Linux Audio

Check our new training course

Loading...
Note: File does not exist in v4.6.
  1/*
  2 * (C) COPYRIGHT 2012-2013 ARM Limited. All rights reserved.
  3 *
  4 * Parts of this file were based on sources as follows:
  5 *
  6 * Copyright (c) 2006-2008 Intel Corporation
  7 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
  8 * Copyright (C) 2011 Texas Instruments
  9 *
 10 * This program is free software and is provided to you under the terms of the
 11 * GNU General Public License version 2 as published by the Free Software
 12 * Foundation, and any use by you of this program is subject to the terms of
 13 * such GNU licence.
 14 *
 15 */
 16
 17#include <linux/amba/clcd-regs.h>
 18#include <linux/clk.h>
 19#include <linux/version.h>
 20#include <linux/dma-buf.h>
 21#include <linux/of_graph.h>
 22
 23#include <drm/drmP.h>
 24#include <drm/drm_gem_cma_helper.h>
 25#include <drm/drm_gem_framebuffer_helper.h>
 26#include <drm/drm_fb_cma_helper.h>
 27
 28#include "pl111_drm.h"
 29
 30irqreturn_t pl111_irq(int irq, void *data)
 31{
 32	struct pl111_drm_dev_private *priv = data;
 33	u32 irq_stat;
 34	irqreturn_t status = IRQ_NONE;
 35
 36	irq_stat = readl(priv->regs + CLCD_PL111_MIS);
 37
 38	if (!irq_stat)
 39		return IRQ_NONE;
 40
 41	if (irq_stat & CLCD_IRQ_NEXTBASE_UPDATE) {
 42		drm_crtc_handle_vblank(&priv->pipe.crtc);
 43
 44		status = IRQ_HANDLED;
 45	}
 46
 47	/* Clear the interrupt once done */
 48	writel(irq_stat, priv->regs + CLCD_PL111_ICR);
 49
 50	return status;
 51}
 52
 53static enum drm_mode_status
 54pl111_mode_valid(struct drm_crtc *crtc,
 55		 const struct drm_display_mode *mode)
 56{
 57	struct drm_device *drm = crtc->dev;
 58	struct pl111_drm_dev_private *priv = drm->dev_private;
 59	u32 cpp = priv->variant->fb_bpp / 8;
 60	u64 bw;
 61
 62	/*
 63	 * We use the pixelclock to also account for interlaced modes, the
 64	 * resulting bandwidth is in bytes per second.
 65	 */
 66	bw = mode->clock * 1000; /* In Hz */
 67	bw = bw * mode->hdisplay * mode->vdisplay * cpp;
 68	bw = div_u64(bw, mode->htotal * mode->vtotal);
 69
 70	/*
 71	 * If no bandwidth constraints, anything goes, else
 72	 * check if we are too fast.
 73	 */
 74	if (priv->memory_bw && (bw > priv->memory_bw)) {
 75		DRM_DEBUG_KMS("%d x %d @ %d Hz, %d cpp, bw %llu too fast\n",
 76			      mode->hdisplay, mode->vdisplay,
 77			      mode->clock * 1000, cpp, bw);
 78
 79		return MODE_BAD;
 80	}
 81	DRM_DEBUG_KMS("%d x %d @ %d Hz, %d cpp, bw %llu bytes/s OK\n",
 82		      mode->hdisplay, mode->vdisplay,
 83		      mode->clock * 1000, cpp, bw);
 84
 85	return MODE_OK;
 86}
 87
 88static int pl111_display_check(struct drm_simple_display_pipe *pipe,
 89			       struct drm_plane_state *pstate,
 90			       struct drm_crtc_state *cstate)
 91{
 92	const struct drm_display_mode *mode = &cstate->mode;
 93	struct drm_framebuffer *old_fb = pipe->plane.state->fb;
 94	struct drm_framebuffer *fb = pstate->fb;
 95
 96	if (mode->hdisplay % 16)
 97		return -EINVAL;
 98
 99	if (fb) {
100		u32 offset = drm_fb_cma_get_gem_addr(fb, pstate, 0);
101
102		/* FB base address must be dword aligned. */
103		if (offset & 3)
104			return -EINVAL;
105
106		/* There's no pitch register -- the mode's hdisplay
107		 * controls it.
108		 */
109		if (fb->pitches[0] != mode->hdisplay * fb->format->cpp[0])
110			return -EINVAL;
111
112		/* We can't change the FB format in a flicker-free
113		 * manner (and only update it during CRTC enable).
114		 */
115		if (old_fb && old_fb->format != fb->format)
116			cstate->mode_changed = true;
117	}
118
119	return 0;
120}
121
122static void pl111_display_enable(struct drm_simple_display_pipe *pipe,
123				 struct drm_crtc_state *cstate)
124{
125	struct drm_crtc *crtc = &pipe->crtc;
126	struct drm_plane *plane = &pipe->plane;
127	struct drm_device *drm = crtc->dev;
128	struct pl111_drm_dev_private *priv = drm->dev_private;
129	const struct drm_display_mode *mode = &cstate->mode;
130	struct drm_framebuffer *fb = plane->state->fb;
131	struct drm_connector *connector = priv->connector;
132	struct drm_bridge *bridge = priv->bridge;
133	u32 cntl;
134	u32 ppl, hsw, hfp, hbp;
135	u32 lpp, vsw, vfp, vbp;
136	u32 cpl, tim2;
137	int ret;
138
139	ret = clk_set_rate(priv->clk, mode->clock * 1000);
140	if (ret) {
141		dev_err(drm->dev,
142			"Failed to set pixel clock rate to %d: %d\n",
143			mode->clock * 1000, ret);
144	}
145
146	clk_prepare_enable(priv->clk);
147
148	ppl = (mode->hdisplay / 16) - 1;
149	hsw = mode->hsync_end - mode->hsync_start - 1;
150	hfp = mode->hsync_start - mode->hdisplay - 1;
151	hbp = mode->htotal - mode->hsync_end - 1;
152
153	lpp = mode->vdisplay - 1;
154	vsw = mode->vsync_end - mode->vsync_start - 1;
155	vfp = mode->vsync_start - mode->vdisplay;
156	vbp = mode->vtotal - mode->vsync_end;
157
158	cpl = mode->hdisplay - 1;
159
160	writel((ppl << 2) |
161	       (hsw << 8) |
162	       (hfp << 16) |
163	       (hbp << 24),
164	       priv->regs + CLCD_TIM0);
165	writel(lpp |
166	       (vsw << 10) |
167	       (vfp << 16) |
168	       (vbp << 24),
169	       priv->regs + CLCD_TIM1);
170
171	spin_lock(&priv->tim2_lock);
172
173	tim2 = readl(priv->regs + CLCD_TIM2);
174	tim2 &= (TIM2_BCD | TIM2_PCD_LO_MASK | TIM2_PCD_HI_MASK);
175
176	if (priv->variant->broken_clockdivider)
177		tim2 |= TIM2_BCD;
178
179	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
180		tim2 |= TIM2_IHS;
181
182	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
183		tim2 |= TIM2_IVS;
184
185	if (connector) {
186		if (connector->display_info.bus_flags & DRM_BUS_FLAG_DE_LOW)
187			tim2 |= TIM2_IOE;
188
189		if (connector->display_info.bus_flags &
190		    DRM_BUS_FLAG_PIXDATA_NEGEDGE)
191			tim2 |= TIM2_IPC;
192	}
193
194	if (bridge) {
195		const struct drm_bridge_timings *btimings = bridge->timings;
196
197		/*
198		 * Here is when things get really fun. Sometimes the bridge
199		 * timings are such that the signal out from PL11x is not
200		 * stable before the receiving bridge (such as a dumb VGA DAC
201		 * or similar) samples it. If that happens, we compensate by
202		 * the only method we have: output the data on the opposite
203		 * edge of the clock so it is for sure stable when it gets
204		 * sampled.
205		 *
206		 * The PL111 manual does not contain proper timining diagrams
207		 * or data for these details, but we know from experiments
208		 * that the setup time is more than 3000 picoseconds (3 ns).
209		 * If we have a bridge that requires the signal to be stable
210		 * earlier than 3000 ps before the clock pulse, we have to
211		 * output the data on the opposite edge to avoid flicker.
212		 */
213		if (btimings && btimings->setup_time_ps >= 3000)
214			tim2 ^= TIM2_IPC;
215	}
216
217	tim2 |= cpl << 16;
218	writel(tim2, priv->regs + CLCD_TIM2);
219	spin_unlock(&priv->tim2_lock);
220
221	writel(0, priv->regs + CLCD_TIM3);
222
223	/* Hard-code TFT panel */
224	cntl = CNTL_LCDEN | CNTL_LCDTFT | CNTL_LCDVCOMP(1);
225
226	/* Note that the the hardware's format reader takes 'r' from
227	 * the low bit, while DRM formats list channels from high bit
228	 * to low bit as you read left to right.
229	 */
230	switch (fb->format->format) {
231	case DRM_FORMAT_ABGR8888:
232	case DRM_FORMAT_XBGR8888:
233		cntl |= CNTL_LCDBPP24;
234		break;
235	case DRM_FORMAT_ARGB8888:
236	case DRM_FORMAT_XRGB8888:
237		cntl |= CNTL_LCDBPP24 | CNTL_BGR;
238		break;
239	case DRM_FORMAT_BGR565:
240		if (priv->variant->is_pl110)
241			cntl |= CNTL_LCDBPP16;
242		else
243			cntl |= CNTL_LCDBPP16_565;
244		break;
245	case DRM_FORMAT_RGB565:
246		if (priv->variant->is_pl110)
247			cntl |= CNTL_LCDBPP16;
248		else
249			cntl |= CNTL_LCDBPP16_565;
250		cntl |= CNTL_BGR;
251		break;
252	case DRM_FORMAT_ABGR1555:
253	case DRM_FORMAT_XBGR1555:
254		cntl |= CNTL_LCDBPP16;
255		break;
256	case DRM_FORMAT_ARGB1555:
257	case DRM_FORMAT_XRGB1555:
258		cntl |= CNTL_LCDBPP16 | CNTL_BGR;
259		break;
260	case DRM_FORMAT_ABGR4444:
261	case DRM_FORMAT_XBGR4444:
262		cntl |= CNTL_LCDBPP16_444;
263		break;
264	case DRM_FORMAT_ARGB4444:
265	case DRM_FORMAT_XRGB4444:
266		cntl |= CNTL_LCDBPP16_444 | CNTL_BGR;
267		break;
268	default:
269		WARN_ONCE(true, "Unknown FB format 0x%08x\n",
270			  fb->format->format);
271		break;
272	}
273
274	/* The PL110 in Integrator/Versatile does the BGR routing externally */
275	if (priv->variant->external_bgr)
276		cntl &= ~CNTL_BGR;
277
278	/* Power sequence: first enable and chill */
279	writel(cntl, priv->regs + priv->ctrl);
280
281	/*
282	 * We expect this delay to stabilize the contrast
283	 * voltage Vee as stipulated by the manual
284	 */
285	msleep(20);
286
287	if (priv->variant_display_enable)
288		priv->variant_display_enable(drm, fb->format->format);
289
290	/* Power Up */
291	cntl |= CNTL_LCDPWR;
292	writel(cntl, priv->regs + priv->ctrl);
293
294	if (!priv->variant->broken_vblank)
295		drm_crtc_vblank_on(crtc);
296}
297
298void pl111_display_disable(struct drm_simple_display_pipe *pipe)
299{
300	struct drm_crtc *crtc = &pipe->crtc;
301	struct drm_device *drm = crtc->dev;
302	struct pl111_drm_dev_private *priv = drm->dev_private;
303	u32 cntl;
304
305	if (!priv->variant->broken_vblank)
306		drm_crtc_vblank_off(crtc);
307
308	/* Power Down */
309	cntl = readl(priv->regs + priv->ctrl);
310	if (cntl & CNTL_LCDPWR) {
311		cntl &= ~CNTL_LCDPWR;
312		writel(cntl, priv->regs + priv->ctrl);
313	}
314
315	/*
316	 * We expect this delay to stabilize the contrast voltage Vee as
317	 * stipulated by the manual
318	 */
319	msleep(20);
320
321	if (priv->variant_display_disable)
322		priv->variant_display_disable(drm);
323
324	/* Disable */
325	writel(0, priv->regs + priv->ctrl);
326
327	clk_disable_unprepare(priv->clk);
328}
329
330static void pl111_display_update(struct drm_simple_display_pipe *pipe,
331				 struct drm_plane_state *old_pstate)
332{
333	struct drm_crtc *crtc = &pipe->crtc;
334	struct drm_device *drm = crtc->dev;
335	struct pl111_drm_dev_private *priv = drm->dev_private;
336	struct drm_pending_vblank_event *event = crtc->state->event;
337	struct drm_plane *plane = &pipe->plane;
338	struct drm_plane_state *pstate = plane->state;
339	struct drm_framebuffer *fb = pstate->fb;
340
341	if (fb) {
342		u32 addr = drm_fb_cma_get_gem_addr(fb, pstate, 0);
343
344		writel(addr, priv->regs + CLCD_UBAS);
345	}
346
347	if (event) {
348		crtc->state->event = NULL;
349
350		spin_lock_irq(&crtc->dev->event_lock);
351		if (crtc->state->active && drm_crtc_vblank_get(crtc) == 0)
352			drm_crtc_arm_vblank_event(crtc, event);
353		else
354			drm_crtc_send_vblank_event(crtc, event);
355		spin_unlock_irq(&crtc->dev->event_lock);
356	}
357}
358
359static int pl111_display_enable_vblank(struct drm_simple_display_pipe *pipe)
360{
361	struct drm_crtc *crtc = &pipe->crtc;
362	struct drm_device *drm = crtc->dev;
363	struct pl111_drm_dev_private *priv = drm->dev_private;
364
365	writel(CLCD_IRQ_NEXTBASE_UPDATE, priv->regs + priv->ienb);
366
367	return 0;
368}
369
370static void pl111_display_disable_vblank(struct drm_simple_display_pipe *pipe)
371{
372	struct drm_crtc *crtc = &pipe->crtc;
373	struct drm_device *drm = crtc->dev;
374	struct pl111_drm_dev_private *priv = drm->dev_private;
375
376	writel(0, priv->regs + priv->ienb);
377}
378
379static int pl111_display_prepare_fb(struct drm_simple_display_pipe *pipe,
380				    struct drm_plane_state *plane_state)
381{
382	return drm_gem_fb_prepare_fb(&pipe->plane, plane_state);
383}
384
385static struct drm_simple_display_pipe_funcs pl111_display_funcs = {
386	.mode_valid = pl111_mode_valid,
387	.check = pl111_display_check,
388	.enable = pl111_display_enable,
389	.disable = pl111_display_disable,
390	.update = pl111_display_update,
391	.prepare_fb = pl111_display_prepare_fb,
392};
393
394static int pl111_clk_div_choose_div(struct clk_hw *hw, unsigned long rate,
395				    unsigned long *prate, bool set_parent)
396{
397	int best_div = 1, div;
398	struct clk_hw *parent = clk_hw_get_parent(hw);
399	unsigned long best_prate = 0;
400	unsigned long best_diff = ~0ul;
401	int max_div = (1 << (TIM2_PCD_LO_BITS + TIM2_PCD_HI_BITS)) - 1;
402
403	for (div = 1; div < max_div; div++) {
404		unsigned long this_prate, div_rate, diff;
405
406		if (set_parent)
407			this_prate = clk_hw_round_rate(parent, rate * div);
408		else
409			this_prate = *prate;
410		div_rate = DIV_ROUND_UP_ULL(this_prate, div);
411		diff = abs(rate - div_rate);
412
413		if (diff < best_diff) {
414			best_div = div;
415			best_diff = diff;
416			best_prate = this_prate;
417		}
418	}
419
420	*prate = best_prate;
421	return best_div;
422}
423
424static long pl111_clk_div_round_rate(struct clk_hw *hw, unsigned long rate,
425				     unsigned long *prate)
426{
427	int div = pl111_clk_div_choose_div(hw, rate, prate, true);
428
429	return DIV_ROUND_UP_ULL(*prate, div);
430}
431
432static unsigned long pl111_clk_div_recalc_rate(struct clk_hw *hw,
433					       unsigned long prate)
434{
435	struct pl111_drm_dev_private *priv =
436		container_of(hw, struct pl111_drm_dev_private, clk_div);
437	u32 tim2 = readl(priv->regs + CLCD_TIM2);
438	int div;
439
440	if (tim2 & TIM2_BCD)
441		return prate;
442
443	div = tim2 & TIM2_PCD_LO_MASK;
444	div |= (tim2 & TIM2_PCD_HI_MASK) >>
445		(TIM2_PCD_HI_SHIFT - TIM2_PCD_LO_BITS);
446	div += 2;
447
448	return DIV_ROUND_UP_ULL(prate, div);
449}
450
451static int pl111_clk_div_set_rate(struct clk_hw *hw, unsigned long rate,
452				  unsigned long prate)
453{
454	struct pl111_drm_dev_private *priv =
455		container_of(hw, struct pl111_drm_dev_private, clk_div);
456	int div = pl111_clk_div_choose_div(hw, rate, &prate, false);
457	u32 tim2;
458
459	spin_lock(&priv->tim2_lock);
460	tim2 = readl(priv->regs + CLCD_TIM2);
461	tim2 &= ~(TIM2_BCD | TIM2_PCD_LO_MASK | TIM2_PCD_HI_MASK);
462
463	if (div == 1) {
464		tim2 |= TIM2_BCD;
465	} else {
466		div -= 2;
467		tim2 |= div & TIM2_PCD_LO_MASK;
468		tim2 |= (div >> TIM2_PCD_LO_BITS) << TIM2_PCD_HI_SHIFT;
469	}
470
471	writel(tim2, priv->regs + CLCD_TIM2);
472	spin_unlock(&priv->tim2_lock);
473
474	return 0;
475}
476
477static const struct clk_ops pl111_clk_div_ops = {
478	.recalc_rate = pl111_clk_div_recalc_rate,
479	.round_rate = pl111_clk_div_round_rate,
480	.set_rate = pl111_clk_div_set_rate,
481};
482
483static int
484pl111_init_clock_divider(struct drm_device *drm)
485{
486	struct pl111_drm_dev_private *priv = drm->dev_private;
487	struct clk *parent = devm_clk_get(drm->dev, "clcdclk");
488	struct clk_hw *div = &priv->clk_div;
489	const char *parent_name;
490	struct clk_init_data init = {
491		.name = "pl111_div",
492		.ops = &pl111_clk_div_ops,
493		.parent_names = &parent_name,
494		.num_parents = 1,
495		.flags = CLK_SET_RATE_PARENT,
496	};
497	int ret;
498
499	if (IS_ERR(parent)) {
500		dev_err(drm->dev, "CLCD: unable to get clcdclk.\n");
501		return PTR_ERR(parent);
502	}
503	/* If the clock divider is broken, use the parent directly */
504	if (priv->variant->broken_clockdivider) {
505		priv->clk = parent;
506		return 0;
507	}
508	parent_name = __clk_get_name(parent);
509
510	spin_lock_init(&priv->tim2_lock);
511	div->init = &init;
512
513	ret = devm_clk_hw_register(drm->dev, div);
514
515	priv->clk = div->clk;
516	return ret;
517}
518
519int pl111_display_init(struct drm_device *drm)
520{
521	struct pl111_drm_dev_private *priv = drm->dev_private;
522	struct device *dev = drm->dev;
523	struct device_node *endpoint;
524	u32 tft_r0b0g0[3];
525	int ret;
526
527	endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
528	if (!endpoint)
529		return -ENODEV;
530
531	if (of_property_read_u32_array(endpoint,
532				       "arm,pl11x,tft-r0g0b0-pads",
533				       tft_r0b0g0,
534				       ARRAY_SIZE(tft_r0b0g0)) != 0) {
535		dev_err(dev, "arm,pl11x,tft-r0g0b0-pads should be 3 ints\n");
536		of_node_put(endpoint);
537		return -ENOENT;
538	}
539	of_node_put(endpoint);
540
541	ret = pl111_init_clock_divider(drm);
542	if (ret)
543		return ret;
544
545	if (!priv->variant->broken_vblank) {
546		pl111_display_funcs.enable_vblank = pl111_display_enable_vblank;
547		pl111_display_funcs.disable_vblank = pl111_display_disable_vblank;
548	}
549
550	ret = drm_simple_display_pipe_init(drm, &priv->pipe,
551					   &pl111_display_funcs,
552					   priv->variant->formats,
553					   priv->variant->nformats,
554					   NULL,
555					   priv->connector);
556	if (ret)
557		return ret;
558
559	return 0;
560}