1 /*
2  * Copyright (c) 2015 MediaTek Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 
14 #include <drm/drmP.h>
15 #include <linux/clk.h>
16 #include <linux/component.h>
17 #include <linux/of_device.h>
18 #include <linux/of_irq.h>
19 #include <linux/platform_device.h>
20 
21 #include "mtk_drm_crtc.h"
22 #include "mtk_drm_ddp_comp.h"
23 
24 #define DISP_REG_RDMA_INT_ENABLE		0x0000
25 #define DISP_REG_RDMA_INT_STATUS		0x0004
26 #define RDMA_TARGET_LINE_INT				BIT(5)
27 #define RDMA_FIFO_UNDERFLOW_INT				BIT(4)
28 #define RDMA_EOF_ABNORMAL_INT				BIT(3)
29 #define RDMA_FRAME_END_INT				BIT(2)
30 #define RDMA_FRAME_START_INT				BIT(1)
31 #define RDMA_REG_UPDATE_INT				BIT(0)
32 #define DISP_REG_RDMA_GLOBAL_CON		0x0010
33 #define RDMA_ENGINE_EN					BIT(0)
34 #define DISP_REG_RDMA_SIZE_CON_0		0x0014
35 #define DISP_REG_RDMA_SIZE_CON_1		0x0018
36 #define DISP_REG_RDMA_TARGET_LINE		0x001c
37 #define DISP_REG_RDMA_FIFO_CON			0x0040
38 #define RDMA_FIFO_UNDERFLOW_EN				BIT(31)
39 #define RDMA_FIFO_PSEUDO_SIZE(bytes)			(((bytes) / 16) << 16)
40 #define RDMA_OUTPUT_VALID_FIFO_THRESHOLD(bytes)		((bytes) / 16)
41 #define RDMA_FIFO_SIZE(rdma)			((rdma)->data->fifo_size)
42 
43 struct mtk_disp_rdma_data {
44 	unsigned int fifo_size;
45 };
46 
47 /**
48  * struct mtk_disp_rdma - DISP_RDMA driver structure
49  * @ddp_comp - structure containing type enum and hardware resources
50  * @crtc - associated crtc to report irq events to
51  */
52 struct mtk_disp_rdma {
53 	struct mtk_ddp_comp		ddp_comp;
54 	struct drm_crtc			*crtc;
55 	const struct mtk_disp_rdma_data	*data;
56 };
57 
58 static inline struct mtk_disp_rdma *comp_to_rdma(struct mtk_ddp_comp *comp)
59 {
60 	return container_of(comp, struct mtk_disp_rdma, ddp_comp);
61 }
62 
63 static irqreturn_t mtk_disp_rdma_irq_handler(int irq, void *dev_id)
64 {
65 	struct mtk_disp_rdma *priv = dev_id;
66 	struct mtk_ddp_comp *rdma = &priv->ddp_comp;
67 
68 	/* Clear frame completion interrupt */
69 	writel(0x0, rdma->regs + DISP_REG_RDMA_INT_STATUS);
70 
71 	if (!priv->crtc)
72 		return IRQ_NONE;
73 
74 	mtk_crtc_ddp_irq(priv->crtc, rdma);
75 
76 	return IRQ_HANDLED;
77 }
78 
79 static void rdma_update_bits(struct mtk_ddp_comp *comp, unsigned int reg,
80 			     unsigned int mask, unsigned int val)
81 {
82 	unsigned int tmp = readl(comp->regs + reg);
83 
84 	tmp = (tmp & ~mask) | (val & mask);
85 	writel(tmp, comp->regs + reg);
86 }
87 
88 static void mtk_rdma_enable_vblank(struct mtk_ddp_comp *comp,
89 				   struct drm_crtc *crtc)
90 {
91 	struct mtk_disp_rdma *rdma = comp_to_rdma(comp);
92 
93 	rdma->crtc = crtc;
94 	rdma_update_bits(comp, DISP_REG_RDMA_INT_ENABLE, RDMA_FRAME_END_INT,
95 			 RDMA_FRAME_END_INT);
96 }
97 
98 static void mtk_rdma_disable_vblank(struct mtk_ddp_comp *comp)
99 {
100 	struct mtk_disp_rdma *rdma = comp_to_rdma(comp);
101 
102 	rdma->crtc = NULL;
103 	rdma_update_bits(comp, DISP_REG_RDMA_INT_ENABLE, RDMA_FRAME_END_INT, 0);
104 }
105 
106 static void mtk_rdma_start(struct mtk_ddp_comp *comp)
107 {
108 	rdma_update_bits(comp, DISP_REG_RDMA_GLOBAL_CON, RDMA_ENGINE_EN,
109 			 RDMA_ENGINE_EN);
110 }
111 
112 static void mtk_rdma_stop(struct mtk_ddp_comp *comp)
113 {
114 	rdma_update_bits(comp, DISP_REG_RDMA_GLOBAL_CON, RDMA_ENGINE_EN, 0);
115 }
116 
117 static void mtk_rdma_config(struct mtk_ddp_comp *comp, unsigned int width,
118 			    unsigned int height, unsigned int vrefresh,
119 			    unsigned int bpc)
120 {
121 	unsigned int threshold;
122 	unsigned int reg;
123 	struct mtk_disp_rdma *rdma = comp_to_rdma(comp);
124 
125 	rdma_update_bits(comp, DISP_REG_RDMA_SIZE_CON_0, 0xfff, width);
126 	rdma_update_bits(comp, DISP_REG_RDMA_SIZE_CON_1, 0xfffff, height);
127 
128 	/*
129 	 * Enable FIFO underflow since DSI and DPI can't be blocked.
130 	 * Keep the FIFO pseudo size reset default of 8 KiB. Set the
131 	 * output threshold to 6 microseconds with 7/6 overhead to
132 	 * account for blanking, and with a pixel depth of 4 bytes:
133 	 */
134 	threshold = width * height * vrefresh * 4 * 7 / 1000000;
135 	reg = RDMA_FIFO_UNDERFLOW_EN |
136 	      RDMA_FIFO_PSEUDO_SIZE(RDMA_FIFO_SIZE(rdma)) |
137 	      RDMA_OUTPUT_VALID_FIFO_THRESHOLD(threshold);
138 	writel(reg, comp->regs + DISP_REG_RDMA_FIFO_CON);
139 }
140 
141 static const struct mtk_ddp_comp_funcs mtk_disp_rdma_funcs = {
142 	.config = mtk_rdma_config,
143 	.start = mtk_rdma_start,
144 	.stop = mtk_rdma_stop,
145 	.enable_vblank = mtk_rdma_enable_vblank,
146 	.disable_vblank = mtk_rdma_disable_vblank,
147 };
148 
149 static int mtk_disp_rdma_bind(struct device *dev, struct device *master,
150 			      void *data)
151 {
152 	struct mtk_disp_rdma *priv = dev_get_drvdata(dev);
153 	struct drm_device *drm_dev = data;
154 	int ret;
155 
156 	ret = mtk_ddp_comp_register(drm_dev, &priv->ddp_comp);
157 	if (ret < 0) {
158 		dev_err(dev, "Failed to register component %pOF: %d\n",
159 			dev->of_node, ret);
160 		return ret;
161 	}
162 
163 	return 0;
164 
165 }
166 
167 static void mtk_disp_rdma_unbind(struct device *dev, struct device *master,
168 				 void *data)
169 {
170 	struct mtk_disp_rdma *priv = dev_get_drvdata(dev);
171 	struct drm_device *drm_dev = data;
172 
173 	mtk_ddp_comp_unregister(drm_dev, &priv->ddp_comp);
174 }
175 
176 static const struct component_ops mtk_disp_rdma_component_ops = {
177 	.bind	= mtk_disp_rdma_bind,
178 	.unbind = mtk_disp_rdma_unbind,
179 };
180 
181 static int mtk_disp_rdma_probe(struct platform_device *pdev)
182 {
183 	struct device *dev = &pdev->dev;
184 	struct mtk_disp_rdma *priv;
185 	int comp_id;
186 	int irq;
187 	int ret;
188 
189 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
190 	if (!priv)
191 		return -ENOMEM;
192 
193 	irq = platform_get_irq(pdev, 0);
194 	if (irq < 0)
195 		return irq;
196 
197 	comp_id = mtk_ddp_comp_get_id(dev->of_node, MTK_DISP_RDMA);
198 	if (comp_id < 0) {
199 		dev_err(dev, "Failed to identify by alias: %d\n", comp_id);
200 		return comp_id;
201 	}
202 
203 	ret = mtk_ddp_comp_init(dev, dev->of_node, &priv->ddp_comp, comp_id,
204 				&mtk_disp_rdma_funcs);
205 	if (ret) {
206 		dev_err(dev, "Failed to initialize component: %d\n", ret);
207 		return ret;
208 	}
209 
210 	/* Disable and clear pending interrupts */
211 	writel(0x0, priv->ddp_comp.regs + DISP_REG_RDMA_INT_ENABLE);
212 	writel(0x0, priv->ddp_comp.regs + DISP_REG_RDMA_INT_STATUS);
213 
214 	ret = devm_request_irq(dev, irq, mtk_disp_rdma_irq_handler,
215 			       IRQF_TRIGGER_NONE, dev_name(dev), priv);
216 	if (ret < 0) {
217 		dev_err(dev, "Failed to request irq %d: %d\n", irq, ret);
218 		return ret;
219 	}
220 
221 	priv->data = of_device_get_match_data(dev);
222 
223 	platform_set_drvdata(pdev, priv);
224 
225 	ret = component_add(dev, &mtk_disp_rdma_component_ops);
226 	if (ret)
227 		dev_err(dev, "Failed to add component: %d\n", ret);
228 
229 	return ret;
230 }
231 
232 static int mtk_disp_rdma_remove(struct platform_device *pdev)
233 {
234 	component_del(&pdev->dev, &mtk_disp_rdma_component_ops);
235 
236 	return 0;
237 }
238 
239 static const struct mtk_disp_rdma_data mt2701_rdma_driver_data = {
240 	.fifo_size = SZ_4K,
241 };
242 
243 static const struct mtk_disp_rdma_data mt8173_rdma_driver_data = {
244 	.fifo_size = SZ_8K,
245 };
246 
247 static const struct of_device_id mtk_disp_rdma_driver_dt_match[] = {
248 	{ .compatible = "mediatek,mt2701-disp-rdma",
249 	  .data = &mt2701_rdma_driver_data},
250 	{ .compatible = "mediatek,mt8173-disp-rdma",
251 	  .data = &mt8173_rdma_driver_data},
252 	{},
253 };
254 MODULE_DEVICE_TABLE(of, mtk_disp_rdma_driver_dt_match);
255 
256 struct platform_driver mtk_disp_rdma_driver = {
257 	.probe		= mtk_disp_rdma_probe,
258 	.remove		= mtk_disp_rdma_remove,
259 	.driver		= {
260 		.name	= "mediatek-disp-rdma",
261 		.owner	= THIS_MODULE,
262 		.of_match_table = mtk_disp_rdma_driver_dt_match,
263 	},
264 };
265