xref: /openbmc/linux/drivers/gpu/drm/sti/sti_dvo.c (revision 8730046c)
1 /*
2  * Copyright (C) STMicroelectronics SA 2014
3  * Author: Vincent Abriou <vincent.abriou@st.com> for STMicroelectronics.
4  * License terms:  GNU General Public License (GPL), version 2
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/component.h>
9 #include <linux/debugfs.h>
10 #include <linux/module.h>
11 #include <linux/of_gpio.h>
12 #include <linux/platform_device.h>
13 
14 #include <drm/drmP.h>
15 #include <drm/drm_atomic_helper.h>
16 #include <drm/drm_crtc_helper.h>
17 #include <drm/drm_panel.h>
18 
19 #include "sti_awg_utils.h"
20 #include "sti_drv.h"
21 #include "sti_mixer.h"
22 
23 /* DVO registers */
24 #define DVO_AWG_DIGSYNC_CTRL      0x0000
25 #define DVO_DOF_CFG               0x0004
26 #define DVO_LUT_PROG_LOW          0x0008
27 #define DVO_LUT_PROG_MID          0x000C
28 #define DVO_LUT_PROG_HIGH         0x0010
29 #define DVO_DIGSYNC_INSTR_I       0x0100
30 
31 #define DVO_AWG_CTRL_EN           BIT(0)
32 #define DVO_AWG_FRAME_BASED_SYNC  BIT(2)
33 
34 #define DVO_DOF_EN_LOWBYTE        BIT(0)
35 #define DVO_DOF_EN_MIDBYTE        BIT(1)
36 #define DVO_DOF_EN_HIGHBYTE       BIT(2)
37 #define DVO_DOF_EN                BIT(6)
38 #define DVO_DOF_MOD_COUNT_SHIFT   8
39 
40 #define DVO_LUT_ZERO              0
41 #define DVO_LUT_Y_G               1
42 #define DVO_LUT_Y_G_DEL           2
43 #define DVO_LUT_CB_B              3
44 #define DVO_LUT_CB_B_DEL          4
45 #define DVO_LUT_CR_R              5
46 #define DVO_LUT_CR_R_DEL          6
47 #define DVO_LUT_HOLD              7
48 
49 struct dvo_config {
50 	u32 flags;
51 	u32 lowbyte;
52 	u32 midbyte;
53 	u32 highbyte;
54 	int (*awg_fwgen_fct)(
55 			struct awg_code_generation_params *fw_gen_params,
56 			struct awg_timing *timing);
57 };
58 
59 static struct dvo_config rgb_24bit_de_cfg = {
60 	.flags         = (0L << DVO_DOF_MOD_COUNT_SHIFT),
61 	.lowbyte       = DVO_LUT_CR_R,
62 	.midbyte       = DVO_LUT_Y_G,
63 	.highbyte      = DVO_LUT_CB_B,
64 	.awg_fwgen_fct = sti_awg_generate_code_data_enable_mode,
65 };
66 
67 /**
68  * STI digital video output structure
69  *
70  * @dev: driver device
71  * @drm_dev: pointer to drm device
72  * @mode: current display mode selected
73  * @regs: dvo registers
74  * @clk_pix: pixel clock for dvo
75  * @clk: clock for dvo
76  * @clk_main_parent: dvo parent clock if main path used
77  * @clk_aux_parent: dvo parent clock if aux path used
78  * @panel_node: panel node reference from device tree
79  * @panel: reference to the panel connected to the dvo
80  * @enabled: true if dvo is enabled else false
81  * @encoder: drm_encoder it is bound
82  */
83 struct sti_dvo {
84 	struct device dev;
85 	struct drm_device *drm_dev;
86 	struct drm_display_mode mode;
87 	void __iomem *regs;
88 	struct clk *clk_pix;
89 	struct clk *clk;
90 	struct clk *clk_main_parent;
91 	struct clk *clk_aux_parent;
92 	struct device_node *panel_node;
93 	struct drm_panel *panel;
94 	struct dvo_config *config;
95 	bool enabled;
96 	struct drm_encoder *encoder;
97 	struct drm_bridge *bridge;
98 };
99 
100 struct sti_dvo_connector {
101 	struct drm_connector drm_connector;
102 	struct drm_encoder *encoder;
103 	struct sti_dvo *dvo;
104 };
105 
106 #define to_sti_dvo_connector(x) \
107 	container_of(x, struct sti_dvo_connector, drm_connector)
108 
109 #define BLANKING_LEVEL 16
110 static int dvo_awg_generate_code(struct sti_dvo *dvo, u8 *ram_size, u32 *ram_code)
111 {
112 	struct drm_display_mode *mode = &dvo->mode;
113 	struct dvo_config *config = dvo->config;
114 	struct awg_code_generation_params fw_gen_params;
115 	struct awg_timing timing;
116 
117 	fw_gen_params.ram_code = ram_code;
118 	fw_gen_params.instruction_offset = 0;
119 
120 	timing.total_lines = mode->vtotal;
121 	timing.active_lines = mode->vdisplay;
122 	timing.blanking_lines = mode->vsync_start - mode->vdisplay;
123 	timing.trailing_lines = mode->vtotal - mode->vsync_start;
124 	timing.total_pixels = mode->htotal;
125 	timing.active_pixels = mode->hdisplay;
126 	timing.blanking_pixels = mode->hsync_start - mode->hdisplay;
127 	timing.trailing_pixels = mode->htotal - mode->hsync_start;
128 	timing.blanking_level = BLANKING_LEVEL;
129 
130 	if (config->awg_fwgen_fct(&fw_gen_params, &timing)) {
131 		DRM_ERROR("AWG firmware not properly generated\n");
132 		return -EINVAL;
133 	}
134 
135 	*ram_size = fw_gen_params.instruction_offset;
136 
137 	return 0;
138 }
139 
140 /* Configure AWG, writing instructions
141  *
142  * @dvo: pointer to DVO structure
143  * @awg_ram_code: pointer to AWG instructions table
144  * @nb: nb of AWG instructions
145  */
146 static void dvo_awg_configure(struct sti_dvo *dvo, u32 *awg_ram_code, int nb)
147 {
148 	int i;
149 
150 	DRM_DEBUG_DRIVER("\n");
151 
152 	for (i = 0; i < nb; i++)
153 		writel(awg_ram_code[i],
154 		       dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
155 	for (i = nb; i < AWG_MAX_INST; i++)
156 		writel(0, dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
157 
158 	writel(DVO_AWG_CTRL_EN, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
159 }
160 
161 #define DBGFS_DUMP(reg) seq_printf(s, "\n  %-25s 0x%08X", #reg, \
162 				   readl(dvo->regs + reg))
163 
164 static void dvo_dbg_awg_microcode(struct seq_file *s, void __iomem *reg)
165 {
166 	unsigned int i;
167 
168 	seq_puts(s, "\n\n");
169 	seq_puts(s, "  DVO AWG microcode:");
170 	for (i = 0; i < AWG_MAX_INST; i++) {
171 		if (i % 8 == 0)
172 			seq_printf(s, "\n  %04X:", i);
173 		seq_printf(s, " %04X", readl(reg + i * 4));
174 	}
175 }
176 
177 static int dvo_dbg_show(struct seq_file *s, void *data)
178 {
179 	struct drm_info_node *node = s->private;
180 	struct sti_dvo *dvo = (struct sti_dvo *)node->info_ent->data;
181 
182 	seq_printf(s, "DVO: (vaddr = 0x%p)", dvo->regs);
183 	DBGFS_DUMP(DVO_AWG_DIGSYNC_CTRL);
184 	DBGFS_DUMP(DVO_DOF_CFG);
185 	DBGFS_DUMP(DVO_LUT_PROG_LOW);
186 	DBGFS_DUMP(DVO_LUT_PROG_MID);
187 	DBGFS_DUMP(DVO_LUT_PROG_HIGH);
188 	dvo_dbg_awg_microcode(s, dvo->regs + DVO_DIGSYNC_INSTR_I);
189 	seq_puts(s, "\n");
190 
191 	return 0;
192 }
193 
194 static struct drm_info_list dvo_debugfs_files[] = {
195 	{ "dvo", dvo_dbg_show, 0, NULL },
196 };
197 
198 static void dvo_debugfs_exit(struct sti_dvo *dvo, struct drm_minor *minor)
199 {
200 	drm_debugfs_remove_files(dvo_debugfs_files,
201 				 ARRAY_SIZE(dvo_debugfs_files),
202 				 minor);
203 }
204 
205 static int dvo_debugfs_init(struct sti_dvo *dvo, struct drm_minor *minor)
206 {
207 	unsigned int i;
208 
209 	for (i = 0; i < ARRAY_SIZE(dvo_debugfs_files); i++)
210 		dvo_debugfs_files[i].data = dvo;
211 
212 	return drm_debugfs_create_files(dvo_debugfs_files,
213 					ARRAY_SIZE(dvo_debugfs_files),
214 					minor->debugfs_root, minor);
215 }
216 
217 static void sti_dvo_disable(struct drm_bridge *bridge)
218 {
219 	struct sti_dvo *dvo = bridge->driver_private;
220 
221 	if (!dvo->enabled)
222 		return;
223 
224 	DRM_DEBUG_DRIVER("\n");
225 
226 	if (dvo->config->awg_fwgen_fct)
227 		writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
228 
229 	writel(0x00000000, dvo->regs + DVO_DOF_CFG);
230 
231 	if (dvo->panel)
232 		dvo->panel->funcs->disable(dvo->panel);
233 
234 	/* Disable/unprepare dvo clock */
235 	clk_disable_unprepare(dvo->clk_pix);
236 	clk_disable_unprepare(dvo->clk);
237 
238 	dvo->enabled = false;
239 }
240 
241 static void sti_dvo_pre_enable(struct drm_bridge *bridge)
242 {
243 	struct sti_dvo *dvo = bridge->driver_private;
244 	struct dvo_config *config = dvo->config;
245 	u32 val;
246 
247 	DRM_DEBUG_DRIVER("\n");
248 
249 	if (dvo->enabled)
250 		return;
251 
252 	/* Make sure DVO is disabled */
253 	writel(0x00000000, dvo->regs + DVO_DOF_CFG);
254 	writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
255 
256 	if (config->awg_fwgen_fct) {
257 		u8 nb_instr;
258 		u32 awg_ram_code[AWG_MAX_INST];
259 		/* Configure AWG */
260 		if (!dvo_awg_generate_code(dvo, &nb_instr, awg_ram_code))
261 			dvo_awg_configure(dvo, awg_ram_code, nb_instr);
262 		else
263 			return;
264 	}
265 
266 	/* Prepare/enable clocks */
267 	if (clk_prepare_enable(dvo->clk_pix))
268 		DRM_ERROR("Failed to prepare/enable dvo_pix clk\n");
269 	if (clk_prepare_enable(dvo->clk))
270 		DRM_ERROR("Failed to prepare/enable dvo clk\n");
271 
272 	if (dvo->panel)
273 		dvo->panel->funcs->enable(dvo->panel);
274 
275 	/* Set LUT */
276 	writel(config->lowbyte,  dvo->regs + DVO_LUT_PROG_LOW);
277 	writel(config->midbyte,  dvo->regs + DVO_LUT_PROG_MID);
278 	writel(config->highbyte, dvo->regs + DVO_LUT_PROG_HIGH);
279 
280 	/* Digital output formatter config */
281 	val = (config->flags | DVO_DOF_EN);
282 	writel(val, dvo->regs + DVO_DOF_CFG);
283 
284 	dvo->enabled = true;
285 }
286 
287 static void sti_dvo_set_mode(struct drm_bridge *bridge,
288 			     struct drm_display_mode *mode,
289 			     struct drm_display_mode *adjusted_mode)
290 {
291 	struct sti_dvo *dvo = bridge->driver_private;
292 	struct sti_mixer *mixer = to_sti_mixer(dvo->encoder->crtc);
293 	int rate = mode->clock * 1000;
294 	struct clk *clkp;
295 	int ret;
296 
297 	DRM_DEBUG_DRIVER("\n");
298 
299 	memcpy(&dvo->mode, mode, sizeof(struct drm_display_mode));
300 
301 	/* According to the path used (main or aux), the dvo clocks should
302 	 * have a different parent clock. */
303 	if (mixer->id == STI_MIXER_MAIN)
304 		clkp = dvo->clk_main_parent;
305 	else
306 		clkp = dvo->clk_aux_parent;
307 
308 	if (clkp) {
309 		clk_set_parent(dvo->clk_pix, clkp);
310 		clk_set_parent(dvo->clk, clkp);
311 	}
312 
313 	/* DVO clocks = compositor clock */
314 	ret = clk_set_rate(dvo->clk_pix, rate);
315 	if (ret < 0) {
316 		DRM_ERROR("Cannot set rate (%dHz) for dvo_pix clk\n", rate);
317 		return;
318 	}
319 
320 	ret = clk_set_rate(dvo->clk, rate);
321 	if (ret < 0) {
322 		DRM_ERROR("Cannot set rate (%dHz) for dvo clk\n", rate);
323 		return;
324 	}
325 
326 	/* For now, we only support 24bit data enable (DE) synchro format */
327 	dvo->config = &rgb_24bit_de_cfg;
328 }
329 
330 static void sti_dvo_bridge_nope(struct drm_bridge *bridge)
331 {
332 	/* do nothing */
333 }
334 
335 static const struct drm_bridge_funcs sti_dvo_bridge_funcs = {
336 	.pre_enable = sti_dvo_pre_enable,
337 	.enable = sti_dvo_bridge_nope,
338 	.disable = sti_dvo_disable,
339 	.post_disable = sti_dvo_bridge_nope,
340 	.mode_set = sti_dvo_set_mode,
341 };
342 
343 static int sti_dvo_connector_get_modes(struct drm_connector *connector)
344 {
345 	struct sti_dvo_connector *dvo_connector
346 		= to_sti_dvo_connector(connector);
347 	struct sti_dvo *dvo = dvo_connector->dvo;
348 
349 	if (dvo->panel)
350 		return dvo->panel->funcs->get_modes(dvo->panel);
351 
352 	return 0;
353 }
354 
355 #define CLK_TOLERANCE_HZ 50
356 
357 static int sti_dvo_connector_mode_valid(struct drm_connector *connector,
358 					struct drm_display_mode *mode)
359 {
360 	int target = mode->clock * 1000;
361 	int target_min = target - CLK_TOLERANCE_HZ;
362 	int target_max = target + CLK_TOLERANCE_HZ;
363 	int result;
364 	struct sti_dvo_connector *dvo_connector
365 		= to_sti_dvo_connector(connector);
366 	struct sti_dvo *dvo = dvo_connector->dvo;
367 
368 	result = clk_round_rate(dvo->clk_pix, target);
369 
370 	DRM_DEBUG_DRIVER("target rate = %d => available rate = %d\n",
371 			 target, result);
372 
373 	if ((result < target_min) || (result > target_max)) {
374 		DRM_DEBUG_DRIVER("dvo pixclk=%d not supported\n", target);
375 		return MODE_BAD;
376 	}
377 
378 	return MODE_OK;
379 }
380 
381 static const
382 struct drm_connector_helper_funcs sti_dvo_connector_helper_funcs = {
383 	.get_modes = sti_dvo_connector_get_modes,
384 	.mode_valid = sti_dvo_connector_mode_valid,
385 };
386 
387 static enum drm_connector_status
388 sti_dvo_connector_detect(struct drm_connector *connector, bool force)
389 {
390 	struct sti_dvo_connector *dvo_connector
391 		= to_sti_dvo_connector(connector);
392 	struct sti_dvo *dvo = dvo_connector->dvo;
393 
394 	DRM_DEBUG_DRIVER("\n");
395 
396 	if (!dvo->panel) {
397 		dvo->panel = of_drm_find_panel(dvo->panel_node);
398 		if (dvo->panel)
399 			drm_panel_attach(dvo->panel, connector);
400 	}
401 
402 	if (dvo->panel)
403 		return connector_status_connected;
404 
405 	return connector_status_disconnected;
406 }
407 
408 static int sti_dvo_late_register(struct drm_connector *connector)
409 {
410 	struct sti_dvo_connector *dvo_connector
411 		= to_sti_dvo_connector(connector);
412 	struct sti_dvo *dvo = dvo_connector->dvo;
413 
414 	if (dvo_debugfs_init(dvo, dvo->drm_dev->primary)) {
415 		DRM_ERROR("DVO debugfs setup failed\n");
416 		return -EINVAL;
417 	}
418 
419 	return 0;
420 }
421 
422 static const struct drm_connector_funcs sti_dvo_connector_funcs = {
423 	.dpms = drm_atomic_helper_connector_dpms,
424 	.fill_modes = drm_helper_probe_single_connector_modes,
425 	.detect = sti_dvo_connector_detect,
426 	.destroy = drm_connector_cleanup,
427 	.reset = drm_atomic_helper_connector_reset,
428 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
429 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
430 	.late_register = sti_dvo_late_register,
431 };
432 
433 static struct drm_encoder *sti_dvo_find_encoder(struct drm_device *dev)
434 {
435 	struct drm_encoder *encoder;
436 
437 	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
438 		if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
439 			return encoder;
440 	}
441 
442 	return NULL;
443 }
444 
445 static int sti_dvo_bind(struct device *dev, struct device *master, void *data)
446 {
447 	struct sti_dvo *dvo = dev_get_drvdata(dev);
448 	struct drm_device *drm_dev = data;
449 	struct drm_encoder *encoder;
450 	struct sti_dvo_connector *connector;
451 	struct drm_connector *drm_connector;
452 	struct drm_bridge *bridge;
453 	int err;
454 
455 	/* Set the drm device handle */
456 	dvo->drm_dev = drm_dev;
457 
458 	encoder = sti_dvo_find_encoder(drm_dev);
459 	if (!encoder)
460 		return -ENOMEM;
461 
462 	connector = devm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
463 	if (!connector)
464 		return -ENOMEM;
465 
466 	connector->dvo = dvo;
467 
468 	bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
469 	if (!bridge)
470 		return -ENOMEM;
471 
472 	bridge->driver_private = dvo;
473 	bridge->funcs = &sti_dvo_bridge_funcs;
474 	bridge->of_node = dvo->dev.of_node;
475 	err = drm_bridge_add(bridge);
476 	if (err) {
477 		DRM_ERROR("Failed to add bridge\n");
478 		return err;
479 	}
480 
481 	err = drm_bridge_attach(drm_dev, bridge);
482 	if (err) {
483 		DRM_ERROR("Failed to attach bridge\n");
484 		return err;
485 	}
486 
487 	dvo->bridge = bridge;
488 	encoder->bridge = bridge;
489 	connector->encoder = encoder;
490 	dvo->encoder = encoder;
491 
492 	drm_connector = (struct drm_connector *)connector;
493 
494 	drm_connector->polled = DRM_CONNECTOR_POLL_HPD;
495 
496 	drm_connector_init(drm_dev, drm_connector,
497 			   &sti_dvo_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
498 	drm_connector_helper_add(drm_connector,
499 				 &sti_dvo_connector_helper_funcs);
500 
501 	err = drm_mode_connector_attach_encoder(drm_connector, encoder);
502 	if (err) {
503 		DRM_ERROR("Failed to attach a connector to a encoder\n");
504 		goto err_sysfs;
505 	}
506 
507 	return 0;
508 
509 err_sysfs:
510 	drm_bridge_remove(bridge);
511 	return -EINVAL;
512 }
513 
514 static void sti_dvo_unbind(struct device *dev,
515 			   struct device *master, void *data)
516 {
517 	struct sti_dvo *dvo = dev_get_drvdata(dev);
518 	struct drm_device *drm_dev = data;
519 
520 	dvo_debugfs_exit(dvo, drm_dev->primary);
521 
522 	drm_bridge_remove(dvo->bridge);
523 }
524 
525 static const struct component_ops sti_dvo_ops = {
526 	.bind = sti_dvo_bind,
527 	.unbind = sti_dvo_unbind,
528 };
529 
530 static int sti_dvo_probe(struct platform_device *pdev)
531 {
532 	struct device *dev = &pdev->dev;
533 	struct sti_dvo *dvo;
534 	struct resource *res;
535 	struct device_node *np = dev->of_node;
536 
537 	DRM_INFO("%s\n", __func__);
538 
539 	dvo = devm_kzalloc(dev, sizeof(*dvo), GFP_KERNEL);
540 	if (!dvo) {
541 		DRM_ERROR("Failed to allocate memory for DVO\n");
542 		return -ENOMEM;
543 	}
544 
545 	dvo->dev = pdev->dev;
546 
547 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dvo-reg");
548 	if (!res) {
549 		DRM_ERROR("Invalid dvo resource\n");
550 		return -ENOMEM;
551 	}
552 	dvo->regs = devm_ioremap_nocache(dev, res->start,
553 			resource_size(res));
554 	if (!dvo->regs)
555 		return -ENOMEM;
556 
557 	dvo->clk_pix = devm_clk_get(dev, "dvo_pix");
558 	if (IS_ERR(dvo->clk_pix)) {
559 		DRM_ERROR("Cannot get dvo_pix clock\n");
560 		return PTR_ERR(dvo->clk_pix);
561 	}
562 
563 	dvo->clk = devm_clk_get(dev, "dvo");
564 	if (IS_ERR(dvo->clk)) {
565 		DRM_ERROR("Cannot get dvo clock\n");
566 		return PTR_ERR(dvo->clk);
567 	}
568 
569 	dvo->clk_main_parent = devm_clk_get(dev, "main_parent");
570 	if (IS_ERR(dvo->clk_main_parent)) {
571 		DRM_DEBUG_DRIVER("Cannot get main_parent clock\n");
572 		dvo->clk_main_parent = NULL;
573 	}
574 
575 	dvo->clk_aux_parent = devm_clk_get(dev, "aux_parent");
576 	if (IS_ERR(dvo->clk_aux_parent)) {
577 		DRM_DEBUG_DRIVER("Cannot get aux_parent clock\n");
578 		dvo->clk_aux_parent = NULL;
579 	}
580 
581 	dvo->panel_node = of_parse_phandle(np, "sti,panel", 0);
582 	if (!dvo->panel_node)
583 		DRM_ERROR("No panel associated to the dvo output\n");
584 	of_node_put(dvo->panel_node);
585 
586 	platform_set_drvdata(pdev, dvo);
587 
588 	return component_add(&pdev->dev, &sti_dvo_ops);
589 }
590 
591 static int sti_dvo_remove(struct platform_device *pdev)
592 {
593 	component_del(&pdev->dev, &sti_dvo_ops);
594 	return 0;
595 }
596 
597 static struct of_device_id dvo_of_match[] = {
598 	{ .compatible = "st,stih407-dvo", },
599 	{ /* end node */ }
600 };
601 MODULE_DEVICE_TABLE(of, dvo_of_match);
602 
603 struct platform_driver sti_dvo_driver = {
604 	.driver = {
605 		.name = "sti-dvo",
606 		.owner = THIS_MODULE,
607 		.of_match_table = dvo_of_match,
608 	},
609 	.probe = sti_dvo_probe,
610 	.remove = sti_dvo_remove,
611 };
612 
613 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
614 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
615 MODULE_LICENSE("GPL");
616