drivers/video/fbdev/goldfishfb.c

   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
  30 enum {
  31         FB_GET_WIDTH        = 0x00,
  32         FB_GET_HEIGHT       = 0x04,
  33         FB_INT_STATUS       = 0x08,
  34         FB_INT_ENABLE       = 0x0c,
  35         FB_SET_BASE         = 0x10,
  36         FB_SET_ROTATION     = 0x14,
  37         FB_SET_BLANK        = 0x18,
  38         FB_GET_PHYS_WIDTH   = 0x1c,
  39         FB_GET_PHYS_HEIGHT  = 0x20,
  40
  41         FB_INT_VSYNC             = 1U << 0,
  42         FB_INT_BASE_UPDATE_DONE  = 1U << 1
  43 };
  44
  45 struct goldfish_fb {
  46         void __iomem *reg_base;
  47         int irq;
  48         spinlock_t lock;
  49         wait_queue_head_t wait;
  50         int base_update_count;
  51         int rotation;
  52         struct fb_info fb;
  53         u32 cmap[16];
  54 };
  55
  56 static irqreturn_t goldfish_fb_interrupt(int irq, void *dev_id)
  57 {
  58         unsigned long irq_flags;
  59         struct goldfish_fb *fb = dev_id;
  60         u32 status;
  61
  62         spin_lock_irqsave(&fb->lock, irq_flags);
  63         status = readl(fb->reg_base + FB_INT_STATUS);
  64         if (status & FB_INT_BASE_UPDATE_DONE) {
  65                 fb->base_update_count++;
  66                 wake_up(&fb->wait);
  67         }
  68         spin_unlock_irqrestore(&fb->lock, irq_flags);
  69         return status ? IRQ_HANDLED : IRQ_NONE;
  70 }
  71
  72 static inline u32 convert_bitfield(int val, struct fb_bitfield *bf)
  73 {
  74         unsigned int mask = (1 << bf->length) - 1;
  75
  76         return (val >> (16 - bf->length) & mask) << bf->offset;
  77 }
  78
  79 static int
  80 goldfish_fb_setcolreg(unsigned int regno, unsigned int red, unsigned int green,
  81                  unsigned int blue, unsigned int transp, struct fb_info *info)
  82 {
  83         struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
  84
  85         if (regno < 16) {
  86                 fb->cmap[regno] = convert_bitfield(transp, &fb->fb.var.transp) |
  87                                   convert_bitfield(blue, &fb->fb.var.blue) |
  88                                   convert_bitfield(green, &fb->fb.var.green) |
  89                                   convert_bitfield(red, &fb->fb.var.red);
  90                 return 0;
  91         } else {
  92                 return 1;
  93         }
  94 }
  95
  96 static int goldfish_fb_check_var(struct fb_var_screeninfo *var,
  97                                                         struct fb_info *info)
  98 {
  99         if ((var->rotate & 1) != (info->var.rotate & 1)) {
 100                 if ((var->xres != info->var.yres) ||
 101                                 (var->yres != info->var.xres) ||
 102                                 (var->xres_virtual != info->var.yres) ||
 103                                 (var->yres_virtual > info->var.xres * 2) ||
 104                                 (var->yres_virtual < info->var.xres)) {
 105                         return -EINVAL;
 106                 }
 107         } else {
 108                 if ((var->xres != info->var.xres) ||
 109                    (var->yres != info->var.yres) ||
 110                    (var->xres_virtual != info->var.xres) ||
 111                    (var->yres_virtual > info->var.yres * 2) ||
 112                    (var->yres_virtual < info->var.yres)) {
 113                         return -EINVAL;
 114                 }
 115         }
 116         if ((var->xoffset != info->var.xoffset) ||
 117                         (var->bits_per_pixel != info->var.bits_per_pixel) ||
 118                         (var->grayscale != info->var.grayscale)) {
 119                 return -EINVAL;
 120         }
 121         return 0;
 122 }
 123
 124 static int goldfish_fb_set_par(struct fb_info *info)
 125 {
 126         struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
 127         if (fb->rotation != fb->fb.var.rotate) {
 128                 info->fix.line_length = info->var.xres * 2;
 129                 fb->rotation = fb->fb.var.rotate;
 130                 writel(fb->rotation, fb->reg_base + FB_SET_ROTATION);
 131         }
 132         return 0;
 133 }
 134
 135
 136 static int goldfish_fb_pan_display(struct fb_var_screeninfo *var,
 137                                                         struct fb_info *info)
 138 {
 139         unsigned long irq_flags;
 140         int base_update_count;
 141         struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
 142
 143         spin_lock_irqsave(&fb->lock, irq_flags);
 144         base_update_count = fb->base_update_count;
 145         writel(fb->fb.fix.smem_start + fb->fb.var.xres * 2 * var->yoffset,
 146                                                 fb->reg_base + FB_SET_BASE);
 147         spin_unlock_irqrestore(&fb->lock, irq_flags);
 148         wait_event_timeout(fb->wait,
 149                         fb->base_update_count != base_update_count, HZ / 15);
 150         if (fb->base_update_count == base_update_count)
 151                 pr_err("goldfish_fb_pan_display: timeout waiting for base update\n");
 152         return 0;
 153 }
 154
 155 static int goldfish_fb_blank(int blank, struct fb_info *info)
 156 {
 157         struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb);
 158         switch (blank) {
 159         case FB_BLANK_NORMAL:
 160                 writel(1, fb->reg_base + FB_SET_BLANK);
 161                 break;
 162         case FB_BLANK_UNBLANK:
 163                 writel(0, fb->reg_base + FB_SET_BLANK);
 164                 break;
 165         }
 166         return 0;
 167 }
 168
 169 static struct fb_ops goldfish_fb_ops = {
 170         .owner          = THIS_MODULE,
 171         .fb_check_var   = goldfish_fb_check_var,
 172         .fb_set_par     = goldfish_fb_set_par,
 173         .fb_setcolreg   = goldfish_fb_setcolreg,
 174         .fb_pan_display = goldfish_fb_pan_display,
 175         .fb_blank       = goldfish_fb_blank,
 176         .fb_fillrect    = cfb_fillrect,
 177         .fb_copyarea    = cfb_copyarea,
 178         .fb_imageblit   = cfb_imageblit,
 179 };
 180
 181
 182 static int goldfish_fb_probe(struct platform_device *pdev)
 183 {
 184         int ret;
 185         struct resource *r;
 186         struct goldfish_fb *fb;
 187         size_t framesize;
 188         u32 width, height;
 189         dma_addr_t fbpaddr;
 190
 191         fb = kzalloc(sizeof(*fb), GFP_KERNEL);
 192         if (fb == NULL) {
 193                 ret = -ENOMEM;
 194                 goto err_fb_alloc_failed;
 195         }
 196         spin_lock_init(&fb->lock);
 197         init_waitqueue_head(&fb->wait);
 198         platform_set_drvdata(pdev, fb);
 199
 200         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 201         if (r == NULL) {
 202                 ret = -ENODEV;
 203                 goto err_no_io_base;
 204         }
 205         fb->reg_base = ioremap(r->start, PAGE_SIZE);
 206         if (fb->reg_base == NULL) {
 207                 ret = -ENOMEM;
 208                 goto err_no_io_base;
 209         }
 210
 211         fb->irq = platform_get_irq(pdev, 0);
 212         if (fb->irq <= 0) {
 213                 ret = -ENODEV;
 214                 goto err_no_irq;
 215         }
 216
 217         width = readl(fb->reg_base + FB_GET_WIDTH);
 218         height = readl(fb->reg_base + FB_GET_HEIGHT);
 219
 220         fb->fb.fbops            = &goldfish_fb_ops;
 221         fb->fb.flags            = FBINFO_FLAG_DEFAULT;
 222         fb->fb.pseudo_palette   = fb->cmap;
 223         fb->fb.fix.type         = FB_TYPE_PACKED_PIXELS;
 224         fb->fb.fix.visual = FB_VISUAL_TRUECOLOR;
 225         fb->fb.fix.line_length = width * 2;
 226         fb->fb.fix.accel        = FB_ACCEL_NONE;
 227         fb->fb.fix.ypanstep = 1;
 228
 229         fb->fb.var.xres         = width;
 230         fb->fb.var.yres         = height;
 231         fb->fb.var.xres_virtual = width;
 232         fb->fb.var.yres_virtual = height * 2;
 233         fb->fb.var.bits_per_pixel = 16;
 234         fb->fb.var.activate     = FB_ACTIVATE_NOW;
 235         fb->fb.var.height       = readl(fb->reg_base + FB_GET_PHYS_HEIGHT);
 236         fb->fb.var.width        = readl(fb->reg_base + FB_GET_PHYS_WIDTH);
 237         fb->fb.var.pixclock     = 10000;
 238
 239         fb->fb.var.red.offset = 11;
 240         fb->fb.var.red.length = 5;
 241         fb->fb.var.green.offset = 5;
 242         fb->fb.var.green.length = 6;
 243         fb->fb.var.blue.offset = 0;
 244         fb->fb.var.blue.length = 5;
 245
 246         framesize = width * height * 2 * 2;
 247         fb->fb.screen_base = (char __force __iomem *)dma_alloc_coherent(
 248                                                 &pdev->dev, framesize,
 249                                                 &fbpaddr, GFP_KERNEL);
 250         pr_debug("allocating frame buffer %d * %d, got %p\n",
 251                                         width, height, fb->fb.screen_base);
 252         if (fb->fb.screen_base == NULL) {
 253                 ret = -ENOMEM;
 254                 goto err_alloc_screen_base_failed;
 255         }
 256         fb->fb.fix.smem_start = fbpaddr;
 257         fb->fb.fix.smem_len = framesize;
 258
 259         ret = fb_set_var(&fb->fb, &fb->fb.var);
 260         if (ret)
 261                 goto err_fb_set_var_failed;
 262
 263         ret = request_irq(fb->irq, goldfish_fb_interrupt, IRQF_SHARED,
 264                                                         pdev->name, fb);
 265         if (ret)
 266                 goto err_request_irq_failed;
 267
 268         writel(FB_INT_BASE_UPDATE_DONE, fb->reg_base + FB_INT_ENABLE);
 269         goldfish_fb_pan_display(&fb->fb.var, &fb->fb); /* updates base */
 270
 271         ret = register_framebuffer(&fb->fb);
 272         if (ret)
 273                 goto err_register_framebuffer_failed;
 274         return 0;
 275
 276 err_register_framebuffer_failed:
 277         free_irq(fb->irq, fb);
 278 err_request_irq_failed:
 279 err_fb_set_var_failed:
 280         dma_free_coherent(&pdev->dev, framesize,
 281                                 (void *)fb->fb.screen_base,
 282                                 fb->fb.fix.smem_start);
 283 err_alloc_screen_base_failed:
 284 err_no_irq:
 285         iounmap(fb->reg_base);
 286 err_no_io_base:
 287         kfree(fb);
 288 err_fb_alloc_failed:
 289         return ret;
 290 }
 291
 292 static int goldfish_fb_remove(struct platform_device *pdev)
 293 {
 294         size_t framesize;
 295         struct goldfish_fb *fb = platform_get_drvdata(pdev);
 296
 297         framesize = fb->fb.var.xres_virtual * fb->fb.var.yres_virtual * 2;
 298         unregister_framebuffer(&fb->fb);
 299         free_irq(fb->irq, fb);
 300
 301         dma_free_coherent(&pdev->dev, framesize, (void *)fb->fb.screen_base,
 302                                                 fb->fb.fix.smem_start);
 303         iounmap(fb->reg_base);
 304         kfree(fb);
 305         return 0;
 306 }
 307
 308 static const struct of_device_id goldfish_fb_of_match[] = {
 309         { .compatible = "google,goldfish-fb", },
 310         {},
 311 };
 312 MODULE_DEVICE_TABLE(of, goldfish_fb_of_match);
 313
 314 static struct platform_driver goldfish_fb_driver = {
 315         .probe          = goldfish_fb_probe,
 316         .remove         = goldfish_fb_remove,
 317         .driver = {
 318                 .name = "goldfish_fb",
 319                 .of_match_table = goldfish_fb_of_match,
 320         }
 321 };
 322
 323 module_platform_driver(goldfish_fb_driver);
 324
 325 MODULE_LICENSE("GPL v2");