xref: /openbmc/linux/drivers/soc/amlogic/meson-canvas.c (revision 05cf4fe738242183f1237f1b3a28b4479348c0a1)
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/regmap.h>
12 #include <linux/soc/amlogic/meson-canvas.h>
13 #include <linux/of_address.h>
14 #include <linux/of_platform.h>
15 #include <linux/io.h>
16 
17 #define NUM_CANVAS 256
18 
19 /* DMC Registers */
20 #define DMC_CAV_LUT_DATAL	0x00
21 	#define CANVAS_WIDTH_LBIT	29
22 	#define CANVAS_WIDTH_LWID	3
23 #define DMC_CAV_LUT_DATAH	0x04
24 	#define CANVAS_WIDTH_HBIT	0
25 	#define CANVAS_HEIGHT_BIT	9
26 	#define CANVAS_WRAP_BIT		22
27 	#define CANVAS_BLKMODE_BIT	24
28 	#define CANVAS_ENDIAN_BIT	26
29 #define DMC_CAV_LUT_ADDR	0x08
30 	#define CANVAS_LUT_WR_EN	BIT(9)
31 	#define CANVAS_LUT_RD_EN	BIT(8)
32 
33 struct meson_canvas {
34 	struct device *dev;
35 	void __iomem *reg_base;
36 	spinlock_t lock; /* canvas device lock */
37 	u8 used[NUM_CANVAS];
38 };
39 
40 static void canvas_write(struct meson_canvas *canvas, u32 reg, u32 val)
41 {
42 	writel_relaxed(val, canvas->reg_base + reg);
43 }
44 
45 static u32 canvas_read(struct meson_canvas *canvas, u32 reg)
46 {
47 	return readl_relaxed(canvas->reg_base + reg);
48 }
49 
50 struct meson_canvas *meson_canvas_get(struct device *dev)
51 {
52 	struct device_node *canvas_node;
53 	struct platform_device *canvas_pdev;
54 
55 	canvas_node = of_parse_phandle(dev->of_node, "amlogic,canvas", 0);
56 	if (!canvas_node)
57 		return ERR_PTR(-ENODEV);
58 
59 	canvas_pdev = of_find_device_by_node(canvas_node);
60 	if (!canvas_pdev)
61 		return ERR_PTR(-EPROBE_DEFER);
62 
63 	return dev_get_drvdata(&canvas_pdev->dev);
64 }
65 EXPORT_SYMBOL_GPL(meson_canvas_get);
66 
67 int meson_canvas_config(struct meson_canvas *canvas, u8 canvas_index,
68 			u32 addr, u32 stride, u32 height,
69 			unsigned int wrap,
70 			unsigned int blkmode,
71 			unsigned int endian)
72 {
73 	unsigned long flags;
74 
75 	spin_lock_irqsave(&canvas->lock, flags);
76 	if (!canvas->used[canvas_index]) {
77 		dev_err(canvas->dev,
78 			"Trying to setup non allocated canvas %u\n",
79 			canvas_index);
80 		spin_unlock_irqrestore(&canvas->lock, flags);
81 		return -EINVAL;
82 	}
83 
84 	canvas_write(canvas, DMC_CAV_LUT_DATAL,
85 		     ((addr + 7) >> 3) |
86 		     (((stride + 7) >> 3) << CANVAS_WIDTH_LBIT));
87 
88 	canvas_write(canvas, DMC_CAV_LUT_DATAH,
89 		     ((((stride + 7) >> 3) >> CANVAS_WIDTH_LWID) <<
90 						CANVAS_WIDTH_HBIT) |
91 		     (height << CANVAS_HEIGHT_BIT) |
92 		     (wrap << CANVAS_WRAP_BIT) |
93 		     (blkmode << CANVAS_BLKMODE_BIT) |
94 		     (endian << CANVAS_ENDIAN_BIT));
95 
96 	canvas_write(canvas, DMC_CAV_LUT_ADDR,
97 		     CANVAS_LUT_WR_EN | canvas_index);
98 
99 	/* Force a read-back to make sure everything is flushed. */
100 	canvas_read(canvas, DMC_CAV_LUT_DATAH);
101 	spin_unlock_irqrestore(&canvas->lock, flags);
102 
103 	return 0;
104 }
105 EXPORT_SYMBOL_GPL(meson_canvas_config);
106 
107 int meson_canvas_alloc(struct meson_canvas *canvas, u8 *canvas_index)
108 {
109 	int i;
110 	unsigned long flags;
111 
112 	spin_lock_irqsave(&canvas->lock, flags);
113 	for (i = 0; i < NUM_CANVAS; ++i) {
114 		if (!canvas->used[i]) {
115 			canvas->used[i] = 1;
116 			spin_unlock_irqrestore(&canvas->lock, flags);
117 			*canvas_index = i;
118 			return 0;
119 		}
120 	}
121 	spin_unlock_irqrestore(&canvas->lock, flags);
122 
123 	dev_err(canvas->dev, "No more canvas available\n");
124 	return -ENODEV;
125 }
126 EXPORT_SYMBOL_GPL(meson_canvas_alloc);
127 
128 int meson_canvas_free(struct meson_canvas *canvas, u8 canvas_index)
129 {
130 	unsigned long flags;
131 
132 	spin_lock_irqsave(&canvas->lock, flags);
133 	if (!canvas->used[canvas_index]) {
134 		dev_err(canvas->dev,
135 			"Trying to free unused canvas %u\n", canvas_index);
136 		spin_unlock_irqrestore(&canvas->lock, flags);
137 		return -EINVAL;
138 	}
139 	canvas->used[canvas_index] = 0;
140 	spin_unlock_irqrestore(&canvas->lock, flags);
141 
142 	return 0;
143 }
144 EXPORT_SYMBOL_GPL(meson_canvas_free);
145 
146 static int meson_canvas_probe(struct platform_device *pdev)
147 {
148 	struct resource *res;
149 	struct meson_canvas *canvas;
150 	struct device *dev = &pdev->dev;
151 
152 	canvas = devm_kzalloc(dev, sizeof(*canvas), GFP_KERNEL);
153 	if (!canvas)
154 		return -ENOMEM;
155 
156 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
157 	canvas->reg_base = devm_ioremap_resource(dev, res);
158 	if (IS_ERR(canvas->reg_base))
159 		return PTR_ERR(canvas->reg_base);
160 
161 	canvas->dev = dev;
162 	spin_lock_init(&canvas->lock);
163 	dev_set_drvdata(dev, canvas);
164 
165 	return 0;
166 }
167 
168 static const struct of_device_id canvas_dt_match[] = {
169 	{ .compatible = "amlogic,canvas" },
170 	{}
171 };
172 MODULE_DEVICE_TABLE(of, canvas_dt_match);
173 
174 static struct platform_driver meson_canvas_driver = {
175 	.probe = meson_canvas_probe,
176 	.driver = {
177 		.name = "amlogic-canvas",
178 		.of_match_table = canvas_dt_match,
179 	},
180 };
181 module_platform_driver(meson_canvas_driver);
182 
183 MODULE_DESCRIPTION("Amlogic Canvas driver");
184 MODULE_AUTHOR("Maxime Jourdan <mjourdan@baylibre.com>");
185 MODULE_LICENSE("GPL");
186