock_tlbie)
 598                 spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
 599 }
 600
 601 void __init hpte_init_lpar(void)
 602 {
 603         ppc_md.hpte_invalidate  = pSeries_lpar_hpte_invalidate;
 604         ppc_md.hpte_updatepp    = pSeries_lpar_hpte_updatepp;
 605         ppc_md.hpte_updateboltedpp = pSeries_lpar_hpte_updateboltedpp;
 606         ppc_md.hpte_insert      = pSeries_lpar_hpte_insert;
 607         ppc_md.hpte_remove      = pSeries_lpar_hpte_remove;
 608         ppc_md.hpte_removebolted = pSeries_lpar_hpte_removebolted;
 609         ppc_md.flush_hash_range = pSeries_lpar_flush_hash_range;
 610         ppc_md.hpte_clear_all   = pSeries_lpar_hptab_clear;
 611 }
 612
 613 #ifdef CONFIG_PPC_SMLPAR
 614 #define CMO_FREE_HINT_DEFAULT 1
 615 static int cmo_free_hint_flag = CMO_FREE_HINT_DEFAULT;
 616
 617 static int __init cmo_free_hint(char *str)
 618 {
 619         char *parm;
 620         parm = strstrip(str);
 621
 622         if (strcasecmp(parm, "no") == 0 || strcasecmp(parm, "off") == 0) {
 623                 printk(KERN_INFO "cmo_free_hint: CMO free page hinting is not active.\n");
 624                 cmo_free_hint_flag = 0;
 625                 return 1;
 626         }
 627
 628         cmo_free_hint_flag = 1;
 629         printk(KERN_INFO "cmo_free_hint: CMO free page hinting is active.\n");
 630
 631         if (strcasecmp(parm, "yes") == 0 || strcasecmp(parm, "on") == 0)
 632                 return 1;
 633
 634         return 0;
 635 }
 636
 637 __setup("cmo_free_hint=", cmo_free_hint);
 638
 639 static void pSeries_set_page_state(struct page *page, int order,
 640                                    unsigned long state)
 641 {
 642         int i, j;
 643         unsigned long cmo_page_sz, addr;
 644
 645         cmo_page_sz = cmo_get_page_size();
 646         addr = __pa((unsigned long)page_address(page));
 647
 648         for (i = 0; i < (1 << order); i++, addr += PAGE_SIZE) {
 649                 for (j = 0; j < PAGE_SIZE; j += cmo_page_sz)
 650                         plpar_hcall_norets(H_PAGE_INIT, state, addr + j, 0);
 651         }
 652 }
 653
 654 void arch_free_page(struct page *page, int order)
 655 {
 656         if (!cmo_free_hint_flag || !firmware_has_feature(FW_FEATURE_CMO))
 657                 return;
 658
 659         pSeries_set_page_state(page, order, H_PAGE_SET_UNUSED);
 660 }
 661 EXPORT_SYMBOL(arch_free_page);
 662
 663 #endif