1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2021 MediaTek Inc.
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/component.h>
8 #include <linux/of.h>
9 #include <linux/platform_device.h>
10 #include <linux/reset.h>
11 #include <linux/soc/mediatek/mtk-cmdq.h>
12 
13 #include "mtk_drm_ddp_comp.h"
14 #include "mtk_drm_drv.h"
15 #include "mtk_disp_drv.h"
16 
17 #define DISP_REG_MERGE_CTRL		0x000
18 #define MERGE_EN				1
19 #define DISP_REG_MERGE_CFG_0		0x010
20 #define DISP_REG_MERGE_CFG_1		0x014
21 #define DISP_REG_MERGE_CFG_4		0x020
22 #define DISP_REG_MERGE_CFG_10		0x038
23 /* no swap */
24 #define SWAP_MODE				0
25 #define FLD_SWAP_MODE				GENMASK(4, 0)
26 #define DISP_REG_MERGE_CFG_12		0x040
27 #define CFG_10_10_1PI_2PO_BUF_MODE		6
28 #define CFG_10_10_2PI_2PO_BUF_MODE		8
29 #define CFG_11_10_1PI_2PO_MERGE			18
30 #define FLD_CFG_MERGE_MODE			GENMASK(4, 0)
31 #define DISP_REG_MERGE_CFG_24		0x070
32 #define DISP_REG_MERGE_CFG_25		0x074
33 #define DISP_REG_MERGE_CFG_26		0x078
34 #define DISP_REG_MERGE_CFG_27		0x07c
35 #define DISP_REG_MERGE_CFG_36		0x0a0
36 #define ULTRA_EN				BIT(0)
37 #define PREULTRA_EN				BIT(4)
38 #define DISP_REG_MERGE_CFG_37		0x0a4
39 /* 0: Off, 1: SRAM0, 2: SRAM1, 3: SRAM0 + SRAM1 */
40 #define BUFFER_MODE				3
41 #define FLD_BUFFER_MODE				GENMASK(1, 0)
42 /*
43  * For the ultra and preultra settings, 6us ~ 9us is experience value
44  * and the maximum frequency of mmsys clock is 594MHz.
45  */
46 #define DISP_REG_MERGE_CFG_40		0x0b0
47 /* 6 us, 594M pixel/sec */
48 #define ULTRA_TH_LOW				(6 * 594)
49 /* 8 us, 594M pixel/sec */
50 #define ULTRA_TH_HIGH				(8 * 594)
51 #define FLD_ULTRA_TH_LOW			GENMASK(15, 0)
52 #define FLD_ULTRA_TH_HIGH			GENMASK(31, 16)
53 #define DISP_REG_MERGE_CFG_41		0x0b4
54 /* 8 us, 594M pixel/sec */
55 #define PREULTRA_TH_LOW				(8 * 594)
56 /* 9 us, 594M pixel/sec */
57 #define PREULTRA_TH_HIGH			(9 * 594)
58 #define FLD_PREULTRA_TH_LOW			GENMASK(15, 0)
59 #define FLD_PREULTRA_TH_HIGH			GENMASK(31, 16)
60 
61 #define DISP_REG_MERGE_MUTE_0		0xf00
62 
63 struct mtk_disp_merge {
64 	void __iomem			*regs;
65 	struct clk			*clk;
66 	struct clk			*async_clk;
67 	struct cmdq_client_reg		cmdq_reg;
68 	bool				fifo_en;
69 	bool				mute_support;
70 	struct reset_control		*reset_ctl;
71 };
72 
73 void mtk_merge_start(struct device *dev)
74 {
75 	mtk_merge_start_cmdq(dev, NULL);
76 }
77 
78 void mtk_merge_stop(struct device *dev)
79 {
80 	mtk_merge_stop_cmdq(dev, NULL);
81 }
82 
83 void mtk_merge_start_cmdq(struct device *dev, struct cmdq_pkt *cmdq_pkt)
84 {
85 	struct mtk_disp_merge *priv = dev_get_drvdata(dev);
86 
87 	if (priv->mute_support)
88 		mtk_ddp_write(cmdq_pkt, 0x0, &priv->cmdq_reg, priv->regs,
89 			      DISP_REG_MERGE_MUTE_0);
90 
91 	mtk_ddp_write(cmdq_pkt, 1, &priv->cmdq_reg, priv->regs,
92 		      DISP_REG_MERGE_CTRL);
93 }
94 
95 void mtk_merge_stop_cmdq(struct device *dev, struct cmdq_pkt *cmdq_pkt)
96 {
97 	struct mtk_disp_merge *priv = dev_get_drvdata(dev);
98 
99 	if (priv->mute_support)
100 		mtk_ddp_write(cmdq_pkt, 0x1, &priv->cmdq_reg, priv->regs,
101 			      DISP_REG_MERGE_MUTE_0);
102 
103 	mtk_ddp_write(cmdq_pkt, 0, &priv->cmdq_reg, priv->regs,
104 		      DISP_REG_MERGE_CTRL);
105 
106 	if (!cmdq_pkt && priv->async_clk)
107 		reset_control_reset(priv->reset_ctl);
108 }
109 
110 static void mtk_merge_fifo_setting(struct mtk_disp_merge *priv,
111 				   struct cmdq_pkt *cmdq_pkt)
112 {
113 	mtk_ddp_write(cmdq_pkt, ULTRA_EN | PREULTRA_EN,
114 		      &priv->cmdq_reg, priv->regs, DISP_REG_MERGE_CFG_36);
115 
116 	mtk_ddp_write_mask(cmdq_pkt, BUFFER_MODE,
117 			   &priv->cmdq_reg, priv->regs, DISP_REG_MERGE_CFG_37,
118 			   FLD_BUFFER_MODE);
119 
120 	mtk_ddp_write_mask(cmdq_pkt, ULTRA_TH_LOW | ULTRA_TH_HIGH << 16,
121 			   &priv->cmdq_reg, priv->regs, DISP_REG_MERGE_CFG_40,
122 			   FLD_ULTRA_TH_LOW | FLD_ULTRA_TH_HIGH);
123 
124 	mtk_ddp_write_mask(cmdq_pkt, PREULTRA_TH_LOW | PREULTRA_TH_HIGH << 16,
125 			   &priv->cmdq_reg, priv->regs, DISP_REG_MERGE_CFG_41,
126 			   FLD_PREULTRA_TH_LOW | FLD_PREULTRA_TH_HIGH);
127 }
128 
129 void mtk_merge_config(struct device *dev, unsigned int w,
130 		      unsigned int h, unsigned int vrefresh,
131 		      unsigned int bpc, struct cmdq_pkt *cmdq_pkt)
132 {
133 	mtk_merge_advance_config(dev, w, 0, h, vrefresh, bpc, cmdq_pkt);
134 }
135 
136 void mtk_merge_advance_config(struct device *dev, unsigned int l_w, unsigned int r_w,
137 			      unsigned int h, unsigned int vrefresh, unsigned int bpc,
138 			      struct cmdq_pkt *cmdq_pkt)
139 {
140 	struct mtk_disp_merge *priv = dev_get_drvdata(dev);
141 	unsigned int mode = CFG_10_10_1PI_2PO_BUF_MODE;
142 
143 	if (!h || !l_w) {
144 		dev_err(dev, "%s: input width(%d) or height(%d) is invalid\n", __func__, l_w, h);
145 		return;
146 	}
147 
148 	if (priv->fifo_en) {
149 		mtk_merge_fifo_setting(priv, cmdq_pkt);
150 		mode = CFG_10_10_2PI_2PO_BUF_MODE;
151 	}
152 
153 	if (r_w)
154 		mode = CFG_11_10_1PI_2PO_MERGE;
155 
156 	mtk_ddp_write(cmdq_pkt, h << 16 | l_w, &priv->cmdq_reg, priv->regs,
157 		      DISP_REG_MERGE_CFG_0);
158 	mtk_ddp_write(cmdq_pkt, h << 16 | r_w, &priv->cmdq_reg, priv->regs,
159 		      DISP_REG_MERGE_CFG_1);
160 	mtk_ddp_write(cmdq_pkt, h << 16 | (l_w + r_w), &priv->cmdq_reg, priv->regs,
161 		      DISP_REG_MERGE_CFG_4);
162 	/*
163 	 * DISP_REG_MERGE_CFG_24 is merge SRAM0 w/h
164 	 * DISP_REG_MERGE_CFG_25 is merge SRAM1 w/h.
165 	 * If r_w > 0, the merge is in merge mode (input0 and input1 merge together),
166 	 * the input0 goes to SRAM0, and input1 goes to SRAM1.
167 	 * If r_w = 0, the merge is in buffer mode, the input goes through SRAM0 and
168 	 * then to SRAM1. Both SRAM0 and SRAM1 are set to the same size.
169 	 */
170 	mtk_ddp_write(cmdq_pkt, h << 16 | l_w, &priv->cmdq_reg, priv->regs,
171 		      DISP_REG_MERGE_CFG_24);
172 	if (r_w)
173 		mtk_ddp_write(cmdq_pkt, h << 16 | r_w, &priv->cmdq_reg, priv->regs,
174 			      DISP_REG_MERGE_CFG_25);
175 	else
176 		mtk_ddp_write(cmdq_pkt, h << 16 | l_w, &priv->cmdq_reg, priv->regs,
177 			      DISP_REG_MERGE_CFG_25);
178 
179 	/*
180 	 * DISP_REG_MERGE_CFG_26 and DISP_REG_MERGE_CFG_27 is only used in LR merge.
181 	 * Only take effect when the merge is setting to merge mode.
182 	 */
183 	mtk_ddp_write(cmdq_pkt, h << 16 | l_w, &priv->cmdq_reg, priv->regs,
184 		      DISP_REG_MERGE_CFG_26);
185 	mtk_ddp_write(cmdq_pkt, h << 16 | r_w, &priv->cmdq_reg, priv->regs,
186 		      DISP_REG_MERGE_CFG_27);
187 
188 	mtk_ddp_write_mask(cmdq_pkt, SWAP_MODE, &priv->cmdq_reg, priv->regs,
189 			   DISP_REG_MERGE_CFG_10, FLD_SWAP_MODE);
190 	mtk_ddp_write_mask(cmdq_pkt, mode, &priv->cmdq_reg, priv->regs,
191 			   DISP_REG_MERGE_CFG_12, FLD_CFG_MERGE_MODE);
192 }
193 
194 int mtk_merge_clk_enable(struct device *dev)
195 {
196 	int ret = 0;
197 	struct mtk_disp_merge *priv = dev_get_drvdata(dev);
198 
199 	ret = clk_prepare_enable(priv->clk);
200 	if (ret) {
201 		dev_err(dev, "merge clk prepare enable failed\n");
202 		return ret;
203 	}
204 
205 	ret = clk_prepare_enable(priv->async_clk);
206 	if (ret) {
207 		/* should clean up the state of priv->clk */
208 		clk_disable_unprepare(priv->clk);
209 
210 		dev_err(dev, "async clk prepare enable failed\n");
211 		return ret;
212 	}
213 
214 	return ret;
215 }
216 
217 void mtk_merge_clk_disable(struct device *dev)
218 {
219 	struct mtk_disp_merge *priv = dev_get_drvdata(dev);
220 
221 	clk_disable_unprepare(priv->async_clk);
222 	clk_disable_unprepare(priv->clk);
223 }
224 
225 enum drm_mode_status mtk_merge_mode_valid(struct device *dev,
226 					  const struct drm_display_mode *mode)
227 {
228 	struct mtk_disp_merge *priv = dev_get_drvdata(dev);
229 	unsigned long rate;
230 
231 	rate = clk_get_rate(priv->clk);
232 
233 	/* Convert to KHz and round the number */
234 	rate = (rate + 500) / 1000;
235 
236 	if (rate && mode->clock > rate) {
237 		dev_dbg(dev, "invalid clock: %d (>%lu)\n", mode->clock, rate);
238 		return MODE_CLOCK_HIGH;
239 	}
240 
241 	/*
242 	 * Measure the bandwidth requirement of hardware prefetch (per frame)
243 	 *
244 	 * let N = prefetch buffer size in lines
245 	 *         (ex. N=3, then prefetch buffer size = 3 lines)
246 	 *
247 	 * prefetch size = htotal * N (pixels)
248 	 * time per line = 1 / fps / vtotal (seconds)
249 	 * duration      = vbp * time per line
250 	 *               = vbp / fps / vtotal
251 	 *
252 	 * data rate = prefetch size / duration
253 	 *           = htotal * N / (vbp / fps / vtotal)
254 	 *           = htotal * vtotal * fps * N / vbp
255 	 *           = clk * N / vbp (pixels per second)
256 	 *
257 	 * Say 4K60 (CEA-861) is the maximum mode supported by the SoC
258 	 * data rate = 594000K * N / 72 = 8250 (standard)
259 	 * (remove K * N due to the same unit)
260 	 *
261 	 * For 2560x1440@144 (clk=583600K, vbp=17):
262 	 * data rate = 583600 / 17 ~= 34329 > 8250 (NG)
263 	 *
264 	 * For 2560x1440@120 (clk=497760K, vbp=77):
265 	 * data rate = 497760 / 77 ~= 6464 < 8250 (OK)
266 	 *
267 	 * A non-standard 4K60 timing (clk=521280K, vbp=54)
268 	 * data rate = 521280 / 54 ~= 9653 > 8250 (NG)
269 	 *
270 	 * Bandwidth requirement of hardware prefetch increases significantly
271 	 * when the VBP decreases (more than 4x in this example).
272 	 *
273 	 * The proposed formula is only one way to estimate whether our SoC
274 	 * supports the mode setting. The basic idea behind it is just to check
275 	 * if the data rate requirement is too high (directly proportional to
276 	 * pixel clock, inversely proportional to vbp). Please adjust the
277 	 * function if it doesn't fit your situation in the future.
278 	 */
279 	rate = mode->clock / (mode->vtotal - mode->vsync_end);
280 
281 	if (rate > 8250) {
282 		dev_dbg(dev, "invalid rate: %lu (>8250): " DRM_MODE_FMT "\n",
283 			rate, DRM_MODE_ARG(mode));
284 		return MODE_BAD;
285 	}
286 
287 	return MODE_OK;
288 }
289 
290 static int mtk_disp_merge_bind(struct device *dev, struct device *master,
291 			       void *data)
292 {
293 	return 0;
294 }
295 
296 static void mtk_disp_merge_unbind(struct device *dev, struct device *master,
297 				  void *data)
298 {
299 }
300 
301 static const struct component_ops mtk_disp_merge_component_ops = {
302 	.bind	= mtk_disp_merge_bind,
303 	.unbind = mtk_disp_merge_unbind,
304 };
305 
306 static int mtk_disp_merge_probe(struct platform_device *pdev)
307 {
308 	struct device *dev = &pdev->dev;
309 	struct resource *res;
310 	struct mtk_disp_merge *priv;
311 	int ret;
312 
313 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
314 	if (!priv)
315 		return -ENOMEM;
316 
317 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
318 	priv->regs = devm_ioremap_resource(dev, res);
319 	if (IS_ERR(priv->regs)) {
320 		dev_err(dev, "failed to ioremap merge\n");
321 		return PTR_ERR(priv->regs);
322 	}
323 
324 	priv->clk = devm_clk_get(dev, NULL);
325 	if (IS_ERR(priv->clk)) {
326 		dev_err(dev, "failed to get merge clk\n");
327 		return PTR_ERR(priv->clk);
328 	}
329 
330 	priv->async_clk = devm_clk_get_optional(dev, "merge_async");
331 	if (IS_ERR(priv->async_clk)) {
332 		dev_err(dev, "failed to get merge async clock\n");
333 		return PTR_ERR(priv->async_clk);
334 	}
335 
336 	if (priv->async_clk) {
337 		priv->reset_ctl = devm_reset_control_get_optional_exclusive(dev, NULL);
338 		if (IS_ERR(priv->reset_ctl))
339 			return PTR_ERR(priv->reset_ctl);
340 	}
341 
342 #if IS_REACHABLE(CONFIG_MTK_CMDQ)
343 	ret = cmdq_dev_get_client_reg(dev, &priv->cmdq_reg, 0);
344 	if (ret)
345 		dev_dbg(dev, "get mediatek,gce-client-reg fail!\n");
346 #endif
347 
348 	priv->fifo_en = of_property_read_bool(dev->of_node,
349 					      "mediatek,merge-fifo-en");
350 
351 	priv->mute_support = of_property_read_bool(dev->of_node,
352 						   "mediatek,merge-mute");
353 	platform_set_drvdata(pdev, priv);
354 
355 	ret = component_add(dev, &mtk_disp_merge_component_ops);
356 	if (ret != 0)
357 		dev_err(dev, "Failed to add component: %d\n", ret);
358 
359 	return ret;
360 }
361 
362 static void mtk_disp_merge_remove(struct platform_device *pdev)
363 {
364 	component_del(&pdev->dev, &mtk_disp_merge_component_ops);
365 }
366 
367 static const struct of_device_id mtk_disp_merge_driver_dt_match[] = {
368 	{ .compatible = "mediatek,mt8195-disp-merge", },
369 	{},
370 };
371 
372 MODULE_DEVICE_TABLE(of, mtk_disp_merge_driver_dt_match);
373 
374 struct platform_driver mtk_disp_merge_driver = {
375 	.probe = mtk_disp_merge_probe,
376 	.remove_new = mtk_disp_merge_remove,
377 	.driver = {
378 		.name = "mediatek-disp-merge",
379 		.owner = THIS_MODULE,
380 		.of_match_table = mtk_disp_merge_driver_dt_match,
381 	},
382 };
383