1 /*
2 * Copyright © 2018 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 (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 */
23
24 #ifndef INTEL_GEM_H
25 #define INTEL_GEM_H
26
27 #include "drm-uapi/i915_drm.h"
28
29 #include <assert.h>
30 #include <errno.h>
31 #include <stdbool.h>
32 #include <stdint.h>
33 #include <stdlib.h>
34 #include <unistd.h>
35 #include <sys/ioctl.h>
36
37 static inline uint64_t
intel_canonical_address(uint64_t v)38 intel_canonical_address(uint64_t v)
39 {
40 /* From the Broadwell PRM Vol. 2a, MI_LOAD_REGISTER_MEM::MemoryAddress:
41 *
42 * "This field specifies the address of the memory location where the
43 * register value specified in the DWord above will read from. The
44 * address specifies the DWord location of the data. Range =
45 * GraphicsVirtualAddress[63:2] for a DWord register GraphicsAddress
46 * [63:48] are ignored by the HW and assumed to be in correct
47 * canonical form [63:48] == [47]."
48 */
49 const int shift = 63 - 47;
50 return (int64_t)(v << shift) >> shift;
51 }
52
53 /**
54 * This returns a 48-bit address with the high 16 bits zeroed.
55 *
56 * It's the opposite of intel_canonicalize_address.
57 */
58 static inline uint64_t
intel_48b_address(uint64_t v)59 intel_48b_address(uint64_t v)
60 {
61 const int shift = 63 - 47;
62 return (uint64_t)(v << shift) >> shift;
63 }
64
65 /**
66 * Call ioctl, restarting if it is interupted
67 */
68 static inline int
intel_ioctl(int fd,unsigned long request,void * arg)69 intel_ioctl(int fd, unsigned long request, void *arg)
70 {
71 int ret;
72
73 do {
74 ret = ioctl(fd, request, arg);
75 } while (ret == -1 && (errno == EINTR || errno == EAGAIN));
76 return ret;
77 }
78
79 /**
80 * A wrapper around DRM_IOCTL_I915_QUERY
81 *
82 * Unfortunately, the error semantics of this ioctl are rather annoying so
83 * it's better to have a common helper.
84 */
85 static inline int
intel_i915_query_flags(int fd,uint64_t query_id,uint32_t flags,void * buffer,int32_t * buffer_len)86 intel_i915_query_flags(int fd, uint64_t query_id, uint32_t flags,
87 void *buffer, int32_t *buffer_len)
88 {
89 struct drm_i915_query_item item = {
90 .query_id = query_id,
91 .length = *buffer_len,
92 .flags = flags,
93 .data_ptr = (uintptr_t)buffer,
94 };
95
96 struct drm_i915_query args = {
97 .num_items = 1,
98 .flags = 0,
99 .items_ptr = (uintptr_t)&item,
100 };
101
102 int ret = intel_ioctl(fd, DRM_IOCTL_I915_QUERY, &args);
103 if (ret != 0)
104 return -errno;
105 else if (item.length < 0)
106 return item.length;
107
108 *buffer_len = item.length;
109 return 0;
110 }
111
112 static inline int
intel_i915_query(int fd,uint64_t query_id,void * buffer,int32_t * buffer_len)113 intel_i915_query(int fd, uint64_t query_id, void *buffer,
114 int32_t *buffer_len)
115 {
116 return intel_i915_query_flags(fd, query_id, 0, buffer, buffer_len);
117 }
118
119 /**
120 * Query for the given data, allocating as needed
121 *
122 * The caller is responsible for freeing the returned pointer.
123 */
124 static inline void *
intel_i915_query_alloc(int fd,uint64_t query_id)125 intel_i915_query_alloc(int fd, uint64_t query_id)
126 {
127 int32_t length = 0;
128 int ret = intel_i915_query(fd, query_id, NULL, &length);
129 if (ret < 0)
130 return NULL;
131
132 void *data = calloc(1, length);
133 assert(data != NULL); /* This shouldn't happen in practice */
134 if (data == NULL)
135 return NULL;
136
137 ret = intel_i915_query(fd, query_id, data, &length);
138 assert(ret == 0); /* We should have caught the error above */
139 if (ret < 0) {
140 free(data);
141 return NULL;
142 }
143
144 return data;
145 }
146
147 bool intel_gem_supports_syncobj_wait(int fd);
148
149 #endif /* INTEL_GEM_H */
150