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