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Merge tag 'drm-misc-fixes-2022-04-22' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

Two fixes for the raspberrypi panel initialisation, one fix for a logic inversion in radeon, a build and pm refcounting fix for vc4, two reverts for drm_of_get_bridge that caused a number of regression and a locking regression for amdgpu. Signed-off-by: Dave Airlie <airlied@redhat.com>

Dave Airlie committed 4 years ago

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include/linux/dma-buf-map.h+0−266
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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Pointer to dma-buf-mapped memory, plus helpers.
4 */
5
6#ifndef __DMA_BUF_MAP_H__
7#define __DMA_BUF_MAP_H__
8
9#include <linux/io.h>
10#include <linux/string.h>
11
12/**
13 * DOC: overview
14 *
15 * Calling dma-buf's vmap operation returns a pointer to the buffer's memory.
16 * Depending on the location of the buffer, users may have to access it with
17 * I/O operations or memory load/store operations. For example, copying to
18 * system memory could be done with memcpy(), copying to I/O memory would be
19 * done with memcpy_toio().
20 *
21 * .. code-block:: c
22 *
23 * void *vaddr = ...; // pointer to system memory
24 * memcpy(vaddr, src, len);
25 *
26 * void *vaddr_iomem = ...; // pointer to I/O memory
27 * memcpy_toio(vaddr, _iomem, src, len);
28 *
29 * When using dma-buf's vmap operation, the returned pointer is encoded as
30 * :c:type:`struct dma_buf_map <dma_buf_map>`.
31 * :c:type:`struct dma_buf_map <dma_buf_map>` stores the buffer's address in
32 * system or I/O memory and a flag that signals the required method of
33 * accessing the buffer. Use the returned instance and the helper functions
34 * to access the buffer's memory in the correct way.
35 *
36 * The type :c:type:`struct dma_buf_map <dma_buf_map>` and its helpers are
37 * actually independent from the dma-buf infrastructure. When sharing buffers
38 * among devices, drivers have to know the location of the memory to access
39 * the buffers in a safe way. :c:type:`struct dma_buf_map <dma_buf_map>`
40 * solves this problem for dma-buf and its users. If other drivers or
41 * sub-systems require similar functionality, the type could be generalized
42 * and moved to a more prominent header file.
43 *
44 * Open-coding access to :c:type:`struct dma_buf_map <dma_buf_map>` is
45 * considered bad style. Rather then accessing its fields directly, use one
46 * of the provided helper functions, or implement your own. For example,
47 * instances of :c:type:`struct dma_buf_map <dma_buf_map>` can be initialized
48 * statically with DMA_BUF_MAP_INIT_VADDR(), or at runtime with
49 * dma_buf_map_set_vaddr(). These helpers will set an address in system memory.
50 *
51 * .. code-block:: c
52 *
53 * struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(0xdeadbeaf);
54 *
55 * dma_buf_map_set_vaddr(&map, 0xdeadbeaf);
56 *
57 * To set an address in I/O memory, use dma_buf_map_set_vaddr_iomem().
58 *
59 * .. code-block:: c
60 *
61 * dma_buf_map_set_vaddr_iomem(&map, 0xdeadbeaf);
62 *
63 * Instances of struct dma_buf_map do not have to be cleaned up, but
64 * can be cleared to NULL with dma_buf_map_clear(). Cleared mappings
65 * always refer to system memory.
66 *
67 * .. code-block:: c
68 *
69 * dma_buf_map_clear(&map);
70 *
71 * Test if a mapping is valid with either dma_buf_map_is_set() or
72 * dma_buf_map_is_null().
73 *
74 * .. code-block:: c
75 *
76 * if (dma_buf_map_is_set(&map) != dma_buf_map_is_null(&map))
77 * // always true
78 *
79 * Instances of :c:type:`struct dma_buf_map <dma_buf_map>` can be compared
80 * for equality with dma_buf_map_is_equal(). Mappings the point to different
81 * memory spaces, system or I/O, are never equal. That's even true if both
82 * spaces are located in the same address space, both mappings contain the
83 * same address value, or both mappings refer to NULL.
84 *
85 * .. code-block:: c
86 *
87 * struct dma_buf_map sys_map; // refers to system memory
88 * struct dma_buf_map io_map; // refers to I/O memory
89 *
90 * if (dma_buf_map_is_equal(&sys_map, &io_map))
91 * // always false
92 *
93 * A set up instance of struct dma_buf_map can be used to access or manipulate
94 * the buffer memory. Depending on the location of the memory, the provided
95 * helpers will pick the correct operations. Data can be copied into the memory
96 * with dma_buf_map_memcpy_to(). The address can be manipulated with
97 * dma_buf_map_incr().
98 *
99 * .. code-block:: c
100 *
101 * const void *src = ...; // source buffer
102 * size_t len = ...; // length of src
103 *
104 * dma_buf_map_memcpy_to(&map, src, len);
105 * dma_buf_map_incr(&map, len); // go to first byte after the memcpy
106 */
107
108/**
109 * struct dma_buf_map - Pointer to vmap'ed dma-buf memory.
110 * @vaddr_iomem: The buffer's address if in I/O memory
111 * @vaddr: The buffer's address if in system memory
112 * @is_iomem: True if the dma-buf memory is located in I/O
113 * memory, or false otherwise.
114 */
115struct dma_buf_map {
116 union {
117 void __iomem *vaddr_iomem;
118 void *vaddr;
119 };
120 bool is_iomem;
121};
122
123/**
124 * DMA_BUF_MAP_INIT_VADDR - Initializes struct dma_buf_map to an address in system memory
125 * @vaddr_: A system-memory address
126 */
127#define DMA_BUF_MAP_INIT_VADDR(vaddr_) \
128 { \
129 .vaddr = (vaddr_), \
130 .is_iomem = false, \
131 }
132
133/**
134 * dma_buf_map_set_vaddr - Sets a dma-buf mapping structure to an address in system memory
135 * @map: The dma-buf mapping structure
136 * @vaddr: A system-memory address
137 *
138 * Sets the address and clears the I/O-memory flag.
139 */
140static inline void dma_buf_map_set_vaddr(struct dma_buf_map *map, void *vaddr)
141{
142 map->vaddr = vaddr;
143 map->is_iomem = false;
144}
145
146/**
147 * dma_buf_map_set_vaddr_iomem - Sets a dma-buf mapping structure to an address in I/O memory
148 * @map: The dma-buf mapping structure
149 * @vaddr_iomem: An I/O-memory address
150 *
151 * Sets the address and the I/O-memory flag.
152 */
153static inline void dma_buf_map_set_vaddr_iomem(struct dma_buf_map *map,
154 void __iomem *vaddr_iomem)
155{
156 map->vaddr_iomem = vaddr_iomem;
157 map->is_iomem = true;
158}
159
160/**
161 * dma_buf_map_is_equal - Compares two dma-buf mapping structures for equality
162 * @lhs: The dma-buf mapping structure
163 * @rhs: A dma-buf mapping structure to compare with
164 *
165 * Two dma-buf mapping structures are equal if they both refer to the same type of memory
166 * and to the same address within that memory.
167 *
168 * Returns:
169 * True is both structures are equal, or false otherwise.
170 */
171static inline bool dma_buf_map_is_equal(const struct dma_buf_map *lhs,
172 const struct dma_buf_map *rhs)
173{
174 if (lhs->is_iomem != rhs->is_iomem)
175 return false;
176 else if (lhs->is_iomem)
177 return lhs->vaddr_iomem == rhs->vaddr_iomem;
178 else
179 return lhs->vaddr == rhs->vaddr;
180}
181
182/**
183 * dma_buf_map_is_null - Tests for a dma-buf mapping to be NULL
184 * @map: The dma-buf mapping structure
185 *
186 * Depending on the state of struct dma_buf_map.is_iomem, tests if the
187 * mapping is NULL.
188 *
189 * Returns:
190 * True if the mapping is NULL, or false otherwise.
191 */
192static inline bool dma_buf_map_is_null(const struct dma_buf_map *map)
193{
194 if (map->is_iomem)
195 return !map->vaddr_iomem;
196 return !map->vaddr;
197}
198
199/**
200 * dma_buf_map_is_set - Tests is the dma-buf mapping has been set
201 * @map: The dma-buf mapping structure
202 *
203 * Depending on the state of struct dma_buf_map.is_iomem, tests if the
204 * mapping has been set.
205 *
206 * Returns:
207 * True if the mapping is been set, or false otherwise.
208 */
209static inline bool dma_buf_map_is_set(const struct dma_buf_map *map)
210{
211 return !dma_buf_map_is_null(map);
212}
213
214/**
215 * dma_buf_map_clear - Clears a dma-buf mapping structure
216 * @map: The dma-buf mapping structure
217 *
218 * Clears all fields to zero; including struct dma_buf_map.is_iomem. So
219 * mapping structures that were set to point to I/O memory are reset for
220 * system memory. Pointers are cleared to NULL. This is the default.
221 */
222static inline void dma_buf_map_clear(struct dma_buf_map *map)
223{
224 if (map->is_iomem) {
225 map->vaddr_iomem = NULL;
226 map->is_iomem = false;
227 } else {
228 map->vaddr = NULL;
229 }
230}
231
232/**
233 * dma_buf_map_memcpy_to - Memcpy into dma-buf mapping
234 * @dst: The dma-buf mapping structure
235 * @src: The source buffer
236 * @len: The number of byte in src
237 *
238 * Copies data into a dma-buf mapping. The source buffer is in system
239 * memory. Depending on the buffer's location, the helper picks the correct
240 * method of accessing the memory.
241 */
242static inline void dma_buf_map_memcpy_to(struct dma_buf_map *dst, const void *src, size_t len)
243{
244 if (dst->is_iomem)
245 memcpy_toio(dst->vaddr_iomem, src, len);
246 else
247 memcpy(dst->vaddr, src, len);
248}
249
250/**
251 * dma_buf_map_incr - Increments the address stored in a dma-buf mapping
252 * @map: The dma-buf mapping structure
253 * @incr: The number of bytes to increment
254 *
255 * Increments the address stored in a dma-buf mapping. Depending on the
256 * buffer's location, the correct value will be updated.
257 */
258static inline void dma_buf_map_incr(struct dma_buf_map *map, size_t incr)
259{
260 if (map->is_iomem)
261 map->vaddr_iomem += incr;
262 else
263 map->vaddr += incr;
264}
265
266#endif /* __DMA_BUF_MAP_H__ */