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      1 /*
      2  * Copyright 2006 VMware, Inc.
      3  * Copyright  2006 Intel Corporation
      4  *
      5  * Permission is hereby granted, free of charge, to any person obtaining
      6  * a copy of this software and associated documentation files (the
      7  * "Software"), to deal in the Software without restriction, including
      8  * without limitation the rights to use, copy, modify, merge, publish,
      9  * distribute, sublicense, and/or sell copies of the Software, and to
     10  * permit persons to whom the Software is furnished to do so, subject to
     11  * the following conditions:
     12  *
     13  * The above copyright notice and this permission notice (including the
     14  * next paragraph) shall be included in all copies or substantial
     15  * portions of the Software.
     16  *
     17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
     20  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
     21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
     22  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
     23  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     24  */
     25 
     26 /**
     27  * \file brw_tex_layout.cpp
     28  *
     29  * Code to lay out images in a mipmap tree.
     30  *
     31  * \author Keith Whitwell <keithw (at) vmware.com>
     32  * \author Michel Dnzer <daenzer (at) vmware.com>
     33  */
     34 
     35 #include "intel_mipmap_tree.h"
     36 #include "brw_context.h"
     37 #include "main/macros.h"
     38 #include "main/glformats.h"
     39 
     40 #define FILE_DEBUG_FLAG DEBUG_MIPTREE
     41 
     42 static unsigned int
     43 tr_mode_horizontal_texture_alignment(const struct intel_mipmap_tree *mt)
     44 {
     45    unsigned ret_align, divisor, multiplier_ys;
     46 
     47    /* Values in below tables specifiy the horizontal alignment requirement
     48     * in elements for TRMODE_YF surface. An element is defined as a pixel in
     49     * uncompressed surface formats, and as a compression block in compressed
     50     * surface formats. For MSFMT_DEPTH_STENCIL type multisampled surfaces, an
     51     * element is a sample.
     52     */
     53    const unsigned align_1d_yf[] = {4096, 2048, 1024, 512, 256};
     54    const unsigned align_2d_yf[] = {64, 64, 32, 32, 16};
     55    const unsigned align_3d_yf[] = {16, 8, 8, 8, 4};
     56 
     57    assert(mt->tr_mode != INTEL_MIPTREE_TRMODE_NONE);
     58 
     59    /* Alignment computations below assume a power of 2 cpp. */
     60    assert (mt->cpp >= 1 && mt->cpp <= 16 && _mesa_is_pow_two(mt->cpp));
     61    /* Compute array index. */
     62    const int i = ffs(mt->cpp) - 1;
     63 
     64    switch(mt->target) {
     65    case GL_TEXTURE_1D:
     66    case GL_TEXTURE_1D_ARRAY:
     67       ret_align = align_1d_yf[i];
     68       multiplier_ys = 16;
     69       break;
     70    case GL_TEXTURE_2D:
     71    case GL_TEXTURE_RECTANGLE:
     72    case GL_TEXTURE_2D_ARRAY:
     73    case GL_TEXTURE_CUBE_MAP:
     74    case GL_TEXTURE_CUBE_MAP_ARRAY:
     75    case GL_TEXTURE_2D_MULTISAMPLE:
     76    case GL_TEXTURE_2D_MULTISAMPLE_ARRAY:
     77       ret_align = align_2d_yf[i];
     78       multiplier_ys = 4;
     79       break;
     80    case GL_TEXTURE_3D:
     81       ret_align = align_3d_yf[i];
     82       multiplier_ys = 4;
     83       break;
     84    default:
     85       unreachable("not reached");
     86    }
     87 
     88    if (mt->tr_mode == INTEL_MIPTREE_TRMODE_YS)
     89       ret_align *= multiplier_ys;
     90 
     91    assert(_mesa_is_pow_two(mt->num_samples));
     92 
     93    switch (mt->num_samples) {
     94    case 2:
     95    case 4:
     96       divisor = 2;
     97       break;
     98    case 8:
     99    case 16:
    100       divisor = 4;
    101       break;
    102    default:
    103       divisor = 1;
    104       break;
    105    }
    106    return ret_align / divisor;
    107 }
    108 
    109 
    110 static unsigned int
    111 intel_horizontal_texture_alignment_unit(struct brw_context *brw,
    112                                         struct intel_mipmap_tree *mt,
    113                                         uint32_t layout_flags)
    114 {
    115    if (layout_flags & MIPTREE_LAYOUT_FORCE_HALIGN16)
    116       return 16;
    117 
    118    /**
    119     * +----------------------------------------------------------------------+
    120     * |                                        | alignment unit width  ("i") |
    121     * | Surface Property                       |-----------------------------|
    122     * |                                        | 915 | 965 | ILK | SNB | IVB |
    123     * +----------------------------------------------------------------------+
    124     * | YUV 4:2:2 format                       |  8  |  4  |  4  |  4  |  4  |
    125     * | BC1-5 compressed format (DXTn/S3TC)    |  4  |  4  |  4  |  4  |  4  |
    126     * | FXT1  compressed format                |  8  |  8  |  8  |  8  |  8  |
    127     * | Depth Buffer (16-bit)                  |  4  |  4  |  4  |  4  |  8  |
    128     * | Depth Buffer (other)                   |  4  |  4  |  4  |  4  |  4  |
    129     * | Separate Stencil Buffer                | N/A | N/A |  8  |  8  |  8  |
    130     * | All Others                             |  4  |  4  |  4  |  4  |  4  |
    131     * +----------------------------------------------------------------------+
    132     *
    133     * On IVB+, non-special cases can be overridden by setting the SURFACE_STATE
    134     * "Surface Horizontal Alignment" field to HALIGN_4 or HALIGN_8.
    135     */
    136 
    137    if (brw->gen >= 7 && mt->format == MESA_FORMAT_Z_UNORM16)
    138       return 8;
    139 
    140    return 4;
    141 }
    142 
    143 static unsigned int
    144 tr_mode_vertical_texture_alignment(const struct intel_mipmap_tree *mt)
    145 {
    146    unsigned ret_align, divisor, multiplier_ys;
    147 
    148    /* Vertical alignment tables for TRMODE_YF */
    149    const unsigned align_2d_yf[] = {64, 32, 32, 16, 16};
    150    const unsigned align_3d_yf[] = {16, 16, 16, 8, 8};
    151 
    152    assert(mt->tr_mode != INTEL_MIPTREE_TRMODE_NONE);
    153 
    154    /* Alignment computations below assume a power of 2 cpp. */
    155    assert (mt->cpp >= 1 && mt->cpp <= 16 && _mesa_is_pow_two(mt->cpp)) ;
    156    /* Compute array index. */
    157    const int i = ffs(mt->cpp) - 1;
    158 
    159    switch(mt->target) {
    160    case GL_TEXTURE_2D:
    161    case GL_TEXTURE_RECTANGLE:
    162    case GL_TEXTURE_2D_ARRAY:
    163    case GL_TEXTURE_CUBE_MAP:
    164    case GL_TEXTURE_CUBE_MAP_ARRAY:
    165    case GL_TEXTURE_2D_MULTISAMPLE:
    166    case GL_TEXTURE_2D_MULTISAMPLE_ARRAY:
    167       ret_align = align_2d_yf[i];
    168       multiplier_ys = 4;
    169       break;
    170    case GL_TEXTURE_3D:
    171       ret_align = align_3d_yf[i];
    172       multiplier_ys = 2;
    173       break;
    174    case GL_TEXTURE_1D:
    175    case GL_TEXTURE_1D_ARRAY:
    176    default:
    177       unreachable("Unexpected miptree target");
    178    }
    179 
    180    if (mt->tr_mode == INTEL_MIPTREE_TRMODE_YS)
    181       ret_align *= multiplier_ys;
    182 
    183    assert(_mesa_is_pow_two(mt->num_samples));
    184 
    185    switch (mt->num_samples) {
    186    case 4:
    187    case 8:
    188       divisor = 2;
    189       break;
    190    case 16:
    191       divisor = 4;
    192       break;
    193    default:
    194       divisor = 1;
    195       break;
    196    }
    197    return ret_align / divisor;
    198 }
    199 
    200 static unsigned int
    201 intel_vertical_texture_alignment_unit(struct brw_context *brw,
    202                                       const struct intel_mipmap_tree *mt)
    203 {
    204    /**
    205     * +----------------------------------------------------------------------+
    206     * |                                        | alignment unit height ("j") |
    207     * | Surface Property                       |-----------------------------|
    208     * |                                        | 915 | 965 | ILK | SNB | IVB |
    209     * +----------------------------------------------------------------------+
    210     * | BC1-5 compressed format (DXTn/S3TC)    |  4  |  4  |  4  |  4  |  4  |
    211     * | FXT1  compressed format                |  4  |  4  |  4  |  4  |  4  |
    212     * | Depth Buffer                           |  2  |  2  |  2  |  4  |  4  |
    213     * | Separate Stencil Buffer                | N/A | N/A | N/A |  4  |  8  |
    214     * | Multisampled (4x or 8x) render target  | N/A | N/A | N/A |  4  |  4  |
    215     * | All Others                             |  2  |  2  |  2  |  *  |  *  |
    216     * +----------------------------------------------------------------------+
    217     *
    218     * Where "*" means either VALIGN_2 or VALIGN_4 depending on the setting of
    219     * the SURFACE_STATE "Surface Vertical Alignment" field.
    220     */
    221 
    222    /* Broadwell only supports VALIGN of 4, 8, and 16.  The BSpec says 4
    223     * should always be used, except for stencil buffers, which should be 8.
    224     */
    225    if (brw->gen >= 8)
    226       return 4;
    227 
    228    if (mt->num_samples > 1)
    229       return 4;
    230 
    231    GLenum base_format = _mesa_get_format_base_format(mt->format);
    232 
    233    if (brw->gen >= 6 &&
    234        (base_format == GL_DEPTH_COMPONENT ||
    235 	base_format == GL_DEPTH_STENCIL)) {
    236       return 4;
    237    }
    238 
    239    if (brw->gen == 7) {
    240       /* On Gen7, we prefer a vertical alignment of 4 when possible, because
    241        * that allows Y tiled render targets.
    242        *
    243        * From the Ivy Bridge PRM, Vol4 Part1 2.12.2.1 (SURFACE_STATE for most
    244        * messages), on p64, under the heading "Surface Vertical Alignment":
    245        *
    246        *     Value of 1 [VALIGN_4] is not supported for format YCRCB_NORMAL
    247        *     (0x182), YCRCB_SWAPUVY (0x183), YCRCB_SWAPUV (0x18f), YCRCB_SWAPY
    248        *     (0x190)
    249        *
    250        *     VALIGN_4 is not supported for surface format R32G32B32_FLOAT.
    251        */
    252       if (base_format == GL_YCBCR_MESA || mt->format == MESA_FORMAT_RGB_FLOAT32)
    253          return 2;
    254 
    255       return 4;
    256    }
    257 
    258    return 2;
    259 }
    260 
    261 static void
    262 gen9_miptree_layout_1d(struct intel_mipmap_tree *mt)
    263 {
    264    unsigned x = 0;
    265    unsigned width = mt->physical_width0;
    266    unsigned depth = mt->physical_depth0; /* number of array layers. */
    267 
    268    /* When this layout is used the horizontal alignment is fixed at 64 and the
    269     * hardware ignores the value given in the surface state
    270     */
    271    const unsigned int halign = 64;
    272 
    273    mt->total_height = mt->physical_height0;
    274    mt->total_width = 0;
    275 
    276    for (unsigned level = mt->first_level; level <= mt->last_level; level++) {
    277       unsigned img_width;
    278 
    279       intel_miptree_set_level_info(mt, level, x, 0, depth);
    280 
    281       img_width = ALIGN(width, halign);
    282 
    283       mt->total_width = MAX2(mt->total_width, x + img_width);
    284 
    285       x += img_width;
    286 
    287       width = minify(width, 1);
    288    }
    289 }
    290 
    291 static void
    292 brw_miptree_layout_2d(struct intel_mipmap_tree *mt)
    293 {
    294    unsigned x = 0;
    295    unsigned y = 0;
    296    unsigned width = mt->physical_width0;
    297    unsigned height = mt->physical_height0;
    298    unsigned depth = mt->physical_depth0; /* number of array layers. */
    299    unsigned int bw, bh;
    300 
    301    _mesa_get_format_block_size(mt->format, &bw, &bh);
    302 
    303    mt->total_width = mt->physical_width0;
    304 
    305    if (mt->compressed)
    306        mt->total_width = ALIGN_NPOT(mt->total_width, bw);
    307 
    308    /* May need to adjust width to accommodate the placement of
    309     * the 2nd mipmap.  This occurs when the alignment
    310     * constraints of mipmap placement push the right edge of the
    311     * 2nd mipmap out past the width of its parent.
    312     */
    313    if (mt->first_level != mt->last_level) {
    314        unsigned mip1_width;
    315 
    316        if (mt->compressed) {
    317           mip1_width = ALIGN_NPOT(minify(mt->physical_width0, 1), mt->halign) +
    318              ALIGN_NPOT(minify(mt->physical_width0, 2), bw);
    319        } else {
    320           mip1_width = ALIGN_NPOT(minify(mt->physical_width0, 1), mt->halign) +
    321              minify(mt->physical_width0, 2);
    322        }
    323 
    324        if (mip1_width > mt->total_width) {
    325            mt->total_width = mip1_width;
    326        }
    327    }
    328 
    329    mt->total_width /= bw;
    330    mt->total_height = 0;
    331 
    332    for (unsigned level = mt->first_level; level <= mt->last_level; level++) {
    333       unsigned img_height;
    334 
    335       intel_miptree_set_level_info(mt, level, x, y, depth);
    336 
    337       img_height = ALIGN_NPOT(height, mt->valign);
    338       if (mt->compressed)
    339 	 img_height /= bh;
    340 
    341       if (mt->array_layout == ALL_SLICES_AT_EACH_LOD) {
    342          /* Compact arrays with separated miplevels */
    343          img_height *= depth;
    344       }
    345 
    346       /* Because the images are packed better, the final offset
    347        * might not be the maximal one:
    348        */
    349       mt->total_height = MAX2(mt->total_height, y + img_height);
    350 
    351       /* Layout_below: step right after second mipmap.
    352        */
    353       if (level == mt->first_level + 1) {
    354 	 x += ALIGN_NPOT(width, mt->halign) / bw;
    355       } else {
    356 	 y += img_height;
    357       }
    358 
    359       width  = minify(width, 1);
    360       height = minify(height, 1);
    361 
    362       if (mt->target == GL_TEXTURE_3D)
    363          depth = minify(depth, 1);
    364    }
    365 }
    366 
    367 unsigned
    368 brw_miptree_get_horizontal_slice_pitch(const struct brw_context *brw,
    369                                        const struct intel_mipmap_tree *mt,
    370                                        unsigned level)
    371 {
    372    if ((brw->gen < 9 && mt->target == GL_TEXTURE_3D) ||
    373        (brw->gen == 4 && mt->target == GL_TEXTURE_CUBE_MAP)) {
    374       return ALIGN_NPOT(minify(mt->physical_width0, level), mt->halign);
    375    } else {
    376       return 0;
    377    }
    378 }
    379 
    380 unsigned
    381 brw_miptree_get_vertical_slice_pitch(const struct brw_context *brw,
    382                                      const struct intel_mipmap_tree *mt,
    383                                      unsigned level)
    384 {
    385    if (brw->gen >= 9) {
    386       /* ALL_SLICES_AT_EACH_LOD isn't supported on Gen8+ but this code will
    387        * effectively end up with a packed qpitch anyway whenever
    388        * mt->first_level == mt->last_level.
    389        */
    390       assert(mt->array_layout != ALL_SLICES_AT_EACH_LOD);
    391 
    392       /* On Gen9 we can pick whatever qpitch we like as long as it's aligned
    393        * to the vertical alignment so we don't need to add any extra rows.
    394        */
    395       unsigned qpitch = mt->total_height;
    396 
    397       /* If the surface might be used as a stencil buffer or HiZ buffer then
    398        * it needs to be a multiple of 8.
    399        */
    400       const GLenum base_format = _mesa_get_format_base_format(mt->format);
    401       if (_mesa_is_depth_or_stencil_format(base_format))
    402          qpitch = ALIGN(qpitch, 8);
    403 
    404       /* 3D textures need to be aligned to the tile height. At this point we
    405        * don't know which tiling will be used so let's just align it to 32
    406        */
    407       if (mt->target == GL_TEXTURE_3D)
    408          qpitch = ALIGN(qpitch, 32);
    409 
    410       return qpitch;
    411 
    412    } else if (mt->target == GL_TEXTURE_3D ||
    413               (brw->gen == 4 && mt->target == GL_TEXTURE_CUBE_MAP) ||
    414               mt->array_layout == ALL_SLICES_AT_EACH_LOD) {
    415       return ALIGN_NPOT(minify(mt->physical_height0, level), mt->valign);
    416 
    417    } else {
    418       const unsigned h0 = ALIGN_NPOT(mt->physical_height0, mt->valign);
    419       const unsigned h1 = ALIGN_NPOT(minify(mt->physical_height0, 1), mt->valign);
    420 
    421       return h0 + h1 + (brw->gen >= 7 ? 12 : 11) * mt->valign;
    422    }
    423 }
    424 
    425 static void
    426 align_cube(struct intel_mipmap_tree *mt)
    427 {
    428    /* The 965's sampler lays cachelines out according to how accesses
    429     * in the texture surfaces run, so they may be "vertical" through
    430     * memory.  As a result, the docs say in Surface Padding Requirements:
    431     * Sampling Engine Surfaces that two extra rows of padding are required.
    432     */
    433    if (mt->target == GL_TEXTURE_CUBE_MAP)
    434       mt->total_height += 2;
    435 }
    436 
    437 bool
    438 gen9_use_linear_1d_layout(const struct brw_context *brw,
    439                           const struct intel_mipmap_tree *mt)
    440 {
    441    /* On Gen9+ the mipmap levels of a 1D surface are all laid out in a
    442     * horizontal line. This isn't done for depth/stencil buffers however
    443     * because those will be using a tiled layout
    444     */
    445    if (brw->gen >= 9 &&
    446        (mt->target == GL_TEXTURE_1D ||
    447         mt->target == GL_TEXTURE_1D_ARRAY)) {
    448       GLenum base_format = _mesa_get_format_base_format(mt->format);
    449 
    450       if (base_format != GL_DEPTH_COMPONENT &&
    451           base_format != GL_DEPTH_STENCIL &&
    452           base_format != GL_STENCIL_INDEX)
    453          return true;
    454    }
    455 
    456    return false;
    457 }
    458 
    459 static void
    460 brw_miptree_layout_texture_array(struct brw_context *brw,
    461 				 struct intel_mipmap_tree *mt)
    462 {
    463    unsigned height = mt->physical_height0;
    464    bool layout_1d = gen9_use_linear_1d_layout(brw, mt);
    465    int physical_qpitch;
    466 
    467    if (layout_1d)
    468       gen9_miptree_layout_1d(mt);
    469    else
    470       brw_miptree_layout_2d(mt);
    471 
    472    if (layout_1d) {
    473       physical_qpitch = 1;
    474       /* When using the horizontal layout the qpitch specifies the distance in
    475        * pixels between array slices. The total_width is forced to be a
    476        * multiple of the horizontal alignment in brw_miptree_layout_1d (in
    477        * this case it's always 64). The vertical alignment is ignored.
    478        */
    479       mt->qpitch = mt->total_width;
    480    } else {
    481       mt->qpitch = brw_miptree_get_vertical_slice_pitch(brw, mt, 0);
    482       /* Unlike previous generations the qpitch is a multiple of the
    483        * compressed block size on Gen9 so physical_qpitch matches mt->qpitch.
    484        */
    485       physical_qpitch = (mt->compressed && brw->gen < 9 ? mt->qpitch / 4 :
    486                          mt->qpitch);
    487    }
    488 
    489    for (unsigned level = mt->first_level; level <= mt->last_level; level++) {
    490       unsigned img_height;
    491       img_height = ALIGN_NPOT(height, mt->valign);
    492       if (mt->compressed)
    493          img_height /= mt->valign;
    494 
    495       for (unsigned q = 0; q < mt->level[level].depth; q++) {
    496          if (mt->array_layout == ALL_SLICES_AT_EACH_LOD) {
    497             intel_miptree_set_image_offset(mt, level, q, 0, q * img_height);
    498          } else {
    499             intel_miptree_set_image_offset(mt, level, q, 0, q * physical_qpitch);
    500          }
    501       }
    502       height = minify(height, 1);
    503    }
    504    if (mt->array_layout == ALL_LOD_IN_EACH_SLICE)
    505       mt->total_height = physical_qpitch * mt->physical_depth0;
    506 
    507    align_cube(mt);
    508 }
    509 
    510 static void
    511 brw_miptree_layout_texture_3d(struct brw_context *brw,
    512                               struct intel_mipmap_tree *mt)
    513 {
    514    mt->total_width = 0;
    515    mt->total_height = 0;
    516 
    517    unsigned ysum = 0;
    518    unsigned bh, bw;
    519 
    520    _mesa_get_format_block_size(mt->format, &bw, &bh);
    521 
    522    for (unsigned level = mt->first_level; level <= mt->last_level; level++) {
    523       unsigned WL = MAX2(mt->physical_width0 >> level, 1);
    524       unsigned HL = MAX2(mt->physical_height0 >> level, 1);
    525       unsigned DL = MAX2(mt->physical_depth0 >> level, 1);
    526       unsigned wL = ALIGN_NPOT(WL, mt->halign);
    527       unsigned hL = ALIGN_NPOT(HL, mt->valign);
    528 
    529       if (mt->target == GL_TEXTURE_CUBE_MAP)
    530          DL = 6;
    531 
    532       intel_miptree_set_level_info(mt, level, 0, 0, DL);
    533 
    534       for (unsigned q = 0; q < DL; q++) {
    535          unsigned x = (q % (1 << level)) * wL;
    536          unsigned y = ysum + (q >> level) * hL;
    537 
    538          intel_miptree_set_image_offset(mt, level, q, x / bw, y / bh);
    539          mt->total_width = MAX2(mt->total_width, (x + wL) / bw);
    540          mt->total_height = MAX2(mt->total_height, (y + hL) / bh);
    541       }
    542 
    543       ysum += ALIGN(DL, 1 << level) / (1 << level) * hL;
    544    }
    545 
    546    align_cube(mt);
    547 }
    548 
    549 /**
    550  * \brief Helper function for intel_miptree_create().
    551  */
    552 static uint32_t
    553 brw_miptree_choose_tiling(struct brw_context *brw,
    554                           const struct intel_mipmap_tree *mt,
    555                           uint32_t layout_flags)
    556 {
    557    if (mt->format == MESA_FORMAT_S_UINT8) {
    558       /* The stencil buffer is W tiled. However, we request from the kernel a
    559        * non-tiled buffer because the GTT is incapable of W fencing.
    560        */
    561       return I915_TILING_NONE;
    562    }
    563 
    564    /* Do not support changing the tiling for miptrees with pre-allocated BOs. */
    565    assert((layout_flags & MIPTREE_LAYOUT_FOR_BO) == 0);
    566 
    567    /* Some usages may want only one type of tiling, like depth miptrees (Y
    568     * tiled), or temporary BOs for uploading data once (linear).
    569     */
    570    switch (layout_flags & MIPTREE_LAYOUT_TILING_ANY) {
    571    case MIPTREE_LAYOUT_TILING_ANY:
    572       break;
    573    case MIPTREE_LAYOUT_TILING_Y:
    574       return I915_TILING_Y;
    575    case MIPTREE_LAYOUT_TILING_NONE:
    576       return I915_TILING_NONE;
    577    }
    578 
    579    if (mt->num_samples > 1) {
    580       /* From p82 of the Sandy Bridge PRM, dw3[1] of SURFACE_STATE ("Tiled
    581        * Surface"):
    582        *
    583        *   [DevSNB+]: For multi-sample render targets, this field must be
    584        *   1. MSRTs can only be tiled.
    585        *
    586        * Our usual reason for preferring X tiling (fast blits using the
    587        * blitting engine) doesn't apply to MSAA, since we'll generally be
    588        * downsampling or upsampling when blitting between the MSAA buffer
    589        * and another buffer, and the blitting engine doesn't support that.
    590        * So use Y tiling, since it makes better use of the cache.
    591        */
    592       return I915_TILING_Y;
    593    }
    594 
    595    GLenum base_format = _mesa_get_format_base_format(mt->format);
    596    if (base_format == GL_DEPTH_COMPONENT ||
    597        base_format == GL_DEPTH_STENCIL_EXT)
    598       return I915_TILING_Y;
    599 
    600    /* 1D textures (and 1D array textures) don't get any benefit from tiling,
    601     * in fact it leads to a less efficient use of memory space and bandwidth
    602     * due to tile alignment.
    603     */
    604    if (mt->logical_height0 == 1)
    605       return I915_TILING_NONE;
    606 
    607    int minimum_pitch = mt->total_width * mt->cpp;
    608 
    609    /* If the width is much smaller than a tile, don't bother tiling. */
    610    if (minimum_pitch < 64)
    611       return I915_TILING_NONE;
    612 
    613    if (ALIGN(minimum_pitch, 512) >= 32768) {
    614       perf_debug("%dx%d miptree too large to blit, falling back to untiled",
    615                  mt->total_width, mt->total_height);
    616       return I915_TILING_NONE;
    617    }
    618 
    619    /* Pre-gen6 doesn't have BLORP to handle Y-tiling, so use X-tiling. */
    620    if (brw->gen < 6)
    621       return I915_TILING_X;
    622 
    623    /* From the Sandybridge PRM, Volume 1, Part 2, page 32:
    624     * "NOTE: 128BPE Format Color Buffer ( render target ) MUST be either TileX
    625     *  or Linear."
    626     * 128 bits per pixel translates to 16 bytes per pixel. This is necessary
    627     * all the way back to 965, but is permitted on Gen7+.
    628     */
    629    if (brw->gen < 7 && mt->cpp >= 16)
    630       return I915_TILING_X;
    631 
    632    /* From the Ivy Bridge PRM, Vol4 Part1 2.12.2.1 (SURFACE_STATE for most
    633     * messages), on p64, under the heading "Surface Vertical Alignment":
    634     *
    635     *     This field must be set to VALIGN_4 for all tiled Y Render Target
    636     *     surfaces.
    637     *
    638     * So if the surface is renderable and uses a vertical alignment of 2,
    639     * force it to be X tiled.  This is somewhat conservative (it's possible
    640     * that the client won't ever render to this surface), but it's difficult
    641     * to know that ahead of time.  And besides, since we use a vertical
    642     * alignment of 4 as often as we can, this shouldn't happen very often.
    643     */
    644    if (brw->gen == 7 && mt->valign == 2 &&
    645        brw->format_supported_as_render_target[mt->format]) {
    646       return I915_TILING_X;
    647    }
    648 
    649    return I915_TILING_Y | I915_TILING_X;
    650 }
    651 
    652 static void
    653 intel_miptree_set_total_width_height(struct brw_context *brw,
    654                                      struct intel_mipmap_tree *mt)
    655 {
    656    switch (mt->target) {
    657    case GL_TEXTURE_CUBE_MAP:
    658       if (brw->gen == 4) {
    659          /* Gen4 stores cube maps as 3D textures. */
    660          assert(mt->physical_depth0 == 6);
    661          brw_miptree_layout_texture_3d(brw, mt);
    662       } else {
    663          /* All other hardware stores cube maps as 2D arrays. */
    664 	 brw_miptree_layout_texture_array(brw, mt);
    665       }
    666       break;
    667 
    668    case GL_TEXTURE_3D:
    669       if (brw->gen >= 9)
    670          brw_miptree_layout_texture_array(brw, mt);
    671       else
    672          brw_miptree_layout_texture_3d(brw, mt);
    673       break;
    674 
    675    case GL_TEXTURE_1D_ARRAY:
    676    case GL_TEXTURE_2D_ARRAY:
    677    case GL_TEXTURE_2D_MULTISAMPLE_ARRAY:
    678    case GL_TEXTURE_CUBE_MAP_ARRAY:
    679       brw_miptree_layout_texture_array(brw, mt);
    680       break;
    681 
    682    default:
    683       switch (mt->msaa_layout) {
    684       case INTEL_MSAA_LAYOUT_UMS:
    685       case INTEL_MSAA_LAYOUT_CMS:
    686          brw_miptree_layout_texture_array(brw, mt);
    687          break;
    688       case INTEL_MSAA_LAYOUT_NONE:
    689       case INTEL_MSAA_LAYOUT_IMS:
    690          if (gen9_use_linear_1d_layout(brw, mt))
    691             gen9_miptree_layout_1d(mt);
    692          else
    693             brw_miptree_layout_2d(mt);
    694          break;
    695       }
    696       break;
    697    }
    698 
    699    DBG("%s: %dx%dx%d\n", __func__,
    700        mt->total_width, mt->total_height, mt->cpp);
    701 }
    702 
    703 static void
    704 intel_miptree_set_alignment(struct brw_context *brw,
    705                             struct intel_mipmap_tree *mt,
    706                             uint32_t layout_flags)
    707 {
    708    /**
    709     * From the "Alignment Unit Size" section of various specs, namely:
    710     * - Gen3 Spec: "Memory Data Formats" Volume,         Section 1.20.1.4
    711     * - i965 and G45 PRMs:             Volume 1,         Section 6.17.3.4.
    712     * - Ironlake and Sandybridge PRMs: Volume 1, Part 1, Section 7.18.3.4
    713     * - BSpec (for Ivybridge and slight variations in separate stencil)
    714     */
    715    bool gen6_hiz_or_stencil = false;
    716 
    717    if (brw->gen == 6 && mt->array_layout == ALL_SLICES_AT_EACH_LOD) {
    718       const GLenum base_format = _mesa_get_format_base_format(mt->format);
    719       gen6_hiz_or_stencil = _mesa_is_depth_or_stencil_format(base_format);
    720    }
    721 
    722    if (gen6_hiz_or_stencil) {
    723       /* On gen6, we use ALL_SLICES_AT_EACH_LOD for stencil/hiz because the
    724        * hardware doesn't support multiple mip levels on stencil/hiz.
    725        *
    726        * PRM Vol 2, Part 1, 7.5.3 Hierarchical Depth Buffer:
    727        * "The hierarchical depth buffer does not support the LOD field"
    728        *
    729        * PRM Vol 2, Part 1, 7.5.4.1 Separate Stencil Buffer:
    730        * "The stencil depth buffer does not support the LOD field"
    731        */
    732       if (mt->format == MESA_FORMAT_S_UINT8) {
    733          /* Stencil uses W tiling, so we force W tiling alignment for the
    734           * ALL_SLICES_AT_EACH_LOD miptree layout.
    735           */
    736          mt->halign = 64;
    737          mt->valign = 64;
    738          assert((layout_flags & MIPTREE_LAYOUT_FORCE_HALIGN16) == 0);
    739       } else {
    740          /* Depth uses Y tiling, so we force need Y tiling alignment for the
    741           * ALL_SLICES_AT_EACH_LOD miptree layout.
    742           */
    743          mt->halign = 128 / mt->cpp;
    744          mt->valign = 32;
    745       }
    746    } else if (mt->compressed) {
    747        /* The hardware alignment requirements for compressed textures
    748         * happen to match the block boundaries.
    749         */
    750       _mesa_get_format_block_size(mt->format, &mt->halign, &mt->valign);
    751 
    752       /* On Gen9+ we can pick our own alignment for compressed textures but it
    753        * has to be a multiple of the block size. The minimum alignment we can
    754        * pick is 4 so we effectively have to align to 4 times the block
    755        * size
    756        */
    757       if (brw->gen >= 9) {
    758          mt->halign *= 4;
    759          mt->valign *= 4;
    760       }
    761    } else if (mt->format == MESA_FORMAT_S_UINT8) {
    762       mt->halign = 8;
    763       mt->valign = brw->gen >= 7 ? 8 : 4;
    764    } else if (brw->gen >= 9 && mt->tr_mode != INTEL_MIPTREE_TRMODE_NONE) {
    765       mt->halign = tr_mode_horizontal_texture_alignment(mt);
    766       mt->valign = tr_mode_vertical_texture_alignment(mt);
    767    } else {
    768       mt->halign =
    769          intel_horizontal_texture_alignment_unit(brw, mt, layout_flags);
    770       mt->valign = intel_vertical_texture_alignment_unit(brw, mt);
    771    }
    772 }
    773 
    774 void
    775 brw_miptree_layout(struct brw_context *brw,
    776                    struct intel_mipmap_tree *mt,
    777                    uint32_t layout_flags)
    778 {
    779    mt->tr_mode = INTEL_MIPTREE_TRMODE_NONE;
    780 
    781    intel_miptree_set_alignment(brw, mt, layout_flags);
    782    intel_miptree_set_total_width_height(brw, mt);
    783 
    784    if (!mt->total_width || !mt->total_height) {
    785       intel_miptree_release(&mt);
    786       return;
    787    }
    788 
    789    /* On Gen9+ the alignment values are expressed in multiples of the block
    790     * size
    791     */
    792    if (brw->gen >= 9) {
    793       unsigned int i, j;
    794       _mesa_get_format_block_size(mt->format, &i, &j);
    795       mt->halign /= i;
    796       mt->valign /= j;
    797    }
    798 
    799    if ((layout_flags & MIPTREE_LAYOUT_FOR_BO) == 0)
    800       mt->tiling = brw_miptree_choose_tiling(brw, mt, layout_flags);
    801 }
    802 
    803