xref: /linux/drivers/soc/amlogic/meson-canvas.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2018 BayLibre, SAS
4  * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
5  * Copyright (C) 2014 Endless Mobile
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/mfd/syscon.h>
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/regmap.h>
13 #include <linux/soc/amlogic/meson-canvas.h>
14 #include <linux/of_address.h>
15 #include <linux/of_platform.h>
16 #include <linux/io.h>
17 
18 #define NUM_CANVAS 256
19 
20 /* DMC Registers */
21 #define DMC_CAV_LUT_DATAL	0x00
22 	#define CANVAS_WIDTH_LBIT	29
23 	#define CANVAS_WIDTH_LWID	3
24 #define DMC_CAV_LUT_DATAH	0x04
25 	#define CANVAS_WIDTH_HBIT	0
26 	#define CANVAS_HEIGHT_BIT	9
27 	#define CANVAS_WRAP_BIT		22
28 	#define CANVAS_BLKMODE_BIT	24
29 	#define CANVAS_ENDIAN_BIT	26
30 #define DMC_CAV_LUT_ADDR	0x08
31 	#define CANVAS_LUT_WR_EN	BIT(9)
32 	#define CANVAS_LUT_RD_EN	BIT(8)
33 
34 struct meson_canvas {
35 	struct device *dev;
36 	void __iomem *reg_base;
37 	spinlock_t lock; /* canvas device lock */
38 	u8 used[NUM_CANVAS];
39 	bool supports_endianness;
40 };
41 
42 static void canvas_write(struct meson_canvas *canvas, u32 reg, u32 val)
43 {
44 	writel_relaxed(val, canvas->reg_base + reg);
45 }
46 
47 static u32 canvas_read(struct meson_canvas *canvas, u32 reg)
48 {
49 	return readl_relaxed(canvas->reg_base + reg);
50 }
51 
52 struct meson_canvas *meson_canvas_get(struct device *dev)
53 {
54 	struct device_node *canvas_node;
55 	struct platform_device *canvas_pdev;
56 	struct meson_canvas *canvas;
57 
58 	canvas_node = of_parse_phandle(dev->of_node, "amlogic,canvas", 0);
59 	if (!canvas_node)
60 		return ERR_PTR(-ENODEV);
61 
62 	canvas_pdev = of_find_device_by_node(canvas_node);
63 	if (!canvas_pdev) {
64 		of_node_put(canvas_node);
65 		return ERR_PTR(-EPROBE_DEFER);
66 	}
67 
68 	of_node_put(canvas_node);
69 
70 	/*
71 	 * If priv is NULL, it's probably because the canvas hasn't
72 	 * properly initialized. Bail out with -EINVAL because, in the
73 	 * current state, this driver probe cannot return -EPROBE_DEFER
74 	 */
75 	canvas = dev_get_drvdata(&canvas_pdev->dev);
76 	if (!canvas) {
77 		put_device(&canvas_pdev->dev);
78 		return ERR_PTR(-EINVAL);
79 	}
80 
81 	return canvas;
82 }
83 EXPORT_SYMBOL_GPL(meson_canvas_get);
84 
85 int meson_canvas_config(struct meson_canvas *canvas, u8 canvas_index,
86 			u32 addr, u32 stride, u32 height,
87 			unsigned int wrap,
88 			unsigned int blkmode,
89 			unsigned int endian)
90 {
91 	unsigned long flags;
92 
93 	if (endian && !canvas->supports_endianness) {
94 		dev_err(canvas->dev,
95 			"Endianness is not supported on this SoC\n");
96 		return -EINVAL;
97 	}
98 
99 	spin_lock_irqsave(&canvas->lock, flags);
100 	if (!canvas->used[canvas_index]) {
101 		dev_err(canvas->dev,
102 			"Trying to setup non allocated canvas %u\n",
103 			canvas_index);
104 		spin_unlock_irqrestore(&canvas->lock, flags);
105 		return -EINVAL;
106 	}
107 
108 	canvas_write(canvas, DMC_CAV_LUT_DATAL,
109 		     ((addr + 7) >> 3) |
110 		     (((stride + 7) >> 3) << CANVAS_WIDTH_LBIT));
111 
112 	canvas_write(canvas, DMC_CAV_LUT_DATAH,
113 		     ((((stride + 7) >> 3) >> CANVAS_WIDTH_LWID) <<
114 						CANVAS_WIDTH_HBIT) |
115 		     (height << CANVAS_HEIGHT_BIT) |
116 		     (wrap << CANVAS_WRAP_BIT) |
117 		     (blkmode << CANVAS_BLKMODE_BIT) |
118 		     (endian << CANVAS_ENDIAN_BIT));
119 
120 	canvas_write(canvas, DMC_CAV_LUT_ADDR,
121 		     CANVAS_LUT_WR_EN | canvas_index);
122 
123 	/* Force a read-back to make sure everything is flushed. */
124 	canvas_read(canvas, DMC_CAV_LUT_DATAH);
125 	spin_unlock_irqrestore(&canvas->lock, flags);
126 
127 	return 0;
128 }
129 EXPORT_SYMBOL_GPL(meson_canvas_config);
130 
131 int meson_canvas_alloc(struct meson_canvas *canvas, u8 *canvas_index)
132 {
133 	int i;
134 	unsigned long flags;
135 
136 	spin_lock_irqsave(&canvas->lock, flags);
137 	for (i = 0; i < NUM_CANVAS; ++i) {
138 		if (!canvas->used[i]) {
139 			canvas->used[i] = 1;
140 			spin_unlock_irqrestore(&canvas->lock, flags);
141 			*canvas_index = i;
142 			return 0;
143 		}
144 	}
145 	spin_unlock_irqrestore(&canvas->lock, flags);
146 
147 	dev_err(canvas->dev, "No more canvas available\n");
148 	return -ENODEV;
149 }
150 EXPORT_SYMBOL_GPL(meson_canvas_alloc);
151 
152 int meson_canvas_free(struct meson_canvas *canvas, u8 canvas_index)
153 {
154 	unsigned long flags;
155 
156 	spin_lock_irqsave(&canvas->lock, flags);
157 	if (!canvas->used[canvas_index]) {
158 		dev_err(canvas->dev,
159 			"Trying to free unused canvas %u\n", canvas_index);
160 		spin_unlock_irqrestore(&canvas->lock, flags);
161 		return -EINVAL;
162 	}
163 	canvas->used[canvas_index] = 0;
164 	spin_unlock_irqrestore(&canvas->lock, flags);
165 
166 	return 0;
167 }
168 EXPORT_SYMBOL_GPL(meson_canvas_free);
169 
170 static int meson_canvas_probe(struct platform_device *pdev)
171 {
172 	struct meson_canvas *canvas;
173 	struct device *dev = &pdev->dev;
174 
175 	canvas = devm_kzalloc(dev, sizeof(*canvas), GFP_KERNEL);
176 	if (!canvas)
177 		return -ENOMEM;
178 
179 	canvas->reg_base = devm_platform_ioremap_resource(pdev, 0);
180 	if (IS_ERR(canvas->reg_base))
181 		return PTR_ERR(canvas->reg_base);
182 
183 	canvas->supports_endianness = of_device_get_match_data(dev);
184 
185 	canvas->dev = dev;
186 	spin_lock_init(&canvas->lock);
187 	dev_set_drvdata(dev, canvas);
188 
189 	return 0;
190 }
191 
192 static const struct of_device_id canvas_dt_match[] = {
193 	{ .compatible = "amlogic,meson8-canvas", .data = (void *)false, },
194 	{ .compatible = "amlogic,meson8b-canvas", .data = (void *)false, },
195 	{ .compatible = "amlogic,meson8m2-canvas", .data = (void *)false, },
196 	{ .compatible = "amlogic,canvas", .data = (void *)true, },
197 	{}
198 };
199 MODULE_DEVICE_TABLE(of, canvas_dt_match);
200 
201 static struct platform_driver meson_canvas_driver = {
202 	.probe = meson_canvas_probe,
203 	.driver = {
204 		.name = "amlogic-canvas",
205 		.of_match_table = canvas_dt_match,
206 	},
207 };
208 module_platform_driver(meson_canvas_driver);
209 
210 MODULE_DESCRIPTION("Amlogic Canvas driver");
211 MODULE_AUTHOR("Maxime Jourdan <mjourdan@baylibre.com>");
212 MODULE_LICENSE("GPL");
213