xref: /linux/drivers/gpu/drm/imagination/pvr_gem.h (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
1 /* SPDX-License-Identifier: GPL-2.0-only OR MIT */
2 /* Copyright (c) 2023 Imagination Technologies Ltd. */
3 
4 #ifndef PVR_GEM_H
5 #define PVR_GEM_H
6 
7 #include "pvr_rogue_heap_config.h"
8 #include "pvr_rogue_meta.h"
9 
10 #include <uapi/drm/pvr_drm.h>
11 
12 #include <drm/drm_gem.h>
13 #include <drm/drm_gem_shmem_helper.h>
14 #include <drm/drm_mm.h>
15 
16 #include <linux/bitfield.h>
17 #include <linux/bits.h>
18 #include <linux/const.h>
19 #include <linux/compiler_attributes.h>
20 #include <linux/kernel.h>
21 #include <linux/mutex.h>
22 #include <linux/refcount.h>
23 #include <linux/scatterlist.h>
24 #include <linux/sizes.h>
25 #include <linux/types.h>
26 
27 /* Forward declaration from "pvr_device.h". */
28 struct pvr_device;
29 struct pvr_file;
30 
31 /**
32  * DOC: Flags for DRM_IOCTL_PVR_CREATE_BO (kernel-only)
33  *
34  * Kernel-only values allowed in &pvr_gem_object->flags. The majority of options
35  * for this field are specified in the UAPI header "pvr_drm.h" with a
36  * DRM_PVR_BO_ prefix. To distinguish these internal options (which must exist
37  * in ranges marked as "reserved" in the UAPI header), we drop the DRM prefix.
38  * The public options should be used directly, DRM prefix and all.
39  *
40  * To avoid potentially confusing gaps in the UAPI options, these kernel-only
41  * options are specified "in reverse", starting at bit 63.
42  *
43  * We use "reserved" to refer to bits defined here and not exposed in the UAPI.
44  * Bits not defined anywhere are "undefined".
45  *
46  * CPU mapping options
47  *    :PVR_BO_CPU_CACHED: By default, all GEM objects are mapped write-combined on the CPU. Set
48  *       this flag to override this behaviour and map the object cached. If the dma_coherent
49  *       property is present in devicetree, all allocations will be mapped as if this flag was set.
50  *       This does not require any additional consideration at allocation time.
51  *
52  * Firmware options
53  *    :PVR_BO_FW_NO_CLEAR_ON_RESET: By default, all FW objects are cleared and reinitialised on hard
54  *       reset. Set this flag to override this behaviour and preserve buffer contents on reset.
55  */
56 #define PVR_BO_CPU_CACHED BIT_ULL(63)
57 
58 #define PVR_BO_FW_NO_CLEAR_ON_RESET BIT_ULL(62)
59 
60 #define PVR_BO_KERNEL_FLAGS_MASK (PVR_BO_CPU_CACHED | PVR_BO_FW_NO_CLEAR_ON_RESET)
61 
62 /* Bits 61..3 are undefined. */
63 /* Bits 2..0 are defined in the UAPI. */
64 
65 /* Other utilities. */
66 #define PVR_BO_UNDEFINED_MASK ~(PVR_BO_KERNEL_FLAGS_MASK | DRM_PVR_BO_FLAGS_MASK)
67 
68 /*
69  * All firmware-mapped memory uses (mostly) the same flags. Specifically,
70  * firmware-mapped memory should be:
71  *  * Read/write on the device,
72  *  * Read/write on the CPU, and
73  *  * Write-combined on the CPU.
74  *
75  * The only variation is in caching on the device.
76  */
77 #define PVR_BO_FW_FLAGS_DEVICE_CACHED (ULL(0))
78 #define PVR_BO_FW_FLAGS_DEVICE_UNCACHED DRM_PVR_BO_BYPASS_DEVICE_CACHE
79 
80 /**
81  * struct pvr_gem_object - powervr-specific wrapper for &struct drm_gem_object
82  */
83 struct pvr_gem_object {
84 	/**
85 	 * @base: The underlying &struct drm_gem_shmem_object.
86 	 *
87 	 * Do not access this member directly, instead call
88 	 * shem_gem_from_pvr_gem().
89 	 */
90 	struct drm_gem_shmem_object base;
91 
92 	/**
93 	 * @flags: Options set at creation-time. Some of these options apply to
94 	 * the creation operation itself (which are stored here for reference)
95 	 * with the remainder used for mapping options to both the device and
96 	 * CPU. These are used every time this object is mapped, but may be
97 	 * changed after creation.
98 	 *
99 	 * Must be a combination of DRM_PVR_BO_* and/or PVR_BO_* flags.
100 	 *
101 	 * .. note::
102 	 *
103 	 *    This member is declared const to indicate that none of these
104 	 *    options may change or be changed throughout the object's
105 	 *    lifetime.
106 	 */
107 	u64 flags;
108 
109 };
110 
111 static_assert(offsetof(struct pvr_gem_object, base) == 0,
112 	      "offsetof(struct pvr_gem_object, base) not zero");
113 
114 #define shmem_gem_from_pvr_gem(pvr_obj) (&(pvr_obj)->base)
115 
116 #define shmem_gem_to_pvr_gem(shmem_obj) container_of_const(shmem_obj, struct pvr_gem_object, base)
117 
118 #define gem_from_pvr_gem(pvr_obj) (&(pvr_obj)->base.base)
119 
120 #define gem_to_pvr_gem(gem_obj) container_of_const(gem_obj, struct pvr_gem_object, base.base)
121 
122 /* Functions defined in pvr_gem.c */
123 
124 struct drm_gem_object *pvr_gem_create_object(struct drm_device *drm_dev, size_t size);
125 
126 struct pvr_gem_object *pvr_gem_object_create(struct pvr_device *pvr_dev,
127 					     size_t size, u64 flags);
128 
129 int pvr_gem_object_into_handle(struct pvr_gem_object *pvr_obj,
130 			       struct pvr_file *pvr_file, u32 *handle);
131 struct pvr_gem_object *pvr_gem_object_from_handle(struct pvr_file *pvr_file,
132 						  u32 handle);
133 
134 static __always_inline struct sg_table *
pvr_gem_object_get_pages_sgt(struct pvr_gem_object * pvr_obj)135 pvr_gem_object_get_pages_sgt(struct pvr_gem_object *pvr_obj)
136 {
137 	return drm_gem_shmem_get_pages_sgt(shmem_gem_from_pvr_gem(pvr_obj));
138 }
139 
140 void *pvr_gem_object_vmap(struct pvr_gem_object *pvr_obj);
141 void pvr_gem_object_vunmap(struct pvr_gem_object *pvr_obj);
142 
143 int pvr_gem_get_dma_addr(struct pvr_gem_object *pvr_obj, u32 offset,
144 			 dma_addr_t *dma_addr_out);
145 
146 /**
147  * pvr_gem_object_get() - Acquire reference on pvr_gem_object
148  * @pvr_obj: Pointer to object to acquire reference on.
149  */
150 static __always_inline void
pvr_gem_object_get(struct pvr_gem_object * pvr_obj)151 pvr_gem_object_get(struct pvr_gem_object *pvr_obj)
152 {
153 	drm_gem_object_get(gem_from_pvr_gem(pvr_obj));
154 }
155 
156 /**
157  * pvr_gem_object_put() - Release reference on pvr_gem_object
158  * @pvr_obj: Pointer to object to release reference on.
159  */
160 static __always_inline void
pvr_gem_object_put(struct pvr_gem_object * pvr_obj)161 pvr_gem_object_put(struct pvr_gem_object *pvr_obj)
162 {
163 	drm_gem_object_put(gem_from_pvr_gem(pvr_obj));
164 }
165 
166 static __always_inline size_t
pvr_gem_object_size(struct pvr_gem_object * pvr_obj)167 pvr_gem_object_size(struct pvr_gem_object *pvr_obj)
168 {
169 	return gem_from_pvr_gem(pvr_obj)->size;
170 }
171 
172 #endif /* PVR_GEM_H */
173