xref: /openbmc/linux/drivers/gpu/drm/vc4/vc4_plane.c (revision 029f7f3b8701cc7aca8bdb31f0c7edd6a479e357)
1 /*
2  * Copyright (C) 2015 Broadcom
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 /**
10  * DOC: VC4 plane module
11  *
12  * Each DRM plane is a layer of pixels being scanned out by the HVS.
13  *
14  * At atomic modeset check time, we compute the HVS display element
15  * state that would be necessary for displaying the plane (giving us a
16  * chance to figure out if a plane configuration is invalid), then at
17  * atomic flush time the CRTC will ask us to write our element state
18  * into the region of the HVS that it has allocated for us.
19  */
20 
21 #include "vc4_drv.h"
22 #include "vc4_regs.h"
23 #include "drm_atomic_helper.h"
24 #include "drm_fb_cma_helper.h"
25 #include "drm_plane_helper.h"
26 
27 struct vc4_plane_state {
28 	struct drm_plane_state base;
29 	u32 *dlist;
30 	u32 dlist_size; /* Number of dwords in allocated for the display list */
31 	u32 dlist_count; /* Number of used dwords in the display list. */
32 };
33 
34 static inline struct vc4_plane_state *
35 to_vc4_plane_state(struct drm_plane_state *state)
36 {
37 	return (struct vc4_plane_state *)state;
38 }
39 
40 static const struct hvs_format {
41 	u32 drm; /* DRM_FORMAT_* */
42 	u32 hvs; /* HVS_FORMAT_* */
43 	u32 pixel_order;
44 	bool has_alpha;
45 } hvs_formats[] = {
46 	{
47 		.drm = DRM_FORMAT_XRGB8888, .hvs = HVS_PIXEL_FORMAT_RGBA8888,
48 		.pixel_order = HVS_PIXEL_ORDER_ABGR, .has_alpha = false,
49 	},
50 	{
51 		.drm = DRM_FORMAT_ARGB8888, .hvs = HVS_PIXEL_FORMAT_RGBA8888,
52 		.pixel_order = HVS_PIXEL_ORDER_ABGR, .has_alpha = true,
53 	},
54 };
55 
56 static const struct hvs_format *vc4_get_hvs_format(u32 drm_format)
57 {
58 	unsigned i;
59 
60 	for (i = 0; i < ARRAY_SIZE(hvs_formats); i++) {
61 		if (hvs_formats[i].drm == drm_format)
62 			return &hvs_formats[i];
63 	}
64 
65 	return NULL;
66 }
67 
68 static bool plane_enabled(struct drm_plane_state *state)
69 {
70 	return state->fb && state->crtc;
71 }
72 
73 struct drm_plane_state *vc4_plane_duplicate_state(struct drm_plane *plane)
74 {
75 	struct vc4_plane_state *vc4_state;
76 
77 	if (WARN_ON(!plane->state))
78 		return NULL;
79 
80 	vc4_state = kmemdup(plane->state, sizeof(*vc4_state), GFP_KERNEL);
81 	if (!vc4_state)
82 		return NULL;
83 
84 	__drm_atomic_helper_plane_duplicate_state(plane, &vc4_state->base);
85 
86 	if (vc4_state->dlist) {
87 		vc4_state->dlist = kmemdup(vc4_state->dlist,
88 					   vc4_state->dlist_count * 4,
89 					   GFP_KERNEL);
90 		if (!vc4_state->dlist) {
91 			kfree(vc4_state);
92 			return NULL;
93 		}
94 		vc4_state->dlist_size = vc4_state->dlist_count;
95 	}
96 
97 	return &vc4_state->base;
98 }
99 
100 void vc4_plane_destroy_state(struct drm_plane *plane,
101 			     struct drm_plane_state *state)
102 {
103 	struct vc4_plane_state *vc4_state = to_vc4_plane_state(state);
104 
105 	kfree(vc4_state->dlist);
106 	__drm_atomic_helper_plane_destroy_state(plane, &vc4_state->base);
107 	kfree(state);
108 }
109 
110 /* Called during init to allocate the plane's atomic state. */
111 void vc4_plane_reset(struct drm_plane *plane)
112 {
113 	struct vc4_plane_state *vc4_state;
114 
115 	WARN_ON(plane->state);
116 
117 	vc4_state = kzalloc(sizeof(*vc4_state), GFP_KERNEL);
118 	if (!vc4_state)
119 		return;
120 
121 	plane->state = &vc4_state->base;
122 	vc4_state->base.plane = plane;
123 }
124 
125 static void vc4_dlist_write(struct vc4_plane_state *vc4_state, u32 val)
126 {
127 	if (vc4_state->dlist_count == vc4_state->dlist_size) {
128 		u32 new_size = max(4u, vc4_state->dlist_count * 2);
129 		u32 *new_dlist = kmalloc(new_size * 4, GFP_KERNEL);
130 
131 		if (!new_dlist)
132 			return;
133 		memcpy(new_dlist, vc4_state->dlist, vc4_state->dlist_count * 4);
134 
135 		kfree(vc4_state->dlist);
136 		vc4_state->dlist = new_dlist;
137 		vc4_state->dlist_size = new_size;
138 	}
139 
140 	vc4_state->dlist[vc4_state->dlist_count++] = val;
141 }
142 
143 /* Writes out a full display list for an active plane to the plane's
144  * private dlist state.
145  */
146 static int vc4_plane_mode_set(struct drm_plane *plane,
147 			      struct drm_plane_state *state)
148 {
149 	struct vc4_plane_state *vc4_state = to_vc4_plane_state(state);
150 	struct drm_framebuffer *fb = state->fb;
151 	struct drm_gem_cma_object *bo = drm_fb_cma_get_gem_obj(fb, 0);
152 	u32 ctl0_offset = vc4_state->dlist_count;
153 	const struct hvs_format *format = vc4_get_hvs_format(fb->pixel_format);
154 	uint32_t offset = fb->offsets[0];
155 	int crtc_x = state->crtc_x;
156 	int crtc_y = state->crtc_y;
157 	int crtc_w = state->crtc_w;
158 	int crtc_h = state->crtc_h;
159 
160 	if (crtc_x < 0) {
161 		offset += drm_format_plane_cpp(fb->pixel_format, 0) * -crtc_x;
162 		crtc_w += crtc_x;
163 		crtc_x = 0;
164 	}
165 
166 	if (crtc_y < 0) {
167 		offset += fb->pitches[0] * -crtc_y;
168 		crtc_h += crtc_y;
169 		crtc_y = 0;
170 	}
171 
172 	vc4_dlist_write(vc4_state,
173 			SCALER_CTL0_VALID |
174 			(format->pixel_order << SCALER_CTL0_ORDER_SHIFT) |
175 			(format->hvs << SCALER_CTL0_PIXEL_FORMAT_SHIFT) |
176 			SCALER_CTL0_UNITY);
177 
178 	/* Position Word 0: Image Positions and Alpha Value */
179 	vc4_dlist_write(vc4_state,
180 			VC4_SET_FIELD(0xff, SCALER_POS0_FIXED_ALPHA) |
181 			VC4_SET_FIELD(crtc_x, SCALER_POS0_START_X) |
182 			VC4_SET_FIELD(crtc_y, SCALER_POS0_START_Y));
183 
184 	/* Position Word 1: Scaled Image Dimensions.
185 	 * Skipped due to SCALER_CTL0_UNITY scaling.
186 	 */
187 
188 	/* Position Word 2: Source Image Size, Alpha Mode */
189 	vc4_dlist_write(vc4_state,
190 			VC4_SET_FIELD(format->has_alpha ?
191 				      SCALER_POS2_ALPHA_MODE_PIPELINE :
192 				      SCALER_POS2_ALPHA_MODE_FIXED,
193 				      SCALER_POS2_ALPHA_MODE) |
194 			VC4_SET_FIELD(crtc_w, SCALER_POS2_WIDTH) |
195 			VC4_SET_FIELD(crtc_h, SCALER_POS2_HEIGHT));
196 
197 	/* Position Word 3: Context.  Written by the HVS. */
198 	vc4_dlist_write(vc4_state, 0xc0c0c0c0);
199 
200 	/* Pointer Word 0: RGB / Y Pointer */
201 	vc4_dlist_write(vc4_state, bo->paddr + offset);
202 
203 	/* Pointer Context Word 0: Written by the HVS */
204 	vc4_dlist_write(vc4_state, 0xc0c0c0c0);
205 
206 	/* Pitch word 0: Pointer 0 Pitch */
207 	vc4_dlist_write(vc4_state,
208 			VC4_SET_FIELD(fb->pitches[0], SCALER_SRC_PITCH));
209 
210 	vc4_state->dlist[ctl0_offset] |=
211 		VC4_SET_FIELD(vc4_state->dlist_count, SCALER_CTL0_SIZE);
212 
213 	return 0;
214 }
215 
216 /* If a modeset involves changing the setup of a plane, the atomic
217  * infrastructure will call this to validate a proposed plane setup.
218  * However, if a plane isn't getting updated, this (and the
219  * corresponding vc4_plane_atomic_update) won't get called.  Thus, we
220  * compute the dlist here and have all active plane dlists get updated
221  * in the CRTC's flush.
222  */
223 static int vc4_plane_atomic_check(struct drm_plane *plane,
224 				  struct drm_plane_state *state)
225 {
226 	struct vc4_plane_state *vc4_state = to_vc4_plane_state(state);
227 
228 	vc4_state->dlist_count = 0;
229 
230 	if (plane_enabled(state))
231 		return vc4_plane_mode_set(plane, state);
232 	else
233 		return 0;
234 }
235 
236 static void vc4_plane_atomic_update(struct drm_plane *plane,
237 				    struct drm_plane_state *old_state)
238 {
239 	/* No contents here.  Since we don't know where in the CRTC's
240 	 * dlist we should be stored, our dlist is uploaded to the
241 	 * hardware with vc4_plane_write_dlist() at CRTC atomic_flush
242 	 * time.
243 	 */
244 }
245 
246 u32 vc4_plane_write_dlist(struct drm_plane *plane, u32 __iomem *dlist)
247 {
248 	struct vc4_plane_state *vc4_state = to_vc4_plane_state(plane->state);
249 	int i;
250 
251 	/* Can't memcpy_toio() because it needs to be 32-bit writes. */
252 	for (i = 0; i < vc4_state->dlist_count; i++)
253 		writel(vc4_state->dlist[i], &dlist[i]);
254 
255 	return vc4_state->dlist_count;
256 }
257 
258 u32 vc4_plane_dlist_size(struct drm_plane_state *state)
259 {
260 	struct vc4_plane_state *vc4_state = to_vc4_plane_state(state);
261 
262 	return vc4_state->dlist_count;
263 }
264 
265 static const struct drm_plane_helper_funcs vc4_plane_helper_funcs = {
266 	.prepare_fb = NULL,
267 	.cleanup_fb = NULL,
268 	.atomic_check = vc4_plane_atomic_check,
269 	.atomic_update = vc4_plane_atomic_update,
270 };
271 
272 static void vc4_plane_destroy(struct drm_plane *plane)
273 {
274 	drm_plane_helper_disable(plane);
275 	drm_plane_cleanup(plane);
276 }
277 
278 static const struct drm_plane_funcs vc4_plane_funcs = {
279 	.update_plane = drm_atomic_helper_update_plane,
280 	.disable_plane = drm_atomic_helper_disable_plane,
281 	.destroy = vc4_plane_destroy,
282 	.set_property = NULL,
283 	.reset = vc4_plane_reset,
284 	.atomic_duplicate_state = vc4_plane_duplicate_state,
285 	.atomic_destroy_state = vc4_plane_destroy_state,
286 };
287 
288 struct drm_plane *vc4_plane_init(struct drm_device *dev,
289 				 enum drm_plane_type type)
290 {
291 	struct drm_plane *plane = NULL;
292 	struct vc4_plane *vc4_plane;
293 	u32 formats[ARRAY_SIZE(hvs_formats)];
294 	int ret = 0;
295 	unsigned i;
296 
297 	vc4_plane = devm_kzalloc(dev->dev, sizeof(*vc4_plane),
298 				 GFP_KERNEL);
299 	if (!vc4_plane) {
300 		ret = -ENOMEM;
301 		goto fail;
302 	}
303 
304 	for (i = 0; i < ARRAY_SIZE(hvs_formats); i++)
305 		formats[i] = hvs_formats[i].drm;
306 	plane = &vc4_plane->base;
307 	ret = drm_universal_plane_init(dev, plane, 0xff,
308 				       &vc4_plane_funcs,
309 				       formats, ARRAY_SIZE(formats),
310 				       type);
311 
312 	drm_plane_helper_add(plane, &vc4_plane_helper_funcs);
313 
314 	return plane;
315 fail:
316 	if (plane)
317 		vc4_plane_destroy(plane);
318 
319 	return ERR_PTR(ret);
320 }
321