1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) STMicroelectronics SA 2014
4 * Authors: Benjamin Gaignard <benjamin.gaignard@st.com>
5 * Fabien Dessenne <fabien.dessenne@st.com>
6 * Vincent Abriou <vincent.abriou@st.com>
7 * for STMicroelectronics.
8 */
9
10 #include <linux/module.h>
11 #include <linux/io.h>
12 #include <linux/notifier.h>
13 #include <linux/of_platform.h>
14 #include <linux/platform_device.h>
15
16 #include <drm/drm_modes.h>
17 #include <drm/drm_print.h>
18
19 #include "sti_drv.h"
20 #include "sti_vtg.h"
21
22 #define VTG_MODE_MASTER 0
23
24 /* registers offset */
25 #define VTG_MODE 0x0000
26 #define VTG_CLKLN 0x0008
27 #define VTG_HLFLN 0x000C
28 #define VTG_DRST_AUTOC 0x0010
29 #define VTG_VID_TFO 0x0040
30 #define VTG_VID_TFS 0x0044
31 #define VTG_VID_BFO 0x0048
32 #define VTG_VID_BFS 0x004C
33
34 #define VTG_HOST_ITS 0x0078
35 #define VTG_HOST_ITS_BCLR 0x007C
36 #define VTG_HOST_ITM_BCLR 0x0088
37 #define VTG_HOST_ITM_BSET 0x008C
38
39 #define VTG_H_HD_1 0x00C0
40 #define VTG_TOP_V_VD_1 0x00C4
41 #define VTG_BOT_V_VD_1 0x00C8
42 #define VTG_TOP_V_HD_1 0x00CC
43 #define VTG_BOT_V_HD_1 0x00D0
44
45 #define VTG_H_HD_2 0x00E0
46 #define VTG_TOP_V_VD_2 0x00E4
47 #define VTG_BOT_V_VD_2 0x00E8
48 #define VTG_TOP_V_HD_2 0x00EC
49 #define VTG_BOT_V_HD_2 0x00F0
50
51 #define VTG_H_HD_3 0x0100
52 #define VTG_TOP_V_VD_3 0x0104
53 #define VTG_BOT_V_VD_3 0x0108
54 #define VTG_TOP_V_HD_3 0x010C
55 #define VTG_BOT_V_HD_3 0x0110
56
57 #define VTG_H_HD_4 0x0120
58 #define VTG_TOP_V_VD_4 0x0124
59 #define VTG_BOT_V_VD_4 0x0128
60 #define VTG_TOP_V_HD_4 0x012c
61 #define VTG_BOT_V_HD_4 0x0130
62
63 #define VTG_IRQ_BOTTOM BIT(0)
64 #define VTG_IRQ_TOP BIT(1)
65 #define VTG_IRQ_MASK (VTG_IRQ_TOP | VTG_IRQ_BOTTOM)
66
67 /* Delay introduced by the HDMI in nb of pixel */
68 #define HDMI_DELAY (5)
69
70 /* Delay introduced by the DVO in nb of pixel */
71 #define DVO_DELAY (7)
72
73 /* delay introduced by the Arbitrary Waveform Generator in nb of pixels */
74 #define AWG_DELAY_HD (-9)
75 #define AWG_DELAY_ED (-8)
76 #define AWG_DELAY_SD (-7)
77
78 /*
79 * STI VTG register offset structure
80 *
81 *@h_hd: stores the VTG_H_HD_x register offset
82 *@top_v_vd: stores the VTG_TOP_V_VD_x register offset
83 *@bot_v_vd: stores the VTG_BOT_V_VD_x register offset
84 *@top_v_hd: stores the VTG_TOP_V_HD_x register offset
85 *@bot_v_hd: stores the VTG_BOT_V_HD_x register offset
86 */
87 struct sti_vtg_regs_offs {
88 u32 h_hd;
89 u32 top_v_vd;
90 u32 bot_v_vd;
91 u32 top_v_hd;
92 u32 bot_v_hd;
93 };
94
95 #define VTG_MAX_SYNC_OUTPUT 4
96 static const struct sti_vtg_regs_offs vtg_regs_offs[VTG_MAX_SYNC_OUTPUT] = {
97 { VTG_H_HD_1,
98 VTG_TOP_V_VD_1, VTG_BOT_V_VD_1, VTG_TOP_V_HD_1, VTG_BOT_V_HD_1 },
99 { VTG_H_HD_2,
100 VTG_TOP_V_VD_2, VTG_BOT_V_VD_2, VTG_TOP_V_HD_2, VTG_BOT_V_HD_2 },
101 { VTG_H_HD_3,
102 VTG_TOP_V_VD_3, VTG_BOT_V_VD_3, VTG_TOP_V_HD_3, VTG_BOT_V_HD_3 },
103 { VTG_H_HD_4,
104 VTG_TOP_V_VD_4, VTG_BOT_V_VD_4, VTG_TOP_V_HD_4, VTG_BOT_V_HD_4 }
105 };
106
107 /*
108 * STI VTG synchronisation parameters structure
109 *
110 *@hsync: sample number falling and rising edge
111 *@vsync_line_top: vertical top field line number falling and rising edge
112 *@vsync_line_bot: vertical bottom field line number falling and rising edge
113 *@vsync_off_top: vertical top field sample number rising and falling edge
114 *@vsync_off_bot: vertical bottom field sample number rising and falling edge
115 */
116 struct sti_vtg_sync_params {
117 u32 hsync;
118 u32 vsync_line_top;
119 u32 vsync_line_bot;
120 u32 vsync_off_top;
121 u32 vsync_off_bot;
122 };
123
124 /*
125 * STI VTG structure
126 *
127 * @regs: register mapping
128 * @sync_params: synchronisation parameters used to generate timings
129 * @irq: VTG irq
130 * @irq_status: store the IRQ status value
131 * @notifier_list: notifier callback
132 * @crtc: the CRTC for vblank event
133 */
134 struct sti_vtg {
135 void __iomem *regs;
136 struct sti_vtg_sync_params sync_params[VTG_MAX_SYNC_OUTPUT];
137 int irq;
138 u32 irq_status;
139 struct raw_notifier_head notifier_list;
140 struct drm_crtc *crtc;
141 };
142
of_vtg_find(struct device_node * np)143 struct sti_vtg *of_vtg_find(struct device_node *np)
144 {
145 struct platform_device *pdev;
146
147 pdev = of_find_device_by_node(np);
148 if (!pdev)
149 return NULL;
150
151 return (struct sti_vtg *)platform_get_drvdata(pdev);
152 }
153
vtg_reset(struct sti_vtg * vtg)154 static void vtg_reset(struct sti_vtg *vtg)
155 {
156 writel(1, vtg->regs + VTG_DRST_AUTOC);
157 }
158
vtg_set_output_window(void __iomem * regs,const struct drm_display_mode * mode)159 static void vtg_set_output_window(void __iomem *regs,
160 const struct drm_display_mode *mode)
161 {
162 u32 video_top_field_start;
163 u32 video_top_field_stop;
164 u32 video_bottom_field_start;
165 u32 video_bottom_field_stop;
166 u32 xstart = sti_vtg_get_pixel_number(*mode, 0);
167 u32 ystart = sti_vtg_get_line_number(*mode, 0);
168 u32 xstop = sti_vtg_get_pixel_number(*mode, mode->hdisplay - 1);
169 u32 ystop = sti_vtg_get_line_number(*mode, mode->vdisplay - 1);
170
171 /* Set output window to fit the display mode selected */
172 video_top_field_start = (ystart << 16) | xstart;
173 video_top_field_stop = (ystop << 16) | xstop;
174
175 /* Only progressive supported for now */
176 video_bottom_field_start = video_top_field_start;
177 video_bottom_field_stop = video_top_field_stop;
178
179 writel(video_top_field_start, regs + VTG_VID_TFO);
180 writel(video_top_field_stop, regs + VTG_VID_TFS);
181 writel(video_bottom_field_start, regs + VTG_VID_BFO);
182 writel(video_bottom_field_stop, regs + VTG_VID_BFS);
183 }
184
vtg_set_hsync_vsync_pos(struct sti_vtg_sync_params * sync,int delay,const struct drm_display_mode * mode)185 static void vtg_set_hsync_vsync_pos(struct sti_vtg_sync_params *sync,
186 int delay,
187 const struct drm_display_mode *mode)
188 {
189 long clocksperline, start, stop;
190 u32 risesync_top, fallsync_top;
191 u32 risesync_offs_top, fallsync_offs_top;
192
193 clocksperline = mode->htotal;
194
195 /* Get the hsync position */
196 start = 0;
197 stop = mode->hsync_end - mode->hsync_start;
198
199 start += delay;
200 stop += delay;
201
202 if (start < 0)
203 start += clocksperline;
204 else if (start >= clocksperline)
205 start -= clocksperline;
206
207 if (stop < 0)
208 stop += clocksperline;
209 else if (stop >= clocksperline)
210 stop -= clocksperline;
211
212 sync->hsync = (stop << 16) | start;
213
214 /* Get the vsync position */
215 if (delay >= 0) {
216 risesync_top = 1;
217 fallsync_top = risesync_top;
218 fallsync_top += mode->vsync_end - mode->vsync_start;
219
220 fallsync_offs_top = (u32)delay;
221 risesync_offs_top = (u32)delay;
222 } else {
223 risesync_top = mode->vtotal;
224 fallsync_top = mode->vsync_end - mode->vsync_start;
225
226 fallsync_offs_top = clocksperline + delay;
227 risesync_offs_top = clocksperline + delay;
228 }
229
230 sync->vsync_line_top = (fallsync_top << 16) | risesync_top;
231 sync->vsync_off_top = (fallsync_offs_top << 16) | risesync_offs_top;
232
233 /* Only progressive supported for now */
234 sync->vsync_line_bot = sync->vsync_line_top;
235 sync->vsync_off_bot = sync->vsync_off_top;
236 }
237
vtg_set_mode(struct sti_vtg * vtg,int type,struct sti_vtg_sync_params * sync,const struct drm_display_mode * mode)238 static void vtg_set_mode(struct sti_vtg *vtg,
239 int type,
240 struct sti_vtg_sync_params *sync,
241 const struct drm_display_mode *mode)
242 {
243 unsigned int i;
244
245 /* Set the number of clock cycles per line */
246 writel(mode->htotal, vtg->regs + VTG_CLKLN);
247
248 /* Set Half Line Per Field (only progressive supported for now) */
249 writel(mode->vtotal * 2, vtg->regs + VTG_HLFLN);
250
251 /* Program output window */
252 vtg_set_output_window(vtg->regs, mode);
253
254 /* Set hsync and vsync position for HDMI */
255 vtg_set_hsync_vsync_pos(&sync[VTG_SYNC_ID_HDMI - 1], HDMI_DELAY, mode);
256
257 /* Set hsync and vsync position for HD DCS */
258 vtg_set_hsync_vsync_pos(&sync[VTG_SYNC_ID_HDDCS - 1], 0, mode);
259
260 /* Set hsync and vsync position for HDF */
261 vtg_set_hsync_vsync_pos(&sync[VTG_SYNC_ID_HDF - 1], AWG_DELAY_HD, mode);
262
263 /* Set hsync and vsync position for DVO */
264 vtg_set_hsync_vsync_pos(&sync[VTG_SYNC_ID_DVO - 1], DVO_DELAY, mode);
265
266 /* Progam the syncs outputs */
267 for (i = 0; i < VTG_MAX_SYNC_OUTPUT ; i++) {
268 writel(sync[i].hsync,
269 vtg->regs + vtg_regs_offs[i].h_hd);
270 writel(sync[i].vsync_line_top,
271 vtg->regs + vtg_regs_offs[i].top_v_vd);
272 writel(sync[i].vsync_line_bot,
273 vtg->regs + vtg_regs_offs[i].bot_v_vd);
274 writel(sync[i].vsync_off_top,
275 vtg->regs + vtg_regs_offs[i].top_v_hd);
276 writel(sync[i].vsync_off_bot,
277 vtg->regs + vtg_regs_offs[i].bot_v_hd);
278 }
279
280 /* mode */
281 writel(type, vtg->regs + VTG_MODE);
282 }
283
vtg_enable_irq(struct sti_vtg * vtg)284 static void vtg_enable_irq(struct sti_vtg *vtg)
285 {
286 /* clear interrupt status and mask */
287 writel(0xFFFF, vtg->regs + VTG_HOST_ITS_BCLR);
288 writel(0xFFFF, vtg->regs + VTG_HOST_ITM_BCLR);
289 writel(VTG_IRQ_MASK, vtg->regs + VTG_HOST_ITM_BSET);
290 }
291
sti_vtg_set_config(struct sti_vtg * vtg,const struct drm_display_mode * mode)292 void sti_vtg_set_config(struct sti_vtg *vtg,
293 const struct drm_display_mode *mode)
294 {
295 /* write configuration */
296 vtg_set_mode(vtg, VTG_MODE_MASTER, vtg->sync_params, mode);
297
298 vtg_reset(vtg);
299
300 vtg_enable_irq(vtg);
301 }
302
303 /**
304 * sti_vtg_get_line_number
305 *
306 * @mode: display mode to be used
307 * @y: line
308 *
309 * Return the line number according to the display mode taking
310 * into account the Sync and Back Porch information.
311 * Video frame line numbers start at 1, y starts at 0.
312 * In interlaced modes the start line is the field line number of the odd
313 * field, but y is still defined as a progressive frame.
314 */
sti_vtg_get_line_number(struct drm_display_mode mode,int y)315 u32 sti_vtg_get_line_number(struct drm_display_mode mode, int y)
316 {
317 u32 start_line = mode.vtotal - mode.vsync_start + 1;
318
319 if (mode.flags & DRM_MODE_FLAG_INTERLACE)
320 start_line *= 2;
321
322 return start_line + y;
323 }
324
325 /**
326 * sti_vtg_get_pixel_number
327 *
328 * @mode: display mode to be used
329 * @x: row
330 *
331 * Return the pixel number according to the display mode taking
332 * into account the Sync and Back Porch information.
333 * Pixels are counted from 0.
334 */
sti_vtg_get_pixel_number(struct drm_display_mode mode,int x)335 u32 sti_vtg_get_pixel_number(struct drm_display_mode mode, int x)
336 {
337 return mode.htotal - mode.hsync_start + x;
338 }
339
sti_vtg_register_client(struct sti_vtg * vtg,struct notifier_block * nb,struct drm_crtc * crtc)340 int sti_vtg_register_client(struct sti_vtg *vtg, struct notifier_block *nb,
341 struct drm_crtc *crtc)
342 {
343 vtg->crtc = crtc;
344 return raw_notifier_chain_register(&vtg->notifier_list, nb);
345 }
346
sti_vtg_unregister_client(struct sti_vtg * vtg,struct notifier_block * nb)347 int sti_vtg_unregister_client(struct sti_vtg *vtg, struct notifier_block *nb)
348 {
349 return raw_notifier_chain_unregister(&vtg->notifier_list, nb);
350 }
351
vtg_irq_thread(int irq,void * arg)352 static irqreturn_t vtg_irq_thread(int irq, void *arg)
353 {
354 struct sti_vtg *vtg = arg;
355 u32 event;
356
357 event = (vtg->irq_status & VTG_IRQ_TOP) ?
358 VTG_TOP_FIELD_EVENT : VTG_BOTTOM_FIELD_EVENT;
359
360 raw_notifier_call_chain(&vtg->notifier_list, event, vtg->crtc);
361
362 return IRQ_HANDLED;
363 }
364
vtg_irq(int irq,void * arg)365 static irqreturn_t vtg_irq(int irq, void *arg)
366 {
367 struct sti_vtg *vtg = arg;
368
369 vtg->irq_status = readl(vtg->regs + VTG_HOST_ITS);
370
371 writel(vtg->irq_status, vtg->regs + VTG_HOST_ITS_BCLR);
372
373 /* force sync bus write */
374 readl(vtg->regs + VTG_HOST_ITS);
375
376 return IRQ_WAKE_THREAD;
377 }
378
vtg_probe(struct platform_device * pdev)379 static int vtg_probe(struct platform_device *pdev)
380 {
381 struct device *dev = &pdev->dev;
382 struct sti_vtg *vtg;
383 struct resource *res;
384 int ret;
385
386 vtg = devm_kzalloc(dev, sizeof(*vtg), GFP_KERNEL);
387 if (!vtg)
388 return -ENOMEM;
389
390 /* Get Memory ressources */
391 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
392 if (!res) {
393 DRM_ERROR("Get memory resource failed\n");
394 return -ENOMEM;
395 }
396 vtg->regs = devm_ioremap(dev, res->start, resource_size(res));
397 if (!vtg->regs) {
398 DRM_ERROR("failed to remap I/O memory\n");
399 return -ENOMEM;
400 }
401
402 vtg->irq = platform_get_irq(pdev, 0);
403 if (vtg->irq < 0) {
404 DRM_ERROR("Failed to get VTG interrupt\n");
405 return vtg->irq;
406 }
407
408 RAW_INIT_NOTIFIER_HEAD(&vtg->notifier_list);
409
410 ret = devm_request_threaded_irq(dev, vtg->irq, vtg_irq,
411 vtg_irq_thread, IRQF_ONESHOT,
412 dev_name(dev), vtg);
413 if (ret < 0) {
414 DRM_ERROR("Failed to register VTG interrupt\n");
415 return ret;
416 }
417
418 platform_set_drvdata(pdev, vtg);
419
420 DRM_INFO("%s %s\n", __func__, dev_name(dev));
421
422 return 0;
423 }
424
425 static const struct of_device_id vtg_of_match[] = {
426 { .compatible = "st,vtg", },
427 { /* sentinel */ }
428 };
429 MODULE_DEVICE_TABLE(of, vtg_of_match);
430
431 struct platform_driver sti_vtg_driver = {
432 .driver = {
433 .name = "sti-vtg",
434 .owner = THIS_MODULE,
435 .of_match_table = vtg_of_match,
436 },
437 .probe = vtg_probe,
438 };
439
440 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
441 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
442 MODULE_LICENSE("GPL");
443