1/*
2 * Copyright 2014 Advanced Micro Devices, Inc.
3 * All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the next
13 * paragraph) shall be included in all copies or substantial portions of the
14 * Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
23 */
24
25#include "si_build_pm4.h"
26
27/* For MSAA sample positions. */
28#define FILL_SREG(s0x, s0y, s1x, s1y, s2x, s2y, s3x, s3y)  \
29	((((unsigned)(s0x) & 0xf) << 0)  | (((unsigned)(s0y) & 0xf) << 4)  | \
30	 (((unsigned)(s1x) & 0xf) << 8)  | (((unsigned)(s1y) & 0xf) << 12) | \
31	 (((unsigned)(s2x) & 0xf) << 16) | (((unsigned)(s2y) & 0xf) << 20) | \
32	 (((unsigned)(s3x) & 0xf) << 24) | (((unsigned)(s3y) & 0xf) << 28))
33
34/* For obtaining location coordinates from registers */
35#define SEXT4(x)		((int)((x) | ((x) & 0x8 ? 0xfffffff0 : 0)))
36#define GET_SFIELD(reg, index)	SEXT4(((reg) >> ((index) * 4)) & 0xf)
37#define GET_SX(reg, index)	GET_SFIELD((reg)[(index) / 4], ((index) % 4) * 2)
38#define GET_SY(reg, index)	GET_SFIELD((reg)[(index) / 4], ((index) % 4) * 2 + 1)
39
40/* The following sample ordering is required by EQAA.
41 *
42 * Sample 0 is approx. in the top-left quadrant.
43 * Sample 1 is approx. in the bottom-right quadrant.
44 *
45 * Sample 2 is approx. in the bottom-left quadrant.
46 * Sample 3 is approx. in the top-right quadrant.
47 * (sample I={2,3} adds more detail to the vicinity of sample I-2)
48 *
49 * Sample 4 is approx. in the same quadrant as sample 0. (top-left)
50 * Sample 5 is approx. in the same quadrant as sample 1. (bottom-right)
51 * Sample 6 is approx. in the same quadrant as sample 2. (bottom-left)
52 * Sample 7 is approx. in the same quadrant as sample 3. (top-right)
53 * (sample I={4,5,6,7} adds more detail to the vicinity of sample I-4)
54 *
55 * The next 8 samples add more detail to the vicinity of the previous samples.
56 * (sample I (I >= 8) adds more detail to the vicinity of sample I-8)
57 *
58 * The ordering is specified such that:
59 *   If we take the first 2 samples, we should get good 2x MSAA.
60 *   If we add 2 more samples, we should get good 4x MSAA with the same sample locations.
61 *   If we add 4 more samples, we should get good 8x MSAA with the same sample locations.
62 *   If we add 8 more samples, we should get perfect 16x MSAA with the same sample locations.
63 *
64 * The ordering also allows finding samples in the same vicinity.
65 *
66 * Group N of 2 samples in the same vicinity in 16x MSAA: {N,N+8}
67 * Group N of 2 samples in the same vicinity in 8x MSAA: {N,N+4}
68 * Group N of 2 samples in the same vicinity in 4x MSAA: {N,N+2}
69 *
70 * Groups of 4 samples in the same vicinity in 16x MSAA:
71 *   Top left:     {0,4,8,12}
72 *   Bottom right: {1,5,9,13}
73 *   Bottom left:  {2,6,10,14}
74 *   Top right:    {3,7,11,15}
75 *
76 * Groups of 4 samples in the same vicinity in 8x MSAA:
77 *   Left half:  {0,2,4,6}
78 *   Right half: {1,3,5,7}
79 *
80 * Groups of 8 samples in the same vicinity in 16x MSAA:
81 *   Left half:  {0,2,4,6,8,10,12,14}
82 *   Right half: {1,3,5,7,9,11,13,15}
83 */
84
85/* 1x MSAA */
86static const uint32_t sample_locs_1x =
87	FILL_SREG( 0, 0,   0, 0,   0, 0,   0, 0); /* S1, S2, S3 fields are not used by 1x */
88static const uint64_t centroid_priority_1x = 0x0000000000000000ull;
89
90/* 2x MSAA (the positions are sorted for EQAA) */
91static const uint32_t sample_locs_2x =
92	FILL_SREG(-4,-4,   4, 4,   0, 0,   0, 0); /* S2 & S3 fields are not used by 2x MSAA */
93static const uint64_t centroid_priority_2x = 0x1010101010101010ull;
94
95/* 4x MSAA (the positions are sorted for EQAA) */
96static const uint32_t sample_locs_4x =
97	FILL_SREG(-2,-6,   2, 6,   -6, 2,  6,-2);
98static const uint64_t centroid_priority_4x = 0x3210321032103210ull;
99
100/* 8x MSAA (the positions are sorted for EQAA) */
101static const uint32_t sample_locs_8x[] = {
102	FILL_SREG(-3,-5,   5, 1,  -1, 3,   7,-7),
103	FILL_SREG(-7,-1,   3, 7,  -5, 5,   1,-3),
104	/* The following are unused by hardware, but we emit them to IBs
105	 * instead of multiple SET_CONTEXT_REG packets. */
106	0,
107	0,
108};
109static const uint64_t centroid_priority_8x = 0x3546012735460127ull;
110
111/* 16x MSAA (the positions are sorted for EQAA) */
112static const uint32_t sample_locs_16x[] = {
113	FILL_SREG(-5,-2,   5, 3,  -2, 6,   3,-5),
114	FILL_SREG(-4,-6,   1, 1,  -6, 4,   7,-4),
115	FILL_SREG(-1,-3,   6, 7,  -3, 2,   0,-7),
116	FILL_SREG(-7,-8,   2, 5,  -8, 0,   4,-1),
117};
118static const uint64_t centroid_priority_16x = 0xc97e64b231d0fa85ull;
119
120static void si_get_sample_position(struct pipe_context *ctx, unsigned sample_count,
121				   unsigned sample_index, float *out_value)
122{
123	const uint32_t *sample_locs;
124
125	switch (sample_count) {
126	case 1:
127	default:
128		sample_locs = &sample_locs_1x;
129		break;
130	case 2:
131		sample_locs = &sample_locs_2x;
132		break;
133	case 4:
134		sample_locs = &sample_locs_4x;
135		break;
136	case 8:
137		sample_locs = sample_locs_8x;
138		break;
139	case 16:
140		sample_locs = sample_locs_16x;
141		break;
142	}
143
144	out_value[0] = (GET_SX(sample_locs, sample_index) + 8) / 16.0f;
145	out_value[1] = (GET_SY(sample_locs, sample_index) + 8) / 16.0f;
146}
147
148static void si_emit_max_4_sample_locs(struct radeon_cmdbuf *cs,
149				      uint64_t centroid_priority,
150				      uint32_t sample_locs)
151{
152	radeon_set_context_reg_seq(cs, R_028BD4_PA_SC_CENTROID_PRIORITY_0, 2);
153	radeon_emit(cs, centroid_priority);
154	radeon_emit(cs, centroid_priority >> 32);
155	radeon_set_context_reg(cs, R_028BF8_PA_SC_AA_SAMPLE_LOCS_PIXEL_X0Y0_0, sample_locs);
156	radeon_set_context_reg(cs, R_028C08_PA_SC_AA_SAMPLE_LOCS_PIXEL_X1Y0_0, sample_locs);
157	radeon_set_context_reg(cs, R_028C18_PA_SC_AA_SAMPLE_LOCS_PIXEL_X0Y1_0, sample_locs);
158	radeon_set_context_reg(cs, R_028C28_PA_SC_AA_SAMPLE_LOCS_PIXEL_X1Y1_0, sample_locs);
159}
160
161static void si_emit_max_16_sample_locs(struct radeon_cmdbuf *cs,
162				       uint64_t centroid_priority,
163				       const uint32_t *sample_locs,
164				       unsigned num_samples)
165{
166	radeon_set_context_reg_seq(cs, R_028BD4_PA_SC_CENTROID_PRIORITY_0, 2);
167	radeon_emit(cs, centroid_priority);
168	radeon_emit(cs, centroid_priority >> 32);
169	radeon_set_context_reg_seq(cs, R_028BF8_PA_SC_AA_SAMPLE_LOCS_PIXEL_X0Y0_0,
170				   num_samples == 8 ? 14 : 16);
171	radeon_emit_array(cs, sample_locs, 4);
172	radeon_emit_array(cs, sample_locs, 4);
173	radeon_emit_array(cs, sample_locs, 4);
174	radeon_emit_array(cs, sample_locs, num_samples == 8 ? 2 : 4);
175}
176
177void si_emit_sample_locations(struct radeon_cmdbuf *cs, int nr_samples)
178{
179	switch (nr_samples) {
180	default:
181	case 1:
182		si_emit_max_4_sample_locs(cs, centroid_priority_1x, sample_locs_1x);
183		break;
184	case 2:
185		si_emit_max_4_sample_locs(cs, centroid_priority_2x, sample_locs_2x);
186		break;
187	case 4:
188		si_emit_max_4_sample_locs(cs, centroid_priority_4x, sample_locs_4x);
189		break;
190	case 8:
191		si_emit_max_16_sample_locs(cs, centroid_priority_8x, sample_locs_8x, 8);
192		break;
193	case 16:
194		si_emit_max_16_sample_locs(cs, centroid_priority_16x, sample_locs_16x, 16);
195		break;
196	}
197}
198
199void si_init_msaa_functions(struct si_context *sctx)
200{
201	int i;
202
203	sctx->b.get_sample_position = si_get_sample_position;
204
205	si_get_sample_position(&sctx->b, 1, 0, sctx->sample_positions.x1[0]);
206
207	for (i = 0; i < 2; i++)
208		si_get_sample_position(&sctx->b, 2, i, sctx->sample_positions.x2[i]);
209	for (i = 0; i < 4; i++)
210		si_get_sample_position(&sctx->b, 4, i, sctx->sample_positions.x4[i]);
211	for (i = 0; i < 8; i++)
212		si_get_sample_position(&sctx->b, 8, i, sctx->sample_positions.x8[i]);
213	for (i = 0; i < 16; i++)
214		si_get_sample_position(&sctx->b, 16, i, sctx->sample_positions.x16[i]);
215}
216