pan_encoder.h

/*
 * Copyright (C) 2019 Collabora, Ltd.
 *
 * 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.
 *
 * Authors (Collabora):
 *   Alyssa Rosenzweig <[email protected]>
 */

#ifndef __PAN_ENCODER_H
#define __PAN_ENCODER_H

#include <stdbool.h>
#include "util/format/u_format.h"
#include "pan_bo.h"
#include "midgard_pack.h"

/* Indices for named (non-XFB) varyings that are present. These are packed
 * tightly so they correspond to a bitfield present (P) indexed by (1 <<
 * PAN_VARY_*). This has the nice property that you can lookup the buffer index
 * of a given special field given a shift S by:
 *
 *      idx = popcount(P & ((1 << S) - 1))
 *
 * That is... look at all of the varyings that come earlier and count them, the
 * count is the new index since plus one. Likewise, the total number of special
 * buffers required is simply popcount(P)
 */

enum pan_special_varying {
        PAN_VARY_GENERAL = 0,
        PAN_VARY_POSITION = 1,
        PAN_VARY_PSIZ = 2,
        PAN_VARY_PNTCOORD = 3,
        PAN_VARY_FACE = 4,
        PAN_VARY_FRAGCOORD = 5,

        /* Keep last */
        PAN_VARY_MAX,
};

/* Tiler structure size computation */

struct panfrost_device;

unsigned
panfrost_tiler_get_polygon_list_size(const struct panfrost_device *dev,
                                     unsigned fb_width, unsigned fb_height,
                                     bool has_draws);

unsigned
panfrost_tiler_header_size(unsigned width, unsigned height, unsigned mask, bool hierarchy);

unsigned
panfrost_tiler_full_size(unsigned width, unsigned height, unsigned mask, bool hierarchy);

unsigned
panfrost_choose_hierarchy_mask(
        unsigned width, unsigned height,
        unsigned vertex_count, bool hierarchy);

/* Stack sizes */

unsigned
panfrost_get_stack_shift(unsigned stack_size);

unsigned
panfrost_get_total_stack_size(
                unsigned thread_size,
                unsigned threads_per_core,
                unsigned core_count);

const char * panfrost_model_name(unsigned gpu_id);

/* Attributes / instancing */

unsigned
panfrost_padded_vertex_count(unsigned vertex_count);

unsigned
panfrost_compute_magic_divisor(unsigned hw_divisor, unsigned *o_shift, unsigned *extra_flags);

/* Records for gl_VertexID and gl_InstanceID use special encodings on Midgard */

static inline void
panfrost_vertex_id(unsigned padded_count,
                   struct mali_attribute_buffer_packed *attr,
                   bool instanced)
{
        pan_pack(attr, ATTRIBUTE_VERTEX_ID, cfg) {
                if (instanced) {
                        cfg.divisor_r = __builtin_ctz(padded_count);
                        cfg.divisor_p = padded_count >> (cfg.divisor_r + 1);
                } else {
                        /* Large values so the modulo is a no-op */
                        cfg.divisor_r = 0x1F;
                        cfg.divisor_p = 0x4;
                }
        }
}

static inline void
panfrost_instance_id(unsigned padded_count,
                     struct mali_attribute_buffer_packed *attr,
                     bool instanced)
{
        pan_pack(attr, ATTRIBUTE_INSTANCE_ID, cfg) {
                if (!instanced || padded_count <= 1) {
                        /* Divide by large number to force to 0 */
                        cfg.divisor_p = ((1u << 31) - 1);
                        cfg.divisor_r = 0x1F;
                        cfg.divisor_e = 0x1;
                } else if(util_is_power_of_two_or_zero(padded_count)) {
                        /* Can't underflow since padded_count >= 2 */
                        cfg.divisor_r = __builtin_ctz(padded_count) - 1;
                } else {
                        cfg.divisor_p =
                                panfrost_compute_magic_divisor(padded_count,
                                        &cfg.divisor_r, &cfg.divisor_e);
                }
        }
}

/* Sampler comparison functions are flipped in OpenGL from the hardware, so we
 * need to be able to flip accordingly */

static inline enum mali_func
panfrost_flip_compare_func(enum mali_func f)
{
        switch (f) {
        case MALI_FUNC_LESS: return MALI_FUNC_GREATER;
        case MALI_FUNC_GREATER: return MALI_FUNC_LESS;
        case MALI_FUNC_LEQUAL: return MALI_FUNC_GEQUAL;
        case MALI_FUNC_GEQUAL: return MALI_FUNC_LEQUAL;
        default: return f;
        }

}

/* Compute shaders are invoked with a gl_NumWorkGroups X/Y/Z triplet. Vertex
 * shaders are invoked as (1, vertex_count, instance_count). Compute shaders
 * also have a gl_WorkGroupSize X/Y/Z triplet. These 6 values are packed
 * together in a dynamic bitfield, packed by this routine. */

static inline void
panfrost_pack_work_groups_compute(
        struct mali_invocation_packed *out,
        unsigned num_x, unsigned num_y, unsigned num_z,
        unsigned size_x, unsigned size_y, unsigned size_z,
        bool quirk_graphics, bool indirect_dispatch)
{
        /* The values needing packing, in order, and the corresponding shifts.
         * Indicies into shift are off-by-one to make the logic easier */

        unsigned values[6] = { size_x, size_y, size_z, num_x, num_y, num_z };
        unsigned shifts[7] = { 0 };
        uint32_t packed = 0;

        for (unsigned i = 0; i < 6; ++i) {
                /* Must be positive, otherwise we underflow */
                assert(values[i] >= 1);

                /* OR it in, shifting as required */
                packed |= ((values[i] - 1) << shifts[i]);

                /* How many bits did we use? */
                unsigned bit_count = util_logbase2_ceil(values[i]);

                /* Set the next shift accordingly */
                shifts[i + 1] = shifts[i] + bit_count;
        }

        pan_pack(out, INVOCATION, cfg) {
                cfg.invocations = packed;
                cfg.size_y_shift = shifts[1];
                cfg.size_z_shift = shifts[2];
                cfg.workgroups_x_shift = shifts[3];

                if (!indirect_dispatch) {
                        /* Leave zero for the dispatch shader */
                        cfg.workgroups_y_shift = shifts[4];
                        cfg.workgroups_z_shift = shifts[5];
                }

                /* Quirk: for non-instanced graphics, the blob sets
                 * workgroups_z_shift = 32. This doesn't appear to matter to
                 * the hardware, but it's good to be bit-identical. */

                if (quirk_graphics && (num_z <= 1))
                        cfg.workgroups_z_shift = 32;

                /* For graphics, set to the minimum efficient value. For
                 * compute, must equal the workgroup X shift for barriers to
                 * function correctly */

                cfg.thread_group_split = quirk_graphics ?
                        MALI_SPLIT_MIN_EFFICIENT : cfg.workgroups_x_shift;
        }
}

/* Format conversion */
static inline enum mali_z_internal_format
panfrost_get_z_internal_format(enum pipe_format fmt)
{
         switch (fmt) {
         case PIPE_FORMAT_Z16_UNORM:
         case PIPE_FORMAT_Z16_UNORM_S8_UINT:
                return MALI_Z_INTERNAL_FORMAT_D16;
         case PIPE_FORMAT_Z24_UNORM_S8_UINT:
         case PIPE_FORMAT_Z24X8_UNORM:
                return MALI_Z_INTERNAL_FORMAT_D24;
         case PIPE_FORMAT_Z32_FLOAT:
         case PIPE_FORMAT_Z32_FLOAT_S8X24_UINT:
                return MALI_Z_INTERNAL_FORMAT_D32;
         default:
                unreachable("Unsupported depth/stencil format.");
         }
}

#endif