/*
 * Copyright 2015 Intel Corporation
 *
 *  Permission is hereby granted, free of charge, to any person obtaining a
 *  copy of this software and associated documentation files (the "Software"),
 *  to deal in the Software without restriction, including without limitation
 *  the rights to use, copy, modify, merge, publish, distribute, sublicense,
 *  and/or sell copies of the Software, and to permit persons to whom the
 *  Software is furnished to do so, subject to the following conditions:
 *
 *  The above copyright notice and this permission notice (including the next
 *  paragraph) shall be included in all copies or substantial portions of the
 *  Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 *  THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 *  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 *  IN THE SOFTWARE.
 */

#include "isl_gen8.h"
#include "isl_gen9.h"
#include "isl_priv.h"

/**
 * Calculate the surface's subimage alignment, in units of surface samples,
 * for the standard tiling formats Yf and Ys.
 */
static void
gen9_calc_std_image_alignment_sa(const struct isl_device *dev,
                                 const struct isl_surf_init_info *restrict info,
                                 enum isl_tiling tiling,
                                 enum isl_msaa_layout msaa_layout,
                                 struct isl_extent3d *align_sa)
{
   const struct isl_format_layout *fmtl = isl_format_get_layout(info->format);

   assert(isl_tiling_is_std_y(tiling));

   const uint32_t bpb = fmtl->bpb;
   const uint32_t is_Ys = tiling == ISL_TILING_Ys;

   switch (info->dim) {
   case ISL_SURF_DIM_1D:
      /* See the Skylake BSpec > Memory Views > Common Surface Formats > Surface
       * Layout and Tiling > 1D Surfaces > 1D Alignment Requirements.
       */
      *align_sa = (struct isl_extent3d) {
         .w = 1 << (12 - (ffs(bpb) - 4) + (4 * is_Ys)),
         .h = 1,
         .d = 1,
      };
      return;
   case ISL_SURF_DIM_2D:
      /* See the Skylake BSpec > Memory Views > Common Surface Formats >
       * Surface Layout and Tiling > 2D Surfaces > 2D/CUBE Alignment
       * Requirements.
       */
      *align_sa = (struct isl_extent3d) {
         .w = 1 << (6 - ((ffs(bpb) - 4) / 2) + (4 * is_Ys)),
         .h = 1 << (6 - ((ffs(bpb) - 3) / 2) + (4 * is_Ys)),
         .d = 1,
      };

      if (is_Ys) {
         /* FINISHME(chadv): I don't trust this code. Untested. */
         isl_finishme("%s:%s: [SKL+] multisample TileYs", __FILE__, __func__);

         switch (msaa_layout) {
         case ISL_MSAA_LAYOUT_NONE:
         case ISL_MSAA_LAYOUT_INTERLEAVED:
            break;
         case ISL_MSAA_LAYOUT_ARRAY:
            align_sa->w >>= (ffs(info->samples) - 0) / 2;
            align_sa->h >>= (ffs(info->samples) - 1) / 2;
            break;
         }
      }
      return;

   case ISL_SURF_DIM_3D:
      /* See the Skylake BSpec > Memory Views > Common Surface Formats > Surface
       * Layout and Tiling > 1D Surfaces > 1D Alignment Requirements.
       */
      *align_sa = (struct isl_extent3d) {
         .w = 1 << (4 - ((ffs(bpb) - 2) / 3) + (4 * is_Ys)),
         .h = 1 << (4 - ((ffs(bpb) - 4) / 3) + (2 * is_Ys)),
         .d = 1 << (4 - ((ffs(bpb) - 3) / 3) + (2 * is_Ys)),
      };
      return;
   }

   unreachable("bad isl_surface_type");
}

void
gen9_choose_image_alignment_el(const struct isl_device *dev,
                               const struct isl_surf_init_info *restrict info,
                               enum isl_tiling tiling,
                               enum isl_msaa_layout msaa_layout,
                               struct isl_extent3d *image_align_el)
{
   /* Handled by isl_choose_image_alignment_el */
   assert(info->format != ISL_FORMAT_HIZ);

   /* This BSpec text provides some insight into the hardware's alignment
    * requirements [Skylake BSpec > Memory Views > Common Surface Formats >
    * Surface Layout and Tiling > 2D Surfaces]:
    *
    *    An LOD must be aligned to a cache-line except for some special cases
    *    related to Planar YUV surfaces.  In general, the cache-alignment
    *    restriction implies there is a minimum height for an LOD of 4 texels.
    *    So, LODs which are smaller than 4 high are padded.
    *
    * From the Skylake BSpec, RENDER_SURFACE_STATE Surface Vertical Alignment:
    *
    *    - For Sampling Engine and Render Target Surfaces: This field
    *      specifies the vertical alignment requirement in elements for the
    *      surface. [...] An element is defined as a pixel in uncompresed
    *      surface formats, and as a compression block in compressed surface
    *      formats. For MSFMT_DEPTH_STENCIL type multisampled surfaces, an
    *      element is a sample.
    *
    *    - This field is used for 2D, CUBE, and 3D surface alignment when Tiled
    *      Resource Mode is TRMODE_NONE (Tiled Resource Mode is disabled).
    *      This field is ignored for 1D surfaces and also when Tiled Resource
    *      Mode is not TRMODE_NONE (e.g. Tiled Resource Mode is enabled).
    *
    *      See the appropriate Alignment  table in the "Surface Layout and
    *      Tiling" section under Common Surface Formats for the table of
    *      alignment values for Tiled Resrouces.
    *
    *    - For uncompressed surfaces, the units of "j" are rows of pixels on
    *      the physical surface. For compressed texture formats, the units of
    *      "j" are in compression blocks, thus each increment in "j" is equal
    *      to h pixels, where h is the height of the compression block in
    *      pixels.
    *
    *    - Valid Values: VALIGN_4, VALIGN_8, VALIGN_16
    *
    * From the Skylake BSpec, RENDER_SURFACE_STATE Surface Horizontal
    * Alignment:
    *
    *    -  For uncompressed surfaces, the units of "i" are pixels on the
    *       physical surface. For compressed texture formats, the units of "i"
    *       are in compression blocks, thus each increment in "i" is equal to
    *       w pixels, where w is the width of the compression block in pixels.
    *
    *    - Valid Values: HALIGN_4, HALIGN_8, HALIGN_16
    */

   if (isl_tiling_is_std_y(tiling)) {
      struct isl_extent3d image_align_sa;
      gen9_calc_std_image_alignment_sa(dev, info, tiling, msaa_layout,
                                     &image_align_sa);

      *image_align_el = isl_extent3d_sa_to_el(info->format, image_align_sa);
      return;
   }

   if (info->dim == ISL_SURF_DIM_1D) {
      /* See the Skylake BSpec > Memory Views > Common Surface Formats > Surface
       * Layout and Tiling > 1D Surfaces > 1D Alignment Requirements.
       */
      *image_align_el = isl_extent3d(64, 1, 1);
      return;
   }

   if (isl_format_is_compressed(info->format)) {
      /* On Gen9, the meaning of RENDER_SURFACE_STATE's
       * SurfaceHorizontalAlignment and SurfaceVerticalAlignment changed for
       * compressed formats. They now indicate a multiple of the compression
       * block.  For example, if the compression mode is ETC2 then HALIGN_4
       * indicates a horizontal alignment of 16 pixels.
       *
       * To avoid wasting memory, choose the smallest alignment possible:
       * HALIGN_4 and VALIGN_4.
       */
      *image_align_el = isl_extent3d(4, 4, 1);
      return;
   }

   gen8_choose_image_alignment_el(dev, info, tiling, msaa_layout,
                                  image_align_el);
}