1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) 2007 Google, Inc. |
4 | * Copyright (C) 2012 Intel, Inc. |
5 | */ |
6 | |
7 | #include <linux/module.h> |
8 | #include <linux/kernel.h> |
9 | #include <linux/dma-mapping.h> |
10 | #include <linux/errno.h> |
11 | #include <linux/string.h> |
12 | #include <linux/slab.h> |
13 | #include <linux/delay.h> |
14 | #include <linux/mm.h> |
15 | #include <linux/fb.h> |
16 | #include <linux/init.h> |
17 | #include <linux/interrupt.h> |
18 | #include <linux/ioport.h> |
19 | #include <linux/platform_device.h> |
20 | #include <linux/acpi.h> |
21 | |
22 | enum { |
23 | FB_GET_WIDTH = 0x00, |
24 | FB_GET_HEIGHT = 0x04, |
25 | FB_INT_STATUS = 0x08, |
26 | FB_INT_ENABLE = 0x0c, |
27 | FB_SET_BASE = 0x10, |
28 | FB_SET_ROTATION = 0x14, |
29 | FB_SET_BLANK = 0x18, |
30 | FB_GET_PHYS_WIDTH = 0x1c, |
31 | FB_GET_PHYS_HEIGHT = 0x20, |
32 | |
33 | FB_INT_VSYNC = 1U << 0, |
34 | FB_INT_BASE_UPDATE_DONE = 1U << 1 |
35 | }; |
36 | |
37 | struct goldfish_fb { |
38 | void __iomem *reg_base; |
39 | int irq; |
40 | spinlock_t lock; |
41 | wait_queue_head_t wait; |
42 | int base_update_count; |
43 | int rotation; |
44 | struct fb_info fb; |
45 | u32 cmap[16]; |
46 | }; |
47 | |
48 | static irqreturn_t goldfish_fb_interrupt(int irq, void *dev_id) |
49 | { |
50 | unsigned long irq_flags; |
51 | struct goldfish_fb *fb = dev_id; |
52 | u32 status; |
53 | |
54 | spin_lock_irqsave(&fb->lock, irq_flags); |
55 | status = readl(addr: fb->reg_base + FB_INT_STATUS); |
56 | if (status & FB_INT_BASE_UPDATE_DONE) { |
57 | fb->base_update_count++; |
58 | wake_up(&fb->wait); |
59 | } |
60 | spin_unlock_irqrestore(lock: &fb->lock, flags: irq_flags); |
61 | return status ? IRQ_HANDLED : IRQ_NONE; |
62 | } |
63 | |
64 | static inline u32 convert_bitfield(int val, struct fb_bitfield *bf) |
65 | { |
66 | unsigned int mask = (1 << bf->length) - 1; |
67 | |
68 | return (val >> (16 - bf->length) & mask) << bf->offset; |
69 | } |
70 | |
71 | static int |
72 | goldfish_fb_setcolreg(unsigned int regno, unsigned int red, unsigned int green, |
73 | unsigned int blue, unsigned int transp, struct fb_info *info) |
74 | { |
75 | struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb); |
76 | |
77 | if (regno < 16) { |
78 | fb->cmap[regno] = convert_bitfield(val: transp, bf: &fb->fb.var.transp) | |
79 | convert_bitfield(val: blue, bf: &fb->fb.var.blue) | |
80 | convert_bitfield(val: green, bf: &fb->fb.var.green) | |
81 | convert_bitfield(val: red, bf: &fb->fb.var.red); |
82 | return 0; |
83 | } else { |
84 | return 1; |
85 | } |
86 | } |
87 | |
88 | static int goldfish_fb_check_var(struct fb_var_screeninfo *var, |
89 | struct fb_info *info) |
90 | { |
91 | if ((var->rotate & 1) != (info->var.rotate & 1)) { |
92 | if ((var->xres != info->var.yres) || |
93 | (var->yres != info->var.xres) || |
94 | (var->xres_virtual != info->var.yres) || |
95 | (var->yres_virtual > info->var.xres * 2) || |
96 | (var->yres_virtual < info->var.xres)) { |
97 | return -EINVAL; |
98 | } |
99 | } else { |
100 | if ((var->xres != info->var.xres) || |
101 | (var->yres != info->var.yres) || |
102 | (var->xres_virtual != info->var.xres) || |
103 | (var->yres_virtual > info->var.yres * 2) || |
104 | (var->yres_virtual < info->var.yres)) { |
105 | return -EINVAL; |
106 | } |
107 | } |
108 | if ((var->xoffset != info->var.xoffset) || |
109 | (var->bits_per_pixel != info->var.bits_per_pixel) || |
110 | (var->grayscale != info->var.grayscale)) { |
111 | return -EINVAL; |
112 | } |
113 | return 0; |
114 | } |
115 | |
116 | static int goldfish_fb_set_par(struct fb_info *info) |
117 | { |
118 | struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb); |
119 | |
120 | if (fb->rotation != fb->fb.var.rotate) { |
121 | info->fix.line_length = info->var.xres * 2; |
122 | fb->rotation = fb->fb.var.rotate; |
123 | writel(val: fb->rotation, addr: fb->reg_base + FB_SET_ROTATION); |
124 | } |
125 | return 0; |
126 | } |
127 | |
128 | |
129 | static int goldfish_fb_pan_display(struct fb_var_screeninfo *var, |
130 | struct fb_info *info) |
131 | { |
132 | unsigned long irq_flags; |
133 | int base_update_count; |
134 | struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb); |
135 | |
136 | spin_lock_irqsave(&fb->lock, irq_flags); |
137 | base_update_count = fb->base_update_count; |
138 | writel(val: fb->fb.fix.smem_start + fb->fb.var.xres * 2 * var->yoffset, |
139 | addr: fb->reg_base + FB_SET_BASE); |
140 | spin_unlock_irqrestore(lock: &fb->lock, flags: irq_flags); |
141 | wait_event_timeout(fb->wait, |
142 | fb->base_update_count != base_update_count, HZ / 15); |
143 | if (fb->base_update_count == base_update_count) |
144 | pr_err("%s: timeout waiting for base update\n" , __func__); |
145 | return 0; |
146 | } |
147 | |
148 | static int goldfish_fb_blank(int blank, struct fb_info *info) |
149 | { |
150 | struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb); |
151 | |
152 | switch (blank) { |
153 | case FB_BLANK_NORMAL: |
154 | writel(val: 1, addr: fb->reg_base + FB_SET_BLANK); |
155 | break; |
156 | case FB_BLANK_UNBLANK: |
157 | writel(val: 0, addr: fb->reg_base + FB_SET_BLANK); |
158 | break; |
159 | } |
160 | return 0; |
161 | } |
162 | |
163 | static const struct fb_ops goldfish_fb_ops = { |
164 | .owner = THIS_MODULE, |
165 | FB_DEFAULT_IOMEM_OPS, |
166 | .fb_check_var = goldfish_fb_check_var, |
167 | .fb_set_par = goldfish_fb_set_par, |
168 | .fb_setcolreg = goldfish_fb_setcolreg, |
169 | .fb_pan_display = goldfish_fb_pan_display, |
170 | .fb_blank = goldfish_fb_blank, |
171 | }; |
172 | |
173 | |
174 | static int goldfish_fb_probe(struct platform_device *pdev) |
175 | { |
176 | int ret; |
177 | struct resource *r; |
178 | struct goldfish_fb *fb; |
179 | size_t framesize; |
180 | u32 width, height; |
181 | dma_addr_t fbpaddr; |
182 | |
183 | fb = kzalloc(size: sizeof(*fb), GFP_KERNEL); |
184 | if (fb == NULL) { |
185 | ret = -ENOMEM; |
186 | goto err_fb_alloc_failed; |
187 | } |
188 | spin_lock_init(&fb->lock); |
189 | init_waitqueue_head(&fb->wait); |
190 | platform_set_drvdata(pdev, data: fb); |
191 | |
192 | r = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
193 | if (r == NULL) { |
194 | ret = -ENODEV; |
195 | goto err_no_io_base; |
196 | } |
197 | fb->reg_base = ioremap(offset: r->start, PAGE_SIZE); |
198 | if (fb->reg_base == NULL) { |
199 | ret = -ENOMEM; |
200 | goto err_no_io_base; |
201 | } |
202 | |
203 | fb->irq = platform_get_irq(pdev, 0); |
204 | if (fb->irq < 0) { |
205 | ret = fb->irq; |
206 | goto err_no_irq; |
207 | } |
208 | |
209 | width = readl(addr: fb->reg_base + FB_GET_WIDTH); |
210 | height = readl(addr: fb->reg_base + FB_GET_HEIGHT); |
211 | |
212 | fb->fb.fbops = &goldfish_fb_ops; |
213 | fb->fb.pseudo_palette = fb->cmap; |
214 | fb->fb.fix.type = FB_TYPE_PACKED_PIXELS; |
215 | fb->fb.fix.visual = FB_VISUAL_TRUECOLOR; |
216 | fb->fb.fix.line_length = width * 2; |
217 | fb->fb.fix.accel = FB_ACCEL_NONE; |
218 | fb->fb.fix.ypanstep = 1; |
219 | |
220 | fb->fb.var.xres = width; |
221 | fb->fb.var.yres = height; |
222 | fb->fb.var.xres_virtual = width; |
223 | fb->fb.var.yres_virtual = height * 2; |
224 | fb->fb.var.bits_per_pixel = 16; |
225 | fb->fb.var.activate = FB_ACTIVATE_NOW; |
226 | fb->fb.var.height = readl(addr: fb->reg_base + FB_GET_PHYS_HEIGHT); |
227 | fb->fb.var.width = readl(addr: fb->reg_base + FB_GET_PHYS_WIDTH); |
228 | fb->fb.var.pixclock = 0; |
229 | |
230 | fb->fb.var.red.offset = 11; |
231 | fb->fb.var.red.length = 5; |
232 | fb->fb.var.green.offset = 5; |
233 | fb->fb.var.green.length = 6; |
234 | fb->fb.var.blue.offset = 0; |
235 | fb->fb.var.blue.length = 5; |
236 | |
237 | framesize = width * height * 2 * 2; |
238 | fb->fb.screen_base = (char __force __iomem *)dma_alloc_coherent( |
239 | dev: &pdev->dev, size: framesize, |
240 | dma_handle: &fbpaddr, GFP_KERNEL); |
241 | pr_debug("allocating frame buffer %d * %d, got %p\n" , |
242 | width, height, fb->fb.screen_base); |
243 | if (fb->fb.screen_base == NULL) { |
244 | ret = -ENOMEM; |
245 | goto err_alloc_screen_base_failed; |
246 | } |
247 | fb->fb.fix.smem_start = fbpaddr; |
248 | fb->fb.fix.smem_len = framesize; |
249 | |
250 | ret = fb_set_var(info: &fb->fb, var: &fb->fb.var); |
251 | if (ret) |
252 | goto err_fb_set_var_failed; |
253 | |
254 | ret = request_irq(irq: fb->irq, handler: goldfish_fb_interrupt, IRQF_SHARED, |
255 | name: pdev->name, dev: fb); |
256 | if (ret) |
257 | goto err_request_irq_failed; |
258 | |
259 | writel(val: FB_INT_BASE_UPDATE_DONE, addr: fb->reg_base + FB_INT_ENABLE); |
260 | goldfish_fb_pan_display(var: &fb->fb.var, info: &fb->fb); /* updates base */ |
261 | |
262 | ret = register_framebuffer(fb_info: &fb->fb); |
263 | if (ret) |
264 | goto err_register_framebuffer_failed; |
265 | return 0; |
266 | |
267 | err_register_framebuffer_failed: |
268 | free_irq(fb->irq, fb); |
269 | err_request_irq_failed: |
270 | err_fb_set_var_failed: |
271 | dma_free_coherent(dev: &pdev->dev, size: framesize, |
272 | cpu_addr: (void *)fb->fb.screen_base, |
273 | dma_handle: fb->fb.fix.smem_start); |
274 | err_alloc_screen_base_failed: |
275 | err_no_irq: |
276 | iounmap(addr: fb->reg_base); |
277 | err_no_io_base: |
278 | kfree(objp: fb); |
279 | err_fb_alloc_failed: |
280 | return ret; |
281 | } |
282 | |
283 | static void goldfish_fb_remove(struct platform_device *pdev) |
284 | { |
285 | size_t framesize; |
286 | struct goldfish_fb *fb = platform_get_drvdata(pdev); |
287 | |
288 | framesize = fb->fb.var.xres_virtual * fb->fb.var.yres_virtual * 2; |
289 | unregister_framebuffer(fb_info: &fb->fb); |
290 | free_irq(fb->irq, fb); |
291 | |
292 | dma_free_coherent(dev: &pdev->dev, size: framesize, cpu_addr: (void *)fb->fb.screen_base, |
293 | dma_handle: fb->fb.fix.smem_start); |
294 | iounmap(addr: fb->reg_base); |
295 | kfree(objp: fb); |
296 | } |
297 | |
298 | static const struct of_device_id goldfish_fb_of_match[] = { |
299 | { .compatible = "google,goldfish-fb" , }, |
300 | {}, |
301 | }; |
302 | MODULE_DEVICE_TABLE(of, goldfish_fb_of_match); |
303 | |
304 | #ifdef CONFIG_ACPI |
305 | static const struct acpi_device_id goldfish_fb_acpi_match[] = { |
306 | { "GFSH0004" , 0 }, |
307 | { }, |
308 | }; |
309 | MODULE_DEVICE_TABLE(acpi, goldfish_fb_acpi_match); |
310 | #endif |
311 | |
312 | static struct platform_driver goldfish_fb_driver = { |
313 | .probe = goldfish_fb_probe, |
314 | .remove_new = goldfish_fb_remove, |
315 | .driver = { |
316 | .name = "goldfish_fb" , |
317 | .of_match_table = goldfish_fb_of_match, |
318 | .acpi_match_table = ACPI_PTR(goldfish_fb_acpi_match), |
319 | } |
320 | }; |
321 | |
322 | module_platform_driver(goldfish_fb_driver); |
323 | |
324 | MODULE_LICENSE("GPL v2" ); |
325 | |