1 /* exynos_drm_fimd.c
2  *
3  * Copyright (C) 2011 Samsung Electronics Co.Ltd
4  * Authors:
5  *	Joonyoung Shim <jy0922.shim@samsung.com>
6  *	Inki Dae <inki.dae@samsung.com>
7  *
8  * This program is free software; you can redistribute  it and/or modify it
9  * under  the terms of  the GNU General  Public License as published by the
10  * Free Software Foundation;  either version 2 of the  License, or (at your
11  * option) any later version.
12  *
13  */
14 #include "drmP.h"
15 
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/clk.h>
20 #include <linux/pm_runtime.h>
21 
22 #include <drm/exynos_drm.h>
23 #include <plat/regs-fb-v4.h>
24 
25 #include "exynos_drm_drv.h"
26 #include "exynos_drm_fbdev.h"
27 #include "exynos_drm_crtc.h"
28 
29 /*
30  * FIMD is stand for Fully Interactive Mobile Display and
31  * as a display controller, it transfers contents drawn on memory
32  * to a LCD Panel through Display Interfaces such as RGB or
33  * CPU Interface.
34  */
35 
36 /* position control register for hardware window 0, 2 ~ 4.*/
37 #define VIDOSD_A(win)		(VIDOSD_BASE + 0x00 + (win) * 16)
38 #define VIDOSD_B(win)		(VIDOSD_BASE + 0x04 + (win) * 16)
39 /* size control register for hardware window 0. */
40 #define VIDOSD_C_SIZE_W0	(VIDOSD_BASE + 0x08)
41 /* alpha control register for hardware window 1 ~ 4. */
42 #define VIDOSD_C(win)		(VIDOSD_BASE + 0x18 + (win) * 16)
43 /* size control register for hardware window 1 ~ 4. */
44 #define VIDOSD_D(win)		(VIDOSD_BASE + 0x0C + (win) * 16)
45 
46 #define VIDWx_BUF_START(win, buf)	(VIDW_BUF_START(buf) + (win) * 8)
47 #define VIDWx_BUF_END(win, buf)		(VIDW_BUF_END(buf) + (win) * 8)
48 #define VIDWx_BUF_SIZE(win, buf)	(VIDW_BUF_SIZE(buf) + (win) * 4)
49 
50 /* color key control register for hardware window 1 ~ 4. */
51 #define WKEYCON0_BASE(x)		((WKEYCON0 + 0x140) + (x * 8))
52 /* color key value register for hardware window 1 ~ 4. */
53 #define WKEYCON1_BASE(x)		((WKEYCON1 + 0x140) + (x * 8))
54 
55 /* FIMD has totally five hardware windows. */
56 #define WINDOWS_NR	5
57 
58 #define get_fimd_context(dev)	platform_get_drvdata(to_platform_device(dev))
59 
60 struct fimd_win_data {
61 	unsigned int		offset_x;
62 	unsigned int		offset_y;
63 	unsigned int		ovl_width;
64 	unsigned int		ovl_height;
65 	unsigned int		fb_width;
66 	unsigned int		fb_height;
67 	unsigned int		bpp;
68 	dma_addr_t		dma_addr;
69 	void __iomem		*vaddr;
70 	unsigned int		buf_offsize;
71 	unsigned int		line_size;	/* bytes */
72 	bool			enabled;
73 };
74 
75 struct fimd_context {
76 	struct exynos_drm_subdrv	subdrv;
77 	int				irq;
78 	struct drm_crtc			*crtc;
79 	struct clk			*bus_clk;
80 	struct clk			*lcd_clk;
81 	struct resource			*regs_res;
82 	void __iomem			*regs;
83 	struct fimd_win_data		win_data[WINDOWS_NR];
84 	unsigned int			clkdiv;
85 	unsigned int			default_win;
86 	unsigned long			irq_flags;
87 	u32				vidcon0;
88 	u32				vidcon1;
89 	bool				suspended;
90 	struct mutex			lock;
91 
92 	struct exynos_drm_panel_info *panel;
93 };
94 
95 static bool fimd_display_is_connected(struct device *dev)
96 {
97 	DRM_DEBUG_KMS("%s\n", __FILE__);
98 
99 	/* TODO. */
100 
101 	return true;
102 }
103 
104 static void *fimd_get_panel(struct device *dev)
105 {
106 	struct fimd_context *ctx = get_fimd_context(dev);
107 
108 	DRM_DEBUG_KMS("%s\n", __FILE__);
109 
110 	return ctx->panel;
111 }
112 
113 static int fimd_check_timing(struct device *dev, void *timing)
114 {
115 	DRM_DEBUG_KMS("%s\n", __FILE__);
116 
117 	/* TODO. */
118 
119 	return 0;
120 }
121 
122 static int fimd_display_power_on(struct device *dev, int mode)
123 {
124 	DRM_DEBUG_KMS("%s\n", __FILE__);
125 
126 	/* TODO */
127 
128 	return 0;
129 }
130 
131 static struct exynos_drm_display_ops fimd_display_ops = {
132 	.type = EXYNOS_DISPLAY_TYPE_LCD,
133 	.is_connected = fimd_display_is_connected,
134 	.get_panel = fimd_get_panel,
135 	.check_timing = fimd_check_timing,
136 	.power_on = fimd_display_power_on,
137 };
138 
139 static void fimd_dpms(struct device *subdrv_dev, int mode)
140 {
141 	struct fimd_context *ctx = get_fimd_context(subdrv_dev);
142 
143 	DRM_DEBUG_KMS("%s, %d\n", __FILE__, mode);
144 
145 	mutex_lock(&ctx->lock);
146 
147 	switch (mode) {
148 	case DRM_MODE_DPMS_ON:
149 		/*
150 		 * enable fimd hardware only if suspended status.
151 		 *
152 		 * P.S. fimd_dpms function would be called at booting time so
153 		 * clk_enable could be called double time.
154 		 */
155 		if (ctx->suspended)
156 			pm_runtime_get_sync(subdrv_dev);
157 		break;
158 	case DRM_MODE_DPMS_STANDBY:
159 	case DRM_MODE_DPMS_SUSPEND:
160 	case DRM_MODE_DPMS_OFF:
161 		if (!ctx->suspended)
162 			pm_runtime_put_sync(subdrv_dev);
163 		break;
164 	default:
165 		DRM_DEBUG_KMS("unspecified mode %d\n", mode);
166 		break;
167 	}
168 
169 	mutex_unlock(&ctx->lock);
170 }
171 
172 static void fimd_apply(struct device *subdrv_dev)
173 {
174 	struct fimd_context *ctx = get_fimd_context(subdrv_dev);
175 	struct exynos_drm_manager *mgr = ctx->subdrv.manager;
176 	struct exynos_drm_manager_ops *mgr_ops = mgr->ops;
177 	struct exynos_drm_overlay_ops *ovl_ops = mgr->overlay_ops;
178 	struct fimd_win_data *win_data;
179 	int i;
180 
181 	DRM_DEBUG_KMS("%s\n", __FILE__);
182 
183 	for (i = 0; i < WINDOWS_NR; i++) {
184 		win_data = &ctx->win_data[i];
185 		if (win_data->enabled && (ovl_ops && ovl_ops->commit))
186 			ovl_ops->commit(subdrv_dev, i);
187 	}
188 
189 	if (mgr_ops && mgr_ops->commit)
190 		mgr_ops->commit(subdrv_dev);
191 }
192 
193 static void fimd_commit(struct device *dev)
194 {
195 	struct fimd_context *ctx = get_fimd_context(dev);
196 	struct exynos_drm_panel_info *panel = ctx->panel;
197 	struct fb_videomode *timing = &panel->timing;
198 	u32 val;
199 
200 	if (ctx->suspended)
201 		return;
202 
203 	DRM_DEBUG_KMS("%s\n", __FILE__);
204 
205 	/* setup polarity values from machine code. */
206 	writel(ctx->vidcon1, ctx->regs + VIDCON1);
207 
208 	/* setup vertical timing values. */
209 	val = VIDTCON0_VBPD(timing->upper_margin - 1) |
210 	       VIDTCON0_VFPD(timing->lower_margin - 1) |
211 	       VIDTCON0_VSPW(timing->vsync_len - 1);
212 	writel(val, ctx->regs + VIDTCON0);
213 
214 	/* setup horizontal timing values.  */
215 	val = VIDTCON1_HBPD(timing->left_margin - 1) |
216 	       VIDTCON1_HFPD(timing->right_margin - 1) |
217 	       VIDTCON1_HSPW(timing->hsync_len - 1);
218 	writel(val, ctx->regs + VIDTCON1);
219 
220 	/* setup horizontal and vertical display size. */
221 	val = VIDTCON2_LINEVAL(timing->yres - 1) |
222 	       VIDTCON2_HOZVAL(timing->xres - 1);
223 	writel(val, ctx->regs + VIDTCON2);
224 
225 	/* setup clock source, clock divider, enable dma. */
226 	val = ctx->vidcon0;
227 	val &= ~(VIDCON0_CLKVAL_F_MASK | VIDCON0_CLKDIR);
228 
229 	if (ctx->clkdiv > 1)
230 		val |= VIDCON0_CLKVAL_F(ctx->clkdiv - 1) | VIDCON0_CLKDIR;
231 	else
232 		val &= ~VIDCON0_CLKDIR;	/* 1:1 clock */
233 
234 	/*
235 	 * fields of register with prefix '_F' would be updated
236 	 * at vsync(same as dma start)
237 	 */
238 	val |= VIDCON0_ENVID | VIDCON0_ENVID_F;
239 	writel(val, ctx->regs + VIDCON0);
240 }
241 
242 static int fimd_enable_vblank(struct device *dev)
243 {
244 	struct fimd_context *ctx = get_fimd_context(dev);
245 	u32 val;
246 
247 	DRM_DEBUG_KMS("%s\n", __FILE__);
248 
249 	if (ctx->suspended)
250 		return -EPERM;
251 
252 	if (!test_and_set_bit(0, &ctx->irq_flags)) {
253 		val = readl(ctx->regs + VIDINTCON0);
254 
255 		val |= VIDINTCON0_INT_ENABLE;
256 		val |= VIDINTCON0_INT_FRAME;
257 
258 		val &= ~VIDINTCON0_FRAMESEL0_MASK;
259 		val |= VIDINTCON0_FRAMESEL0_VSYNC;
260 		val &= ~VIDINTCON0_FRAMESEL1_MASK;
261 		val |= VIDINTCON0_FRAMESEL1_NONE;
262 
263 		writel(val, ctx->regs + VIDINTCON0);
264 	}
265 
266 	return 0;
267 }
268 
269 static void fimd_disable_vblank(struct device *dev)
270 {
271 	struct fimd_context *ctx = get_fimd_context(dev);
272 	u32 val;
273 
274 	DRM_DEBUG_KMS("%s\n", __FILE__);
275 
276 	if (ctx->suspended)
277 		return;
278 
279 	if (test_and_clear_bit(0, &ctx->irq_flags)) {
280 		val = readl(ctx->regs + VIDINTCON0);
281 
282 		val &= ~VIDINTCON0_INT_FRAME;
283 		val &= ~VIDINTCON0_INT_ENABLE;
284 
285 		writel(val, ctx->regs + VIDINTCON0);
286 	}
287 }
288 
289 static struct exynos_drm_manager_ops fimd_manager_ops = {
290 	.dpms = fimd_dpms,
291 	.apply = fimd_apply,
292 	.commit = fimd_commit,
293 	.enable_vblank = fimd_enable_vblank,
294 	.disable_vblank = fimd_disable_vblank,
295 };
296 
297 static void fimd_win_mode_set(struct device *dev,
298 			      struct exynos_drm_overlay *overlay)
299 {
300 	struct fimd_context *ctx = get_fimd_context(dev);
301 	struct fimd_win_data *win_data;
302 	int win;
303 	unsigned long offset;
304 
305 	DRM_DEBUG_KMS("%s\n", __FILE__);
306 
307 	if (!overlay) {
308 		dev_err(dev, "overlay is NULL\n");
309 		return;
310 	}
311 
312 	win = overlay->zpos;
313 	if (win == DEFAULT_ZPOS)
314 		win = ctx->default_win;
315 
316 	if (win < 0 || win > WINDOWS_NR)
317 		return;
318 
319 	offset = overlay->fb_x * (overlay->bpp >> 3);
320 	offset += overlay->fb_y * overlay->pitch;
321 
322 	DRM_DEBUG_KMS("offset = 0x%lx, pitch = %x\n", offset, overlay->pitch);
323 
324 	win_data = &ctx->win_data[win];
325 
326 	win_data->offset_x = overlay->crtc_x;
327 	win_data->offset_y = overlay->crtc_y;
328 	win_data->ovl_width = overlay->crtc_width;
329 	win_data->ovl_height = overlay->crtc_height;
330 	win_data->fb_width = overlay->fb_width;
331 	win_data->fb_height = overlay->fb_height;
332 	win_data->dma_addr = overlay->dma_addr[0] + offset;
333 	win_data->vaddr = overlay->vaddr[0] + offset;
334 	win_data->bpp = overlay->bpp;
335 	win_data->buf_offsize = (overlay->fb_width - overlay->crtc_width) *
336 				(overlay->bpp >> 3);
337 	win_data->line_size = overlay->crtc_width * (overlay->bpp >> 3);
338 
339 	DRM_DEBUG_KMS("offset_x = %d, offset_y = %d\n",
340 			win_data->offset_x, win_data->offset_y);
341 	DRM_DEBUG_KMS("ovl_width = %d, ovl_height = %d\n",
342 			win_data->ovl_width, win_data->ovl_height);
343 	DRM_DEBUG_KMS("paddr = 0x%lx, vaddr = 0x%lx\n",
344 			(unsigned long)win_data->dma_addr,
345 			(unsigned long)win_data->vaddr);
346 	DRM_DEBUG_KMS("fb_width = %d, crtc_width = %d\n",
347 			overlay->fb_width, overlay->crtc_width);
348 }
349 
350 static void fimd_win_set_pixfmt(struct device *dev, unsigned int win)
351 {
352 	struct fimd_context *ctx = get_fimd_context(dev);
353 	struct fimd_win_data *win_data = &ctx->win_data[win];
354 	unsigned long val;
355 
356 	DRM_DEBUG_KMS("%s\n", __FILE__);
357 
358 	val = WINCONx_ENWIN;
359 
360 	switch (win_data->bpp) {
361 	case 1:
362 		val |= WINCON0_BPPMODE_1BPP;
363 		val |= WINCONx_BITSWP;
364 		val |= WINCONx_BURSTLEN_4WORD;
365 		break;
366 	case 2:
367 		val |= WINCON0_BPPMODE_2BPP;
368 		val |= WINCONx_BITSWP;
369 		val |= WINCONx_BURSTLEN_8WORD;
370 		break;
371 	case 4:
372 		val |= WINCON0_BPPMODE_4BPP;
373 		val |= WINCONx_BITSWP;
374 		val |= WINCONx_BURSTLEN_8WORD;
375 		break;
376 	case 8:
377 		val |= WINCON0_BPPMODE_8BPP_PALETTE;
378 		val |= WINCONx_BURSTLEN_8WORD;
379 		val |= WINCONx_BYTSWP;
380 		break;
381 	case 16:
382 		val |= WINCON0_BPPMODE_16BPP_565;
383 		val |= WINCONx_HAWSWP;
384 		val |= WINCONx_BURSTLEN_16WORD;
385 		break;
386 	case 24:
387 		val |= WINCON0_BPPMODE_24BPP_888;
388 		val |= WINCONx_WSWP;
389 		val |= WINCONx_BURSTLEN_16WORD;
390 		break;
391 	case 32:
392 		val |= WINCON1_BPPMODE_28BPP_A4888
393 			| WINCON1_BLD_PIX | WINCON1_ALPHA_SEL;
394 		val |= WINCONx_WSWP;
395 		val |= WINCONx_BURSTLEN_16WORD;
396 		break;
397 	default:
398 		DRM_DEBUG_KMS("invalid pixel size so using unpacked 24bpp.\n");
399 
400 		val |= WINCON0_BPPMODE_24BPP_888;
401 		val |= WINCONx_WSWP;
402 		val |= WINCONx_BURSTLEN_16WORD;
403 		break;
404 	}
405 
406 	DRM_DEBUG_KMS("bpp = %d\n", win_data->bpp);
407 
408 	writel(val, ctx->regs + WINCON(win));
409 }
410 
411 static void fimd_win_set_colkey(struct device *dev, unsigned int win)
412 {
413 	struct fimd_context *ctx = get_fimd_context(dev);
414 	unsigned int keycon0 = 0, keycon1 = 0;
415 
416 	DRM_DEBUG_KMS("%s\n", __FILE__);
417 
418 	keycon0 = ~(WxKEYCON0_KEYBL_EN | WxKEYCON0_KEYEN_F |
419 			WxKEYCON0_DIRCON) | WxKEYCON0_COMPKEY(0);
420 
421 	keycon1 = WxKEYCON1_COLVAL(0xffffffff);
422 
423 	writel(keycon0, ctx->regs + WKEYCON0_BASE(win));
424 	writel(keycon1, ctx->regs + WKEYCON1_BASE(win));
425 }
426 
427 static void fimd_win_commit(struct device *dev, int zpos)
428 {
429 	struct fimd_context *ctx = get_fimd_context(dev);
430 	struct fimd_win_data *win_data;
431 	int win = zpos;
432 	unsigned long val, alpha, size;
433 
434 	DRM_DEBUG_KMS("%s\n", __FILE__);
435 
436 	if (ctx->suspended)
437 		return;
438 
439 	if (win == DEFAULT_ZPOS)
440 		win = ctx->default_win;
441 
442 	if (win < 0 || win > WINDOWS_NR)
443 		return;
444 
445 	win_data = &ctx->win_data[win];
446 
447 	/*
448 	 * SHADOWCON register is used for enabling timing.
449 	 *
450 	 * for example, once only width value of a register is set,
451 	 * if the dma is started then fimd hardware could malfunction so
452 	 * with protect window setting, the register fields with prefix '_F'
453 	 * wouldn't be updated at vsync also but updated once unprotect window
454 	 * is set.
455 	 */
456 
457 	/* protect windows */
458 	val = readl(ctx->regs + SHADOWCON);
459 	val |= SHADOWCON_WINx_PROTECT(win);
460 	writel(val, ctx->regs + SHADOWCON);
461 
462 	/* buffer start address */
463 	val = (unsigned long)win_data->dma_addr;
464 	writel(val, ctx->regs + VIDWx_BUF_START(win, 0));
465 
466 	/* buffer end address */
467 	size = win_data->fb_width * win_data->ovl_height * (win_data->bpp >> 3);
468 	val = (unsigned long)(win_data->dma_addr + size);
469 	writel(val, ctx->regs + VIDWx_BUF_END(win, 0));
470 
471 	DRM_DEBUG_KMS("start addr = 0x%lx, end addr = 0x%lx, size = 0x%lx\n",
472 			(unsigned long)win_data->dma_addr, val, size);
473 	DRM_DEBUG_KMS("ovl_width = %d, ovl_height = %d\n",
474 			win_data->ovl_width, win_data->ovl_height);
475 
476 	/* buffer size */
477 	val = VIDW_BUF_SIZE_OFFSET(win_data->buf_offsize) |
478 		VIDW_BUF_SIZE_PAGEWIDTH(win_data->line_size);
479 	writel(val, ctx->regs + VIDWx_BUF_SIZE(win, 0));
480 
481 	/* OSD position */
482 	val = VIDOSDxA_TOPLEFT_X(win_data->offset_x) |
483 		VIDOSDxA_TOPLEFT_Y(win_data->offset_y);
484 	writel(val, ctx->regs + VIDOSD_A(win));
485 
486 	val = VIDOSDxB_BOTRIGHT_X(win_data->offset_x +
487 					win_data->ovl_width - 1) |
488 		VIDOSDxB_BOTRIGHT_Y(win_data->offset_y +
489 					win_data->ovl_height - 1);
490 	writel(val, ctx->regs + VIDOSD_B(win));
491 
492 	DRM_DEBUG_KMS("osd pos: tx = %d, ty = %d, bx = %d, by = %d\n",
493 			win_data->offset_x, win_data->offset_y,
494 			win_data->offset_x + win_data->ovl_width - 1,
495 			win_data->offset_y + win_data->ovl_height - 1);
496 
497 	/* hardware window 0 doesn't support alpha channel. */
498 	if (win != 0) {
499 		/* OSD alpha */
500 		alpha = VIDISD14C_ALPHA1_R(0xf) |
501 			VIDISD14C_ALPHA1_G(0xf) |
502 			VIDISD14C_ALPHA1_B(0xf);
503 
504 		writel(alpha, ctx->regs + VIDOSD_C(win));
505 	}
506 
507 	/* OSD size */
508 	if (win != 3 && win != 4) {
509 		u32 offset = VIDOSD_D(win);
510 		if (win == 0)
511 			offset = VIDOSD_C_SIZE_W0;
512 		val = win_data->ovl_width * win_data->ovl_height;
513 		writel(val, ctx->regs + offset);
514 
515 		DRM_DEBUG_KMS("osd size = 0x%x\n", (unsigned int)val);
516 	}
517 
518 	fimd_win_set_pixfmt(dev, win);
519 
520 	/* hardware window 0 doesn't support color key. */
521 	if (win != 0)
522 		fimd_win_set_colkey(dev, win);
523 
524 	/* wincon */
525 	val = readl(ctx->regs + WINCON(win));
526 	val |= WINCONx_ENWIN;
527 	writel(val, ctx->regs + WINCON(win));
528 
529 	/* Enable DMA channel and unprotect windows */
530 	val = readl(ctx->regs + SHADOWCON);
531 	val |= SHADOWCON_CHx_ENABLE(win);
532 	val &= ~SHADOWCON_WINx_PROTECT(win);
533 	writel(val, ctx->regs + SHADOWCON);
534 
535 	win_data->enabled = true;
536 }
537 
538 static void fimd_win_disable(struct device *dev, int zpos)
539 {
540 	struct fimd_context *ctx = get_fimd_context(dev);
541 	struct fimd_win_data *win_data;
542 	int win = zpos;
543 	u32 val;
544 
545 	DRM_DEBUG_KMS("%s\n", __FILE__);
546 
547 	if (win == DEFAULT_ZPOS)
548 		win = ctx->default_win;
549 
550 	if (win < 0 || win > WINDOWS_NR)
551 		return;
552 
553 	win_data = &ctx->win_data[win];
554 
555 	/* protect windows */
556 	val = readl(ctx->regs + SHADOWCON);
557 	val |= SHADOWCON_WINx_PROTECT(win);
558 	writel(val, ctx->regs + SHADOWCON);
559 
560 	/* wincon */
561 	val = readl(ctx->regs + WINCON(win));
562 	val &= ~WINCONx_ENWIN;
563 	writel(val, ctx->regs + WINCON(win));
564 
565 	/* unprotect windows */
566 	val = readl(ctx->regs + SHADOWCON);
567 	val &= ~SHADOWCON_CHx_ENABLE(win);
568 	val &= ~SHADOWCON_WINx_PROTECT(win);
569 	writel(val, ctx->regs + SHADOWCON);
570 
571 	win_data->enabled = false;
572 }
573 
574 static struct exynos_drm_overlay_ops fimd_overlay_ops = {
575 	.mode_set = fimd_win_mode_set,
576 	.commit = fimd_win_commit,
577 	.disable = fimd_win_disable,
578 };
579 
580 static struct exynos_drm_manager fimd_manager = {
581 	.pipe		= -1,
582 	.ops		= &fimd_manager_ops,
583 	.overlay_ops	= &fimd_overlay_ops,
584 	.display_ops	= &fimd_display_ops,
585 };
586 
587 static void fimd_finish_pageflip(struct drm_device *drm_dev, int crtc)
588 {
589 	struct exynos_drm_private *dev_priv = drm_dev->dev_private;
590 	struct drm_pending_vblank_event *e, *t;
591 	struct timeval now;
592 	unsigned long flags;
593 	bool is_checked = false;
594 
595 	spin_lock_irqsave(&drm_dev->event_lock, flags);
596 
597 	list_for_each_entry_safe(e, t, &dev_priv->pageflip_event_list,
598 			base.link) {
599 		/* if event's pipe isn't same as crtc then ignore it. */
600 		if (crtc != e->pipe)
601 			continue;
602 
603 		is_checked = true;
604 
605 		do_gettimeofday(&now);
606 		e->event.sequence = 0;
607 		e->event.tv_sec = now.tv_sec;
608 		e->event.tv_usec = now.tv_usec;
609 
610 		list_move_tail(&e->base.link, &e->base.file_priv->event_list);
611 		wake_up_interruptible(&e->base.file_priv->event_wait);
612 	}
613 
614 	if (is_checked) {
615 		/*
616 		 * call drm_vblank_put only in case that drm_vblank_get was
617 		 * called.
618 		 */
619 		if (atomic_read(&drm_dev->vblank_refcount[crtc]) > 0)
620 			drm_vblank_put(drm_dev, crtc);
621 
622 		/*
623 		 * don't off vblank if vblank_disable_allowed is 1,
624 		 * because vblank would be off by timer handler.
625 		 */
626 		if (!drm_dev->vblank_disable_allowed)
627 			drm_vblank_off(drm_dev, crtc);
628 	}
629 
630 	spin_unlock_irqrestore(&drm_dev->event_lock, flags);
631 }
632 
633 static irqreturn_t fimd_irq_handler(int irq, void *dev_id)
634 {
635 	struct fimd_context *ctx = (struct fimd_context *)dev_id;
636 	struct exynos_drm_subdrv *subdrv = &ctx->subdrv;
637 	struct drm_device *drm_dev = subdrv->drm_dev;
638 	struct exynos_drm_manager *manager = subdrv->manager;
639 	u32 val;
640 
641 	val = readl(ctx->regs + VIDINTCON1);
642 
643 	if (val & VIDINTCON1_INT_FRAME)
644 		/* VSYNC interrupt */
645 		writel(VIDINTCON1_INT_FRAME, ctx->regs + VIDINTCON1);
646 
647 	/* check the crtc is detached already from encoder */
648 	if (manager->pipe < 0)
649 		goto out;
650 
651 	drm_handle_vblank(drm_dev, manager->pipe);
652 	fimd_finish_pageflip(drm_dev, manager->pipe);
653 
654 out:
655 	return IRQ_HANDLED;
656 }
657 
658 static int fimd_subdrv_probe(struct drm_device *drm_dev, struct device *dev)
659 {
660 	DRM_DEBUG_KMS("%s\n", __FILE__);
661 
662 	/*
663 	 * enable drm irq mode.
664 	 * - with irq_enabled = 1, we can use the vblank feature.
665 	 *
666 	 * P.S. note that we wouldn't use drm irq handler but
667 	 *	just specific driver own one instead because
668 	 *	drm framework supports only one irq handler.
669 	 */
670 	drm_dev->irq_enabled = 1;
671 
672 	/*
673 	 * with vblank_disable_allowed = 1, vblank interrupt will be disabled
674 	 * by drm timer once a current process gives up ownership of
675 	 * vblank event.(after drm_vblank_put function is called)
676 	 */
677 	drm_dev->vblank_disable_allowed = 1;
678 
679 	return 0;
680 }
681 
682 static void fimd_subdrv_remove(struct drm_device *drm_dev)
683 {
684 	DRM_DEBUG_KMS("%s\n", __FILE__);
685 
686 	/* TODO. */
687 }
688 
689 static int fimd_calc_clkdiv(struct fimd_context *ctx,
690 			    struct fb_videomode *timing)
691 {
692 	unsigned long clk = clk_get_rate(ctx->lcd_clk);
693 	u32 retrace;
694 	u32 clkdiv;
695 	u32 best_framerate = 0;
696 	u32 framerate;
697 
698 	DRM_DEBUG_KMS("%s\n", __FILE__);
699 
700 	retrace = timing->left_margin + timing->hsync_len +
701 				timing->right_margin + timing->xres;
702 	retrace *= timing->upper_margin + timing->vsync_len +
703 				timing->lower_margin + timing->yres;
704 
705 	/* default framerate is 60Hz */
706 	if (!timing->refresh)
707 		timing->refresh = 60;
708 
709 	clk /= retrace;
710 
711 	for (clkdiv = 1; clkdiv < 0x100; clkdiv++) {
712 		int tmp;
713 
714 		/* get best framerate */
715 		framerate = clk / clkdiv;
716 		tmp = timing->refresh - framerate;
717 		if (tmp < 0) {
718 			best_framerate = framerate;
719 			continue;
720 		} else {
721 			if (!best_framerate)
722 				best_framerate = framerate;
723 			else if (tmp < (best_framerate - framerate))
724 				best_framerate = framerate;
725 			break;
726 		}
727 	}
728 
729 	return clkdiv;
730 }
731 
732 static void fimd_clear_win(struct fimd_context *ctx, int win)
733 {
734 	u32 val;
735 
736 	DRM_DEBUG_KMS("%s\n", __FILE__);
737 
738 	writel(0, ctx->regs + WINCON(win));
739 	writel(0, ctx->regs + VIDOSD_A(win));
740 	writel(0, ctx->regs + VIDOSD_B(win));
741 	writel(0, ctx->regs + VIDOSD_C(win));
742 
743 	if (win == 1 || win == 2)
744 		writel(0, ctx->regs + VIDOSD_D(win));
745 
746 	val = readl(ctx->regs + SHADOWCON);
747 	val &= ~SHADOWCON_WINx_PROTECT(win);
748 	writel(val, ctx->regs + SHADOWCON);
749 }
750 
751 static int fimd_power_on(struct fimd_context *ctx, bool enable)
752 {
753 	struct exynos_drm_subdrv *subdrv = &ctx->subdrv;
754 	struct device *dev = subdrv->dev;
755 
756 	DRM_DEBUG_KMS("%s\n", __FILE__);
757 
758 	if (enable != false && enable != true)
759 		return -EINVAL;
760 
761 	if (enable) {
762 		int ret;
763 
764 		ret = clk_enable(ctx->bus_clk);
765 		if (ret < 0)
766 			return ret;
767 
768 		ret = clk_enable(ctx->lcd_clk);
769 		if  (ret < 0) {
770 			clk_disable(ctx->bus_clk);
771 			return ret;
772 		}
773 
774 		ctx->suspended = false;
775 
776 		/* if vblank was enabled status, enable it again. */
777 		if (test_and_clear_bit(0, &ctx->irq_flags))
778 			fimd_enable_vblank(dev);
779 
780 		fimd_apply(dev);
781 	} else {
782 		clk_disable(ctx->lcd_clk);
783 		clk_disable(ctx->bus_clk);
784 
785 		ctx->suspended = true;
786 	}
787 
788 	return 0;
789 }
790 
791 static int __devinit fimd_probe(struct platform_device *pdev)
792 {
793 	struct device *dev = &pdev->dev;
794 	struct fimd_context *ctx;
795 	struct exynos_drm_subdrv *subdrv;
796 	struct exynos_drm_fimd_pdata *pdata;
797 	struct exynos_drm_panel_info *panel;
798 	struct resource *res;
799 	int win;
800 	int ret = -EINVAL;
801 
802 	DRM_DEBUG_KMS("%s\n", __FILE__);
803 
804 	pdata = pdev->dev.platform_data;
805 	if (!pdata) {
806 		dev_err(dev, "no platform data specified\n");
807 		return -EINVAL;
808 	}
809 
810 	panel = &pdata->panel;
811 	if (!panel) {
812 		dev_err(dev, "panel is null.\n");
813 		return -EINVAL;
814 	}
815 
816 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
817 	if (!ctx)
818 		return -ENOMEM;
819 
820 	ctx->bus_clk = clk_get(dev, "fimd");
821 	if (IS_ERR(ctx->bus_clk)) {
822 		dev_err(dev, "failed to get bus clock\n");
823 		ret = PTR_ERR(ctx->bus_clk);
824 		goto err_clk_get;
825 	}
826 
827 	ctx->lcd_clk = clk_get(dev, "sclk_fimd");
828 	if (IS_ERR(ctx->lcd_clk)) {
829 		dev_err(dev, "failed to get lcd clock\n");
830 		ret = PTR_ERR(ctx->lcd_clk);
831 		goto err_bus_clk;
832 	}
833 
834 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
835 	if (!res) {
836 		dev_err(dev, "failed to find registers\n");
837 		ret = -ENOENT;
838 		goto err_clk;
839 	}
840 
841 	ctx->regs_res = request_mem_region(res->start, resource_size(res),
842 					   dev_name(dev));
843 	if (!ctx->regs_res) {
844 		dev_err(dev, "failed to claim register region\n");
845 		ret = -ENOENT;
846 		goto err_clk;
847 	}
848 
849 	ctx->regs = ioremap(res->start, resource_size(res));
850 	if (!ctx->regs) {
851 		dev_err(dev, "failed to map registers\n");
852 		ret = -ENXIO;
853 		goto err_req_region_io;
854 	}
855 
856 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
857 	if (!res) {
858 		dev_err(dev, "irq request failed.\n");
859 		goto err_req_region_irq;
860 	}
861 
862 	ctx->irq = res->start;
863 
864 	ret = request_irq(ctx->irq, fimd_irq_handler, 0, "drm_fimd", ctx);
865 	if (ret < 0) {
866 		dev_err(dev, "irq request failed.\n");
867 		goto err_req_irq;
868 	}
869 
870 	ctx->vidcon0 = pdata->vidcon0;
871 	ctx->vidcon1 = pdata->vidcon1;
872 	ctx->default_win = pdata->default_win;
873 	ctx->panel = panel;
874 
875 	subdrv = &ctx->subdrv;
876 
877 	subdrv->dev = dev;
878 	subdrv->manager = &fimd_manager;
879 	subdrv->probe = fimd_subdrv_probe;
880 	subdrv->remove = fimd_subdrv_remove;
881 
882 	mutex_init(&ctx->lock);
883 
884 	platform_set_drvdata(pdev, ctx);
885 
886 	pm_runtime_enable(dev);
887 	pm_runtime_get_sync(dev);
888 
889 	ctx->clkdiv = fimd_calc_clkdiv(ctx, &panel->timing);
890 	panel->timing.pixclock = clk_get_rate(ctx->lcd_clk) / ctx->clkdiv;
891 
892 	DRM_DEBUG_KMS("pixel clock = %d, clkdiv = %d\n",
893 			panel->timing.pixclock, ctx->clkdiv);
894 
895 	for (win = 0; win < WINDOWS_NR; win++)
896 		fimd_clear_win(ctx, win);
897 
898 	exynos_drm_subdrv_register(subdrv);
899 
900 	return 0;
901 
902 err_req_irq:
903 err_req_region_irq:
904 	iounmap(ctx->regs);
905 
906 err_req_region_io:
907 	release_resource(ctx->regs_res);
908 	kfree(ctx->regs_res);
909 
910 err_clk:
911 	clk_disable(ctx->lcd_clk);
912 	clk_put(ctx->lcd_clk);
913 
914 err_bus_clk:
915 	clk_disable(ctx->bus_clk);
916 	clk_put(ctx->bus_clk);
917 
918 err_clk_get:
919 	kfree(ctx);
920 	return ret;
921 }
922 
923 static int __devexit fimd_remove(struct platform_device *pdev)
924 {
925 	struct device *dev = &pdev->dev;
926 	struct fimd_context *ctx = platform_get_drvdata(pdev);
927 
928 	DRM_DEBUG_KMS("%s\n", __FILE__);
929 
930 	exynos_drm_subdrv_unregister(&ctx->subdrv);
931 
932 	if (ctx->suspended)
933 		goto out;
934 
935 	clk_disable(ctx->lcd_clk);
936 	clk_disable(ctx->bus_clk);
937 
938 	pm_runtime_set_suspended(dev);
939 	pm_runtime_put_sync(dev);
940 
941 out:
942 	pm_runtime_disable(dev);
943 
944 	clk_put(ctx->lcd_clk);
945 	clk_put(ctx->bus_clk);
946 
947 	iounmap(ctx->regs);
948 	release_resource(ctx->regs_res);
949 	kfree(ctx->regs_res);
950 	free_irq(ctx->irq, ctx);
951 
952 	kfree(ctx);
953 
954 	return 0;
955 }
956 
957 #ifdef CONFIG_PM_SLEEP
958 static int fimd_suspend(struct device *dev)
959 {
960 	struct fimd_context *ctx = get_fimd_context(dev);
961 
962 	if (pm_runtime_suspended(dev))
963 		return 0;
964 
965 	/*
966 	 * do not use pm_runtime_suspend(). if pm_runtime_suspend() is
967 	 * called here, an error would be returned by that interface
968 	 * because the usage_count of pm runtime is more than 1.
969 	 */
970 	return fimd_power_on(ctx, false);
971 }
972 
973 static int fimd_resume(struct device *dev)
974 {
975 	struct fimd_context *ctx = get_fimd_context(dev);
976 
977 	/*
978 	 * if entered to sleep when lcd panel was on, the usage_count
979 	 * of pm runtime would still be 1 so in this case, fimd driver
980 	 * should be on directly not drawing on pm runtime interface.
981 	 */
982 	if (!pm_runtime_suspended(dev))
983 		return fimd_power_on(ctx, true);
984 
985 	return 0;
986 }
987 #endif
988 
989 #ifdef CONFIG_PM_RUNTIME
990 static int fimd_runtime_suspend(struct device *dev)
991 {
992 	struct fimd_context *ctx = get_fimd_context(dev);
993 
994 	DRM_DEBUG_KMS("%s\n", __FILE__);
995 
996 	return fimd_power_on(ctx, false);
997 }
998 
999 static int fimd_runtime_resume(struct device *dev)
1000 {
1001 	struct fimd_context *ctx = get_fimd_context(dev);
1002 
1003 	DRM_DEBUG_KMS("%s\n", __FILE__);
1004 
1005 	return fimd_power_on(ctx, true);
1006 }
1007 #endif
1008 
1009 static const struct dev_pm_ops fimd_pm_ops = {
1010 	SET_SYSTEM_SLEEP_PM_OPS(fimd_suspend, fimd_resume)
1011 	SET_RUNTIME_PM_OPS(fimd_runtime_suspend, fimd_runtime_resume, NULL)
1012 };
1013 
1014 struct platform_driver fimd_driver = {
1015 	.probe		= fimd_probe,
1016 	.remove		= __devexit_p(fimd_remove),
1017 	.driver		= {
1018 		.name	= "exynos4-fb",
1019 		.owner	= THIS_MODULE,
1020 		.pm	= &fimd_pm_ops,
1021 	},
1022 };
1023