xref: /openbmc/linux/drivers/gpu/drm/mcde/mcde_drv.c (revision d9fd5a71)
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 	struct resource *res;
280 	u32 pid;
281 	int irq;
282 	int ret;
283 	int i;
284 
285 	mcde = devm_drm_dev_alloc(dev, &mcde_drm_driver, struct mcde, drm);
286 	if (IS_ERR(mcde))
287 		return PTR_ERR(mcde);
288 	drm = &mcde->drm;
289 	mcde->dev = dev;
290 	platform_set_drvdata(pdev, drm);
291 
292 	/* First obtain and turn on the main power */
293 	mcde->epod = devm_regulator_get(dev, "epod");
294 	if (IS_ERR(mcde->epod)) {
295 		ret = PTR_ERR(mcde->epod);
296 		dev_err(dev, "can't get EPOD regulator\n");
297 		return ret;
298 	}
299 	ret = regulator_enable(mcde->epod);
300 	if (ret) {
301 		dev_err(dev, "can't enable EPOD regulator\n");
302 		return ret;
303 	}
304 	mcde->vana = devm_regulator_get(dev, "vana");
305 	if (IS_ERR(mcde->vana)) {
306 		ret = PTR_ERR(mcde->vana);
307 		dev_err(dev, "can't get VANA regulator\n");
308 		goto regulator_epod_off;
309 	}
310 	ret = regulator_enable(mcde->vana);
311 	if (ret) {
312 		dev_err(dev, "can't enable VANA regulator\n");
313 		goto regulator_epod_off;
314 	}
315 	/*
316 	 * The vendor code uses ESRAM (onchip RAM) and need to activate
317 	 * the v-esram34 regulator, but we don't use that yet
318 	 */
319 
320 	/* Clock the silicon so we can access the registers */
321 	mcde->mcde_clk = devm_clk_get(dev, "mcde");
322 	if (IS_ERR(mcde->mcde_clk)) {
323 		dev_err(dev, "unable to get MCDE main clock\n");
324 		ret = PTR_ERR(mcde->mcde_clk);
325 		goto regulator_off;
326 	}
327 	ret = clk_prepare_enable(mcde->mcde_clk);
328 	if (ret) {
329 		dev_err(dev, "failed to enable MCDE main clock\n");
330 		goto regulator_off;
331 	}
332 	dev_info(dev, "MCDE clk rate %lu Hz\n", clk_get_rate(mcde->mcde_clk));
333 
334 	mcde->lcd_clk = devm_clk_get(dev, "lcd");
335 	if (IS_ERR(mcde->lcd_clk)) {
336 		dev_err(dev, "unable to get LCD clock\n");
337 		ret = PTR_ERR(mcde->lcd_clk);
338 		goto clk_disable;
339 	}
340 	mcde->hdmi_clk = devm_clk_get(dev, "hdmi");
341 	if (IS_ERR(mcde->hdmi_clk)) {
342 		dev_err(dev, "unable to get HDMI clock\n");
343 		ret = PTR_ERR(mcde->hdmi_clk);
344 		goto clk_disable;
345 	}
346 
347 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
348 	mcde->regs = devm_ioremap_resource(dev, res);
349 	if (IS_ERR(mcde->regs)) {
350 		dev_err(dev, "no MCDE regs\n");
351 		ret = -EINVAL;
352 		goto clk_disable;
353 	}
354 
355 	irq = platform_get_irq(pdev, 0);
356 	if (irq < 0) {
357 		ret = irq;
358 		goto clk_disable;
359 	}
360 
361 	ret = devm_request_irq(dev, irq, mcde_irq, 0, "mcde", mcde);
362 	if (ret) {
363 		dev_err(dev, "failed to request irq %d\n", ret);
364 		goto clk_disable;
365 	}
366 
367 	/*
368 	 * Check hardware revision, we only support U8500v2 version
369 	 * as this was the only version used for mass market deployment,
370 	 * but surely you can add more versions if you have them and
371 	 * need them.
372 	 */
373 	pid = readl(mcde->regs + MCDE_PID);
374 	dev_info(dev, "found MCDE HW revision %d.%d (dev %d, metal fix %d)\n",
375 		 (pid & MCDE_PID_MAJOR_VERSION_MASK)
376 		 >> MCDE_PID_MAJOR_VERSION_SHIFT,
377 		 (pid & MCDE_PID_MINOR_VERSION_MASK)
378 		 >> MCDE_PID_MINOR_VERSION_SHIFT,
379 		 (pid & MCDE_PID_DEVELOPMENT_VERSION_MASK)
380 		 >> MCDE_PID_DEVELOPMENT_VERSION_SHIFT,
381 		 (pid & MCDE_PID_METALFIX_VERSION_MASK)
382 		 >> MCDE_PID_METALFIX_VERSION_SHIFT);
383 	if (pid != 0x03000800) {
384 		dev_err(dev, "unsupported hardware revision\n");
385 		ret = -ENODEV;
386 		goto clk_disable;
387 	}
388 
389 	/* Disable and clear any pending interrupts */
390 	mcde_display_disable_irqs(mcde);
391 	writel(0, mcde->regs + MCDE_IMSCERR);
392 	writel(0xFFFFFFFF, mcde->regs + MCDE_RISERR);
393 
394 	/* Spawn child devices for the DSI ports */
395 	devm_of_platform_populate(dev);
396 
397 	/* Create something that will match the subdrivers when we bind */
398 	for (i = 0; i < ARRAY_SIZE(mcde_component_drivers); i++) {
399 		struct device_driver *drv = &mcde_component_drivers[i]->driver;
400 		struct device *p = NULL, *d;
401 
402 		while ((d = platform_find_device_by_driver(p, drv))) {
403 			put_device(p);
404 			component_match_add(dev, &match, mcde_compare_dev, d);
405 			p = d;
406 		}
407 		put_device(p);
408 	}
409 	if (!match) {
410 		dev_err(dev, "no matching components\n");
411 		ret = -ENODEV;
412 		goto clk_disable;
413 	}
414 	if (IS_ERR(match)) {
415 		dev_err(dev, "could not create component match\n");
416 		ret = PTR_ERR(match);
417 		goto clk_disable;
418 	}
419 
420 	/*
421 	 * Perform an invasive reset of the MCDE and all blocks by
422 	 * cutting the power to the subsystem, then bring it back up
423 	 * later when we enable the display as a result of
424 	 * component_master_add_with_match().
425 	 */
426 	ret = regulator_disable(mcde->epod);
427 	if (ret) {
428 		dev_err(dev, "can't disable EPOD regulator\n");
429 		return ret;
430 	}
431 	/* Wait 50 ms so we are sure we cut the power */
432 	usleep_range(50000, 70000);
433 
434 	ret = component_master_add_with_match(&pdev->dev, &mcde_drm_comp_ops,
435 					      match);
436 	if (ret) {
437 		dev_err(dev, "failed to add component master\n");
438 		/*
439 		 * The EPOD regulator is already disabled at this point so some
440 		 * special errorpath code is needed
441 		 */
442 		clk_disable_unprepare(mcde->mcde_clk);
443 		regulator_disable(mcde->vana);
444 		return ret;
445 	}
446 
447 	return 0;
448 
449 clk_disable:
450 	clk_disable_unprepare(mcde->mcde_clk);
451 regulator_off:
452 	regulator_disable(mcde->vana);
453 regulator_epod_off:
454 	regulator_disable(mcde->epod);
455 	return ret;
456 
457 }
458 
459 static int mcde_remove(struct platform_device *pdev)
460 {
461 	struct drm_device *drm = platform_get_drvdata(pdev);
462 	struct mcde *mcde = to_mcde(drm);
463 
464 	component_master_del(&pdev->dev, &mcde_drm_comp_ops);
465 	clk_disable_unprepare(mcde->mcde_clk);
466 	regulator_disable(mcde->vana);
467 	regulator_disable(mcde->epod);
468 
469 	return 0;
470 }
471 
472 static const struct of_device_id mcde_of_match[] = {
473 	{
474 		.compatible = "ste,mcde",
475 	},
476 	{},
477 };
478 
479 static struct platform_driver mcde_driver = {
480 	.driver = {
481 		.name           = "mcde",
482 		.of_match_table = of_match_ptr(mcde_of_match),
483 	},
484 	.probe = mcde_probe,
485 	.remove = mcde_remove,
486 };
487 
488 static struct platform_driver *const component_drivers[] = {
489 	&mcde_dsi_driver,
490 };
491 
492 static int __init mcde_drm_register(void)
493 {
494 	int ret;
495 
496 	ret = platform_register_drivers(component_drivers,
497 					ARRAY_SIZE(component_drivers));
498 	if (ret)
499 		return ret;
500 
501 	return platform_driver_register(&mcde_driver);
502 }
503 
504 static void __exit mcde_drm_unregister(void)
505 {
506 	platform_unregister_drivers(component_drivers,
507 				    ARRAY_SIZE(component_drivers));
508 	platform_driver_unregister(&mcde_driver);
509 }
510 
511 module_init(mcde_drm_register);
512 module_exit(mcde_drm_unregister);
513 
514 MODULE_ALIAS("platform:mcde-drm");
515 MODULE_DESCRIPTION(DRIVER_DESC);
516 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
517 MODULE_LICENSE("GPL");
518