xref: /linux/drivers/gpu/drm/vkms/vkms_drv.h (revision 3f1c07fc21c68bd3bd2df9d2c9441f6485e934d9)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 
3 #ifndef _VKMS_DRV_H_
4 #define _VKMS_DRV_H_
5 
6 #include <linux/hrtimer.h>
7 
8 #include <drm/drm.h>
9 #include <drm/drm_framebuffer.h>
10 #include <drm/drm_gem.h>
11 #include <drm/drm_gem_atomic_helper.h>
12 #include <drm/drm_encoder.h>
13 #include <drm/drm_writeback.h>
14 
15 #define DEFAULT_DEVICE_NAME "vkms"
16 
17 #define XRES_MIN    10
18 #define YRES_MIN    10
19 
20 #define XRES_DEF  1024
21 #define YRES_DEF   768
22 
23 #define XRES_MAX  8192
24 #define YRES_MAX  8192
25 
26 #define NUM_OVERLAY_PLANES 8
27 
28 #define VKMS_LUT_SIZE 256
29 
30 /**
31  * struct vkms_frame_info - Structure to store the state of a frame
32  *
33  * @fb: backing drm framebuffer
34  * @src: source rectangle of this frame in the source framebuffer, stored in 16.16 fixed-point form
35  * @dst: destination rectangle in the crtc buffer, stored in whole pixel units
36  * @map: see @drm_shadow_plane_state.data
37  * @rotation: rotation applied to the source.
38  *
39  * @src and @dst should have the same size modulo the rotation.
40  */
41 struct vkms_frame_info {
42 	struct drm_framebuffer *fb;
43 	struct drm_rect src, dst;
44 	struct iosys_map map[DRM_FORMAT_MAX_PLANES];
45 	unsigned int rotation;
46 };
47 
48 struct pixel_argb_s32 {
49 	s32 a, r, g, b;
50 };
51 
52 /**
53  * struct pixel_argb_u16 - Internal representation of a pixel color.
54  * @a: Alpha component value, stored in 16 bits, without padding, using
55  *     machine endianness
56  * @r: Red component value, stored in 16 bits, without padding, using
57  *     machine endianness
58  * @g: Green component value, stored in 16 bits, without padding, using
59  *     machine endianness
60  * @b: Blue component value, stored in 16 bits, without padding, using
61  *     machine endianness
62  *
63  * The goal of this structure is to keep enough precision to ensure
64  * correct composition results in VKMS and simplifying color
65  * manipulation by splitting each component into its own field.
66  * Caution: the byte ordering of this structure is machine-dependent,
67  * you can't cast it directly to AR48 or xR48.
68  */
69 struct pixel_argb_u16 {
70 	u16 a, r, g, b;
71 };
72 
73 struct line_buffer {
74 	size_t n_pixels;
75 	struct pixel_argb_u16 *pixels;
76 };
77 
78 /**
79  * typedef pixel_write_t - These functions are used to read a pixel from a
80  * &struct pixel_argb_u16, convert it in a specific format and write it in the @out_pixel
81  * buffer.
82  *
83  * @out_pixel: destination address to write the pixel
84  * @in_pixel: pixel to write
85  */
86 typedef void (*pixel_write_t)(u8 *out_pixel, const struct pixel_argb_u16 *in_pixel);
87 
88 struct vkms_writeback_job {
89 	struct iosys_map data[DRM_FORMAT_MAX_PLANES];
90 	struct vkms_frame_info wb_frame_info;
91 	pixel_write_t pixel_write;
92 };
93 
94 /**
95  * enum pixel_read_direction - Enum used internally by VKMS to represent a reading direction in a
96  * plane.
97  */
98 enum pixel_read_direction {
99 	READ_BOTTOM_TO_TOP,
100 	READ_TOP_TO_BOTTOM,
101 	READ_RIGHT_TO_LEFT,
102 	READ_LEFT_TO_RIGHT
103 };
104 
105 struct vkms_plane_state;
106 
107 /**
108  * typedef pixel_read_line_t - These functions are used to read a pixel line in the source frame,
109  * convert it to `struct pixel_argb_u16` and write it to @out_pixel.
110  *
111  * @plane: plane used as source for the pixel value
112  * @x_start: X (width) coordinate of the first pixel to copy. The caller must ensure that x_start
113  * is non-negative and smaller than @plane->frame_info->fb->width.
114  * @y_start: Y (height) coordinate of the first pixel to copy. The caller must ensure that y_start
115  * is non-negative and smaller than @plane->frame_info->fb->height.
116  * @direction: direction to use for the copy, starting at @x_start/@y_start
117  * @count: number of pixels to copy
118  * @out_pixel: pointer where to write the pixel values. They will be written from @out_pixel[0]
119  * (included) to @out_pixel[@count] (excluded). The caller must ensure that out_pixel have a
120  * length of at least @count.
121  */
122 typedef void (*pixel_read_line_t)(const struct vkms_plane_state *plane, int x_start,
123 				  int y_start, enum pixel_read_direction direction, int count,
124 				  struct pixel_argb_u16 out_pixel[]);
125 
126 /**
127  * struct conversion_matrix - Matrix to use for a specific encoding and range
128  *
129  * @matrix: Conversion matrix from yuv to rgb. The matrix is stored in a row-major manner and is
130  * used to compute rgb values from yuv values:
131  *     [[r],[g],[b]] = @matrix * [[y],[u],[v]]
132  *   OR for yvu formats:
133  *     [[r],[g],[b]] = @matrix * [[y],[v],[u]]
134  *  The values of the matrix are signed fixed-point values with 32 bits fractional part.
135  * @y_offset: Offset to apply on the y value.
136  */
137 struct conversion_matrix {
138 	s64 matrix[3][3];
139 	int y_offset;
140 };
141 
142 /**
143  * struct vkms_plane_state - Driver specific plane state
144  * @base: base plane state
145  * @frame_info: data required for composing computation
146  * @pixel_read_line: function to read a pixel line in this plane. The creator of a
147  *		     struct vkms_plane_state must ensure that this pointer is valid
148  * @conversion_matrix: matrix used for yuv formats to convert to rgb
149  */
150 struct vkms_plane_state {
151 	struct drm_shadow_plane_state base;
152 	struct vkms_frame_info *frame_info;
153 	pixel_read_line_t pixel_read_line;
154 	struct conversion_matrix conversion_matrix;
155 };
156 
157 struct vkms_plane {
158 	struct drm_plane base;
159 };
160 
161 struct vkms_color_lut {
162 	struct drm_color_lut *base;
163 	size_t lut_length;
164 	s64 channel_value2index_ratio;
165 };
166 
167 /**
168  * struct vkms_crtc_state - Driver specific CRTC state
169  *
170  * @base: base CRTC state
171  * @composer_work: work struct to compose and add CRC entries
172  *
173  * @num_active_planes: Number of active planes
174  * @active_planes: List containing all the active planes (counted by
175  *		   @num_active_planes). They should be stored in z-order.
176  * @active_writeback: Current active writeback job
177  * @gamma_lut: Look up table for gamma used in this CRTC
178  * @crc_pending: Protected by @vkms_output.composer_lock, true when the frame CRC is not computed
179  *		 yet. Used by vblank to detect if the composer is too slow.
180  * @wb_pending: Protected by @vkms_output.composer_lock, true when a writeback frame is requested.
181  * @frame_start: Protected by @vkms_output.composer_lock, saves the frame number before the start
182  *		 of the composition process.
183  * @frame_end: Protected by @vkms_output.composer_lock, saves the last requested frame number.
184  *	       This is used to generate enough CRC entries when the composition worker is too slow.
185  */
186 struct vkms_crtc_state {
187 	struct drm_crtc_state base;
188 	struct work_struct composer_work;
189 
190 	int num_active_planes;
191 	struct vkms_plane_state **active_planes;
192 	struct vkms_writeback_job *active_writeback;
193 	struct vkms_color_lut gamma_lut;
194 
195 	bool crc_pending;
196 	bool wb_pending;
197 	u64 frame_start;
198 	u64 frame_end;
199 };
200 
201 /**
202  * struct vkms_output - Internal representation of all output components in VKMS
203  *
204  * @crtc: Base CRTC in DRM
205  * @encoder: DRM encoder used for this output
206  * @connector: DRM connector used for this output
207  * @wb_connecter: DRM writeback connector used for this output
208  * @vblank_hrtimer: Timer used to trigger the vblank
209  * @period_ns: vblank period, in nanoseconds, used to configure @vblank_hrtimer and to compute
210  *	       vblank timestamps
211  * @composer_workq: Ordered workqueue for @composer_state.composer_work.
212  * @lock: Lock used to protect concurrent access to the composer
213  * @composer_enabled: Protected by @lock, true when the VKMS composer is active (crc needed or
214  *		      writeback)
215  * @composer_state: Protected by @lock, current state of this VKMS output
216  * @composer_lock: Lock used internally to protect @composer_state members
217  */
218 struct vkms_output {
219 	struct drm_crtc crtc;
220 	struct drm_writeback_connector wb_connector;
221 	struct drm_encoder wb_encoder;
222 	struct workqueue_struct *composer_workq;
223 	spinlock_t lock;
224 
225 	bool composer_enabled;
226 	struct vkms_crtc_state *composer_state;
227 
228 	spinlock_t composer_lock;
229 };
230 
231 struct vkms_config;
232 struct vkms_config_plane;
233 
234 /**
235  * struct vkms_device - Description of a VKMS device
236  *
237  * @drm - Base device in DRM
238  * @faux_dev - Associated faux device
239  * @output - Configuration and sub-components of the VKMS device
240  * @config: Configuration used in this VKMS device
241  */
242 struct vkms_device {
243 	struct drm_device drm;
244 	struct faux_device *faux_dev;
245 	const struct vkms_config *config;
246 };
247 
248 /*
249  * The following helpers are used to convert a member of a struct into its parent.
250  */
251 
252 #define drm_crtc_to_vkms_output(target) \
253 	container_of(target, struct vkms_output, crtc)
254 
255 #define drm_device_to_vkms_device(target) \
256 	container_of(target, struct vkms_device, drm)
257 
258 #define to_vkms_crtc_state(target)\
259 	container_of(target, struct vkms_crtc_state, base)
260 
261 #define to_vkms_plane_state(target)\
262 	container_of(target, struct vkms_plane_state, base.base)
263 
264 /**
265  * vkms_create() - Create a device from a configuration
266  * @config: Config used to configure the new device
267  *
268  * A pointer to the created vkms_device is stored in @config
269  *
270  * Returns:
271  * 0 on success or an error.
272  */
273 int vkms_create(struct vkms_config *config);
274 
275 /**
276  * vkms_destroy() - Destroy a device
277  * @config: Config from which the device was created
278  *
279  * The device is completely removed, but the @config is not freed. It can be
280  * reused or destroyed with vkms_config_destroy().
281  */
282 void vkms_destroy(struct vkms_config *config);
283 
284 /**
285  * vkms_crtc_init() - Initialize a CRTC for VKMS
286  * @dev: DRM device associated with the VKMS buffer
287  * @crtc: uninitialized CRTC device
288  * @primary: primary plane to attach to the CRTC
289  * @cursor: plane to attach to the CRTC
290  */
291 struct vkms_output *vkms_crtc_init(struct drm_device *dev,
292 				   struct drm_plane *primary,
293 				   struct drm_plane *cursor);
294 
295 /**
296  * vkms_output_init() - Initialize all sub-components needed for a VKMS device.
297  *
298  * @vkmsdev: VKMS device to initialize
299  */
300 int vkms_output_init(struct vkms_device *vkmsdev);
301 
302 /**
303  * vkms_plane_init() - Initialize a plane
304  *
305  * @vkmsdev: VKMS device containing the plane
306  * @plane_cfg: plane configuration
307  */
308 struct vkms_plane *vkms_plane_init(struct vkms_device *vkmsdev,
309 				   struct vkms_config_plane *plane_cfg);
310 
311 /* CRC Support */
312 const char *const *vkms_get_crc_sources(struct drm_crtc *crtc,
313 					size_t *count);
314 int vkms_set_crc_source(struct drm_crtc *crtc, const char *src_name);
315 int vkms_verify_crc_source(struct drm_crtc *crtc, const char *source_name,
316 			   size_t *values_cnt);
317 
318 /* Composer Support */
319 void vkms_composer_worker(struct work_struct *work);
320 void vkms_set_composer(struct vkms_output *out, bool enabled);
321 void vkms_writeback_row(struct vkms_writeback_job *wb, const struct line_buffer *src_buffer, int y);
322 
323 /* Writeback */
324 int vkms_enable_writeback_connector(struct vkms_device *vkmsdev, struct vkms_output *vkms_out);
325 
326 /* Colorops */
327 int vkms_initialize_colorops(struct drm_plane *plane);
328 
329 #endif /* _VKMS_DRV_H_ */
330