1 /*
2 * Copyright © 2017 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included
12 * in all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
20 * DEALINGS IN THE SOFTWARE.
21 */
22
23 /**
24 * @file iris_formats.c
25 *
26 * Converts Gallium formats (PIPE_FORMAT_*) to hardware ones (ISL_FORMAT_*).
27 * Provides information about which formats support what features.
28 */
29
30 #include "util/bitscan.h"
31 #include "util/macros.h"
32 #include "util/format/u_format.h"
33
34 #include "iris_resource.h"
35 #include "iris_screen.h"
36
37 struct iris_format_info
iris_format_for_usage(const struct gen_device_info * devinfo,enum pipe_format pformat,isl_surf_usage_flags_t usage)38 iris_format_for_usage(const struct gen_device_info *devinfo,
39 enum pipe_format pformat,
40 isl_surf_usage_flags_t usage)
41 {
42 enum isl_format format = isl_format_for_pipe_format(pformat);
43 struct isl_swizzle swizzle = ISL_SWIZZLE_IDENTITY;
44
45 if (format == ISL_FORMAT_UNSUPPORTED)
46 return (struct iris_format_info) { .fmt = format, .swizzle = swizzle };
47
48 const struct isl_format_layout *fmtl = isl_format_get_layout(format);
49
50 if (!util_format_is_srgb(pformat)) {
51 if (util_format_is_intensity(pformat)) {
52 swizzle = ISL_SWIZZLE(RED, RED, RED, RED);
53 } else if (util_format_is_luminance(pformat)) {
54 swizzle = ISL_SWIZZLE(RED, RED, RED, ONE);
55 } else if (util_format_is_luminance_alpha(pformat)) {
56 swizzle = ISL_SWIZZLE(RED, RED, RED, GREEN);
57 } else if (util_format_is_alpha(pformat)) {
58 swizzle = ISL_SWIZZLE(ZERO, ZERO, ZERO, RED);
59 }
60 }
61
62 /* When faking RGBX pipe formats with RGBA ISL formats, override alpha. */
63 if (!util_format_has_alpha(pformat) && fmtl->channels.a.type != ISL_VOID) {
64 swizzle = ISL_SWIZZLE(RED, GREEN, BLUE, ONE);
65 }
66
67 if ((usage & ISL_SURF_USAGE_RENDER_TARGET_BIT) &&
68 pformat == PIPE_FORMAT_A8_UNORM) {
69 /* Most of the hardware A/LA formats are not renderable, except
70 * for A8_UNORM. SURFACE_STATE's shader channel select fields
71 * cannot be used to swap RGB and A channels when rendering (as
72 * it could impact alpha blending), so we have to use the actual
73 * A8_UNORM format when rendering.
74 */
75 format = ISL_FORMAT_A8_UNORM;
76 swizzle = ISL_SWIZZLE_IDENTITY;
77 }
78
79 /* We choose RGBA over RGBX for rendering the hardware doesn't support
80 * rendering to RGBX. However, when this internal override is used on Gen9+,
81 * fast clears don't work correctly.
82 *
83 * i965 fixes this by pretending to not support RGBX formats, and the higher
84 * layers of Mesa pick the RGBA format instead. Gallium doesn't work that
85 * way, and might choose a different format, like BGRX instead of RGBX,
86 * which will also cause problems when sampling from a surface fast cleared
87 * as RGBX. So we always choose RGBA instead of RGBX explicitly
88 * here.
89 */
90 if (isl_format_is_rgbx(format) &&
91 !isl_format_supports_rendering(devinfo, format)) {
92 format = isl_format_rgbx_to_rgba(format);
93 swizzle = ISL_SWIZZLE(RED, GREEN, BLUE, ONE);
94 }
95
96 return (struct iris_format_info) { .fmt = format, .swizzle = swizzle };
97 }
98
99 /**
100 * The pscreen->is_format_supported() driver hook.
101 *
102 * Returns true if the given format is supported for the given usage
103 * (PIPE_BIND_*) and sample count.
104 */
105 bool
iris_is_format_supported(struct pipe_screen * pscreen,enum pipe_format pformat,enum pipe_texture_target target,unsigned sample_count,unsigned storage_sample_count,unsigned usage)106 iris_is_format_supported(struct pipe_screen *pscreen,
107 enum pipe_format pformat,
108 enum pipe_texture_target target,
109 unsigned sample_count,
110 unsigned storage_sample_count,
111 unsigned usage)
112 {
113 struct iris_screen *screen = (struct iris_screen *) pscreen;
114 const struct gen_device_info *devinfo = &screen->devinfo;
115 uint32_t max_samples = devinfo->gen == 8 ? 8 : 16;
116
117 if (sample_count > max_samples ||
118 !util_is_power_of_two_or_zero(sample_count))
119 return false;
120
121 if (pformat == PIPE_FORMAT_NONE)
122 return true;
123
124 enum isl_format format = isl_format_for_pipe_format(pformat);
125
126 if (format == ISL_FORMAT_UNSUPPORTED)
127 return false;
128
129 const struct isl_format_layout *fmtl = isl_format_get_layout(format);
130 const bool is_integer = isl_format_has_int_channel(format);
131 bool supported = true;
132
133 if (sample_count > 1)
134 supported &= isl_format_supports_multisampling(devinfo, format);
135
136 if (usage & PIPE_BIND_DEPTH_STENCIL) {
137 supported &= format == ISL_FORMAT_R32_FLOAT_X8X24_TYPELESS ||
138 format == ISL_FORMAT_R32_FLOAT ||
139 format == ISL_FORMAT_R24_UNORM_X8_TYPELESS ||
140 format == ISL_FORMAT_R16_UNORM ||
141 format == ISL_FORMAT_R8_UINT;
142 }
143
144 if (usage & PIPE_BIND_RENDER_TARGET) {
145 /* Alpha and luminance-alpha formats other than A8_UNORM are not
146 * renderable. For texturing, we can use R or RG formats with
147 * shader channel selects (SCS) to swizzle the data into the correct
148 * channels. But for render targets, the hardware prohibits using
149 * SCS to move shader outputs between the RGB and A channels, as it
150 * would alter what data is used for alpha blending.
151 *
152 * For BLORP, we can apply the swizzle in the shader. But for
153 * general rendering, this would mean recompiling the shader, which
154 * we'd like to avoid doing. So we mark these formats non-renderable.
155 *
156 * We do support A8_UNORM as it's required and is renderable.
157 */
158 if (pformat != PIPE_FORMAT_A8_UNORM &&
159 (util_format_is_alpha(pformat) ||
160 util_format_is_luminance_alpha(pformat)))
161 supported = false;
162
163 enum isl_format rt_format = format;
164
165 if (isl_format_is_rgbx(format) &&
166 !isl_format_supports_rendering(devinfo, format))
167 rt_format = isl_format_rgbx_to_rgba(format);
168
169 supported &= isl_format_supports_rendering(devinfo, rt_format);
170
171 if (!is_integer)
172 supported &= isl_format_supports_alpha_blending(devinfo, rt_format);
173 }
174
175 if (usage & PIPE_BIND_SHADER_IMAGE) {
176 /* Dataport doesn't support compression, and we can't resolve an MCS
177 * compressed surface. (Buffer images may have sample count of 0.)
178 */
179 supported &= sample_count == 0;
180
181 supported &= isl_format_supports_typed_writes(devinfo, format);
182 supported &= isl_has_matching_typed_storage_image_format(devinfo, format);
183 }
184
185 if (usage & PIPE_BIND_SAMPLER_VIEW) {
186 supported &= isl_format_supports_sampling(devinfo, format);
187 if (!is_integer)
188 supported &= isl_format_supports_filtering(devinfo, format);
189
190 /* Don't advertise 3-component RGB formats for non-buffer textures.
191 * This ensures that they are renderable from an API perspective since
192 * gallium frontends will fall back to RGBA or RGBX, which are
193 * renderable. We want to render internally for copies and blits,
194 * even if the application doesn't.
195 *
196 * Buffer textures don't need to be renderable, so we support real RGB.
197 * This is useful for PBO upload, and 32-bit RGB support is mandatory.
198 */
199 if (target != PIPE_BUFFER)
200 supported &= fmtl->bpb != 24 && fmtl->bpb != 48 && fmtl->bpb != 96;
201 }
202
203 if (usage & PIPE_BIND_VERTEX_BUFFER)
204 supported &= isl_format_supports_vertex_fetch(devinfo, format);
205
206 if (usage & PIPE_BIND_INDEX_BUFFER) {
207 supported &= format == ISL_FORMAT_R8_UINT ||
208 format == ISL_FORMAT_R16_UINT ||
209 format == ISL_FORMAT_R32_UINT;
210 }
211
212 /* TODO: Support ASTC 5x5 on Gen9 properly. This means implementing
213 * a complex sampler workaround (see i965's gen9_apply_astc5x5_wa_flush).
214 * Without it, st/mesa will emulate ASTC 5x5 via uncompressed textures.
215 */
216 if (devinfo->gen == 9 && (format == ISL_FORMAT_ASTC_LDR_2D_5X5_FLT16 ||
217 format == ISL_FORMAT_ASTC_LDR_2D_5X5_U8SRGB))
218 return false;
219
220 return supported;
221 }
222
223