src/gallium/drivers/panfrost/pan_blend_cso.c - platform/external/mesa3d - Git at Google

 /*
  * 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 <alyssa.rosenzweig@collabora.com>
  *
  */

 #include <stdio.h>
 #include "util/u_memory.h"
 #include "pan_blend_shaders.h"
 #include "pan_blending.h"
 #include "pan_bo.h"
 #include "panfrost-quirks.h"

 /* A given Gallium blend state can be encoded to the hardware in numerous,
  * dramatically divergent ways due to the interactions of blending with
  * framebuffer formats. Conceptually, there are two modes:
  *
  * - Fixed-function blending (for suitable framebuffer formats, suitable blend
  *   state, and suitable blend constant)
  *
  * - Blend shaders (for everything else)
  *
  * A given Gallium blend configuration will compile to exactly one
  * fixed-function blend state, if it compiles to any, although the constant
  * will vary across runs as that is tracked outside of the Gallium CSO.
  *
  * However, that same blend configuration will compile to many different blend
  * shaders, depending on the framebuffer formats active. The rationale is that
  * blend shaders override not just fixed-function blending but also
  * fixed-function format conversion. As such, each blend shader must be
  * hardcoded to a particular framebuffer format to correctly pack/unpack it. As
  * a concrete example, to the hardware there is no difference (!) between RG16F
  * and RG16UI -- both are simply 4-byte-per-pixel chunks. Thus both formats
  * require a blend shader (even with blending is totally disabled!), required
  * to do conversion as necessary (if necessary).
  *
  * All of this state is encapsulated in the panfrost_blend_state struct
  * (our subclass of pipe_blend_state).
  */

 /* Given an initialized CSO and a particular framebuffer format, grab a
  * blend shader, generating and compiling it if it doesn't exist
  * (lazy-loading in a way). This routine, when the cache hits, should
  * befast, suitable for calling every draw to avoid wacky dirty
  * tracking paths. If the cache hits, boom, done. */

 struct panfrost_blend_shader *
 panfrost_get_blend_shader(
         struct panfrost_context *ctx,
         struct panfrost_blend_state *blend,
         enum pipe_format fmt,
         unsigned rt)
 {
         /* Prevent NULL collision issues.. */
         assert(fmt != 0);

         /* Check the cache. Key by the RT and format */
         struct hash_table_u64 *shaders = blend->rt[rt].shaders;
         unsigned key = (fmt << 3) | rt;

         struct panfrost_blend_shader *shader =
                 _mesa_hash_table_u64_search(shaders, key);

         if (shader)
                 return shader;

         /* Cache miss. Build one instead, cache it, and go */

         struct panfrost_blend_shader generated =
                 panfrost_compile_blend_shader(ctx, &blend->base, fmt, rt);

         shader = mem_dup(&generated, sizeof(generated));
         _mesa_hash_table_u64_insert(shaders, key, shader);
         return  shader;
 }

 /* Create a blend CSO. Essentially, try to compile a fixed-function
  * expression and initialize blend shaders */

 static void *
 panfrost_create_blend_state(struct pipe_context *pipe,
                             const struct pipe_blend_state *blend)
 {
         struct panfrost_context *ctx = pan_context(pipe);
         struct panfrost_blend_state *so = rzalloc(ctx, struct panfrost_blend_state);
         so->base = *blend;

         /* TODO: The following features are not yet implemented */
         assert(!blend->alpha_to_one);

         for (unsigned c = 0; c < PIPE_MAX_COLOR_BUFS; ++c) {
                 struct panfrost_blend_rt *rt = &so->rt[c];

                 /* There are two paths. First, we would like to try a
                  * fixed-function if we can */

                 /* Without indep blending, the first RT settings replicate */

                 if (!blend->logicop_enable) {
                         unsigned g =
                                 blend->independent_blend_enable ? c : 0;

                         rt->has_fixed_function =
                                 panfrost_make_fixed_blend_mode(
                                         &blend->rt[g],
                                         &rt->equation,
                                         &rt->constant_mask,
                                         blend->rt[g].colormask);
                 }

                 /* Regardless if that works, we also need to initialize
                  * the blend shaders */

                 rt->shaders = _mesa_hash_table_u64_create(so);
         }

         return so;
 }

 static void
 panfrost_bind_blend_state(struct pipe_context *pipe,
                           void *cso)
 {
         struct panfrost_context *ctx = pan_context(pipe);
         struct pipe_blend_state *blend = (struct pipe_blend_state *) cso;
         struct panfrost_blend_state *pblend = (struct panfrost_blend_state *) cso;
         ctx->blend = pblend;

         if (!blend)
                 return;
 }

 static void
 panfrost_delete_blend_shader(struct hash_entry *entry)
 {
         struct panfrost_blend_shader *shader = (struct panfrost_blend_shader *)entry->data;
         free(shader->buffer);
         free(shader);
 }

 static void
 panfrost_delete_blend_state(struct pipe_context *pipe,
                             void *cso)
 {
         struct panfrost_blend_state *blend = (struct panfrost_blend_state *) cso;

         for (unsigned c = 0; c < PIPE_MAX_COLOR_BUFS; ++c) {
                 struct panfrost_blend_rt *rt = &blend->rt[c];
                 _mesa_hash_table_u64_clear(rt->shaders, panfrost_delete_blend_shader);
         }
         ralloc_free(blend);
 }

 static void
 panfrost_set_blend_color(struct pipe_context *pipe,
                          const struct pipe_blend_color *blend_color)
 {
         struct panfrost_context *ctx = pan_context(pipe);

         if (blend_color)
                 ctx->blend_color = *blend_color;
 }

 /* Given a vec4 of constants, reduce it to just a single constant according to
  * the mask (if we can) */

 static bool
 panfrost_blend_constant(float *out, float *in, unsigned mask)
 {
         /* If there is no components used, it automatically works */

         if (!mask)
                 return true;

         /* Find some starter mask */
         unsigned first = ffs(mask) - 1;
         float cons = in[first];
         mask ^= (1 << first);

         /* Ensure the rest are equal */
         while (mask) {
                 unsigned i = u_bit_scan(&mask);

                 if (in[i] != cons)
                         return false;
         }

         /* Otherwise, we're good to go */
         *out = cons;
         return true;
 }

 /* Create a final blend given the context */

 struct panfrost_blend_final
 panfrost_get_blend_for_context(struct panfrost_context *ctx, unsigned rti)
 {
         struct panfrost_batch *batch = panfrost_get_batch_for_fbo(ctx);
         struct pipe_framebuffer_state *fb = &ctx->pipe_framebuffer;
         enum pipe_format fmt = fb->cbufs[rti]->format;

         /* Grab the blend state */
         struct panfrost_blend_state *blend = ctx->blend;
         struct panfrost_blend_rt *rt = &blend->rt[rti];

         /* First, we'll try fixed function, matching equationn and constant */
         if (rt->has_fixed_function && panfrost_can_fixed_blend(fmt)) {
                 float constant = 0.0;

                 if (panfrost_blend_constant(
                             &constant,
                             ctx->blend_color.color,
                             rt->constant_mask)) {
                         bool no_blending =
                                 (rt->equation.rgb_mode == 0x122) &&
                                 (rt->equation.alpha_mode == 0x122) &&
                                 (rt->equation.color_mask == 0xf);

                         struct panfrost_blend_final final = {
                                 .equation = {
                                         .equation = &rt->equation,
                                         .constant = constant
                                 },
                                 .no_blending = no_blending,
                                 .no_colour = (rt->equation.color_mask == 0x0)
                         };

                         return final;
                 }
         }

         /* Otherwise, we need to grab a shader */
         struct panfrost_blend_shader *shader = panfrost_get_blend_shader(ctx, blend, fmt, rti);

         struct panfrost_bo *bo = panfrost_batch_create_bo(batch, shader->size,
                    PAN_BO_EXECUTE,
                    PAN_BO_ACCESS_PRIVATE |
                    PAN_BO_ACCESS_READ |
                    PAN_BO_ACCESS_FRAGMENT);

         memcpy(bo->cpu, shader->buffer, shader->size);

         if (shader->patch_index) {
                 /* We have to specialize the blend shader to use constants, so
                  * patch in the current constants */

                 float *patch = (float *) (bo->cpu + shader->patch_index);
                 memcpy(patch, ctx->blend_color.color, sizeof(float) * 4);
         }

         struct panfrost_blend_final final = {
                 .is_shader = true,
                 .shader = {
                         .work_count = shader->work_count,
                         .first_tag = shader->first_tag,
                         .gpu = bo->gpu,
                 }
         };

         return final;
 }

 void
 panfrost_blend_context_init(struct pipe_context *pipe)
 {
         pipe->create_blend_state = panfrost_create_blend_state;
         pipe->bind_blend_state   = panfrost_bind_blend_state;
         pipe->delete_blend_state = panfrost_delete_blend_state;

         pipe->set_blend_color = panfrost_set_blend_color;
 }
	/*
	* 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 <alyssa.rosenzweig@collabora.com>
	*
	*/

	#include <stdio.h>
	#include "util/u_memory.h"
	#include "pan_blend_shaders.h"
	#include "pan_blending.h"
	#include "pan_bo.h"
	#include "panfrost-quirks.h"

	/* A given Gallium blend state can be encoded to the hardware in numerous,
	* dramatically divergent ways due to the interactions of blending with
	* framebuffer formats. Conceptually, there are two modes:
	*
	* - Fixed-function blending (for suitable framebuffer formats, suitable blend
	* state, and suitable blend constant)
	*
	* - Blend shaders (for everything else)
	*
	* A given Gallium blend configuration will compile to exactly one
	* fixed-function blend state, if it compiles to any, although the constant
	* will vary across runs as that is tracked outside of the Gallium CSO.
	*
	* However, that same blend configuration will compile to many different blend
	* shaders, depending on the framebuffer formats active. The rationale is that
	* blend shaders override not just fixed-function blending but also
	* fixed-function format conversion. As such, each blend shader must be
	* hardcoded to a particular framebuffer format to correctly pack/unpack it. As
	* a concrete example, to the hardware there is no difference (!) between RG16F
	* and RG16UI -- both are simply 4-byte-per-pixel chunks. Thus both formats
	* require a blend shader (even with blending is totally disabled!), required
	* to do conversion as necessary (if necessary).
	*
	* All of this state is encapsulated in the panfrost_blend_state struct
	* (our subclass of pipe_blend_state).
	*/

	/* Given an initialized CSO and a particular framebuffer format, grab a
	* blend shader, generating and compiling it if it doesn't exist
	* (lazy-loading in a way). This routine, when the cache hits, should
	* befast, suitable for calling every draw to avoid wacky dirty
	* tracking paths. If the cache hits, boom, done. */

	struct panfrost_blend_shader *
	panfrost_get_blend_shader(
	struct panfrost_context *ctx,
	struct panfrost_blend_state *blend,
	enum pipe_format fmt,
	unsigned rt)
	{
	/* Prevent NULL collision issues.. */
	assert(fmt != 0);

	/* Check the cache. Key by the RT and format */
	struct hash_table_u64 *shaders = blend->rt[rt].shaders;
	unsigned key = (fmt << 3) \| rt;

	struct panfrost_blend_shader *shader =
	_mesa_hash_table_u64_search(shaders, key);

	if (shader)
	return shader;

	/* Cache miss. Build one instead, cache it, and go */

	struct panfrost_blend_shader generated =
	panfrost_compile_blend_shader(ctx, &blend->base, fmt, rt);

	shader = mem_dup(&generated, sizeof(generated));
	_mesa_hash_table_u64_insert(shaders, key, shader);
	return shader;
	}

	/* Create a blend CSO. Essentially, try to compile a fixed-function
	* expression and initialize blend shaders */

	static void *
	panfrost_create_blend_state(struct pipe_context *pipe,
	const struct pipe_blend_state *blend)
	{
	struct panfrost_context *ctx = pan_context(pipe);
	struct panfrost_blend_state *so = rzalloc(ctx, struct panfrost_blend_state);
	so->base = *blend;

	/* TODO: The following features are not yet implemented */
	assert(!blend->alpha_to_one);

	for (unsigned c = 0; c < PIPE_MAX_COLOR_BUFS; ++c) {
	struct panfrost_blend_rt *rt = &so->rt[c];

	/* There are two paths. First, we would like to try a
	* fixed-function if we can */

	/* Without indep blending, the first RT settings replicate */

	if (!blend->logicop_enable) {
	unsigned g =
	blend->independent_blend_enable ? c : 0;

	rt->has_fixed_function =
	panfrost_make_fixed_blend_mode(
	&blend->rt[g],
	&rt->equation,
	&rt->constant_mask,
	blend->rt[g].colormask);
	}

	/* Regardless if that works, we also need to initialize
	* the blend shaders */

	rt->shaders = _mesa_hash_table_u64_create(so);
	}

	return so;
	}

	static void
	panfrost_bind_blend_state(struct pipe_context *pipe,
	void *cso)
	{
	struct panfrost_context *ctx = pan_context(pipe);
	struct pipe_blend_state blend = (struct pipe_blend_state ) cso;
	struct panfrost_blend_state pblend = (struct panfrost_blend_state ) cso;
	ctx->blend = pblend;

	if (!blend)
	return;
	}

	static void
	panfrost_delete_blend_shader(struct hash_entry *entry)
	{
	struct panfrost_blend_shader shader = (struct panfrost_blend_shader )entry->data;
	free(shader->buffer);
	free(shader);
	}

	static void
	panfrost_delete_blend_state(struct pipe_context *pipe,
	void *cso)
	{
	struct panfrost_blend_state blend = (struct panfrost_blend_state ) cso;

	for (unsigned c = 0; c < PIPE_MAX_COLOR_BUFS; ++c) {
	struct panfrost_blend_rt *rt = &blend->rt[c];
	_mesa_hash_table_u64_clear(rt->shaders, panfrost_delete_blend_shader);
	}
	ralloc_free(blend);
	}

	static void
	panfrost_set_blend_color(struct pipe_context *pipe,
	const struct pipe_blend_color *blend_color)
	{
	struct panfrost_context *ctx = pan_context(pipe);

	if (blend_color)
	ctx->blend_color = *blend_color;
	}

	/* Given a vec4 of constants, reduce it to just a single constant according to
	* the mask (if we can) */

	static bool
	panfrost_blend_constant(float out, float in, unsigned mask)
	{
	/* If there is no components used, it automatically works */

	if (!mask)
	return true;

	/* Find some starter mask */
	unsigned first = ffs(mask) - 1;
	float cons = in[first];
	mask ^= (1 << first);

	/* Ensure the rest are equal */
	while (mask) {
	unsigned i = u_bit_scan(&mask);

	if (in[i] != cons)
	return false;
	}

	/* Otherwise, we're good to go */
	*out = cons;
	return true;
	}

	/* Create a final blend given the context */

	struct panfrost_blend_final
	panfrost_get_blend_for_context(struct panfrost_context *ctx, unsigned rti)
	{
	struct panfrost_batch *batch = panfrost_get_batch_for_fbo(ctx);
	struct pipe_framebuffer_state *fb = &ctx->pipe_framebuffer;
	enum pipe_format fmt = fb->cbufs[rti]->format;

	/* Grab the blend state */
	struct panfrost_blend_state *blend = ctx->blend;
	struct panfrost_blend_rt *rt = &blend->rt[rti];

	/* First, we'll try fixed function, matching equationn and constant */
	if (rt->has_fixed_function && panfrost_can_fixed_blend(fmt)) {
	float constant = 0.0;

	if (panfrost_blend_constant(
	&constant,
	ctx->blend_color.color,
	rt->constant_mask)) {
	bool no_blending =
	(rt->equation.rgb_mode == 0x122) &&
	(rt->equation.alpha_mode == 0x122) &&
	(rt->equation.color_mask == 0xf);

	struct panfrost_blend_final final = {
	.equation = {
	.equation = &rt->equation,
	.constant = constant
	},
	.no_blending = no_blending,
	.no_colour = (rt->equation.color_mask == 0x0)
	};

	return final;
	}
	}

	/* Otherwise, we need to grab a shader */
	struct panfrost_blend_shader *shader = panfrost_get_blend_shader(ctx, blend, fmt, rti);

	struct panfrost_bo *bo = panfrost_batch_create_bo(batch, shader->size,
	PAN_BO_EXECUTE,
	PAN_BO_ACCESS_PRIVATE \|
	PAN_BO_ACCESS_READ \|
	PAN_BO_ACCESS_FRAGMENT);

	memcpy(bo->cpu, shader->buffer, shader->size);

	if (shader->patch_index) {
	/* We have to specialize the blend shader to use constants, so
	* patch in the current constants */

	float patch = (float ) (bo->cpu + shader->patch_index);
	memcpy(patch, ctx->blend_color.color, sizeof(float) * 4);
	}

	struct panfrost_blend_final final = {
	.is_shader = true,
	.shader = {
	.work_count = shader->work_count,
	.first_tag = shader->first_tag,
	.gpu = bo->gpu,
	}
	};

	return final;
	}

	void
	panfrost_blend_context_init(struct pipe_context *pipe)
	{
	pipe->create_blend_state = panfrost_create_blend_state;
	pipe->bind_blend_state = panfrost_bind_blend_state;
	pipe->delete_blend_state = panfrost_delete_blend_state;

	pipe->set_blend_color = panfrost_set_blend_color;
	}