1 /*
2 * Copyright (C) 2007 Google, Inc.
3 * Copyright (C) 2012 Intel, Inc.
4 *
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 */
15
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/errno.h>
20 #include <linux/string.h>
21 #include <linux/slab.h>
22 #include <linux/delay.h>
23 #include <linux/mm.h>
24 #include <linux/fb.h>
25 #include <linux/init.h>
26 #include <linux/interrupt.h>
27 #include <linux/ioport.h>
28 #include <linux/platform_device.h>
29 #include <linux/acpi.h>
30
31 enum {
32 FB_GET_WIDTH = 0x00,
33 FB_GET_HEIGHT = 0x04,
34 FB_INT_STATUS = 0x08,
35 FB_INT_ENABLE = 0x0c,
36 FB_SET_BASE = 0x10,
37 FB_SET_ROTATION = 0x14,
38 FB_SET_BLANK = 0x18,
39 FB_GET_PHYS_WIDTH = 0x1c,
40 FB_GET_PHYS_HEIGHT = 0x20,
41
42 FB_INT_VSYNC = 1U << 0,
43 FB_INT_BASE_UPDATE_DONE = 1U << 1
44 };
45
46 struct goldfish_fb {
47 void __iomem *reg_base;
48 int irq;
49 spinlock_t lock;
50 wait_queue_head_t wait;
51 int base_update_count;
52 int rotation;
53 struct fb_info fb;
54 u32 cmap[16];
55 };
56
goldfish_fb_interrupt(int irq,void * dev_id)57 static irqreturn_t goldfish_fb_interrupt(int irq, void *dev_id)
58 {
59 unsigned long irq_flags;
60 struct goldfish_fb *fb = dev_id;
61 u32 status;
62
63 spin_lock_irqsave(&fb->lock, irq_flags);
64 status = readl(fb->reg_base + FB_INT_STATUS);
65 if (status & FB_INT_BASE_UPDATE_DONE) {
66 fb->base_update_count++;
67 wake_up(&fb->wait);
68 }
69 spin_unlock_irqrestore(&fb->lock, irq_flags);
70 return status ? IRQ_HANDLED : IRQ_NONE;
71 }
72
convert_bitfield(int val,struct fb_bitfield * bf)73 static inline u32 convert_bitfield(int val, struct fb_bitfield *bf)
74 {
75 unsigned int mask = (1 << bf->length) - 1;
76
77 return (val >> (16 - bf->length) & mask) << bf->offset;
78 }
79
80 static int
goldfish_fb_setcolreg(unsigned int regno,unsigned int red,unsigned int green,unsigned int blue,unsigned int transp,struct fb_info * info)81 goldfish_fb_setcolreg(unsigned int regno, unsigned int red, unsigned int green,
82 unsigned int blue, unsigned int transp, struct fb_info *info)
83 {
84 struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
85
86 if (regno < 16) {
87 fb->cmap[regno] = convert_bitfield(transp, &fb->fb.var.transp) |
88 convert_bitfield(blue, &fb->fb.var.blue) |
89 convert_bitfield(green, &fb->fb.var.green) |
90 convert_bitfield(red, &fb->fb.var.red);
91 return 0;
92 } else {
93 return 1;
94 }
95 }
96
goldfish_fb_check_var(struct fb_var_screeninfo * var,struct fb_info * info)97 static int goldfish_fb_check_var(struct fb_var_screeninfo *var,
98 struct fb_info *info)
99 {
100 if ((var->rotate & 1) != (info->var.rotate & 1)) {
101 if ((var->xres != info->var.yres) ||
102 (var->yres != info->var.xres) ||
103 (var->xres_virtual != info->var.yres) ||
104 (var->yres_virtual > info->var.xres * 2) ||
105 (var->yres_virtual < info->var.xres)) {
106 return -EINVAL;
107 }
108 } else {
109 if ((var->xres != info->var.xres) ||
110 (var->yres != info->var.yres) ||
111 (var->xres_virtual != info->var.xres) ||
112 (var->yres_virtual > info->var.yres * 2) ||
113 (var->yres_virtual < info->var.yres)) {
114 return -EINVAL;
115 }
116 }
117 if ((var->xoffset != info->var.xoffset) ||
118 (var->bits_per_pixel != info->var.bits_per_pixel) ||
119 (var->grayscale != info->var.grayscale)) {
120 return -EINVAL;
121 }
122 return 0;
123 }
124
goldfish_fb_set_par(struct fb_info * info)125 static int goldfish_fb_set_par(struct fb_info *info)
126 {
127 struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
128 if (fb->rotation != fb->fb.var.rotate) {
129 info->fix.line_length = info->var.xres * 2;
130 fb->rotation = fb->fb.var.rotate;
131 writel(fb->rotation, fb->reg_base + FB_SET_ROTATION);
132 }
133 return 0;
134 }
135
136
goldfish_fb_pan_display(struct fb_var_screeninfo * var,struct fb_info * info)137 static int goldfish_fb_pan_display(struct fb_var_screeninfo *var,
138 struct fb_info *info)
139 {
140 unsigned long irq_flags;
141 int base_update_count;
142 struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
143
144 spin_lock_irqsave(&fb->lock, irq_flags);
145 base_update_count = fb->base_update_count;
146 writel(fb->fb.fix.smem_start + fb->fb.var.xres * 2 * var->yoffset,
147 fb->reg_base + FB_SET_BASE);
148 spin_unlock_irqrestore(&fb->lock, irq_flags);
149 wait_event_timeout(fb->wait,
150 fb->base_update_count != base_update_count, HZ / 15);
151 if (fb->base_update_count == base_update_count)
152 pr_err("goldfish_fb_pan_display: timeout waiting for base update\n");
153 return 0;
154 }
155
goldfish_fb_blank(int blank,struct fb_info * info)156 static int goldfish_fb_blank(int blank, struct fb_info *info)
157 {
158 struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
159 switch (blank) {
160 case FB_BLANK_NORMAL:
161 writel(1, fb->reg_base + FB_SET_BLANK);
162 break;
163 case FB_BLANK_UNBLANK:
164 writel(0, fb->reg_base + FB_SET_BLANK);
165 break;
166 }
167 return 0;
168 }
169
170 static struct fb_ops goldfish_fb_ops = {
171 .owner = THIS_MODULE,
172 .fb_check_var = goldfish_fb_check_var,
173 .fb_set_par = goldfish_fb_set_par,
174 .fb_setcolreg = goldfish_fb_setcolreg,
175 .fb_pan_display = goldfish_fb_pan_display,
176 .fb_blank = goldfish_fb_blank,
177 .fb_fillrect = cfb_fillrect,
178 .fb_copyarea = cfb_copyarea,
179 .fb_imageblit = cfb_imageblit,
180 };
181
182
goldfish_fb_probe(struct platform_device * pdev)183 static int goldfish_fb_probe(struct platform_device *pdev)
184 {
185 int ret;
186 struct resource *r;
187 struct goldfish_fb *fb;
188 size_t framesize;
189 u32 width, height;
190 dma_addr_t fbpaddr;
191
192 fb = kzalloc(sizeof(*fb), GFP_KERNEL);
193 if (fb == NULL) {
194 ret = -ENOMEM;
195 goto err_fb_alloc_failed;
196 }
197 spin_lock_init(&fb->lock);
198 init_waitqueue_head(&fb->wait);
199 platform_set_drvdata(pdev, fb);
200
201 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
202 if (r == NULL) {
203 ret = -ENODEV;
204 goto err_no_io_base;
205 }
206 fb->reg_base = ioremap(r->start, PAGE_SIZE);
207 if (fb->reg_base == NULL) {
208 ret = -ENOMEM;
209 goto err_no_io_base;
210 }
211
212 fb->irq = platform_get_irq(pdev, 0);
213 if (fb->irq <= 0) {
214 ret = -ENODEV;
215 goto err_no_irq;
216 }
217
218 width = readl(fb->reg_base + FB_GET_WIDTH);
219 height = readl(fb->reg_base + FB_GET_HEIGHT);
220
221 fb->fb.fbops = &goldfish_fb_ops;
222 fb->fb.flags = FBINFO_FLAG_DEFAULT;
223 fb->fb.pseudo_palette = fb->cmap;
224 fb->fb.fix.type = FB_TYPE_PACKED_PIXELS;
225 fb->fb.fix.visual = FB_VISUAL_TRUECOLOR;
226 fb->fb.fix.line_length = width * 2;
227 fb->fb.fix.accel = FB_ACCEL_NONE;
228 fb->fb.fix.ypanstep = 1;
229
230 fb->fb.var.xres = width;
231 fb->fb.var.yres = height;
232 fb->fb.var.xres_virtual = width;
233 fb->fb.var.yres_virtual = height * 2;
234 fb->fb.var.bits_per_pixel = 16;
235 fb->fb.var.activate = FB_ACTIVATE_NOW;
236 fb->fb.var.height = readl(fb->reg_base + FB_GET_PHYS_HEIGHT);
237 fb->fb.var.width = readl(fb->reg_base + FB_GET_PHYS_WIDTH);
238 fb->fb.var.pixclock = 0;
239
240 fb->fb.var.red.offset = 11;
241 fb->fb.var.red.length = 5;
242 fb->fb.var.green.offset = 5;
243 fb->fb.var.green.length = 6;
244 fb->fb.var.blue.offset = 0;
245 fb->fb.var.blue.length = 5;
246
247 framesize = width * height * 2 * 2;
248 fb->fb.screen_base = (char __force __iomem *)dma_alloc_coherent(
249 &pdev->dev, framesize,
250 &fbpaddr, GFP_KERNEL);
251 pr_debug("allocating frame buffer %d * %d, got %p\n",
252 width, height, fb->fb.screen_base);
253 if (fb->fb.screen_base == NULL) {
254 ret = -ENOMEM;
255 goto err_alloc_screen_base_failed;
256 }
257 fb->fb.fix.smem_start = fbpaddr;
258 fb->fb.fix.smem_len = framesize;
259
260 ret = fb_set_var(&fb->fb, &fb->fb.var);
261 if (ret)
262 goto err_fb_set_var_failed;
263
264 ret = request_irq(fb->irq, goldfish_fb_interrupt, IRQF_SHARED,
265 pdev->name, fb);
266 if (ret)
267 goto err_request_irq_failed;
268
269 writel(FB_INT_BASE_UPDATE_DONE, fb->reg_base + FB_INT_ENABLE);
270 goldfish_fb_pan_display(&fb->fb.var, &fb->fb); /* updates base */
271
272 ret = register_framebuffer(&fb->fb);
273 if (ret)
274 goto err_register_framebuffer_failed;
275 return 0;
276
277 err_register_framebuffer_failed:
278 free_irq(fb->irq, fb);
279 err_request_irq_failed:
280 err_fb_set_var_failed:
281 dma_free_coherent(&pdev->dev, framesize,
282 (void *)fb->fb.screen_base,
283 fb->fb.fix.smem_start);
284 err_alloc_screen_base_failed:
285 err_no_irq:
286 iounmap(fb->reg_base);
287 err_no_io_base:
288 kfree(fb);
289 err_fb_alloc_failed:
290 return ret;
291 }
292
goldfish_fb_remove(struct platform_device * pdev)293 static int goldfish_fb_remove(struct platform_device *pdev)
294 {
295 size_t framesize;
296 struct goldfish_fb *fb = platform_get_drvdata(pdev);
297
298 framesize = fb->fb.var.xres_virtual * fb->fb.var.yres_virtual * 2;
299 unregister_framebuffer(&fb->fb);
300 free_irq(fb->irq, fb);
301
302 dma_free_coherent(&pdev->dev, framesize, (void *)fb->fb.screen_base,
303 fb->fb.fix.smem_start);
304 iounmap(fb->reg_base);
305 kfree(fb);
306 return 0;
307 }
308
309 static const struct of_device_id goldfish_fb_of_match[] = {
310 { .compatible = "google,goldfish-fb", },
311 {},
312 };
313 MODULE_DEVICE_TABLE(of, goldfish_fb_of_match);
314
315 static const struct acpi_device_id goldfish_fb_acpi_match[] = {
316 { "GFSH0004", 0 },
317 { },
318 };
319 MODULE_DEVICE_TABLE(acpi, goldfish_fb_acpi_match);
320
321 static struct platform_driver goldfish_fb_driver = {
322 .probe = goldfish_fb_probe,
323 .remove = goldfish_fb_remove,
324 .driver = {
325 .name = "goldfish_fb",
326 .of_match_table = goldfish_fb_of_match,
327 .acpi_match_table = ACPI_PTR(goldfish_fb_acpi_match),
328 }
329 };
330
331 module_platform_driver(goldfish_fb_driver);
332
333 MODULE_LICENSE("GPL v2");
334