linux/arch/mips/mm/page.c
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   1/*
   2 * This file is subject to the terms and conditions of the GNU General Public
   3 * License.  See the file "COPYING" in the main directory of this archive
   4 * for more details.
   5 *
   6 * Copyright (C) 2003, 04, 05 Ralf Baechle (ralf@linux-mips.org)
   7 * Copyright (C) 2007  Maciej W. Rozycki
   8 * Copyright (C) 2008  Thiemo Seufer
   9 * Copyright (C) 2012  MIPS Technologies, Inc.
  10 */
  11#include <linux/init.h>
  12#include <linux/kernel.h>
  13#include <linux/sched.h>
  14#include <linux/smp.h>
  15#include <linux/mm.h>
  16#include <linux/module.h>
  17#include <linux/proc_fs.h>
  18
  19#include <asm/bugs.h>
  20#include <asm/cacheops.h>
  21#include <asm/inst.h>
  22#include <asm/io.h>
  23#include <asm/page.h>
  24#include <asm/pgtable.h>
  25#include <asm/prefetch.h>
  26#include <asm/bootinfo.h>
  27#include <asm/mipsregs.h>
  28#include <asm/mmu_context.h>
  29#include <asm/cpu.h>
  30#include <asm/war.h>
  31
  32#ifdef CONFIG_SIBYTE_DMA_PAGEOPS
  33#include <asm/sibyte/sb1250.h>
  34#include <asm/sibyte/sb1250_regs.h>
  35#include <asm/sibyte/sb1250_dma.h>
  36#endif
  37
  38#include <asm/uasm.h>
  39
  40/* Registers used in the assembled routines. */
  41#define ZERO 0
  42#define AT 2
  43#define A0 4
  44#define A1 5
  45#define A2 6
  46#define T0 8
  47#define T1 9
  48#define T2 10
  49#define T3 11
  50#define T9 25
  51#define RA 31
  52
  53/* Handle labels (which must be positive integers). */
  54enum label_id {
  55        label_clear_nopref = 1,
  56        label_clear_pref,
  57        label_copy_nopref,
  58        label_copy_pref_both,
  59        label_copy_pref_store,
  60};
  61
  62UASM_L_LA(_clear_nopref)
  63UASM_L_LA(_clear_pref)
  64UASM_L_LA(_copy_nopref)
  65UASM_L_LA(_copy_pref_both)
  66UASM_L_LA(_copy_pref_store)
  67
  68/* We need one branch and therefore one relocation per target label. */
  69static struct uasm_label labels[5];
  70static struct uasm_reloc relocs[5];
  71
  72#define cpu_is_r4600_v1_x()     ((read_c0_prid() & 0xfffffff0) == 0x00002010)
  73#define cpu_is_r4600_v2_x()     ((read_c0_prid() & 0xfffffff0) == 0x00002020)
  74
  75static int pref_bias_clear_store;
  76static int pref_bias_copy_load;
  77static int pref_bias_copy_store;
  78
  79static u32 pref_src_mode;
  80static u32 pref_dst_mode;
  81
  82static int clear_word_size;
  83static int copy_word_size;
  84
  85static int half_clear_loop_size;
  86static int half_copy_loop_size;
  87
  88static int cache_line_size;
  89#define cache_line_mask() (cache_line_size - 1)
  90
  91static inline void
  92pg_addiu(u32 **buf, unsigned int reg1, unsigned int reg2, unsigned int off)
  93{
  94        if (cpu_has_64bit_gp_regs && DADDI_WAR && r4k_daddiu_bug()) {
  95                if (off > 0x7fff) {
  96                        uasm_i_lui(buf, T9, uasm_rel_hi(off));
  97                        uasm_i_addiu(buf, T9, T9, uasm_rel_lo(off));
  98                } else
  99                        uasm_i_addiu(buf, T9, ZERO, off);
 100                uasm_i_daddu(buf, reg1, reg2, T9);
 101        } else {
 102                if (off > 0x7fff) {
 103                        uasm_i_lui(buf, T9, uasm_rel_hi(off));
 104                        uasm_i_addiu(buf, T9, T9, uasm_rel_lo(off));
 105                        UASM_i_ADDU(buf, reg1, reg2, T9);
 106                } else
 107                        UASM_i_ADDIU(buf, reg1, reg2, off);
 108        }
 109}
 110
 111static void set_prefetch_parameters(void)
 112{
 113        if (cpu_has_64bit_gp_regs || cpu_has_64bit_zero_reg)
 114                clear_word_size = 8;
 115        else
 116                clear_word_size = 4;
 117
 118        if (cpu_has_64bit_gp_regs)
 119                copy_word_size = 8;
 120        else
 121                copy_word_size = 4;
 122
 123        /*
 124         * The pref's used here are using "streaming" hints, which cause the
 125         * copied data to be kicked out of the cache sooner.  A page copy often
 126         * ends up copying a lot more data than is commonly used, so this seems
 127         * to make sense in terms of reducing cache pollution, but I've no real
 128         * performance data to back this up.
 129         */
 130        if (cpu_has_prefetch) {
 131                /*
 132                 * XXX: Most prefetch bias values in here are based on
 133                 * guesswork.
 134                 */
 135                cache_line_size = cpu_dcache_line_size();
 136                switch (current_cpu_type()) {
 137                case CPU_R5500:
 138                case CPU_TX49XX:
 139                        /* These processors only support the Pref_Load. */
 140                        pref_bias_copy_load = 256;
 141                        break;
 142
 143                case CPU_R10000:
 144                case CPU_R12000:
 145                case CPU_R14000:
 146                        /*
 147                         * Those values have been experimentally tuned for an
 148                         * Origin 200.
 149                         */
 150                        pref_bias_clear_store = 512;
 151                        pref_bias_copy_load = 256;
 152                        pref_bias_copy_store = 256;
 153                        pref_src_mode = Pref_LoadStreamed;
 154                        pref_dst_mode = Pref_StoreStreamed;
 155                        break;
 156
 157                case CPU_SB1:
 158                case CPU_SB1A:
 159                        pref_bias_clear_store = 128;
 160                        pref_bias_copy_load = 128;
 161                        pref_bias_copy_store = 128;
 162                        /*
 163                         * SB1 pass1 Pref_LoadStreamed/Pref_StoreStreamed
 164                         * hints are broken.
 165                         */
 166                        if (current_cpu_type() == CPU_SB1 &&
 167                            (current_cpu_data.processor_id & 0xff) < 0x02) {
 168                                pref_src_mode = Pref_Load;
 169                                pref_dst_mode = Pref_Store;
 170                        } else {
 171                                pref_src_mode = Pref_LoadStreamed;
 172                                pref_dst_mode = Pref_StoreStreamed;
 173                        }
 174                        break;
 175
 176                default:
 177                        pref_bias_clear_store = 128;
 178                        pref_bias_copy_load = 256;
 179                        pref_bias_copy_store = 128;
 180                        pref_src_mode = Pref_LoadStreamed;
 181                        pref_dst_mode = Pref_PrepareForStore;
 182                        break;
 183                }
 184        } else {
 185                if (cpu_has_cache_cdex_s)
 186                        cache_line_size = cpu_scache_line_size();
 187                else if (cpu_has_cache_cdex_p)
 188                        cache_line_size = cpu_dcache_line_size();
 189        }
 190        /*
 191         * Too much unrolling will overflow the available space in
 192         * clear_space_array / copy_page_array.
 193         */
 194        half_clear_loop_size = min(16 * clear_word_size,
 195                                   max(cache_line_size >> 1,
 196                                       4 * clear_word_size));
 197        half_copy_loop_size = min(16 * copy_word_size,
 198                                  max(cache_line_size >> 1,
 199                                      4 * copy_word_size));
 200}
 201
 202static void build_clear_store(u32 **buf, int off)
 203{
 204        if (cpu_has_64bit_gp_regs || cpu_has_64bit_zero_reg) {
 205                uasm_i_sd(buf, ZERO, off, A0);
 206        } else {
 207                uasm_i_sw(buf, ZERO, off, A0);
 208        }
 209}
 210
 211static inline void build_clear_pref(u32 **buf, int off)
 212{
 213        if (off & cache_line_mask())
 214                return;
 215
 216        if (pref_bias_clear_store) {
 217                uasm_i_pref(buf, pref_dst_mode, pref_bias_clear_store + off,
 218                            A0);
 219        } else if (cache_line_size == (half_clear_loop_size << 1)) {
 220                if (cpu_has_cache_cdex_s) {
 221                        uasm_i_cache(buf, Create_Dirty_Excl_SD, off, A0);
 222                } else if (cpu_has_cache_cdex_p) {
 223                        if (R4600_V1_HIT_CACHEOP_WAR && cpu_is_r4600_v1_x()) {
 224                                uasm_i_nop(buf);
 225                                uasm_i_nop(buf);
 226                                uasm_i_nop(buf);
 227                                uasm_i_nop(buf);
 228                        }
 229
 230                        if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
 231                                uasm_i_lw(buf, ZERO, ZERO, AT);
 232
 233                        uasm_i_cache(buf, Create_Dirty_Excl_D, off, A0);
 234                }
 235        }
 236}
 237
 238extern u32 __clear_page_start;
 239extern u32 __clear_page_end;
 240extern u32 __copy_page_start;
 241extern u32 __copy_page_end;
 242
 243void build_clear_page(void)
 244{
 245        int off;
 246        u32 *buf = &__clear_page_start;
 247        struct uasm_label *l = labels;
 248        struct uasm_reloc *r = relocs;
 249        int i;
 250        static atomic_t run_once = ATOMIC_INIT(0);
 251
 252        if (atomic_xchg(&run_once, 1)) {
 253                return;
 254        }
 255
 256        memset(labels, 0, sizeof(labels));
 257        memset(relocs, 0, sizeof(relocs));
 258
 259        set_prefetch_parameters();
 260
 261        /*
 262         * This algorithm makes the following assumptions:
 263         *   - The prefetch bias is a multiple of 2 words.
 264         *   - The prefetch bias is less than one page.
 265         */
 266        BUG_ON(pref_bias_clear_store % (2 * clear_word_size));
 267        BUG_ON(PAGE_SIZE < pref_bias_clear_store);
 268
 269        off = PAGE_SIZE - pref_bias_clear_store;
 270        if (off > 0xffff || !pref_bias_clear_store)
 271                pg_addiu(&buf, A2, A0, off);
 272        else
 273                uasm_i_ori(&buf, A2, A0, off);
 274
 275        if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
 276                uasm_i_lui(&buf, AT, 0xa000);
 277
 278        off = cache_line_size ? min(8, pref_bias_clear_store / cache_line_size)
 279                                * cache_line_size : 0;
 280        while (off) {
 281                build_clear_pref(&buf, -off);
 282                off -= cache_line_size;
 283        }
 284        uasm_l_clear_pref(&l, buf);
 285        do {
 286                build_clear_pref(&buf, off);
 287                build_clear_store(&buf, off);
 288                off += clear_word_size;
 289        } while (off < half_clear_loop_size);
 290        pg_addiu(&buf, A0, A0, 2 * off);
 291        off = -off;
 292        do {
 293                build_clear_pref(&buf, off);
 294                if (off == -clear_word_size)
 295                        uasm_il_bne(&buf, &r, A0, A2, label_clear_pref);
 296                build_clear_store(&buf, off);
 297                off += clear_word_size;
 298        } while (off < 0);
 299
 300        if (pref_bias_clear_store) {
 301                pg_addiu(&buf, A2, A0, pref_bias_clear_store);
 302                uasm_l_clear_nopref(&l, buf);
 303                off = 0;
 304                do {
 305                        build_clear_store(&buf, off);
 306                        off += clear_word_size;
 307                } while (off < half_clear_loop_size);
 308                pg_addiu(&buf, A0, A0, 2 * off);
 309                off = -off;
 310                do {
 311                        if (off == -clear_word_size)
 312                                uasm_il_bne(&buf, &r, A0, A2,
 313                                            label_clear_nopref);
 314                        build_clear_store(&buf, off);
 315                        off += clear_word_size;
 316                } while (off < 0);
 317        }
 318
 319        uasm_i_jr(&buf, RA);
 320        uasm_i_nop(&buf);
 321
 322        BUG_ON(buf > &__clear_page_end);
 323
 324        uasm_resolve_relocs(relocs, labels);
 325
 326        pr_debug("Synthesized clear page handler (%u instructions).\n",
 327                 (u32)(buf - &__clear_page_start));
 328
 329        pr_debug("\t.set push\n");
 330        pr_debug("\t.set noreorder\n");
 331        for (i = 0; i < (buf - &__clear_page_start); i++)
 332                pr_debug("\t.word 0x%08x\n", (&__clear_page_start)[i]);
 333        pr_debug("\t.set pop\n");
 334}
 335
 336static void build_copy_load(u32 **buf, int reg, int off)
 337{
 338        if (cpu_has_64bit_gp_regs) {
 339                uasm_i_ld(buf, reg, off, A1);
 340        } else {
 341                uasm_i_lw(buf, reg, off, A1);
 342        }
 343}
 344
 345static void build_copy_store(u32 **buf, int reg, int off)
 346{
 347        if (cpu_has_64bit_gp_regs) {
 348                uasm_i_sd(buf, reg, off, A0);
 349        } else {
 350                uasm_i_sw(buf, reg, off, A0);
 351        }
 352}
 353
 354static inline void build_copy_load_pref(u32 **buf, int off)
 355{
 356        if (off & cache_line_mask())
 357                return;
 358
 359        if (pref_bias_copy_load)
 360                uasm_i_pref(buf, pref_src_mode, pref_bias_copy_load + off, A1);
 361}
 362
 363static inline void build_copy_store_pref(u32 **buf, int off)
 364{
 365        if (off & cache_line_mask())
 366                return;
 367
 368        if (pref_bias_copy_store) {
 369                uasm_i_pref(buf, pref_dst_mode, pref_bias_copy_store + off,
 370                            A0);
 371        } else if (cache_line_size == (half_copy_loop_size << 1)) {
 372                if (cpu_has_cache_cdex_s) {
 373                        uasm_i_cache(buf, Create_Dirty_Excl_SD, off, A0);
 374                } else if (cpu_has_cache_cdex_p) {
 375                        if (R4600_V1_HIT_CACHEOP_WAR && cpu_is_r4600_v1_x()) {
 376                                uasm_i_nop(buf);
 377                                uasm_i_nop(buf);
 378                                uasm_i_nop(buf);
 379                                uasm_i_nop(buf);
 380                        }
 381
 382                        if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
 383                                uasm_i_lw(buf, ZERO, ZERO, AT);
 384
 385                        uasm_i_cache(buf, Create_Dirty_Excl_D, off, A0);
 386                }
 387        }
 388}
 389
 390void build_copy_page(void)
 391{
 392        int off;
 393        u32 *buf = &__copy_page_start;
 394        struct uasm_label *l = labels;
 395        struct uasm_reloc *r = relocs;
 396        int i;
 397        static atomic_t run_once = ATOMIC_INIT(0);
 398
 399        if (atomic_xchg(&run_once, 1)) {
 400                return;
 401        }
 402
 403        memset(labels, 0, sizeof(labels));
 404        memset(relocs, 0, sizeof(relocs));
 405
 406        set_prefetch_parameters();
 407
 408        /*
 409         * This algorithm makes the following assumptions:
 410         *   - All prefetch biases are multiples of 8 words.
 411         *   - The prefetch biases are less than one page.
 412         *   - The store prefetch bias isn't greater than the load
 413         *     prefetch bias.
 414         */
 415        BUG_ON(pref_bias_copy_load % (8 * copy_word_size));
 416        BUG_ON(pref_bias_copy_store % (8 * copy_word_size));
 417        BUG_ON(PAGE_SIZE < pref_bias_copy_load);
 418        BUG_ON(pref_bias_copy_store > pref_bias_copy_load);
 419
 420        off = PAGE_SIZE - pref_bias_copy_load;
 421        if (off > 0xffff || !pref_bias_copy_load)
 422                pg_addiu(&buf, A2, A0, off);
 423        else
 424                uasm_i_ori(&buf, A2, A0, off);
 425
 426        if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
 427                uasm_i_lui(&buf, AT, 0xa000);
 428
 429        off = cache_line_size ? min(8, pref_bias_copy_load / cache_line_size) *
 430                                cache_line_size : 0;
 431        while (off) {
 432                build_copy_load_pref(&buf, -off);
 433                off -= cache_line_size;
 434        }
 435        off = cache_line_size ? min(8, pref_bias_copy_store / cache_line_size) *
 436                                cache_line_size : 0;
 437        while (off) {
 438                build_copy_store_pref(&buf, -off);
 439                off -= cache_line_size;
 440        }
 441        uasm_l_copy_pref_both(&l, buf);
 442        do {
 443                build_copy_load_pref(&buf, off);
 444                build_copy_load(&buf, T0, off);
 445                build_copy_load_pref(&buf, off + copy_word_size);
 446                build_copy_load(&buf, T1, off + copy_word_size);
 447                build_copy_load_pref(&buf, off + 2 * copy_word_size);
 448                build_copy_load(&buf, T2, off + 2 * copy_word_size);
 449                build_copy_load_pref(&buf, off + 3 * copy_word_size);
 450                build_copy_load(&buf, T3, off + 3 * copy_word_size);
 451                build_copy_store_pref(&buf, off);
 452                build_copy_store(&buf, T0, off);
 453                build_copy_store_pref(&buf, off + copy_word_size);
 454                build_copy_store(&buf, T1, off + copy_word_size);
 455                build_copy_store_pref(&buf, off + 2 * copy_word_size);
 456                build_copy_store(&buf, T2, off + 2 * copy_word_size);
 457                build_copy_store_pref(&buf, off + 3 * copy_word_size);
 458                build_copy_store(&buf, T3, off + 3 * copy_word_size);
 459                off += 4 * copy_word_size;
 460        } while (off < half_copy_loop_size);
 461        pg_addiu(&buf, A1, A1, 2 * off);
 462        pg_addiu(&buf, A0, A0, 2 * off);
 463        off = -off;
 464        do {
 465                build_copy_load_pref(&buf, off);
 466                build_copy_load(&buf, T0, off);
 467                build_copy_load_pref(&buf, off + copy_word_size);
 468                build_copy_load(&buf, T1, off + copy_word_size);
 469                build_copy_load_pref(&buf, off + 2 * copy_word_size);
 470                build_copy_load(&buf, T2, off + 2 * copy_word_size);
 471                build_copy_load_pref(&buf, off + 3 * copy_word_size);
 472                build_copy_load(&buf, T3, off + 3 * copy_word_size);
 473                build_copy_store_pref(&buf, off);
 474                build_copy_store(&buf, T0, off);
 475                build_copy_store_pref(&buf, off + copy_word_size);
 476                build_copy_store(&buf, T1, off + copy_word_size);
 477                build_copy_store_pref(&buf, off + 2 * copy_word_size);
 478                build_copy_store(&buf, T2, off + 2 * copy_word_size);
 479                build_copy_store_pref(&buf, off + 3 * copy_word_size);
 480                if (off == -(4 * copy_word_size))
 481                        uasm_il_bne(&buf, &r, A2, A0, label_copy_pref_both);
 482                build_copy_store(&buf, T3, off + 3 * copy_word_size);
 483                off += 4 * copy_word_size;
 484        } while (off < 0);
 485
 486        if (pref_bias_copy_load - pref_bias_copy_store) {
 487                pg_addiu(&buf, A2, A0,
 488                         pref_bias_copy_load - pref_bias_copy_store);
 489                uasm_l_copy_pref_store(&l, buf);
 490                off = 0;
 491                do {
 492                        build_copy_load(&buf, T0, off);
 493                        build_copy_load(&buf, T1, off + copy_word_size);
 494                        build_copy_load(&buf, T2, off + 2 * copy_word_size);
 495                        build_copy_load(&buf, T3, off + 3 * copy_word_size);
 496                        build_copy_store_pref(&buf, off);
 497                        build_copy_store(&buf, T0, off);
 498                        build_copy_store_pref(&buf, off + copy_word_size);
 499                        build_copy_store(&buf, T1, off + copy_word_size);
 500                        build_copy_store_pref(&buf, off + 2 * copy_word_size);
 501                        build_copy_store(&buf, T2, off + 2 * copy_word_size);
 502                        build_copy_store_pref(&buf, off + 3 * copy_word_size);
 503                        build_copy_store(&buf, T3, off + 3 * copy_word_size);
 504                        off += 4 * copy_word_size;
 505                } while (off < half_copy_loop_size);
 506                pg_addiu(&buf, A1, A1, 2 * off);
 507                pg_addiu(&buf, A0, A0, 2 * off);
 508                off = -off;
 509                do {
 510                        build_copy_load(&buf, T0, off);
 511                        build_copy_load(&buf, T1, off + copy_word_size);
 512                        build_copy_load(&buf, T2, off + 2 * copy_word_size);
 513                        build_copy_load(&buf, T3, off + 3 * copy_word_size);
 514                        build_copy_store_pref(&buf, off);
 515                        build_copy_store(&buf, T0, off);
 516                        build_copy_store_pref(&buf, off + copy_word_size);
 517                        build_copy_store(&buf, T1, off + copy_word_size);
 518                        build_copy_store_pref(&buf, off + 2 * copy_word_size);
 519                        build_copy_store(&buf, T2, off + 2 * copy_word_size);
 520                        build_copy_store_pref(&buf, off + 3 * copy_word_size);
 521                        if (off == -(4 * copy_word_size))
 522                                uasm_il_bne(&buf, &r, A2, A0,
 523                                            label_copy_pref_store);
 524                        build_copy_store(&buf, T3, off + 3 * copy_word_size);
 525                        off += 4 * copy_word_size;
 526                } while (off < 0);
 527        }
 528
 529        if (pref_bias_copy_store) {
 530                pg_addiu(&buf, A2, A0, pref_bias_copy_store);
 531                uasm_l_copy_nopref(&l, buf);
 532                off = 0;
 533                do {
 534                        build_copy_load(&buf, T0, off);
 535                        build_copy_load(&buf, T1, off + copy_word_size);
 536                        build_copy_load(&buf, T2, off + 2 * copy_word_size);
 537                        build_copy_load(&buf, T3, off + 3 * copy_word_size);
 538                        build_copy_store(&buf, T0, off);
 539                        build_copy_store(&buf, T1, off + copy_word_size);
 540                        build_copy_store(&buf, T2, off + 2 * copy_word_size);
 541                        build_copy_store(&buf, T3, off + 3 * copy_word_size);
 542                        off += 4 * copy_word_size;
 543                } while (off < half_copy_loop_size);
 544                pg_addiu(&buf, A1, A1, 2 * off);
 545                pg_addiu(&buf, A0, A0, 2 * off);
 546                off = -off;
 547                do {
 548                        build_copy_load(&buf, T0, off);
 549                        build_copy_load(&buf, T1, off + copy_word_size);
 550                        build_copy_load(&buf, T2, off + 2 * copy_word_size);
 551                        build_copy_load(&buf, T3, off + 3 * copy_word_size);
 552                        build_copy_store(&buf, T0, off);
 553                        build_copy_store(&buf, T1, off + copy_word_size);
 554                        build_copy_store(&buf, T2, off + 2 * copy_word_size);
 555                        if (off == -(4 * copy_word_size))
 556                                uasm_il_bne(&buf, &r, A2, A0,
 557                                            label_copy_nopref);
 558                        build_copy_store(&buf, T3, off + 3 * copy_word_size);
 559                        off += 4 * copy_word_size;
 560                } while (off < 0);
 561        }
 562
 563        uasm_i_jr(&buf, RA);
 564        uasm_i_nop(&buf);
 565
 566        BUG_ON(buf > &__copy_page_end);
 567
 568        uasm_resolve_relocs(relocs, labels);
 569
 570        pr_debug("Synthesized copy page handler (%u instructions).\n",
 571                 (u32)(buf - &__copy_page_start));
 572
 573        pr_debug("\t.set push\n");
 574        pr_debug("\t.set noreorder\n");
 575        for (i = 0; i < (buf - &__copy_page_start); i++)
 576                pr_debug("\t.word 0x%08x\n", (&__copy_page_start)[i]);
 577        pr_debug("\t.set pop\n");
 578}
 579
 580#ifdef CONFIG_SIBYTE_DMA_PAGEOPS
 581extern void clear_page_cpu(void *page);
 582extern void copy_page_cpu(void *to, void *from);
 583
 584/*
 585 * Pad descriptors to cacheline, since each is exclusively owned by a
 586 * particular CPU.
 587 */
 588struct dmadscr {
 589        u64 dscr_a;
 590        u64 dscr_b;
 591        u64 pad_a;
 592        u64 pad_b;
 593} ____cacheline_aligned_in_smp page_descr[DM_NUM_CHANNELS];
 594
 595void sb1_dma_init(void)
 596{
 597        int i;
 598
 599        for (i = 0; i < DM_NUM_CHANNELS; i++) {
 600                const u64 base_val = CPHYSADDR((unsigned long)&page_descr[i]) |
 601                                     V_DM_DSCR_BASE_RINGSZ(1);
 602                void *base_reg = IOADDR(A_DM_REGISTER(i, R_DM_DSCR_BASE));
 603
 604                __raw_writeq(base_val, base_reg);
 605                __raw_writeq(base_val | M_DM_DSCR_BASE_RESET, base_reg);
 606                __raw_writeq(base_val | M_DM_DSCR_BASE_ENABL, base_reg);
 607        }
 608}
 609
 610void clear_page(void *page)
 611{
 612        u64 to_phys = CPHYSADDR((unsigned long)page);
 613        unsigned int cpu = smp_processor_id();
 614
 615        /* if the page is not in KSEG0, use old way */
 616        if ((long)KSEGX((unsigned long)page) != (long)CKSEG0)
 617                return clear_page_cpu(page);
 618
 619        page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_ZERO_MEM |
 620                                 M_DM_DSCRA_L2C_DEST | M_DM_DSCRA_INTERRUPT;
 621        page_descr[cpu].dscr_b = V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE);
 622        __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT)));
 623
 624        /*
 625         * Don't really want to do it this way, but there's no
 626         * reliable way to delay completion detection.
 627         */
 628        while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG)))
 629                 & M_DM_DSCR_BASE_INTERRUPT))
 630                ;
 631        __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE)));
 632}
 633
 634void copy_page(void *to, void *from)
 635{
 636        u64 from_phys = CPHYSADDR((unsigned long)from);
 637        u64 to_phys = CPHYSADDR((unsigned long)to);
 638        unsigned int cpu = smp_processor_id();
 639
 640        /* if any page is not in KSEG0, use old way */
 641        if ((long)KSEGX((unsigned long)to) != (long)CKSEG0
 642            || (long)KSEGX((unsigned long)from) != (long)CKSEG0)
 643                return copy_page_cpu(to, from);
 644
 645        page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_L2C_DEST |
 646                                 M_DM_DSCRA_INTERRUPT;
 647        page_descr[cpu].dscr_b = from_phys | V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE);
 648        __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT)));
 649
 650        /*
 651         * Don't really want to do it this way, but there's no
 652         * reliable way to delay completion detection.
 653         */
 654        while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG)))
 655                 & M_DM_DSCR_BASE_INTERRUPT))
 656                ;
 657        __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE)));
 658}
 659
 660#endif /* CONFIG_SIBYTE_DMA_PAGEOPS */
 661