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