1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/*
* SPDX-License-Identifier: MIT
*
* Copyright © 2019 Intel Corporation
*/
#include "i915_drv.h"
#include "intel_lrc_reg.h"
#include "intel_sseu.h"
void intel_sseu_set_info(struct sseu_dev_info *sseu, u8 max_slices,
u8 max_subslices, u8 max_eus_per_subslice)
{
sseu->max_slices = max_slices;
sseu->max_subslices = max_subslices;
sseu->max_eus_per_subslice = max_eus_per_subslice;
sseu->ss_stride = GEN_SSEU_STRIDE(sseu->max_subslices);
GEM_BUG_ON(sseu->ss_stride > GEN_MAX_SUBSLICE_STRIDE);
sseu->eu_stride = GEN_SSEU_STRIDE(sseu->max_eus_per_subslice);
GEM_BUG_ON(sseu->eu_stride > GEN_MAX_EU_STRIDE);
}
unsigned int
intel_sseu_subslice_total(const struct sseu_dev_info *sseu)
{
unsigned int i, total = 0;
for (i = 0; i < ARRAY_SIZE(sseu->subslice_mask); i++)
total += hweight8(sseu->subslice_mask[i]);
return total;
}
u32 intel_sseu_get_subslices(const struct sseu_dev_info *sseu, u8 slice)
{
int i, offset = slice * sseu->ss_stride;
u32 mask = 0;
GEM_BUG_ON(slice >= sseu->max_slices);
for (i = 0; i < sseu->ss_stride; i++)
mask |= (u32)sseu->subslice_mask[offset + i] <<
i * BITS_PER_BYTE;
return mask;
}
void intel_sseu_set_subslices(struct sseu_dev_info *sseu, int slice,
u32 ss_mask)
{
int offset = slice * sseu->ss_stride;
memcpy(&sseu->subslice_mask[offset], &ss_mask, sseu->ss_stride);
}
unsigned int
intel_sseu_subslices_per_slice(const struct sseu_dev_info *sseu, u8 slice)
{
return hweight32(intel_sseu_get_subslices(sseu, slice));
}
u32 intel_sseu_make_rpcs(struct drm_i915_private *i915,
const struct intel_sseu *req_sseu)
{
const struct sseu_dev_info *sseu = &RUNTIME_INFO(i915)->sseu;
bool subslice_pg = sseu->has_subslice_pg;
struct intel_sseu ctx_sseu;
u8 slices, subslices;
u32 rpcs = 0;
/*
* No explicit RPCS request is needed to ensure full
* slice/subslice/EU enablement prior to Gen9.
*/
if (INTEL_GEN(i915) < 9)
return 0;
/*
* If i915/perf is active, we want a stable powergating configuration
* on the system.
*
* We could choose full enablement, but on ICL we know there are use
* cases which disable slices for functional, apart for performance
* reasons. So in this case we select a known stable subset.
*/
if (!i915->perf.exclusive_stream) {
ctx_sseu = *req_sseu;
} else {
ctx_sseu = intel_sseu_from_device_info(sseu);
if (IS_GEN(i915, 11)) {
/*
* We only need subslice count so it doesn't matter
* which ones we select - just turn off low bits in the
* amount of half of all available subslices per slice.
*/
ctx_sseu.subslice_mask =
~(~0 << (hweight8(ctx_sseu.subslice_mask) / 2));
ctx_sseu.slice_mask = 0x1;
}
}
slices = hweight8(ctx_sseu.slice_mask);
subslices = hweight8(ctx_sseu.subslice_mask);
/*
* Since the SScount bitfield in GEN8_R_PWR_CLK_STATE is only three bits
* wide and Icelake has up to eight subslices, specfial programming is
* needed in order to correctly enable all subslices.
*
* According to documentation software must consider the configuration
* as 2x4x8 and hardware will translate this to 1x8x8.
*
* Furthemore, even though SScount is three bits, maximum documented
* value for it is four. From this some rules/restrictions follow:
*
* 1.
* If enabled subslice count is greater than four, two whole slices must
* be enabled instead.
*
* 2.
* When more than one slice is enabled, hardware ignores the subslice
* count altogether.
*
* From these restrictions it follows that it is not possible to enable
* a count of subslices between the SScount maximum of four restriction,
* and the maximum available number on a particular SKU. Either all
* subslices are enabled, or a count between one and four on the first
* slice.
*/
if (IS_GEN(i915, 11) &&
slices == 1 &&
subslices > min_t(u8, 4, hweight8(sseu->subslice_mask[0]) / 2)) {
GEM_BUG_ON(subslices & 1);
subslice_pg = false;
slices *= 2;
}
/*
* Starting in Gen9, render power gating can leave
* slice/subslice/EU in a partially enabled state. We
* must make an explicit request through RPCS for full
* enablement.
*/
if (sseu->has_slice_pg) {
u32 mask, val = slices;
if (INTEL_GEN(i915) >= 11) {
mask = GEN11_RPCS_S_CNT_MASK;
val <<= GEN11_RPCS_S_CNT_SHIFT;
} else {
mask = GEN8_RPCS_S_CNT_MASK;
val <<= GEN8_RPCS_S_CNT_SHIFT;
}
GEM_BUG_ON(val & ~mask);
val &= mask;
rpcs |= GEN8_RPCS_ENABLE | GEN8_RPCS_S_CNT_ENABLE | val;
}
if (subslice_pg) {
u32 val = subslices;
val <<= GEN8_RPCS_SS_CNT_SHIFT;
GEM_BUG_ON(val & ~GEN8_RPCS_SS_CNT_MASK);
val &= GEN8_RPCS_SS_CNT_MASK;
rpcs |= GEN8_RPCS_ENABLE | GEN8_RPCS_SS_CNT_ENABLE | val;
}
if (sseu->has_eu_pg) {
u32 val;
val = ctx_sseu.min_eus_per_subslice << GEN8_RPCS_EU_MIN_SHIFT;
GEM_BUG_ON(val & ~GEN8_RPCS_EU_MIN_MASK);
val &= GEN8_RPCS_EU_MIN_MASK;
rpcs |= val;
val = ctx_sseu.max_eus_per_subslice << GEN8_RPCS_EU_MAX_SHIFT;
GEM_BUG_ON(val & ~GEN8_RPCS_EU_MAX_MASK);
val &= GEN8_RPCS_EU_MAX_MASK;
rpcs |= val;
rpcs |= GEN8_RPCS_ENABLE;
}
return rpcs;
}
|