xref: /linux/drivers/gpu/drm/mediatek/mtk_disp_gamma.c (revision d7b4e3287ca3a7baf66efd9158498e551a9550da)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2021 MediaTek Inc.
4  */
5 
6 #include <linux/bitfield.h>
7 #include <linux/clk.h>
8 #include <linux/component.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/platform_device.h>
12 #include <linux/soc/mediatek/mtk-cmdq.h>
13 
14 #include "mtk_disp_drv.h"
15 #include "mtk_drm_crtc.h"
16 #include "mtk_drm_ddp_comp.h"
17 #include "mtk_drm_drv.h"
18 
19 #define DISP_GAMMA_EN				0x0000
20 #define GAMMA_EN					BIT(0)
21 #define DISP_GAMMA_CFG				0x0020
22 #define GAMMA_RELAY_MODE				BIT(0)
23 #define GAMMA_LUT_EN					BIT(1)
24 #define GAMMA_DITHERING					BIT(2)
25 #define GAMMA_LUT_TYPE					BIT(2)
26 #define DISP_GAMMA_SIZE				0x0030
27 #define DISP_GAMMA_SIZE_HSIZE				GENMASK(28, 16)
28 #define DISP_GAMMA_SIZE_VSIZE				GENMASK(12, 0)
29 #define DISP_GAMMA_BANK				0x0100
30 #define DISP_GAMMA_BANK_BANK				GENMASK(1, 0)
31 #define DISP_GAMMA_BANK_DATA_MODE			BIT(2)
32 #define DISP_GAMMA_LUT				0x0700
33 #define DISP_GAMMA_LUT1				0x0b00
34 
35 /* For 10 bit LUT layout, R/G/B are in the same register */
36 #define DISP_GAMMA_LUT_10BIT_R			GENMASK(29, 20)
37 #define DISP_GAMMA_LUT_10BIT_G			GENMASK(19, 10)
38 #define DISP_GAMMA_LUT_10BIT_B			GENMASK(9, 0)
39 
40 /* For 12 bit LUT layout, R/G are in LUT, B is in LUT1 */
41 #define DISP_GAMMA_LUT_12BIT_R			GENMASK(11, 0)
42 #define DISP_GAMMA_LUT_12BIT_G			GENMASK(23, 12)
43 #define DISP_GAMMA_LUT_12BIT_B			GENMASK(11, 0)
44 
45 struct mtk_disp_gamma_data {
46 	bool has_dither;
47 	bool lut_diff;
48 	u16 lut_bank_size;
49 	u16 lut_size;
50 	u8 lut_bits;
51 };
52 
53 /**
54  * struct mtk_disp_gamma - Display Gamma driver structure
55  * @clk:      clock for DISP_GAMMA block
56  * @regs:     MMIO registers base
57  * @cmdq_reg: CMDQ Client register
58  * @data:     platform data for DISP_GAMMA
59  */
60 struct mtk_disp_gamma {
61 	struct clk *clk;
62 	void __iomem *regs;
63 	struct cmdq_client_reg cmdq_reg;
64 	const struct mtk_disp_gamma_data *data;
65 };
66 
67 int mtk_gamma_clk_enable(struct device *dev)
68 {
69 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
70 
71 	return clk_prepare_enable(gamma->clk);
72 }
73 
74 void mtk_gamma_clk_disable(struct device *dev)
75 {
76 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
77 
78 	clk_disable_unprepare(gamma->clk);
79 }
80 
81 unsigned int mtk_gamma_get_lut_size(struct device *dev)
82 {
83 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
84 
85 	if (gamma && gamma->data)
86 		return gamma->data->lut_size;
87 	return 0;
88 }
89 
90 static bool mtk_gamma_lut_is_descending(struct drm_color_lut *lut, u32 lut_size)
91 {
92 	u64 first, last;
93 	int last_entry = lut_size - 1;
94 
95 	first = lut[0].red + lut[0].green + lut[0].blue;
96 	last = lut[last_entry].red + lut[last_entry].green + lut[last_entry].blue;
97 
98 	return !!(first > last);
99 }
100 
101 /*
102  * SoCs supporting 12-bits LUTs are using a new register layout that does
103  * always support (by HW) both 12-bits and 10-bits LUT but, on those, we
104  * ignore the support for 10-bits in this driver and always use 12-bits.
105  *
106  * Summarizing:
107  * - SoC HW support 9/10-bits LUT only
108  *   - Old register layout
109  *     - 10-bits LUT supported
110  *     - 9-bits LUT not supported
111  * - SoC HW support both 10/12bits LUT
112  *   - New register layout
113  *     - 12-bits LUT supported
114  *     - 10-its LUT not supported
115  */
116 void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
117 {
118 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
119 	void __iomem *lut0_base = gamma->regs + DISP_GAMMA_LUT;
120 	void __iomem *lut1_base = gamma->regs + DISP_GAMMA_LUT1;
121 	u32 cfg_val, data_mode, lbank_val, word[2];
122 	u8 lut_bits = gamma->data->lut_bits;
123 	int cur_bank, num_lut_banks;
124 	struct drm_color_lut *lut;
125 	unsigned int i;
126 
127 	/* If there's no gamma lut there's nothing to do here. */
128 	if (!state->gamma_lut)
129 		return;
130 
131 	num_lut_banks = gamma->data->lut_size / gamma->data->lut_bank_size;
132 	lut = (struct drm_color_lut *)state->gamma_lut->data;
133 
134 	/* Switch to 12 bits data mode if supported */
135 	data_mode = FIELD_PREP(DISP_GAMMA_BANK_DATA_MODE, !!(lut_bits == 12));
136 
137 	for (cur_bank = 0; cur_bank < num_lut_banks; cur_bank++) {
138 
139 		/* Switch gamma bank and set data mode before writing LUT */
140 		if (num_lut_banks > 1) {
141 			lbank_val = FIELD_PREP(DISP_GAMMA_BANK_BANK, cur_bank);
142 			lbank_val |= data_mode;
143 			writel(lbank_val, gamma->regs + DISP_GAMMA_BANK);
144 		}
145 
146 		for (i = 0; i < gamma->data->lut_bank_size; i++) {
147 			int n = cur_bank * gamma->data->lut_bank_size + i;
148 			struct drm_color_lut diff, hwlut;
149 
150 			hwlut.red = drm_color_lut_extract(lut[n].red, lut_bits);
151 			hwlut.green = drm_color_lut_extract(lut[n].green, lut_bits);
152 			hwlut.blue = drm_color_lut_extract(lut[n].blue, lut_bits);
153 
154 			if (!gamma->data->lut_diff || (i % 2 == 0)) {
155 				if (lut_bits == 12) {
156 					word[0] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_R, hwlut.red);
157 					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_12BIT_G, hwlut.green);
158 					word[1] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_B, hwlut.blue);
159 				} else {
160 					word[0] = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
161 					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
162 					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
163 				}
164 			} else {
165 				diff.red = lut[n].red - lut[n - 1].red;
166 				diff.red = drm_color_lut_extract(diff.red, lut_bits);
167 
168 				diff.green = lut[n].green - lut[n - 1].green;
169 				diff.green = drm_color_lut_extract(diff.green, lut_bits);
170 
171 				diff.blue = lut[n].blue - lut[n - 1].blue;
172 				diff.blue = drm_color_lut_extract(diff.blue, lut_bits);
173 
174 				if (lut_bits == 12) {
175 					word[0] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_R, diff.red);
176 					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_12BIT_G, diff.green);
177 					word[1] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_B, diff.blue);
178 				} else {
179 					word[0] = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
180 					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
181 					word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
182 				}
183 			}
184 			writel(word[0], lut0_base + i * 4);
185 			if (lut_bits == 12)
186 				writel(word[1], lut1_base + i * 4);
187 		}
188 	}
189 
190 	cfg_val = readl(gamma->regs + DISP_GAMMA_CFG);
191 
192 	if (!gamma->data->has_dither) {
193 		/* Descending or Rising LUT */
194 		if (mtk_gamma_lut_is_descending(lut, gamma->data->lut_size - 1))
195 			cfg_val |= FIELD_PREP(GAMMA_LUT_TYPE, 1);
196 		else
197 			cfg_val &= ~GAMMA_LUT_TYPE;
198 	}
199 
200 	/* Enable the gamma table */
201 	cfg_val |= FIELD_PREP(GAMMA_LUT_EN, 1);
202 
203 	/* Disable RELAY mode to pass the processed image */
204 	cfg_val &= ~GAMMA_RELAY_MODE;
205 
206 	writel(cfg_val, gamma->regs + DISP_GAMMA_CFG);
207 }
208 
209 void mtk_gamma_config(struct device *dev, unsigned int w,
210 		      unsigned int h, unsigned int vrefresh,
211 		      unsigned int bpc, struct cmdq_pkt *cmdq_pkt)
212 {
213 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
214 	u32 sz;
215 
216 	sz = FIELD_PREP(DISP_GAMMA_SIZE_HSIZE, w);
217 	sz |= FIELD_PREP(DISP_GAMMA_SIZE_VSIZE, h);
218 
219 	mtk_ddp_write(cmdq_pkt, sz, &gamma->cmdq_reg, gamma->regs, DISP_GAMMA_SIZE);
220 	if (gamma->data && gamma->data->has_dither)
221 		mtk_dither_set_common(gamma->regs, &gamma->cmdq_reg, bpc,
222 				      DISP_GAMMA_CFG, GAMMA_DITHERING, cmdq_pkt);
223 }
224 
225 void mtk_gamma_start(struct device *dev)
226 {
227 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
228 
229 	writel(GAMMA_EN, gamma->regs + DISP_GAMMA_EN);
230 }
231 
232 void mtk_gamma_stop(struct device *dev)
233 {
234 	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
235 
236 	writel_relaxed(0x0, gamma->regs + DISP_GAMMA_EN);
237 }
238 
239 static int mtk_disp_gamma_bind(struct device *dev, struct device *master,
240 			       void *data)
241 {
242 	return 0;
243 }
244 
245 static void mtk_disp_gamma_unbind(struct device *dev, struct device *master,
246 				  void *data)
247 {
248 }
249 
250 static const struct component_ops mtk_disp_gamma_component_ops = {
251 	.bind	= mtk_disp_gamma_bind,
252 	.unbind = mtk_disp_gamma_unbind,
253 };
254 
255 static int mtk_disp_gamma_probe(struct platform_device *pdev)
256 {
257 	struct device *dev = &pdev->dev;
258 	struct mtk_disp_gamma *priv;
259 	struct resource *res;
260 	int ret;
261 
262 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
263 	if (!priv)
264 		return -ENOMEM;
265 
266 	priv->clk = devm_clk_get(dev, NULL);
267 	if (IS_ERR(priv->clk)) {
268 		dev_err(dev, "failed to get gamma clk\n");
269 		return PTR_ERR(priv->clk);
270 	}
271 
272 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
273 	priv->regs = devm_ioremap_resource(dev, res);
274 	if (IS_ERR(priv->regs)) {
275 		dev_err(dev, "failed to ioremap gamma\n");
276 		return PTR_ERR(priv->regs);
277 	}
278 
279 #if IS_REACHABLE(CONFIG_MTK_CMDQ)
280 	ret = cmdq_dev_get_client_reg(dev, &priv->cmdq_reg, 0);
281 	if (ret)
282 		dev_dbg(dev, "get mediatek,gce-client-reg fail!\n");
283 #endif
284 
285 	priv->data = of_device_get_match_data(dev);
286 	platform_set_drvdata(pdev, priv);
287 
288 	ret = component_add(dev, &mtk_disp_gamma_component_ops);
289 	if (ret)
290 		dev_err(dev, "Failed to add component: %d\n", ret);
291 
292 	return ret;
293 }
294 
295 static void mtk_disp_gamma_remove(struct platform_device *pdev)
296 {
297 	component_del(&pdev->dev, &mtk_disp_gamma_component_ops);
298 }
299 
300 static const struct mtk_disp_gamma_data mt8173_gamma_driver_data = {
301 	.has_dither = true,
302 	.lut_bank_size = 512,
303 	.lut_bits = 10,
304 	.lut_size = 512,
305 };
306 
307 static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
308 	.lut_bank_size = 512,
309 	.lut_bits = 10,
310 	.lut_diff = true,
311 	.lut_size = 512,
312 };
313 
314 static const struct mtk_disp_gamma_data mt8195_gamma_driver_data = {
315 	.lut_bank_size = 256,
316 	.lut_bits = 12,
317 	.lut_diff = true,
318 	.lut_size = 1024,
319 };
320 
321 static const struct of_device_id mtk_disp_gamma_driver_dt_match[] = {
322 	{ .compatible = "mediatek,mt8173-disp-gamma",
323 	  .data = &mt8173_gamma_driver_data},
324 	{ .compatible = "mediatek,mt8183-disp-gamma",
325 	  .data = &mt8183_gamma_driver_data},
326 	{ .compatible = "mediatek,mt8195-disp-gamma",
327 	  .data = &mt8195_gamma_driver_data},
328 	{},
329 };
330 MODULE_DEVICE_TABLE(of, mtk_disp_gamma_driver_dt_match);
331 
332 struct platform_driver mtk_disp_gamma_driver = {
333 	.probe		= mtk_disp_gamma_probe,
334 	.remove_new	= mtk_disp_gamma_remove,
335 	.driver		= {
336 		.name	= "mediatek-disp-gamma",
337 		.owner	= THIS_MODULE,
338 		.of_match_table = mtk_disp_gamma_driver_dt_match,
339 	},
340 };
341