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
mcde_irq(int irq,void * data)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
mcde_modeset_init(struct drm_device * drm)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
mcde_drm_bind(struct device * dev)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
mcde_drm_unbind(struct device * dev)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
mcde_probe(struct platform_device * pdev)268 static int mcde_probe(struct platform_device *pdev)
269 {
270 struct device *dev = &pdev->dev;
271 struct drm_device *drm;
272 struct mcde *mcde;
273 struct component_match *match = NULL;
274 u32 pid;
275 int irq;
276 int ret;
277 int i;
278
279 mcde = devm_drm_dev_alloc(dev, &mcde_drm_driver, struct mcde, drm);
280 if (IS_ERR(mcde))
281 return PTR_ERR(mcde);
282 drm = &mcde->drm;
283 mcde->dev = dev;
284 platform_set_drvdata(pdev, drm);
285
286 /* First obtain and turn on the main power */
287 mcde->epod = devm_regulator_get(dev, "epod");
288 if (IS_ERR(mcde->epod)) {
289 ret = PTR_ERR(mcde->epod);
290 dev_err(dev, "can't get EPOD regulator\n");
291 return ret;
292 }
293 ret = regulator_enable(mcde->epod);
294 if (ret) {
295 dev_err(dev, "can't enable EPOD regulator\n");
296 return ret;
297 }
298 mcde->vana = devm_regulator_get(dev, "vana");
299 if (IS_ERR(mcde->vana)) {
300 ret = PTR_ERR(mcde->vana);
301 dev_err(dev, "can't get VANA regulator\n");
302 goto regulator_epod_off;
303 }
304 ret = regulator_enable(mcde->vana);
305 if (ret) {
306 dev_err(dev, "can't enable VANA regulator\n");
307 goto regulator_epod_off;
308 }
309 /*
310 * The vendor code uses ESRAM (onchip RAM) and need to activate
311 * the v-esram34 regulator, but we don't use that yet
312 */
313
314 /* Clock the silicon so we can access the registers */
315 mcde->mcde_clk = devm_clk_get(dev, "mcde");
316 if (IS_ERR(mcde->mcde_clk)) {
317 dev_err(dev, "unable to get MCDE main clock\n");
318 ret = PTR_ERR(mcde->mcde_clk);
319 goto regulator_off;
320 }
321 ret = clk_prepare_enable(mcde->mcde_clk);
322 if (ret) {
323 dev_err(dev, "failed to enable MCDE main clock\n");
324 goto regulator_off;
325 }
326 dev_info(dev, "MCDE clk rate %lu Hz\n", clk_get_rate(mcde->mcde_clk));
327
328 mcde->lcd_clk = devm_clk_get(dev, "lcd");
329 if (IS_ERR(mcde->lcd_clk)) {
330 dev_err(dev, "unable to get LCD clock\n");
331 ret = PTR_ERR(mcde->lcd_clk);
332 goto clk_disable;
333 }
334 mcde->hdmi_clk = devm_clk_get(dev, "hdmi");
335 if (IS_ERR(mcde->hdmi_clk)) {
336 dev_err(dev, "unable to get HDMI clock\n");
337 ret = PTR_ERR(mcde->hdmi_clk);
338 goto clk_disable;
339 }
340
341 mcde->regs = devm_platform_ioremap_resource(pdev, 0);
342 if (IS_ERR(mcde->regs)) {
343 dev_err(dev, "no MCDE regs\n");
344 ret = -EINVAL;
345 goto clk_disable;
346 }
347
348 irq = platform_get_irq(pdev, 0);
349 if (irq < 0) {
350 ret = irq;
351 goto clk_disable;
352 }
353
354 ret = devm_request_irq(dev, irq, mcde_irq, 0, "mcde", mcde);
355 if (ret) {
356 dev_err(dev, "failed to request irq %d\n", ret);
357 goto clk_disable;
358 }
359
360 /*
361 * Check hardware revision, we only support U8500v2 version
362 * as this was the only version used for mass market deployment,
363 * but surely you can add more versions if you have them and
364 * need them.
365 */
366 pid = readl(mcde->regs + MCDE_PID);
367 dev_info(dev, "found MCDE HW revision %d.%d (dev %d, metal fix %d)\n",
368 (pid & MCDE_PID_MAJOR_VERSION_MASK)
369 >> MCDE_PID_MAJOR_VERSION_SHIFT,
370 (pid & MCDE_PID_MINOR_VERSION_MASK)
371 >> MCDE_PID_MINOR_VERSION_SHIFT,
372 (pid & MCDE_PID_DEVELOPMENT_VERSION_MASK)
373 >> MCDE_PID_DEVELOPMENT_VERSION_SHIFT,
374 (pid & MCDE_PID_METALFIX_VERSION_MASK)
375 >> MCDE_PID_METALFIX_VERSION_SHIFT);
376 if (pid != 0x03000800) {
377 dev_err(dev, "unsupported hardware revision\n");
378 ret = -ENODEV;
379 goto clk_disable;
380 }
381
382 /* Disable and clear any pending interrupts */
383 mcde_display_disable_irqs(mcde);
384 writel(0, mcde->regs + MCDE_IMSCERR);
385 writel(0xFFFFFFFF, mcde->regs + MCDE_RISERR);
386
387 /* Spawn child devices for the DSI ports */
388 devm_of_platform_populate(dev);
389
390 /* Create something that will match the subdrivers when we bind */
391 for (i = 0; i < ARRAY_SIZE(mcde_component_drivers); i++) {
392 struct device_driver *drv = &mcde_component_drivers[i]->driver;
393 struct device *p = NULL, *d;
394
395 while ((d = platform_find_device_by_driver(p, drv))) {
396 put_device(p);
397 component_match_add(dev, &match, component_compare_dev, d);
398 p = d;
399 }
400 put_device(p);
401 }
402 if (!match) {
403 dev_err(dev, "no matching components\n");
404 ret = -ENODEV;
405 goto clk_disable;
406 }
407 if (IS_ERR(match)) {
408 dev_err(dev, "could not create component match\n");
409 ret = PTR_ERR(match);
410 goto clk_disable;
411 }
412
413 /*
414 * Perform an invasive reset of the MCDE and all blocks by
415 * cutting the power to the subsystem, then bring it back up
416 * later when we enable the display as a result of
417 * component_master_add_with_match().
418 */
419 ret = regulator_disable(mcde->epod);
420 if (ret) {
421 dev_err(dev, "can't disable EPOD regulator\n");
422 return ret;
423 }
424 /* Wait 50 ms so we are sure we cut the power */
425 usleep_range(50000, 70000);
426
427 ret = component_master_add_with_match(&pdev->dev, &mcde_drm_comp_ops,
428 match);
429 if (ret) {
430 dev_err(dev, "failed to add component master\n");
431 /*
432 * The EPOD regulator is already disabled at this point so some
433 * special errorpath code is needed
434 */
435 clk_disable_unprepare(mcde->mcde_clk);
436 regulator_disable(mcde->vana);
437 return ret;
438 }
439
440 return 0;
441
442 clk_disable:
443 clk_disable_unprepare(mcde->mcde_clk);
444 regulator_off:
445 regulator_disable(mcde->vana);
446 regulator_epod_off:
447 regulator_disable(mcde->epod);
448 return ret;
449
450 }
451
mcde_remove(struct platform_device * pdev)452 static int mcde_remove(struct platform_device *pdev)
453 {
454 struct drm_device *drm = platform_get_drvdata(pdev);
455 struct mcde *mcde = to_mcde(drm);
456
457 component_master_del(&pdev->dev, &mcde_drm_comp_ops);
458 clk_disable_unprepare(mcde->mcde_clk);
459 regulator_disable(mcde->vana);
460 regulator_disable(mcde->epod);
461
462 return 0;
463 }
464
465 static const struct of_device_id mcde_of_match[] = {
466 {
467 .compatible = "ste,mcde",
468 },
469 {},
470 };
471
472 static struct platform_driver mcde_driver = {
473 .driver = {
474 .name = "mcde",
475 .of_match_table = of_match_ptr(mcde_of_match),
476 },
477 .probe = mcde_probe,
478 .remove = mcde_remove,
479 };
480
481 static struct platform_driver *const component_drivers[] = {
482 &mcde_dsi_driver,
483 };
484
mcde_drm_register(void)485 static int __init mcde_drm_register(void)
486 {
487 int ret;
488
489 if (drm_firmware_drivers_only())
490 return -ENODEV;
491
492 ret = platform_register_drivers(component_drivers,
493 ARRAY_SIZE(component_drivers));
494 if (ret)
495 return ret;
496
497 return platform_driver_register(&mcde_driver);
498 }
499
mcde_drm_unregister(void)500 static void __exit mcde_drm_unregister(void)
501 {
502 platform_unregister_drivers(component_drivers,
503 ARRAY_SIZE(component_drivers));
504 platform_driver_unregister(&mcde_driver);
505 }
506
507 module_init(mcde_drm_register);
508 module_exit(mcde_drm_unregister);
509
510 MODULE_ALIAS("platform:mcde-drm");
511 MODULE_DESCRIPTION(DRIVER_DESC);
512 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
513 MODULE_LICENSE("GPL");
514