linux/arch/mips/mm/page.c
<<
>>
Prefs
   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 __cpuinitdata labels[5];
  70static struct uasm_reloc __cpuinitdata 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 __cpuinitdata;
  76static int pref_bias_copy_load __cpuinitdata;
  77static int pref_bias_copy_store __cpuinitdata;
  78
  79static u32 pref_src_mode __cpuinitdata;
  80static u32 pref_dst_mode __cpuinitdata;
  81
  82static int clear_word_size __cpuinitdata;
  83static int copy_word_size __cpuinitdata;
  84
  85static int half_clear_loop_size __cpuinitdata;
  86static int half_copy_loop_size __cpuinitdata;
  87
  88static int cache_line_size __cpuinitdata;
  89#define cache_line_mask() (cache_line_size - 1)
  90
  91static inline void __cpuinit
  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 __cpuinit 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_RM9000:
 144                        /*
 145                         * As a workaround for erratum G105 which make the
 146                         * PrepareForStore hint unusable we fall back to
 147                         * StoreRetained on the RM9000.  Once it is known which
 148                         * versions of the RM9000 we'll be able to condition-
 149                         * alize this.
 150                         */
 151
 152                case CPU_R10000:
 153                case CPU_R12000:
 154                case CPU_R14000:
 155                        /*
 156                         * Those values have been experimentally tuned for an
 157                         * Origin 200.
 158                         */
 159                        pref_bias_clear_store = 512;
 160                        pref_bias_copy_load = 256;
 161                        pref_bias_copy_store = 256;
 162                        pref_src_mode = Pref_LoadStreamed;
 163                        pref_dst_mode = Pref_StoreStreamed;
 164                        break;
 165
 166                case CPU_SB1:
 167                case CPU_SB1A:
 168                        pref_bias_clear_store = 128;
 169                        pref_bias_copy_load = 128;
 170                        pref_bias_copy_store = 128;
 171                        /*
 172                         * SB1 pass1 Pref_LoadStreamed/Pref_StoreStreamed
 173                         * hints are broken.
 174                         */
 175                        if (current_cpu_type() == CPU_SB1 &&
 176                            (current_cpu_data.processor_id & 0xff) < 0x02) {
 177                                pref_src_mode = Pref_Load;
 178                                pref_dst_mode = Pref_Store;
 179                        } else {
 180                                pref_src_mode = Pref_LoadStreamed;
 181                                pref_dst_mode = Pref_StoreStreamed;
 182                        }
 183                        break;
 184
 185                default:
 186                        pref_bias_clear_store = 128;
 187                        pref_bias_copy_load = 256;
 188                        pref_bias_copy_store = 128;
 189                        pref_src_mode = Pref_LoadStreamed;
 190                        pref_dst_mode = Pref_PrepareForStore;
 191                        break;
 192                }
 193        } else {
 194                if (cpu_has_cache_cdex_s)
 195                        cache_line_size = cpu_scache_line_size();
 196                else if (cpu_has_cache_cdex_p)
 197                        cache_line_size = cpu_dcache_line_size();
 198        }
 199        /*
 200         * Too much unrolling will overflow the available space in
 201         * clear_space_array / copy_page_array.
 202         */
 203        half_clear_loop_size = min(16 * clear_word_size,
 204                                   max(cache_line_size >> 1,
 205                                       4 * clear_word_size));
 206        half_copy_loop_size = min(16 * copy_word_size,
 207                                  max(cache_line_size >> 1,
 208                                      4 * copy_word_size));
 209}
 210
 211static void __cpuinit build_clear_store(u32 **buf, int off)
 212{
 213        if (cpu_has_64bit_gp_regs || cpu_has_64bit_zero_reg) {
 214                uasm_i_sd(buf, ZERO, off, A0);
 215        } else {
 216                uasm_i_sw(buf, ZERO, off, A0);
 217        }
 218}
 219
 220static inline void __cpuinit build_clear_pref(u32 **buf, int off)
 221{
 222        if (off & cache_line_mask())
 223                return;
 224
 225        if (pref_bias_clear_store) {
 226                uasm_i_pref(buf, pref_dst_mode, pref_bias_clear_store + off,
 227                            A0);
 228        } else if (cache_line_size == (half_clear_loop_size << 1)) {
 229                if (cpu_has_cache_cdex_s) {
 230                        uasm_i_cache(buf, Create_Dirty_Excl_SD, off, A0);
 231                } else if (cpu_has_cache_cdex_p) {
 232                        if (R4600_V1_HIT_CACHEOP_WAR && cpu_is_r4600_v1_x()) {
 233                                uasm_i_nop(buf);
 234                                uasm_i_nop(buf);
 235                                uasm_i_nop(buf);
 236                                uasm_i_nop(buf);
 237                        }
 238
 239                        if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
 240                                uasm_i_lw(buf, ZERO, ZERO, AT);
 241
 242                        uasm_i_cache(buf, Create_Dirty_Excl_D, off, A0);
 243                }
 244                }
 245}
 246
 247extern u32 __clear_page_start;
 248extern u32 __clear_page_end;
 249extern u32 __copy_page_start;
 250extern u32 __copy_page_end;
 251
 252void __cpuinit build_clear_page(void)
 253{
 254        int off;
 255        u32 *buf = &__clear_page_start;
 256        struct uasm_label *l = labels;
 257        struct uasm_reloc *r = relocs;
 258        int i;
 259
 260        memset(labels, 0, sizeof(labels));
 261        memset(relocs, 0, sizeof(relocs));
 262
 263        set_prefetch_parameters();
 264
 265        /*
 266         * This algorithm makes the following assumptions:
 267         *   - The prefetch bias is a multiple of 2 words.
 268         *   - The prefetch bias is less than one page.
 269         */
 270        BUG_ON(pref_bias_clear_store % (2 * clear_word_size));
 271        BUG_ON(PAGE_SIZE < pref_bias_clear_store);
 272
 273        off = PAGE_SIZE - pref_bias_clear_store;
 274        if (off > 0xffff || !pref_bias_clear_store)
 275                pg_addiu(&buf, A2, A0, off);
 276        else
 277                uasm_i_ori(&buf, A2, A0, off);
 278
 279        if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
 280                uasm_i_lui(&buf, AT, 0xa000);
 281
 282        off = cache_line_size ? min(8, pref_bias_clear_store / cache_line_size)
 283                                * cache_line_size : 0;
 284        while (off) {
 285                build_clear_pref(&buf, -off);
 286                off -= cache_line_size;
 287        }
 288        uasm_l_clear_pref(&l, buf);
 289        do {
 290                build_clear_pref(&buf, off);
 291                build_clear_store(&buf, off);
 292                off += clear_word_size;
 293        } while (off < half_clear_loop_size);
 294        pg_addiu(&buf, A0, A0, 2 * off);
 295        off = -off;
 296        do {
 297                build_clear_pref(&buf, off);
 298                if (off == -clear_word_size)
 299                        uasm_il_bne(&buf, &r, A0, A2, label_clear_pref);
 300                build_clear_store(&buf, off);
 301                off += clear_word_size;
 302        } while (off < 0);
 303
 304        if (pref_bias_clear_store) {
 305                pg_addiu(&buf, A2, A0, pref_bias_clear_store);
 306                uasm_l_clear_nopref(&l, buf);
 307                off = 0;
 308                do {
 309                        build_clear_store(&buf, off);
 310                        off += clear_word_size;
 311                } while (off < half_clear_loop_size);
 312                pg_addiu(&buf, A0, A0, 2 * off);
 313                off = -off;
 314                do {
 315                        if (off == -clear_word_size)
 316                                uasm_il_bne(&buf, &r, A0, A2,
 317                                            label_clear_nopref);
 318                        build_clear_store(&buf, off);
 319                        off += clear_word_size;
 320                } while (off < 0);
 321        }
 322
 323        uasm_i_jr(&buf, RA);
 324        uasm_i_nop(&buf);
 325
 326        BUG_ON(buf > &__clear_page_end);
 327
 328        uasm_resolve_relocs(relocs, labels);
 329
 330        pr_debug("Synthesized clear page handler (%u instructions).\n",
 331                 (u32)(buf - &__clear_page_start));
 332
 333        pr_debug("\t.set push\n");
 334        pr_debug("\t.set noreorder\n");
 335        for (i = 0; i < (buf - &__clear_page_start); i++)
 336                pr_debug("\t.word 0x%08x\n", (&__clear_page_start)[i]);
 337        pr_debug("\t.set pop\n");
 338}
 339
 340static void __cpuinit build_copy_load(u32 **buf, int reg, int off)
 341{
 342        if (cpu_has_64bit_gp_regs) {
 343                uasm_i_ld(buf, reg, off, A1);
 344        } else {
 345                uasm_i_lw(buf, reg, off, A1);
 346        }
 347}
 348
 349static void __cpuinit build_copy_store(u32 **buf, int reg, int off)
 350{
 351        if (cpu_has_64bit_gp_regs) {
 352                uasm_i_sd(buf, reg, off, A0);
 353        } else {
 354                uasm_i_sw(buf, reg, off, A0);
 355        }
 356}
 357
 358static inline void build_copy_load_pref(u32 **buf, int off)
 359{
 360        if (off & cache_line_mask())
 361                return;
 362
 363        if (pref_bias_copy_load)
 364                uasm_i_pref(buf, pref_src_mode, pref_bias_copy_load + off, A1);
 365}
 366
 367static inline void build_copy_store_pref(u32 **buf, int off)
 368{
 369        if (off & cache_line_mask())
 370                return;
 371
 372        if (pref_bias_copy_store) {
 373                uasm_i_pref(buf, pref_dst_mode, pref_bias_copy_store + off,
 374                            A0);
 375        } else if (cache_line_size == (half_copy_loop_size << 1)) {
 376                if (cpu_has_cache_cdex_s) {
 377                        uasm_i_cache(buf, Create_Dirty_Excl_SD, off, A0);
 378                } else if (cpu_has_cache_cdex_p) {
 379                        if (R4600_V1_HIT_CACHEOP_WAR && cpu_is_r4600_v1_x()) {
 380                                uasm_i_nop(buf);
 381                                uasm_i_nop(buf);
 382                                uasm_i_nop(buf);
 383                                uasm_i_nop(buf);
 384                        }
 385
 386                        if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
 387                                uasm_i_lw(buf, ZERO, ZERO, AT);
 388
 389                        uasm_i_cache(buf, Create_Dirty_Excl_D, off, A0);
 390                }
 391        }
 392}
 393
 394void __cpuinit build_copy_page(void)
 395{
 396        int off;
 397        u32 *buf = &__copy_page_start;
 398        struct uasm_label *l = labels;
 399        struct uasm_reloc *r = relocs;
 400        int i;
 401
 402        memset(labels, 0, sizeof(labels));
 403        memset(relocs, 0, sizeof(relocs));
 404
 405        set_prefetch_parameters();
 406
 407        /*
 408         * This algorithm makes the following assumptions:
 409         *   - All prefetch biases are multiples of 8 words.
 410         *   - The prefetch biases are less than one page.
 411         *   - The store prefetch bias isn't greater than the load
 412         *     prefetch bias.
 413         */
 414        BUG_ON(pref_bias_copy_load % (8 * copy_word_size));
 415        BUG_ON(pref_bias_copy_store % (8 * copy_word_size));
 416        BUG_ON(PAGE_SIZE < pref_bias_copy_load);
 417        BUG_ON(pref_bias_copy_store > pref_bias_copy_load);
 418
 419        off = PAGE_SIZE - pref_bias_copy_load;
 420        if (off > 0xffff || !pref_bias_copy_load)
 421                pg_addiu(&buf, A2, A0, off);
 422        else
 423                uasm_i_ori(&buf, A2, A0, off);
 424
 425        if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
 426                uasm_i_lui(&buf, AT, 0xa000);
 427
 428        off = cache_line_size ? min(8, pref_bias_copy_load / cache_line_size) *
 429                                cache_line_size : 0;
 430        while (off) {
 431                build_copy_load_pref(&buf, -off);
 432                off -= cache_line_size;
 433        }
 434        off = cache_line_size ? min(8, pref_bias_copy_store / cache_line_size) *
 435                                cache_line_size : 0;
 436        while (off) {
 437                build_copy_store_pref(&buf, -off);
 438                off -= cache_line_size;
 439        }
 440        uasm_l_copy_pref_both(&l, buf);
 441        do {
 442                build_copy_load_pref(&buf, off);
 443                build_copy_load(&buf, T0, off);
 444                build_copy_load_pref(&buf, off + copy_word_size);
 445                build_copy_load(&buf, T1, off + copy_word_size);
 446                build_copy_load_pref(&buf, off + 2 * copy_word_size);
 447                build_copy_load(&buf, T2, off + 2 * copy_word_size);
 448                build_copy_load_pref(&buf, off + 3 * copy_word_size);
 449                build_copy_load(&buf, T3, off + 3 * copy_word_size);
 450                build_copy_store_pref(&buf, off);
 451                build_copy_store(&buf, T0, off);
 452                build_copy_store_pref(&buf, off + copy_word_size);
 453                build_copy_store(&buf, T1, off + copy_word_size);
 454                build_copy_store_pref(&buf, off + 2 * copy_word_size);
 455                build_copy_store(&buf, T2, off + 2 * copy_word_size);
 456                build_copy_store_pref(&buf, off + 3 * copy_word_size);
 457                build_copy_store(&buf, T3, off + 3 * copy_word_size);
 458                off += 4 * copy_word_size;
 459        } while (off < half_copy_loop_size);
 460        pg_addiu(&buf, A1, A1, 2 * off);
 461        pg_addiu(&buf, A0, A0, 2 * off);
 462        off = -off;
 463        do {
 464                build_copy_load_pref(&buf, off);
 465                build_copy_load(&buf, T0, off);
 466                build_copy_load_pref(&buf, off + copy_word_size);
 467                build_copy_load(&buf, T1, off + copy_word_size);
 468                build_copy_load_pref(&buf, off + 2 * copy_word_size);
 469                build_copy_load(&buf, T2, off + 2 * copy_word_size);
 470                build_copy_load_pref(&buf, off + 3 * copy_word_size);
 471                build_copy_load(&buf, T3, off + 3 * copy_word_size);
 472                build_copy_store_pref(&buf, off);
 473                build_copy_store(&buf, T0, off);
 474                build_copy_store_pref(&buf, off + copy_word_size);
 475                build_copy_store(&buf, T1, off + copy_word_size);
 476                build_copy_store_pref(&buf, off + 2 * copy_word_size);
 477                build_copy_store(&buf, T2, off + 2 * copy_word_size);
 478                build_copy_store_pref(&buf, off + 3 * copy_word_size);
 479                if (off == -(4 * copy_word_size))
 480                        uasm_il_bne(&buf, &r, A2, A0, label_copy_pref_both);
 481                build_copy_store(&buf, T3, off + 3 * copy_word_size);
 482                off += 4 * copy_word_size;
 483        } while (off < 0);
 484
 485        if (pref_bias_copy_load - pref_bias_copy_store) {
 486                pg_addiu(&buf, A2, A0,
 487                         pref_bias_copy_load - pref_bias_copy_store);
 488                uasm_l_copy_pref_store(&l, buf);
 489                off = 0;
 490                do {
 491                        build_copy_load(&buf, T0, off);
 492                        build_copy_load(&buf, T1, off + copy_word_size);
 493                        build_copy_load(&buf, T2, off + 2 * copy_word_size);
 494                        build_copy_load(&buf, T3, off + 3 * copy_word_size);
 495                        build_copy_store_pref(&buf, off);
 496                        build_copy_store(&buf, T0, off);
 497                        build_copy_store_pref(&buf, off + copy_word_size);
 498                        build_copy_store(&buf, T1, off + copy_word_size);
 499                        build_copy_store_pref(&buf, off + 2 * copy_word_size);
 500                        build_copy_store(&buf, T2, off + 2 * copy_word_size);
 501                        build_copy_store_pref(&buf, off + 3 * copy_word_size);
 502                        build_copy_store(&buf, T3, off + 3 * copy_word_size);
 503                        off += 4 * copy_word_size;
 504                } while (off < half_copy_loop_size);
 505                pg_addiu(&buf, A1, A1, 2 * off);
 506                pg_addiu(&buf, A0, A0, 2 * off);
 507                off = -off;
 508                do {
 509                        build_copy_load(&buf, T0, off);
 510                        build_copy_load(&buf, T1, off + copy_word_size);
 511                        build_copy_load(&buf, T2, off + 2 * copy_word_size);
 512                        build_copy_load(&buf, T3, off + 3 * copy_word_size);
 513                        build_copy_store_pref(&buf, off);
 514                        build_copy_store(&buf, T0, off);
 515                        build_copy_store_pref(&buf, off + copy_word_size);
 516                        build_copy_store(&buf, T1, off + copy_word_size);
 517                        build_copy_store_pref(&buf, off + 2 * copy_word_size);
 518                        build_copy_store(&buf, T2, off + 2 * copy_word_size);
 519                        build_copy_store_pref(&buf, off + 3 * copy_word_size);
 520                        if (off == -(4 * copy_word_size))
 521                                uasm_il_bne(&buf, &r, A2, A0,
 522                                            label_copy_pref_store);
 523                        build_copy_store(&buf, T3, off + 3 * copy_word_size);
 524                        off += 4 * copy_word_size;
 525                } while (off < 0);
 526        }
 527
 528        if (pref_bias_copy_store) {
 529                pg_addiu(&buf, A2, A0, pref_bias_copy_store);
 530                uasm_l_copy_nopref(&l, buf);
 531                off = 0;
 532                do {
 533                        build_copy_load(&buf, T0, off);
 534                        build_copy_load(&buf, T1, off + copy_word_size);
 535                        build_copy_load(&buf, T2, off + 2 * copy_word_size);
 536                        build_copy_load(&buf, T3, off + 3 * copy_word_size);
 537                        build_copy_store(&buf, T0, off);
 538                        build_copy_store(&buf, T1, off + copy_word_size);
 539                        build_copy_store(&buf, T2, off + 2 * copy_word_size);
 540                        build_copy_store(&buf, T3, off + 3 * copy_word_size);
 541                        off += 4 * copy_word_size;
 542                } while (off < half_copy_loop_size);
 543                pg_addiu(&buf, A1, A1, 2 * off);
 544                pg_addiu(&buf, A0, A0, 2 * off);
 545                off = -off;
 546                do {
 547                        build_copy_load(&buf, T0, off);
 548                        build_copy_load(&buf, T1, off + copy_word_size);
 549                        build_copy_load(&buf, T2, off + 2 * copy_word_size);
 550                        build_copy_load(&buf, T3, off + 3 * copy_word_size);
 551                        build_copy_store(&buf, T0, off);
 552                        build_copy_store(&buf, T1, off + copy_word_size);
 553                        build_copy_store(&buf, T2, off + 2 * copy_word_size);
 554                        if (off == -(4 * copy_word_size))
 555                                uasm_il_bne(&buf, &r, A2, A0,
 556                                            label_copy_nopref);
 557                        build_copy_store(&buf, T3, off + 3 * copy_word_size);
 558                        off += 4 * copy_word_size;
 559                } while (off < 0);
 560        }
 561
 562        uasm_i_jr(&buf, RA);
 563        uasm_i_nop(&buf);
 564
 565        BUG_ON(buf > &__copy_page_end);
 566
 567        uasm_resolve_relocs(relocs, labels);
 568
 569        pr_debug("Synthesized copy page handler (%u instructions).\n",
 570                 (u32)(buf - &__copy_page_start));
 571
 572        pr_debug("\t.set push\n");
 573        pr_debug("\t.set noreorder\n");
 574        for (i = 0; i < (buf - &__copy_page_start); i++)
 575                pr_debug("\t.word 0x%08x\n", (&__copy_page_start)[i]);
 576        pr_debug("\t.set pop\n");
 577}
 578
 579#ifdef CONFIG_SIBYTE_DMA_PAGEOPS
 580extern void clear_page_cpu(void *page);
 581extern void copy_page_cpu(void *to, void *from);
 582
 583/*
 584 * Pad descriptors to cacheline, since each is exclusively owned by a
 585 * particular CPU.
 586 */
 587struct dmadscr {
 588        u64 dscr_a;
 589        u64 dscr_b;
 590        u64 pad_a;
 591        u64 pad_b;
 592} ____cacheline_aligned_in_smp page_descr[DM_NUM_CHANNELS];
 593
 594void sb1_dma_init(void)
 595{
 596        int i;
 597
 598        for (i = 0; i < DM_NUM_CHANNELS; i++) {
 599                const u64 base_val = CPHYSADDR((unsigned long)&page_descr[i]) |
 600                                     V_DM_DSCR_BASE_RINGSZ(1);
 601                void *base_reg = IOADDR(A_DM_REGISTER(i, R_DM_DSCR_BASE));
 602
 603                __raw_writeq(base_val, base_reg);
 604                __raw_writeq(base_val | M_DM_DSCR_BASE_RESET, base_reg);
 605                __raw_writeq(base_val | M_DM_DSCR_BASE_ENABL, base_reg);
 606        }
 607}
 608
 609void clear_page(void *page)
 610{
 611        u64 to_phys = CPHYSADDR((unsigned long)page);
 612        unsigned int cpu = smp_processor_id();
 613
 614        /* if the page is not in KSEG0, use old way */
 615        if ((long)KSEGX((unsigned long)page) != (long)CKSEG0)
 616                return clear_page_cpu(page);
 617
 618        page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_ZERO_MEM |
 619                                 M_DM_DSCRA_L2C_DEST | M_DM_DSCRA_INTERRUPT;
 620        page_descr[cpu].dscr_b = V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE);
 621        __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT)));
 622
 623        /*
 624         * Don't really want to do it this way, but there's no
 625         * reliable way to delay completion detection.
 626         */
 627        while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG)))
 628                 & M_DM_DSCR_BASE_INTERRUPT))
 629                ;
 630        __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE)));
 631}
 632
 633void copy_page(void *to, void *from)
 634{
 635        u64 from_phys = CPHYSADDR((unsigned long)from);
 636        u64 to_phys = CPHYSADDR((unsigned long)to);
 637        unsigned int cpu = smp_processor_id();
 638
 639        /* if any page is not in KSEG0, use old way */
 640        if ((long)KSEGX((unsigned long)to) != (long)CKSEG0
 641            || (long)KSEGX((unsigned long)from) != (long)CKSEG0)
 642                return copy_page_cpu(to, from);
 643
 644        page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_L2C_DEST |
 645                                 M_DM_DSCRA_INTERRUPT;
 646        page_descr[cpu].dscr_b = from_phys | V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE);
 647        __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT)));
 648
 649        /*
 650         * Don't really want to do it this way, but there's no
 651         * reliable way to delay completion detection.
 652         */
 653        while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG)))
 654                 & M_DM_DSCR_BASE_INTERRUPT))
 655                ;
 656        __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE)));
 657}
 658
 659#endif /* CONFIG_SIBYTE_DMA_PAGEOPS */
 660