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
canvas_write(struct meson_canvas * canvas,u32 reg,u32 val)42 static void canvas_write(struct meson_canvas *canvas, u32 reg, u32 val)
43 {
44 writel_relaxed(val, canvas->reg_base + reg);
45 }
46
canvas_read(struct meson_canvas * canvas,u32 reg)47 static u32 canvas_read(struct meson_canvas *canvas, u32 reg)
48 {
49 return readl_relaxed(canvas->reg_base + reg);
50 }
51
meson_canvas_get(struct device * dev)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
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)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
meson_canvas_alloc(struct meson_canvas * canvas,u8 * canvas_index)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
meson_canvas_free(struct meson_canvas * canvas,u8 canvas_index)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
meson_canvas_probe(struct platform_device * pdev)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