1 // SPDX-License-Identifier: GPL-2.0+
2
3 /*
4 * Copyright 2020 NXP
5 */
6
7 #include <linux/bitfield.h>
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 #include <linux/media-bus-format.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_graph.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17
18 #include <drm/drm_atomic_state_helper.h>
19 #include <drm/drm_bridge.h>
20 #include <drm/drm_print.h>
21
22 #define PC_CTRL_REG 0x0
23 #define PC_COMBINE_ENABLE BIT(0)
24 #define PC_DISP_BYPASS(n) BIT(1 + 21 * (n))
25 #define PC_DISP_HSYNC_POLARITY(n) BIT(2 + 11 * (n))
26 #define PC_DISP_HSYNC_POLARITY_POS(n) DISP_HSYNC_POLARITY(n)
27 #define PC_DISP_VSYNC_POLARITY(n) BIT(3 + 11 * (n))
28 #define PC_DISP_VSYNC_POLARITY_POS(n) DISP_VSYNC_POLARITY(n)
29 #define PC_DISP_DVALID_POLARITY(n) BIT(4 + 11 * (n))
30 #define PC_DISP_DVALID_POLARITY_POS(n) DISP_DVALID_POLARITY(n)
31 #define PC_VSYNC_MASK_ENABLE BIT(5)
32 #define PC_SKIP_MODE BIT(6)
33 #define PC_SKIP_NUMBER_MASK GENMASK(12, 7)
34 #define PC_SKIP_NUMBER(n) FIELD_PREP(PC_SKIP_NUMBER_MASK, (n))
35 #define PC_DISP0_PIX_DATA_FORMAT_MASK GENMASK(18, 16)
36 #define PC_DISP0_PIX_DATA_FORMAT(fmt) \
37 FIELD_PREP(PC_DISP0_PIX_DATA_FORMAT_MASK, (fmt))
38 #define PC_DISP1_PIX_DATA_FORMAT_MASK GENMASK(21, 19)
39 #define PC_DISP1_PIX_DATA_FORMAT(fmt) \
40 FIELD_PREP(PC_DISP1_PIX_DATA_FORMAT_MASK, (fmt))
41
42 #define PC_SW_RESET_REG 0x20
43 #define PC_SW_RESET_N BIT(0)
44 #define PC_DISP_SW_RESET_N(n) BIT(1 + (n))
45 #define PC_FULL_RESET_N (PC_SW_RESET_N | \
46 PC_DISP_SW_RESET_N(0) | \
47 PC_DISP_SW_RESET_N(1))
48
49 #define PC_REG_SET 0x4
50 #define PC_REG_CLR 0x8
51
52 #define DRIVER_NAME "imx8qxp-pixel-combiner"
53
54 enum imx8qxp_pc_pix_data_format {
55 RGB,
56 YUV444,
57 YUV422,
58 SPLIT_RGB,
59 };
60
61 struct imx8qxp_pc_channel {
62 struct drm_bridge bridge;
63 struct drm_bridge *next_bridge;
64 struct imx8qxp_pc *pc;
65 unsigned int stream_id;
66 bool is_available;
67 };
68
69 struct imx8qxp_pc {
70 struct device *dev;
71 struct imx8qxp_pc_channel ch[2];
72 struct clk *clk_apb;
73 void __iomem *base;
74 };
75
imx8qxp_pc_read(struct imx8qxp_pc * pc,unsigned int offset)76 static inline u32 imx8qxp_pc_read(struct imx8qxp_pc *pc, unsigned int offset)
77 {
78 return readl(pc->base + offset);
79 }
80
81 static inline void
imx8qxp_pc_write(struct imx8qxp_pc * pc,unsigned int offset,u32 value)82 imx8qxp_pc_write(struct imx8qxp_pc *pc, unsigned int offset, u32 value)
83 {
84 writel(value, pc->base + offset);
85 }
86
87 static inline void
imx8qxp_pc_write_set(struct imx8qxp_pc * pc,unsigned int offset,u32 value)88 imx8qxp_pc_write_set(struct imx8qxp_pc *pc, unsigned int offset, u32 value)
89 {
90 imx8qxp_pc_write(pc, offset + PC_REG_SET, value);
91 }
92
93 static inline void
imx8qxp_pc_write_clr(struct imx8qxp_pc * pc,unsigned int offset,u32 value)94 imx8qxp_pc_write_clr(struct imx8qxp_pc *pc, unsigned int offset, u32 value)
95 {
96 imx8qxp_pc_write(pc, offset + PC_REG_CLR, value);
97 }
98
99 static enum drm_mode_status
imx8qxp_pc_bridge_mode_valid(struct drm_bridge * bridge,const struct drm_display_info * info,const struct drm_display_mode * mode)100 imx8qxp_pc_bridge_mode_valid(struct drm_bridge *bridge,
101 const struct drm_display_info *info,
102 const struct drm_display_mode *mode)
103 {
104 if (mode->hdisplay > 2560)
105 return MODE_BAD_HVALUE;
106
107 return MODE_OK;
108 }
109
imx8qxp_pc_bridge_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)110 static int imx8qxp_pc_bridge_attach(struct drm_bridge *bridge,
111 enum drm_bridge_attach_flags flags)
112 {
113 struct imx8qxp_pc_channel *ch = bridge->driver_private;
114 struct imx8qxp_pc *pc = ch->pc;
115
116 if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) {
117 DRM_DEV_ERROR(pc->dev,
118 "do not support creating a drm_connector\n");
119 return -EINVAL;
120 }
121
122 return drm_bridge_attach(bridge->encoder,
123 ch->next_bridge, bridge,
124 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
125 }
126
127 static void
imx8qxp_pc_bridge_mode_set(struct drm_bridge * bridge,const struct drm_display_mode * mode,const struct drm_display_mode * adjusted_mode)128 imx8qxp_pc_bridge_mode_set(struct drm_bridge *bridge,
129 const struct drm_display_mode *mode,
130 const struct drm_display_mode *adjusted_mode)
131 {
132 struct imx8qxp_pc_channel *ch = bridge->driver_private;
133 struct imx8qxp_pc *pc = ch->pc;
134 u32 val;
135 int ret;
136
137 ret = pm_runtime_get_sync(pc->dev);
138 if (ret < 0)
139 DRM_DEV_ERROR(pc->dev,
140 "failed to get runtime PM sync: %d\n", ret);
141
142 ret = clk_prepare_enable(pc->clk_apb);
143 if (ret)
144 DRM_DEV_ERROR(pc->dev, "%s: failed to enable apb clock: %d\n",
145 __func__, ret);
146
147 /* HSYNC to pixel link is active low. */
148 imx8qxp_pc_write_clr(pc, PC_CTRL_REG,
149 PC_DISP_HSYNC_POLARITY(ch->stream_id));
150
151 /* VSYNC to pixel link is active low. */
152 imx8qxp_pc_write_clr(pc, PC_CTRL_REG,
153 PC_DISP_VSYNC_POLARITY(ch->stream_id));
154
155 /* Data enable to pixel link is active high. */
156 imx8qxp_pc_write_set(pc, PC_CTRL_REG,
157 PC_DISP_DVALID_POLARITY(ch->stream_id));
158
159 /* Mask the first frame output which may be incomplete. */
160 imx8qxp_pc_write_set(pc, PC_CTRL_REG, PC_VSYNC_MASK_ENABLE);
161
162 /* Only support RGB currently. */
163 val = imx8qxp_pc_read(pc, PC_CTRL_REG);
164 if (ch->stream_id == 0) {
165 val &= ~PC_DISP0_PIX_DATA_FORMAT_MASK;
166 val |= PC_DISP0_PIX_DATA_FORMAT(RGB);
167 } else {
168 val &= ~PC_DISP1_PIX_DATA_FORMAT_MASK;
169 val |= PC_DISP1_PIX_DATA_FORMAT(RGB);
170 }
171 imx8qxp_pc_write(pc, PC_CTRL_REG, val);
172
173 /* Only support bypass mode currently. */
174 imx8qxp_pc_write_set(pc, PC_CTRL_REG, PC_DISP_BYPASS(ch->stream_id));
175
176 clk_disable_unprepare(pc->clk_apb);
177 }
178
179 static void
imx8qxp_pc_bridge_atomic_disable(struct drm_bridge * bridge,struct drm_bridge_state * old_bridge_state)180 imx8qxp_pc_bridge_atomic_disable(struct drm_bridge *bridge,
181 struct drm_bridge_state *old_bridge_state)
182 {
183 struct imx8qxp_pc_channel *ch = bridge->driver_private;
184 struct imx8qxp_pc *pc = ch->pc;
185 int ret;
186
187 ret = pm_runtime_put(pc->dev);
188 if (ret < 0)
189 DRM_DEV_ERROR(pc->dev, "failed to put runtime PM: %d\n", ret);
190 }
191
192 static const u32 imx8qxp_pc_bus_output_fmts[] = {
193 MEDIA_BUS_FMT_RGB888_1X36_CPADLO,
194 MEDIA_BUS_FMT_RGB666_1X36_CPADLO,
195 };
196
imx8qxp_pc_bus_output_fmt_supported(u32 fmt)197 static bool imx8qxp_pc_bus_output_fmt_supported(u32 fmt)
198 {
199 int i;
200
201 for (i = 0; i < ARRAY_SIZE(imx8qxp_pc_bus_output_fmts); i++) {
202 if (imx8qxp_pc_bus_output_fmts[i] == fmt)
203 return true;
204 }
205
206 return false;
207 }
208
209 static u32 *
imx8qxp_pc_bridge_atomic_get_input_bus_fmts(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state,u32 output_fmt,unsigned int * num_input_fmts)210 imx8qxp_pc_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
211 struct drm_bridge_state *bridge_state,
212 struct drm_crtc_state *crtc_state,
213 struct drm_connector_state *conn_state,
214 u32 output_fmt,
215 unsigned int *num_input_fmts)
216 {
217 u32 *input_fmts;
218
219 if (!imx8qxp_pc_bus_output_fmt_supported(output_fmt))
220 return NULL;
221
222 *num_input_fmts = 1;
223
224 input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
225 if (!input_fmts)
226 return NULL;
227
228 switch (output_fmt) {
229 case MEDIA_BUS_FMT_RGB888_1X36_CPADLO:
230 input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X30_CPADLO;
231 break;
232 case MEDIA_BUS_FMT_RGB666_1X36_CPADLO:
233 input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X30_CPADLO;
234 break;
235 default:
236 kfree(input_fmts);
237 input_fmts = NULL;
238 break;
239 }
240
241 return input_fmts;
242 }
243
244 static u32 *
imx8qxp_pc_bridge_atomic_get_output_bus_fmts(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state,unsigned int * num_output_fmts)245 imx8qxp_pc_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
246 struct drm_bridge_state *bridge_state,
247 struct drm_crtc_state *crtc_state,
248 struct drm_connector_state *conn_state,
249 unsigned int *num_output_fmts)
250 {
251 *num_output_fmts = ARRAY_SIZE(imx8qxp_pc_bus_output_fmts);
252 return kmemdup(imx8qxp_pc_bus_output_fmts,
253 sizeof(imx8qxp_pc_bus_output_fmts), GFP_KERNEL);
254 }
255
256 static const struct drm_bridge_funcs imx8qxp_pc_bridge_funcs = {
257 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
258 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
259 .atomic_reset = drm_atomic_helper_bridge_reset,
260 .mode_valid = imx8qxp_pc_bridge_mode_valid,
261 .attach = imx8qxp_pc_bridge_attach,
262 .mode_set = imx8qxp_pc_bridge_mode_set,
263 .atomic_disable = imx8qxp_pc_bridge_atomic_disable,
264 .atomic_get_input_bus_fmts =
265 imx8qxp_pc_bridge_atomic_get_input_bus_fmts,
266 .atomic_get_output_bus_fmts =
267 imx8qxp_pc_bridge_atomic_get_output_bus_fmts,
268 };
269
imx8qxp_pc_bridge_probe(struct platform_device * pdev)270 static int imx8qxp_pc_bridge_probe(struct platform_device *pdev)
271 {
272 struct imx8qxp_pc *pc;
273 struct imx8qxp_pc_channel *ch;
274 struct device *dev = &pdev->dev;
275 struct device_node *np = dev->of_node;
276 struct device_node *child, *remote;
277 u32 i;
278 int ret;
279
280 pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL);
281 if (!pc)
282 return -ENOMEM;
283
284 pc->base = devm_platform_ioremap_resource(pdev, 0);
285 if (IS_ERR(pc->base))
286 return PTR_ERR(pc->base);
287
288 pc->dev = dev;
289
290 pc->clk_apb = devm_clk_get(dev, "apb");
291 if (IS_ERR(pc->clk_apb)) {
292 ret = PTR_ERR(pc->clk_apb);
293 if (ret != -EPROBE_DEFER)
294 DRM_DEV_ERROR(dev, "failed to get apb clock: %d\n", ret);
295 return ret;
296 }
297
298 platform_set_drvdata(pdev, pc);
299 pm_runtime_enable(dev);
300
301 for_each_available_child_of_node(np, child) {
302 ret = of_property_read_u32(child, "reg", &i);
303 if (ret || i > 1) {
304 ret = -EINVAL;
305 DRM_DEV_ERROR(dev,
306 "invalid channel(%u) node address\n", i);
307 goto free_child;
308 }
309
310 ch = &pc->ch[i];
311 ch->pc = pc;
312 ch->stream_id = i;
313
314 remote = of_graph_get_remote_node(child, 1, 0);
315 if (!remote) {
316 ret = -ENODEV;
317 DRM_DEV_ERROR(dev,
318 "channel%u failed to get port1's remote node: %d\n",
319 i, ret);
320 goto free_child;
321 }
322
323 ch->next_bridge = of_drm_find_bridge(remote);
324 if (!ch->next_bridge) {
325 of_node_put(remote);
326 ret = -EPROBE_DEFER;
327 DRM_DEV_DEBUG_DRIVER(dev,
328 "channel%u failed to find next bridge: %d\n",
329 i, ret);
330 goto free_child;
331 }
332
333 of_node_put(remote);
334
335 ch->bridge.driver_private = ch;
336 ch->bridge.funcs = &imx8qxp_pc_bridge_funcs;
337 ch->bridge.of_node = child;
338 ch->is_available = true;
339
340 drm_bridge_add(&ch->bridge);
341 }
342
343 return 0;
344
345 free_child:
346 of_node_put(child);
347
348 if (i == 1 && pc->ch[0].next_bridge)
349 drm_bridge_remove(&pc->ch[0].bridge);
350
351 pm_runtime_disable(dev);
352 return ret;
353 }
354
imx8qxp_pc_bridge_remove(struct platform_device * pdev)355 static void imx8qxp_pc_bridge_remove(struct platform_device *pdev)
356 {
357 struct imx8qxp_pc *pc = platform_get_drvdata(pdev);
358 struct imx8qxp_pc_channel *ch;
359 int i;
360
361 for (i = 0; i < 2; i++) {
362 ch = &pc->ch[i];
363
364 if (!ch->is_available)
365 continue;
366
367 drm_bridge_remove(&ch->bridge);
368 ch->is_available = false;
369 }
370
371 pm_runtime_disable(&pdev->dev);
372 }
373
imx8qxp_pc_runtime_suspend(struct device * dev)374 static int imx8qxp_pc_runtime_suspend(struct device *dev)
375 {
376 struct platform_device *pdev = to_platform_device(dev);
377 struct imx8qxp_pc *pc = platform_get_drvdata(pdev);
378 int ret;
379
380 ret = clk_prepare_enable(pc->clk_apb);
381 if (ret)
382 DRM_DEV_ERROR(pc->dev, "%s: failed to enable apb clock: %d\n",
383 __func__, ret);
384
385 /* Disable pixel combiner by full reset. */
386 imx8qxp_pc_write_clr(pc, PC_SW_RESET_REG, PC_FULL_RESET_N);
387
388 clk_disable_unprepare(pc->clk_apb);
389
390 /* Ensure the reset takes effect. */
391 usleep_range(10, 20);
392
393 return ret;
394 }
395
imx8qxp_pc_runtime_resume(struct device * dev)396 static int imx8qxp_pc_runtime_resume(struct device *dev)
397 {
398 struct platform_device *pdev = to_platform_device(dev);
399 struct imx8qxp_pc *pc = platform_get_drvdata(pdev);
400 int ret;
401
402 ret = clk_prepare_enable(pc->clk_apb);
403 if (ret) {
404 DRM_DEV_ERROR(pc->dev, "%s: failed to enable apb clock: %d\n",
405 __func__, ret);
406 return ret;
407 }
408
409 /* out of reset */
410 imx8qxp_pc_write_set(pc, PC_SW_RESET_REG, PC_FULL_RESET_N);
411
412 clk_disable_unprepare(pc->clk_apb);
413
414 return ret;
415 }
416
417 static const struct dev_pm_ops imx8qxp_pc_pm_ops = {
418 RUNTIME_PM_OPS(imx8qxp_pc_runtime_suspend, imx8qxp_pc_runtime_resume, NULL)
419 };
420
421 static const struct of_device_id imx8qxp_pc_dt_ids[] = {
422 { .compatible = "fsl,imx8qm-pixel-combiner", },
423 { .compatible = "fsl,imx8qxp-pixel-combiner", },
424 { /* sentinel */ }
425 };
426 MODULE_DEVICE_TABLE(of, imx8qxp_pc_dt_ids);
427
428 static struct platform_driver imx8qxp_pc_bridge_driver = {
429 .probe = imx8qxp_pc_bridge_probe,
430 .remove = imx8qxp_pc_bridge_remove,
431 .driver = {
432 .pm = pm_ptr(&imx8qxp_pc_pm_ops),
433 .name = DRIVER_NAME,
434 .of_match_table = imx8qxp_pc_dt_ids,
435 },
436 };
437 module_platform_driver(imx8qxp_pc_bridge_driver);
438
439 MODULE_DESCRIPTION("i.MX8QM/QXP pixel combiner bridge driver");
440 MODULE_AUTHOR("Liu Ying <victor.liu@nxp.com>");
441 MODULE_LICENSE("GPL v2");
442 MODULE_ALIAS("platform:" DRIVER_NAME);
443