xref: /openbmc/linux/drivers/gpu/drm/mcde/mcde_drv.c (revision c4a11bf4)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2018 Linus Walleij <linus.walleij@linaro.org>
4  * Parts of this file were based on the MCDE driver by Marcus Lorentzon
5  * (C) ST-Ericsson SA 2013
6  */
7 
8 /**
9  * DOC: ST-Ericsson MCDE Driver
10  *
11  * The MCDE (short for multi-channel display engine) is a graphics
12  * controller found in the Ux500 chipsets, such as NovaThor U8500.
13  * It was initially conceptualized by ST Microelectronics for the
14  * successor of the Nomadik line, STn8500 but productified in the
15  * ST-Ericsson U8500 where is was used for mass-market deployments
16  * in Android phones from Samsung and Sony Ericsson.
17  *
18  * It can do 1080p30 on SDTV CCIR656, DPI-2, DBI-2 or DSI for
19  * panels with or without frame buffering and can convert most
20  * input formats including most variants of RGB and YUV.
21  *
22  * The hardware has four display pipes, and the layout is a little
23  * bit like this::
24  *
25  *   Memory     -> Overlay -> Channel -> FIFO -> 8 formatters -> DSI/DPI
26  *   External      0..5       0..3       A,B,    6 x DSI         bridge
27  *   source 0..9                         C0,C1   2 x DPI
28  *
29  * FIFOs A and B are for LCD and HDMI while FIFO CO/C1 are for
30  * panels with embedded buffer.
31  * 6 of the formatters are for DSI, 3 pairs for VID/CMD respectively.
32  * 2 of the formatters are for DPI.
33  *
34  * Behind the formatters are the DSI or DPI ports that route to
35  * the external pins of the chip. As there are 3 DSI ports and one
36  * DPI port, it is possible to configure up to 4 display pipelines
37  * (effectively using channels 0..3) for concurrent use.
38  *
39  * In the current DRM/KMS setup, we use one external source, one overlay,
40  * one FIFO and one formatter which we connect to the simple CMA framebuffer
41  * helpers. We then provide a bridge to the DSI port, and on the DSI port
42  * bridge we connect hang a panel bridge or other bridge. This may be subject
43  * to change as we exploit more of the hardware capabilities.
44  *
45  * TODO:
46  *
47  * - Enabled damaged rectangles using drm_plane_enable_fb_damage_clips()
48  *   so we can selectively just transmit the damaged area to a
49  *   command-only display.
50  * - Enable mixing of more planes, possibly at the cost of moving away
51  *   from using the simple framebuffer pipeline.
52  * - Enable output to bridges such as the AV8100 HDMI encoder from
53  *   the DSI bridge.
54  */
55 
56 #include <linux/clk.h>
57 #include <linux/component.h>
58 #include <linux/dma-buf.h>
59 #include <linux/irq.h>
60 #include <linux/io.h>
61 #include <linux/module.h>
62 #include <linux/of_platform.h>
63 #include <linux/platform_device.h>
64 #include <linux/regulator/consumer.h>
65 #include <linux/slab.h>
66 #include <linux/delay.h>
67 
68 #include <drm/drm_atomic_helper.h>
69 #include <drm/drm_bridge.h>
70 #include <drm/drm_drv.h>
71 #include <drm/drm_fb_cma_helper.h>
72 #include <drm/drm_fb_helper.h>
73 #include <drm/drm_gem.h>
74 #include <drm/drm_gem_cma_helper.h>
75 #include <drm/drm_gem_framebuffer_helper.h>
76 #include <drm/drm_managed.h>
77 #include <drm/drm_of.h>
78 #include <drm/drm_probe_helper.h>
79 #include <drm/drm_panel.h>
80 #include <drm/drm_vblank.h>
81 
82 #include "mcde_drm.h"
83 
84 #define DRIVER_DESC	"DRM module for MCDE"
85 
86 #define MCDE_PID 0x000001FC
87 #define MCDE_PID_METALFIX_VERSION_SHIFT 0
88 #define MCDE_PID_METALFIX_VERSION_MASK 0x000000FF
89 #define MCDE_PID_DEVELOPMENT_VERSION_SHIFT 8
90 #define MCDE_PID_DEVELOPMENT_VERSION_MASK 0x0000FF00
91 #define MCDE_PID_MINOR_VERSION_SHIFT 16
92 #define MCDE_PID_MINOR_VERSION_MASK 0x00FF0000
93 #define MCDE_PID_MAJOR_VERSION_SHIFT 24
94 #define MCDE_PID_MAJOR_VERSION_MASK 0xFF000000
95 
96 static const struct drm_mode_config_funcs mcde_mode_config_funcs = {
97 	.fb_create = drm_gem_fb_create_with_dirty,
98 	.atomic_check = drm_atomic_helper_check,
99 	.atomic_commit = drm_atomic_helper_commit,
100 };
101 
102 static const struct drm_mode_config_helper_funcs mcde_mode_config_helpers = {
103 	/*
104 	 * Using this function is necessary to commit atomic updates
105 	 * that need the CRTC to be enabled before a commit, as is
106 	 * the case with e.g. DSI displays.
107 	 */
108 	.atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
109 };
110 
111 static irqreturn_t mcde_irq(int irq, void *data)
112 {
113 	struct mcde *mcde = data;
114 	u32 val;
115 
116 	val = readl(mcde->regs + MCDE_MISERR);
117 
118 	mcde_display_irq(mcde);
119 
120 	if (val)
121 		dev_info(mcde->dev, "some error IRQ\n");
122 	writel(val, mcde->regs + MCDE_RISERR);
123 
124 	return IRQ_HANDLED;
125 }
126 
127 static int mcde_modeset_init(struct drm_device *drm)
128 {
129 	struct drm_mode_config *mode_config;
130 	struct mcde *mcde = to_mcde(drm);
131 	int ret;
132 
133 	/*
134 	 * If no other bridge was found, check if we have a DPI panel or
135 	 * any other bridge connected directly to the MCDE DPI output.
136 	 * If a DSI bridge is found, DSI will take precedence.
137 	 *
138 	 * TODO: more elaborate bridge selection if we have more than one
139 	 * thing attached to the system.
140 	 */
141 	if (!mcde->bridge) {
142 		struct drm_panel *panel;
143 		struct drm_bridge *bridge;
144 
145 		ret = drm_of_find_panel_or_bridge(drm->dev->of_node,
146 						  0, 0, &panel, &bridge);
147 		if (ret) {
148 			dev_err(drm->dev,
149 				"Could not locate any output bridge or panel\n");
150 			return ret;
151 		}
152 		if (panel) {
153 			bridge = drm_panel_bridge_add_typed(panel,
154 					DRM_MODE_CONNECTOR_DPI);
155 			if (IS_ERR(bridge)) {
156 				dev_err(drm->dev,
157 					"Could not connect panel bridge\n");
158 				return PTR_ERR(bridge);
159 			}
160 		}
161 		mcde->dpi_output = true;
162 		mcde->bridge = bridge;
163 		mcde->flow_mode = MCDE_DPI_FORMATTER_FLOW;
164 	}
165 
166 	mode_config = &drm->mode_config;
167 	mode_config->funcs = &mcde_mode_config_funcs;
168 	mode_config->helper_private = &mcde_mode_config_helpers;
169 	/* This hardware can do 1080p */
170 	mode_config->min_width = 1;
171 	mode_config->max_width = 1920;
172 	mode_config->min_height = 1;
173 	mode_config->max_height = 1080;
174 
175 	ret = drm_vblank_init(drm, 1);
176 	if (ret) {
177 		dev_err(drm->dev, "failed to init vblank\n");
178 		return ret;
179 	}
180 
181 	ret = mcde_display_init(drm);
182 	if (ret) {
183 		dev_err(drm->dev, "failed to init display\n");
184 		return ret;
185 	}
186 
187 	/* Attach the bridge. */
188 	ret = drm_simple_display_pipe_attach_bridge(&mcde->pipe,
189 						    mcde->bridge);
190 	if (ret) {
191 		dev_err(drm->dev, "failed to attach display output bridge\n");
192 		return ret;
193 	}
194 
195 	drm_mode_config_reset(drm);
196 	drm_kms_helper_poll_init(drm);
197 
198 	return 0;
199 }
200 
201 DEFINE_DRM_GEM_CMA_FOPS(drm_fops);
202 
203 static const struct drm_driver mcde_drm_driver = {
204 	.driver_features =
205 		DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
206 	.lastclose = drm_fb_helper_lastclose,
207 	.ioctls = NULL,
208 	.fops = &drm_fops,
209 	.name = "mcde",
210 	.desc = DRIVER_DESC,
211 	.date = "20180529",
212 	.major = 1,
213 	.minor = 0,
214 	.patchlevel = 0,
215 	DRM_GEM_CMA_DRIVER_OPS,
216 };
217 
218 static int mcde_drm_bind(struct device *dev)
219 {
220 	struct drm_device *drm = dev_get_drvdata(dev);
221 	int ret;
222 
223 	ret = drmm_mode_config_init(drm);
224 	if (ret)
225 		return ret;
226 
227 	ret = component_bind_all(drm->dev, drm);
228 	if (ret) {
229 		dev_err(dev, "can't bind component devices\n");
230 		return ret;
231 	}
232 
233 	ret = mcde_modeset_init(drm);
234 	if (ret)
235 		goto unbind;
236 
237 	ret = drm_dev_register(drm, 0);
238 	if (ret < 0)
239 		goto unbind;
240 
241 	drm_fbdev_generic_setup(drm, 32);
242 
243 	return 0;
244 
245 unbind:
246 	component_unbind_all(drm->dev, drm);
247 	return ret;
248 }
249 
250 static void mcde_drm_unbind(struct device *dev)
251 {
252 	struct drm_device *drm = dev_get_drvdata(dev);
253 
254 	drm_dev_unregister(drm);
255 	drm_atomic_helper_shutdown(drm);
256 	component_unbind_all(drm->dev, drm);
257 }
258 
259 static const struct component_master_ops mcde_drm_comp_ops = {
260 	.bind = mcde_drm_bind,
261 	.unbind = mcde_drm_unbind,
262 };
263 
264 static struct platform_driver *const mcde_component_drivers[] = {
265 	&mcde_dsi_driver,
266 };
267 
268 static int mcde_compare_dev(struct device *dev, void *data)
269 {
270 	return dev == data;
271 }
272 
273 static int mcde_probe(struct platform_device *pdev)
274 {
275 	struct device *dev = &pdev->dev;
276 	struct drm_device *drm;
277 	struct mcde *mcde;
278 	struct component_match *match = NULL;
279 	u32 pid;
280 	int irq;
281 	int ret;
282 	int i;
283 
284 	mcde = devm_drm_dev_alloc(dev, &mcde_drm_driver, struct mcde, drm);
285 	if (IS_ERR(mcde))
286 		return PTR_ERR(mcde);
287 	drm = &mcde->drm;
288 	mcde->dev = dev;
289 	platform_set_drvdata(pdev, drm);
290 
291 	/* First obtain and turn on the main power */
292 	mcde->epod = devm_regulator_get(dev, "epod");
293 	if (IS_ERR(mcde->epod)) {
294 		ret = PTR_ERR(mcde->epod);
295 		dev_err(dev, "can't get EPOD regulator\n");
296 		return ret;
297 	}
298 	ret = regulator_enable(mcde->epod);
299 	if (ret) {
300 		dev_err(dev, "can't enable EPOD regulator\n");
301 		return ret;
302 	}
303 	mcde->vana = devm_regulator_get(dev, "vana");
304 	if (IS_ERR(mcde->vana)) {
305 		ret = PTR_ERR(mcde->vana);
306 		dev_err(dev, "can't get VANA regulator\n");
307 		goto regulator_epod_off;
308 	}
309 	ret = regulator_enable(mcde->vana);
310 	if (ret) {
311 		dev_err(dev, "can't enable VANA regulator\n");
312 		goto regulator_epod_off;
313 	}
314 	/*
315 	 * The vendor code uses ESRAM (onchip RAM) and need to activate
316 	 * the v-esram34 regulator, but we don't use that yet
317 	 */
318 
319 	/* Clock the silicon so we can access the registers */
320 	mcde->mcde_clk = devm_clk_get(dev, "mcde");
321 	if (IS_ERR(mcde->mcde_clk)) {
322 		dev_err(dev, "unable to get MCDE main clock\n");
323 		ret = PTR_ERR(mcde->mcde_clk);
324 		goto regulator_off;
325 	}
326 	ret = clk_prepare_enable(mcde->mcde_clk);
327 	if (ret) {
328 		dev_err(dev, "failed to enable MCDE main clock\n");
329 		goto regulator_off;
330 	}
331 	dev_info(dev, "MCDE clk rate %lu Hz\n", clk_get_rate(mcde->mcde_clk));
332 
333 	mcde->lcd_clk = devm_clk_get(dev, "lcd");
334 	if (IS_ERR(mcde->lcd_clk)) {
335 		dev_err(dev, "unable to get LCD clock\n");
336 		ret = PTR_ERR(mcde->lcd_clk);
337 		goto clk_disable;
338 	}
339 	mcde->hdmi_clk = devm_clk_get(dev, "hdmi");
340 	if (IS_ERR(mcde->hdmi_clk)) {
341 		dev_err(dev, "unable to get HDMI clock\n");
342 		ret = PTR_ERR(mcde->hdmi_clk);
343 		goto clk_disable;
344 	}
345 
346 	mcde->regs = devm_platform_ioremap_resource(pdev, 0);
347 	if (IS_ERR(mcde->regs)) {
348 		dev_err(dev, "no MCDE regs\n");
349 		ret = -EINVAL;
350 		goto clk_disable;
351 	}
352 
353 	irq = platform_get_irq(pdev, 0);
354 	if (irq < 0) {
355 		ret = irq;
356 		goto clk_disable;
357 	}
358 
359 	ret = devm_request_irq(dev, irq, mcde_irq, 0, "mcde", mcde);
360 	if (ret) {
361 		dev_err(dev, "failed to request irq %d\n", ret);
362 		goto clk_disable;
363 	}
364 
365 	/*
366 	 * Check hardware revision, we only support U8500v2 version
367 	 * as this was the only version used for mass market deployment,
368 	 * but surely you can add more versions if you have them and
369 	 * need them.
370 	 */
371 	pid = readl(mcde->regs + MCDE_PID);
372 	dev_info(dev, "found MCDE HW revision %d.%d (dev %d, metal fix %d)\n",
373 		 (pid & MCDE_PID_MAJOR_VERSION_MASK)
374 		 >> MCDE_PID_MAJOR_VERSION_SHIFT,
375 		 (pid & MCDE_PID_MINOR_VERSION_MASK)
376 		 >> MCDE_PID_MINOR_VERSION_SHIFT,
377 		 (pid & MCDE_PID_DEVELOPMENT_VERSION_MASK)
378 		 >> MCDE_PID_DEVELOPMENT_VERSION_SHIFT,
379 		 (pid & MCDE_PID_METALFIX_VERSION_MASK)
380 		 >> MCDE_PID_METALFIX_VERSION_SHIFT);
381 	if (pid != 0x03000800) {
382 		dev_err(dev, "unsupported hardware revision\n");
383 		ret = -ENODEV;
384 		goto clk_disable;
385 	}
386 
387 	/* Disable and clear any pending interrupts */
388 	mcde_display_disable_irqs(mcde);
389 	writel(0, mcde->regs + MCDE_IMSCERR);
390 	writel(0xFFFFFFFF, mcde->regs + MCDE_RISERR);
391 
392 	/* Spawn child devices for the DSI ports */
393 	devm_of_platform_populate(dev);
394 
395 	/* Create something that will match the subdrivers when we bind */
396 	for (i = 0; i < ARRAY_SIZE(mcde_component_drivers); i++) {
397 		struct device_driver *drv = &mcde_component_drivers[i]->driver;
398 		struct device *p = NULL, *d;
399 
400 		while ((d = platform_find_device_by_driver(p, drv))) {
401 			put_device(p);
402 			component_match_add(dev, &match, mcde_compare_dev, d);
403 			p = d;
404 		}
405 		put_device(p);
406 	}
407 	if (!match) {
408 		dev_err(dev, "no matching components\n");
409 		ret = -ENODEV;
410 		goto clk_disable;
411 	}
412 	if (IS_ERR(match)) {
413 		dev_err(dev, "could not create component match\n");
414 		ret = PTR_ERR(match);
415 		goto clk_disable;
416 	}
417 
418 	/*
419 	 * Perform an invasive reset of the MCDE and all blocks by
420 	 * cutting the power to the subsystem, then bring it back up
421 	 * later when we enable the display as a result of
422 	 * component_master_add_with_match().
423 	 */
424 	ret = regulator_disable(mcde->epod);
425 	if (ret) {
426 		dev_err(dev, "can't disable EPOD regulator\n");
427 		return ret;
428 	}
429 	/* Wait 50 ms so we are sure we cut the power */
430 	usleep_range(50000, 70000);
431 
432 	ret = component_master_add_with_match(&pdev->dev, &mcde_drm_comp_ops,
433 					      match);
434 	if (ret) {
435 		dev_err(dev, "failed to add component master\n");
436 		/*
437 		 * The EPOD regulator is already disabled at this point so some
438 		 * special errorpath code is needed
439 		 */
440 		clk_disable_unprepare(mcde->mcde_clk);
441 		regulator_disable(mcde->vana);
442 		return ret;
443 	}
444 
445 	return 0;
446 
447 clk_disable:
448 	clk_disable_unprepare(mcde->mcde_clk);
449 regulator_off:
450 	regulator_disable(mcde->vana);
451 regulator_epod_off:
452 	regulator_disable(mcde->epod);
453 	return ret;
454 
455 }
456 
457 static int mcde_remove(struct platform_device *pdev)
458 {
459 	struct drm_device *drm = platform_get_drvdata(pdev);
460 	struct mcde *mcde = to_mcde(drm);
461 
462 	component_master_del(&pdev->dev, &mcde_drm_comp_ops);
463 	clk_disable_unprepare(mcde->mcde_clk);
464 	regulator_disable(mcde->vana);
465 	regulator_disable(mcde->epod);
466 
467 	return 0;
468 }
469 
470 static const struct of_device_id mcde_of_match[] = {
471 	{
472 		.compatible = "ste,mcde",
473 	},
474 	{},
475 };
476 
477 static struct platform_driver mcde_driver = {
478 	.driver = {
479 		.name           = "mcde",
480 		.of_match_table = of_match_ptr(mcde_of_match),
481 	},
482 	.probe = mcde_probe,
483 	.remove = mcde_remove,
484 };
485 
486 static struct platform_driver *const component_drivers[] = {
487 	&mcde_dsi_driver,
488 };
489 
490 static int __init mcde_drm_register(void)
491 {
492 	int ret;
493 
494 	ret = platform_register_drivers(component_drivers,
495 					ARRAY_SIZE(component_drivers));
496 	if (ret)
497 		return ret;
498 
499 	return platform_driver_register(&mcde_driver);
500 }
501 
502 static void __exit mcde_drm_unregister(void)
503 {
504 	platform_unregister_drivers(component_drivers,
505 				    ARRAY_SIZE(component_drivers));
506 	platform_driver_unregister(&mcde_driver);
507 }
508 
509 module_init(mcde_drm_register);
510 module_exit(mcde_drm_unregister);
511 
512 MODULE_ALIAS("platform:mcde-drm");
513 MODULE_DESCRIPTION(DRIVER_DESC);
514 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
515 MODULE_LICENSE("GPL");
516