1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2021 BayLibre, SAS
4  * Author: Neil Armstrong <narmstrong@baylibre.com>
5  * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/kernel.h>
10 #include <linux/mod_devicetable.h>
11 #include <linux/module.h>
12 #include <linux/of_graph.h>
13 #include <linux/platform_device.h>
14 #include <linux/reset.h>
15 #include <linux/phy/phy.h>
16 #include <linux/bitfield.h>
17 
18 #include <video/mipi_display.h>
19 
20 #include <drm/bridge/dw_mipi_dsi.h>
21 #include <drm/drm_mipi_dsi.h>
22 
23 #include <drm/drm_atomic_helper.h>
24 #include <drm/drm_device.h>
25 #include <drm/drm_probe_helper.h>
26 #include <drm/drm_print.h>
27 
28 #include "meson_drv.h"
29 #include "meson_dw_mipi_dsi.h"
30 #include "meson_registers.h"
31 #include "meson_venc.h"
32 
33 #define DRIVER_NAME "meson-dw-mipi-dsi"
34 #define DRIVER_DESC "Amlogic Meson MIPI-DSI DRM driver"
35 
36 struct meson_dw_mipi_dsi {
37 	struct meson_drm *priv;
38 	struct device *dev;
39 	void __iomem *base;
40 	struct phy *phy;
41 	union phy_configure_opts phy_opts;
42 	struct dw_mipi_dsi *dmd;
43 	struct dw_mipi_dsi_plat_data pdata;
44 	struct mipi_dsi_device *dsi_device;
45 	const struct drm_display_mode *mode;
46 	struct clk *bit_clk;
47 	struct clk *px_clk;
48 	struct reset_control *top_rst;
49 };
50 
51 #define encoder_to_meson_dw_mipi_dsi(x) \
52 	container_of(x, struct meson_dw_mipi_dsi, encoder)
53 
54 static void meson_dw_mipi_dsi_hw_init(struct meson_dw_mipi_dsi *mipi_dsi)
55 {
56 	/* Software reset */
57 	writel_bits_relaxed(MIPI_DSI_TOP_SW_RESET_DWC | MIPI_DSI_TOP_SW_RESET_INTR |
58 			    MIPI_DSI_TOP_SW_RESET_DPI | MIPI_DSI_TOP_SW_RESET_TIMING,
59 			    MIPI_DSI_TOP_SW_RESET_DWC | MIPI_DSI_TOP_SW_RESET_INTR |
60 			    MIPI_DSI_TOP_SW_RESET_DPI | MIPI_DSI_TOP_SW_RESET_TIMING,
61 			    mipi_dsi->base + MIPI_DSI_TOP_SW_RESET);
62 	writel_bits_relaxed(MIPI_DSI_TOP_SW_RESET_DWC | MIPI_DSI_TOP_SW_RESET_INTR |
63 			    MIPI_DSI_TOP_SW_RESET_DPI | MIPI_DSI_TOP_SW_RESET_TIMING,
64 			    0, mipi_dsi->base + MIPI_DSI_TOP_SW_RESET);
65 
66 	/* Enable clocks */
67 	writel_bits_relaxed(MIPI_DSI_TOP_CLK_SYSCLK_EN | MIPI_DSI_TOP_CLK_PIXCLK_EN,
68 			    MIPI_DSI_TOP_CLK_SYSCLK_EN | MIPI_DSI_TOP_CLK_PIXCLK_EN,
69 			    mipi_dsi->base + MIPI_DSI_TOP_CLK_CNTL);
70 
71 	/* Take memory out of power down */
72 	writel_relaxed(0, mipi_dsi->base + MIPI_DSI_TOP_MEM_PD);
73 }
74 
75 static int dw_mipi_dsi_phy_init(void *priv_data)
76 {
77 	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
78 	unsigned int dpi_data_format, venc_data_width;
79 	int ret;
80 
81 	/* Set the bit clock rate to hs_clk_rate */
82 	ret = clk_set_rate(mipi_dsi->bit_clk,
83 			   mipi_dsi->phy_opts.mipi_dphy.hs_clk_rate);
84 	if (ret) {
85 		dev_err(mipi_dsi->dev, "Failed to set DSI Bit clock rate %lu (ret %d)\n",
86 			mipi_dsi->phy_opts.mipi_dphy.hs_clk_rate, ret);
87 		return ret;
88 	}
89 
90 	/* Make sure the rate of the bit clock is not modified by someone else */
91 	ret = clk_rate_exclusive_get(mipi_dsi->bit_clk);
92 	if (ret) {
93 		dev_err(mipi_dsi->dev,
94 			"Failed to set the exclusivity on the bit clock rate (ret %d)\n", ret);
95 		return ret;
96 	}
97 
98 	ret = clk_set_rate(mipi_dsi->px_clk, mipi_dsi->mode->clock * 1000);
99 
100 	if (ret) {
101 		dev_err(mipi_dsi->dev, "Failed to set DSI Pixel clock rate %u (%d)\n",
102 			mipi_dsi->mode->clock * 1000, ret);
103 		return ret;
104 	}
105 
106 	switch (mipi_dsi->dsi_device->format) {
107 	case MIPI_DSI_FMT_RGB888:
108 		dpi_data_format = DPI_COLOR_24BIT;
109 		venc_data_width = VENC_IN_COLOR_24B;
110 		break;
111 	case MIPI_DSI_FMT_RGB666:
112 		dpi_data_format = DPI_COLOR_18BIT_CFG_2;
113 		venc_data_width = VENC_IN_COLOR_18B;
114 		break;
115 	case MIPI_DSI_FMT_RGB666_PACKED:
116 	case MIPI_DSI_FMT_RGB565:
117 		return -EINVAL;
118 	}
119 
120 	/* Configure color format for DPI register */
121 	writel_relaxed(FIELD_PREP(MIPI_DSI_TOP_DPI_COLOR_MODE, dpi_data_format) |
122 		       FIELD_PREP(MIPI_DSI_TOP_IN_COLOR_MODE, venc_data_width) |
123 		       FIELD_PREP(MIPI_DSI_TOP_COMP2_SEL, 2) |
124 		       FIELD_PREP(MIPI_DSI_TOP_COMP1_SEL, 1) |
125 		       FIELD_PREP(MIPI_DSI_TOP_COMP0_SEL, 0),
126 			mipi_dsi->base + MIPI_DSI_TOP_CNTL);
127 
128 	return phy_configure(mipi_dsi->phy, &mipi_dsi->phy_opts);
129 }
130 
131 static void dw_mipi_dsi_phy_power_on(void *priv_data)
132 {
133 	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
134 
135 	if (phy_power_on(mipi_dsi->phy))
136 		dev_warn(mipi_dsi->dev, "Failed to power on PHY\n");
137 }
138 
139 static void dw_mipi_dsi_phy_power_off(void *priv_data)
140 {
141 	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
142 
143 	if (phy_power_off(mipi_dsi->phy))
144 		dev_warn(mipi_dsi->dev, "Failed to power off PHY\n");
145 
146 	/* Remove the exclusivity on the bit clock rate */
147 	clk_rate_exclusive_put(mipi_dsi->bit_clk);
148 }
149 
150 static int
151 dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
152 			  unsigned long mode_flags, u32 lanes, u32 format,
153 			  unsigned int *lane_mbps)
154 {
155 	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
156 	int bpp;
157 
158 	mipi_dsi->mode = mode;
159 
160 	bpp = mipi_dsi_pixel_format_to_bpp(mipi_dsi->dsi_device->format);
161 
162 	phy_mipi_dphy_get_default_config(mode->clock * 1000,
163 					 bpp, mipi_dsi->dsi_device->lanes,
164 					 &mipi_dsi->phy_opts.mipi_dphy);
165 
166 	*lane_mbps = DIV_ROUND_UP(mipi_dsi->phy_opts.mipi_dphy.hs_clk_rate, USEC_PER_SEC);
167 
168 	return 0;
169 }
170 
171 static int
172 dw_mipi_dsi_phy_get_timing(void *priv_data, unsigned int lane_mbps,
173 			   struct dw_mipi_dsi_dphy_timing *timing)
174 {
175 	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
176 
177 	switch (mipi_dsi->mode->hdisplay) {
178 	case 240:
179 	case 768:
180 	case 1920:
181 	case 2560:
182 		timing->clk_lp2hs = 23;
183 		timing->clk_hs2lp = 38;
184 		timing->data_lp2hs = 15;
185 		timing->data_hs2lp = 9;
186 		break;
187 
188 	default:
189 		timing->clk_lp2hs = 37;
190 		timing->clk_hs2lp = 135;
191 		timing->data_lp2hs = 50;
192 		timing->data_hs2lp = 3;
193 	}
194 
195 	return 0;
196 }
197 
198 static int
199 dw_mipi_dsi_get_esc_clk_rate(void *priv_data, unsigned int *esc_clk_rate)
200 {
201 	*esc_clk_rate = 4; /* Mhz */
202 
203 	return 0;
204 }
205 
206 static const struct dw_mipi_dsi_phy_ops meson_dw_mipi_dsi_phy_ops = {
207 	.init = dw_mipi_dsi_phy_init,
208 	.power_on = dw_mipi_dsi_phy_power_on,
209 	.power_off = dw_mipi_dsi_phy_power_off,
210 	.get_lane_mbps = dw_mipi_dsi_get_lane_mbps,
211 	.get_timing = dw_mipi_dsi_phy_get_timing,
212 	.get_esc_clk_rate = dw_mipi_dsi_get_esc_clk_rate,
213 };
214 
215 static int meson_dw_mipi_dsi_host_attach(void *priv_data,
216 					 struct mipi_dsi_device *device)
217 {
218 	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
219 	int ret;
220 
221 	mipi_dsi->dsi_device = device;
222 
223 	switch (device->format) {
224 	case MIPI_DSI_FMT_RGB888:
225 		break;
226 	case MIPI_DSI_FMT_RGB666:
227 		break;
228 	case MIPI_DSI_FMT_RGB666_PACKED:
229 	case MIPI_DSI_FMT_RGB565:
230 		dev_err(mipi_dsi->dev, "invalid pixel format %d\n", device->format);
231 		return -EINVAL;
232 	}
233 
234 	ret = phy_init(mipi_dsi->phy);
235 	if (ret)
236 		return ret;
237 
238 	meson_dw_mipi_dsi_hw_init(mipi_dsi);
239 
240 	return 0;
241 }
242 
243 static int meson_dw_mipi_dsi_host_detach(void *priv_data,
244 					 struct mipi_dsi_device *device)
245 {
246 	struct meson_dw_mipi_dsi *mipi_dsi = priv_data;
247 
248 	if (device == mipi_dsi->dsi_device)
249 		mipi_dsi->dsi_device = NULL;
250 	else
251 		return -EINVAL;
252 
253 	return phy_exit(mipi_dsi->phy);
254 }
255 
256 static const struct dw_mipi_dsi_host_ops meson_dw_mipi_dsi_host_ops = {
257 	.attach = meson_dw_mipi_dsi_host_attach,
258 	.detach = meson_dw_mipi_dsi_host_detach,
259 };
260 
261 static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
262 {
263 	struct meson_dw_mipi_dsi *mipi_dsi;
264 	struct device *dev = &pdev->dev;
265 
266 	mipi_dsi = devm_kzalloc(dev, sizeof(*mipi_dsi), GFP_KERNEL);
267 	if (!mipi_dsi)
268 		return -ENOMEM;
269 
270 	mipi_dsi->base = devm_platform_ioremap_resource(pdev, 0);
271 	if (IS_ERR(mipi_dsi->base))
272 		return PTR_ERR(mipi_dsi->base);
273 
274 	mipi_dsi->phy = devm_phy_get(dev, "dphy");
275 	if (IS_ERR(mipi_dsi->phy))
276 		return dev_err_probe(dev, PTR_ERR(mipi_dsi->phy),
277 				     "failed to get mipi dphy\n");
278 
279 	mipi_dsi->bit_clk = devm_clk_get_enabled(dev, "bit");
280 	if (IS_ERR(mipi_dsi->bit_clk)) {
281 		int ret = PTR_ERR(mipi_dsi->bit_clk);
282 
283 		/* TOFIX GP0 on some platforms fails to lock in early boot, defer probe */
284 		if (ret == -EIO)
285 			ret = -EPROBE_DEFER;
286 
287 		return dev_err_probe(dev, ret, "Unable to get enabled bit_clk\n");
288 	}
289 
290 	mipi_dsi->px_clk = devm_clk_get_enabled(dev, "px");
291 	if (IS_ERR(mipi_dsi->px_clk))
292 		return dev_err_probe(dev, PTR_ERR(mipi_dsi->px_clk),
293 				     "Unable to get enabled px_clk\n");
294 
295 	/*
296 	 * We use a TOP reset signal because the APB reset signal
297 	 * is handled by the TOP control registers.
298 	 */
299 	mipi_dsi->top_rst = devm_reset_control_get_exclusive(dev, "top");
300 	if (IS_ERR(mipi_dsi->top_rst))
301 		return dev_err_probe(dev, PTR_ERR(mipi_dsi->top_rst),
302 				     "Unable to get reset control\n");
303 
304 	reset_control_assert(mipi_dsi->top_rst);
305 	usleep_range(10, 20);
306 	reset_control_deassert(mipi_dsi->top_rst);
307 
308 	/* MIPI DSI Controller */
309 
310 	mipi_dsi->dev = dev;
311 	mipi_dsi->pdata.base = mipi_dsi->base;
312 	mipi_dsi->pdata.max_data_lanes = 4;
313 	mipi_dsi->pdata.phy_ops = &meson_dw_mipi_dsi_phy_ops;
314 	mipi_dsi->pdata.host_ops = &meson_dw_mipi_dsi_host_ops;
315 	mipi_dsi->pdata.priv_data = mipi_dsi;
316 	platform_set_drvdata(pdev, mipi_dsi);
317 
318 	mipi_dsi->dmd = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata);
319 	if (IS_ERR(mipi_dsi->dmd))
320 		return dev_err_probe(dev, PTR_ERR(mipi_dsi->dmd),
321 				     "Failed to probe dw_mipi_dsi\n");
322 
323 	return 0;
324 }
325 
326 static int meson_dw_mipi_dsi_remove(struct platform_device *pdev)
327 {
328 	struct meson_dw_mipi_dsi *mipi_dsi = platform_get_drvdata(pdev);
329 
330 	dw_mipi_dsi_remove(mipi_dsi->dmd);
331 
332 	return 0;
333 }
334 
335 static const struct of_device_id meson_dw_mipi_dsi_of_table[] = {
336 	{ .compatible = "amlogic,meson-g12a-dw-mipi-dsi", },
337 	{ }
338 };
339 MODULE_DEVICE_TABLE(of, meson_dw_mipi_dsi_of_table);
340 
341 static struct platform_driver meson_dw_mipi_dsi_platform_driver = {
342 	.probe		= meson_dw_mipi_dsi_probe,
343 	.remove		= meson_dw_mipi_dsi_remove,
344 	.driver		= {
345 		.name		= DRIVER_NAME,
346 		.of_match_table	= meson_dw_mipi_dsi_of_table,
347 	},
348 };
349 module_platform_driver(meson_dw_mipi_dsi_platform_driver);
350 
351 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
352 MODULE_DESCRIPTION(DRIVER_DESC);
353 MODULE_LICENSE("GPL");
354