drivers/video/fbdev/xilinxfb.c

   1 /*
   2  * Xilinx TFT frame buffer driver
   3  *
   4  * Author: MontaVista Software, Inc.
   5  *         source@mvista.com
   6  *
   7  * 2002-2007 (c) MontaVista Software, Inc.
   8  * 2007 (c) Secret Lab Technologies, Ltd.
   9  * 2009 (c) Xilinx Inc.
  10  *
  11  * This file is licensed under the terms of the GNU General Public License
  12  * version 2.  This program is licensed "as is" without any warranty of any
  13  * kind, whether express or implied.
  14  */
  15
  16 /*
  17  * This driver was based on au1100fb.c by MontaVista rewritten for 2.6
  18  * by Embedded Alley Solutions <source@embeddedalley.com>, which in turn
  19  * was based on skeletonfb.c, Skeleton for a frame buffer device by
  20  * Geert Uytterhoeven.
  21  */
  22
  23 #include <linux/device.h>
  24 #include <linux/module.h>
  25 #include <linux/kernel.h>
  26 #include <linux/errno.h>
  27 #include <linux/string.h>
  28 #include <linux/mm.h>
  29 #include <linux/fb.h>
  30 #include <linux/init.h>
  31 #include <linux/dma-mapping.h>
  32 #include <linux/of_device.h>
  33 #include <linux/of_platform.h>
  34 #include <linux/of_address.h>
  35 #include <linux/io.h>
  36 #include <linux/slab.h>
  37
  38 #ifdef CONFIG_PPC_DCR
  39 #include <asm/dcr.h>
  40 #endif
  41
  42 #define DRIVER_NAME             "xilinxfb"
  43
  44
  45 /*
  46  * Xilinx calls it "TFT LCD Controller" though it can also be used for
  47  * the VGA port on the Xilinx ML40x board. This is a hardware display
  48  * controller for a 640x480 resolution TFT or VGA screen.
  49  *
  50  * The interface to the framebuffer is nice and simple.  There are two
  51  * control registers.  The first tells the LCD interface where in memory
  52  * the frame buffer is (only the 11 most significant bits are used, so
  53  * don't start thinking about scrolling).  The second allows the LCD to
  54  * be turned on or off as well as rotated 180 degrees.
  55  *
  56  * In case of direct BUS access the second control register will be at
  57  * an offset of 4 as compared to the DCR access where the offset is 1
  58  * i.e. REG_CTRL. So this is taken care in the function
  59  * xilinx_fb_out32 where it left shifts the offset 2 times in case of
  60  * direct BUS access.
  61  */
  62 #define NUM_REGS        2
  63 #define REG_FB_ADDR     0
  64 #define REG_CTRL        1
  65 #define REG_CTRL_ENABLE  0x0001
  66 #define REG_CTRL_ROTATE  0x0002
  67
  68 /*
  69  * The hardware only handles a single mode: 640x480 24 bit true
  70  * color. Each pixel gets a word (32 bits) of memory.  Within each word,
  71  * the 8 most significant bits are ignored, the next 8 bits are the red
  72  * level, the next 8 bits are the green level and the 8 least
  73  * significant bits are the blue level.  Each row of the LCD uses 1024
  74  * words, but only the first 640 pixels are displayed with the other 384
  75  * words being ignored.  There are 480 rows.
  76  */
  77 #define BYTES_PER_PIXEL 4
  78 #define BITS_PER_PIXEL  (BYTES_PER_PIXEL * 8)
  79
  80 #define RED_SHIFT       16
  81 #define GREEN_SHIFT     8
  82 #define BLUE_SHIFT      0
  83
  84 #define PALETTE_ENTRIES_NO      16      /* passed to fb_alloc_cmap() */
  85
  86 /* ML300/403 reference design framebuffer driver platform data struct */
  87 struct xilinxfb_platform_data {
  88         u32 rotate_screen;      /* Flag to rotate display 180 degrees */
  89         u32 screen_height_mm;   /* Physical dimensions of screen in mm */
  90         u32 screen_width_mm;
  91         u32 xres, yres;         /* resolution of screen in pixels */
  92         u32 xvirt, yvirt;       /* resolution of memory buffer */
  93
  94         /* Physical address of framebuffer memory; If non-zero, driver
  95         * will use provided memory address instead of allocating one from
  96         * the consistent pool. */
  97         u32 fb_phys;
  98 };
  99
 100 /*
 101  * Default xilinxfb configuration
 102  */
 103 static struct xilinxfb_platform_data xilinx_fb_default_pdata = {
 104         .xres = 640,
 105         .yres = 480,
 106         .xvirt = 1024,
 107         .yvirt = 480,
 108 };
 109
 110 /*
 111  * Here are the default fb_fix_screeninfo and fb_var_screeninfo structures
 112  */
 113 static struct fb_fix_screeninfo xilinx_fb_fix = {
 114         .id =           "Xilinx",
 115         .type =         FB_TYPE_PACKED_PIXELS,
 116         .visual =       FB_VISUAL_TRUECOLOR,
 117         .accel =        FB_ACCEL_NONE
 118 };
 119
 120 static struct fb_var_screeninfo xilinx_fb_var = {
 121         .bits_per_pixel =       BITS_PER_PIXEL,
 122
 123         .red =          { RED_SHIFT, 8, 0 },
 124         .green =        { GREEN_SHIFT, 8, 0 },
 125         .blue =         { BLUE_SHIFT, 8, 0 },
 126         .transp =       { 0, 0, 0 },
 127
 128         .activate =     FB_ACTIVATE_NOW
 129 };
 130
 131
 132 #define BUS_ACCESS_FLAG         0x1 /* 1 = BUS, 0 = DCR */
 133 #define LITTLE_ENDIAN_ACCESS    0x2 /* LITTLE ENDIAN IO functions */
 134
 135 struct xilinxfb_drvdata {
 136
 137         struct fb_info  info;           /* FB driver info record */
 138
 139         phys_addr_t     regs_phys;      /* phys. address of the control
 140                                                 registers */
 141         void __iomem    *regs;          /* virt. address of the control
 142                                                 registers */
 143 #ifdef CONFIG_PPC_DCR
 144         dcr_host_t      dcr_host;
 145         unsigned int    dcr_len;
 146 #endif
 147         void            *fb_virt;       /* virt. address of the frame buffer */
 148         dma_addr_t      fb_phys;        /* phys. address of the frame buffer */
 149         int             fb_alloced;     /* Flag, was the fb memory alloced? */
 150
 151         u8              flags;          /* features of the driver */
 152
 153         u32             reg_ctrl_default;
 154
 155         u32             pseudo_palette[PALETTE_ENTRIES_NO];
 156                                         /* Fake palette of 16 colors */
 157 };
 158
 159 #define to_xilinxfb_drvdata(_info) \
 160         container_of(_info, struct xilinxfb_drvdata, info)
 161
 162 /*
 163  * The XPS TFT Controller can be accessed through BUS or DCR interface.
 164  * To perform the read/write on the registers we need to check on
 165  * which bus its connected and call the appropriate write API.
 166  */
 167 static void xilinx_fb_out32(struct xilinxfb_drvdata *drvdata, u32 offset,
 168                                 u32 val)
 169 {
 170         if (drvdata->flags & BUS_ACCESS_FLAG) {
 171                 if (drvdata->flags & LITTLE_ENDIAN_ACCESS)
 172                         iowrite32(val, drvdata->regs + (offset << 2));
 173                 else
 174                         iowrite32be(val, drvdata->regs + (offset << 2));
 175         }
 176 #ifdef CONFIG_PPC_DCR
 177         else
 178                 dcr_write(drvdata->dcr_host, offset, val);
 179 #endif
 180 }
 181
 182 static u32 xilinx_fb_in32(struct xilinxfb_drvdata *drvdata, u32 offset)
 183 {
 184         if (drvdata->flags & BUS_ACCESS_FLAG) {
 185                 if (drvdata->flags & LITTLE_ENDIAN_ACCESS)
 186                         return ioread32(drvdata->regs + (offset << 2));
 187                 else
 188                         return ioread32be(drvdata->regs + (offset << 2));
 189         }
 190 #ifdef CONFIG_PPC_DCR
 191         else
 192                 return dcr_read(drvdata->dcr_host, offset);
 193 #endif
 194         return 0;
 195 }
 196
 197 static int
 198 xilinx_fb_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue,
 199         unsigned transp, struct fb_info *fbi)
 200 {
 201         u32 *palette = fbi->pseudo_palette;
 202
 203         if (regno >= PALETTE_ENTRIES_NO)
 204                 return -EINVAL;
 205
 206         if (fbi->var.grayscale) {
 207                 /* Convert color to grayscale.
 208                  * grayscale = 0.30*R + 0.59*G + 0.11*B */
 209                 red = green = blue =
 210                         (red * 77 + green * 151 + blue * 28 + 127) >> 8;
 211         }
 212
 213         /* fbi->fix.visual is always FB_VISUAL_TRUECOLOR */
 214
 215         /* We only handle 8 bits of each color. */
 216         red >>= 8;
 217         green >>= 8;
 218         blue >>= 8;
 219         palette[regno] = (red << RED_SHIFT) | (green << GREEN_SHIFT) |
 220                          (blue << BLUE_SHIFT);
 221
 222         return 0;
 223 }
 224
 225 static int
 226 xilinx_fb_blank(int blank_mode, struct fb_info *fbi)
 227 {
 228         struct xilinxfb_drvdata *drvdata = to_xilinxfb_drvdata(fbi);
 229
 230         switch (blank_mode) {
 231         case FB_BLANK_UNBLANK:
 232                 /* turn on panel */
 233                 xilinx_fb_out32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);
 234                 break;
 235
 236         case FB_BLANK_NORMAL:
 237         case FB_BLANK_VSYNC_SUSPEND:
 238         case FB_BLANK_HSYNC_SUSPEND:
 239         case FB_BLANK_POWERDOWN:
 240                 /* turn off panel */
 241                 xilinx_fb_out32(drvdata, REG_CTRL, 0);
 242         default:
 243                 break;
 244
 245         }
 246         return 0; /* success */
 247 }
 248
 249 static struct fb_ops xilinxfb_ops =
 250 {
 251         .owner                  = THIS_MODULE,
 252         .fb_setcolreg           = xilinx_fb_setcolreg,
 253         .fb_blank               = xilinx_fb_blank,
 254         .fb_fillrect            = cfb_fillrect,
 255         .fb_copyarea            = cfb_copyarea,
 256         .fb_imageblit           = cfb_imageblit,
 257 };
 258
 259 /* ---------------------------------------------------------------------
 260  * Bus independent setup/teardown
 261  */
 262
 263 static int xilinxfb_assign(struct platform_device *pdev,
 264                            struct xilinxfb_drvdata *drvdata,
 265                            struct xilinxfb_platform_data *pdata)
 266 {
 267         int rc;
 268         struct device *dev = &pdev->dev;
 269         int fbsize = pdata->xvirt * pdata->yvirt * BYTES_PER_PIXEL;
 270
 271         if (drvdata->flags & BUS_ACCESS_FLAG) {
 272                 struct resource *res;
 273
 274                 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 275                 drvdata->regs = devm_ioremap_resource(&pdev->dev, res);
 276                 if (IS_ERR(drvdata->regs))
 277                         return PTR_ERR(drvdata->regs);
 278
 279                 drvdata->regs_phys = res->start;
 280         }
 281
 282         /* Allocate the framebuffer memory */
 283         if (pdata->fb_phys) {
 284                 drvdata->fb_phys = pdata->fb_phys;
 285                 drvdata->fb_virt = ioremap(pdata->fb_phys, fbsize);
 286         } else {
 287                 drvdata->fb_alloced = 1;
 288                 drvdata->fb_virt = dma_alloc_coherent(dev, PAGE_ALIGN(fbsize),
 289                                         &drvdata->fb_phys, GFP_KERNEL);
 290         }
 291
 292         if (!drvdata->fb_virt) {
 293                 dev_err(dev, "Could not allocate frame buffer memory\n");
 294                 return -ENOMEM;
 295         }
 296
 297         /* Clear (turn to black) the framebuffer */
 298         memset_io((void __iomem *)drvdata->fb_virt, 0, fbsize);
 299
 300         /* Tell the hardware where the frame buffer is */
 301         xilinx_fb_out32(drvdata, REG_FB_ADDR, drvdata->fb_phys);
 302         rc = xilinx_fb_in32(drvdata, REG_FB_ADDR);
 303         /* Endianess detection */
 304         if (rc != drvdata->fb_phys) {
 305                 drvdata->flags |= LITTLE_ENDIAN_ACCESS;
 306                 xilinx_fb_out32(drvdata, REG_FB_ADDR, drvdata->fb_phys);
 307         }
 308
 309         /* Turn on the display */
 310         drvdata->reg_ctrl_default = REG_CTRL_ENABLE;
 311         if (pdata->rotate_screen)
 312                 drvdata->reg_ctrl_default |= REG_CTRL_ROTATE;
 313         xilinx_fb_out32(drvdata, REG_CTRL,
 314                                         drvdata->reg_ctrl_default);
 315
 316         /* Fill struct fb_info */
 317         drvdata->info.device = dev;
 318         drvdata->info.screen_base = (void __iomem *)drvdata->fb_virt;
 319         drvdata->info.fbops = &xilinxfb_ops;
 320         drvdata->info.fix = xilinx_fb_fix;
 321         drvdata->info.fix.smem_start = drvdata->fb_phys;
 322         drvdata->info.fix.smem_len = fbsize;
 323         drvdata->info.fix.line_length = pdata->xvirt * BYTES_PER_PIXEL;
 324
 325         drvdata->info.pseudo_palette = drvdata->pseudo_palette;
 326         drvdata->info.flags = FBINFO_DEFAULT;
 327         drvdata->info.var = xilinx_fb_var;
 328         drvdata->info.var.height = pdata->screen_height_mm;
 329         drvdata->info.var.width = pdata->screen_width_mm;
 330         drvdata->info.var.xres = pdata->xres;
 331         drvdata->info.var.yres = pdata->yres;
 332         drvdata->info.var.xres_virtual = pdata->xvirt;
 333         drvdata->info.var.yres_virtual = pdata->yvirt;
 334
 335         /* Allocate a colour map */
 336         rc = fb_alloc_cmap(&drvdata->info.cmap, PALETTE_ENTRIES_NO, 0);
 337         if (rc) {
 338                 dev_err(dev, "Fail to allocate colormap (%d entries)\n",
 339                         PALETTE_ENTRIES_NO);
 340                 goto err_cmap;
 341         }
 342
 343         /* Register new frame buffer */
 344         rc = register_framebuffer(&drvdata->info);
 345         if (rc) {
 346                 dev_err(dev, "Could not register frame buffer\n");
 347                 goto err_regfb;
 348         }
 349
 350         if (drvdata->flags & BUS_ACCESS_FLAG) {
 351                 /* Put a banner in the log (for DEBUG) */
 352                 dev_dbg(dev, "regs: phys=%pa, virt=%p\n",
 353                         &drvdata->regs_phys, drvdata->regs);
 354         }
 355         /* Put a banner in the log (for DEBUG) */
 356         dev_dbg(dev, "fb: phys=%llx, virt=%p, size=%x\n",
 357                 (unsigned long long)drvdata->fb_phys, drvdata->fb_virt, fbsize);
 358
 359         return 0;       /* success */
 360
 361 err_regfb:
 362         fb_dealloc_cmap(&drvdata->info.cmap);
 363
 364 err_cmap:
 365         if (drvdata->fb_alloced)
 366                 dma_free_coherent(dev, PAGE_ALIGN(fbsize), drvdata->fb_virt,
 367                         drvdata->fb_phys);
 368         else
 369                 iounmap(drvdata->fb_virt);
 370
 371         /* Turn off the display */
 372         xilinx_fb_out32(drvdata, REG_CTRL, 0);
 373
 374         return rc;
 375 }
 376
 377 static int xilinxfb_release(struct device *dev)
 378 {
 379         struct xilinxfb_drvdata *drvdata = dev_get_drvdata(dev);
 380
 381 #if !defined(CONFIG_FRAMEBUFFER_CONSOLE) && defined(CONFIG_LOGO)
 382         xilinx_fb_blank(VESA_POWERDOWN, &drvdata->info);
 383 #endif
 384
 385         unregister_framebuffer(&drvdata->info);
 386
 387         fb_dealloc_cmap(&drvdata->info.cmap);
 388
 389         if (drvdata->fb_alloced)
 390                 dma_free_coherent(dev, PAGE_ALIGN(drvdata->info.fix.smem_len),
 391                                   drvdata->fb_virt, drvdata->fb_phys);
 392         else
 393                 iounmap(drvdata->fb_virt);
 394
 395         /* Turn off the display */
 396         xilinx_fb_out32(drvdata, REG_CTRL, 0);
 397
 398 #ifdef CONFIG_PPC_DCR
 399         /* Release the resources, as allocated based on interface */
 400         if (!(drvdata->flags & BUS_ACCESS_FLAG))
 401                 dcr_unmap(drvdata->dcr_host, drvdata->dcr_len);
 402 #endif
 403
 404         return 0;
 405 }
 406
 407 /* ---------------------------------------------------------------------
 408  * OF bus binding
 409  */
 410
 411 static int xilinxfb_of_probe(struct platform_device *pdev)
 412 {
 413         const u32 *prop;
 414         u32 tft_access = 0;
 415         struct xilinxfb_platform_data pdata;
 416         int size;
 417         struct xilinxfb_drvdata *drvdata;
 418
 419         /* Copy with the default pdata (not a ptr reference!) */
 420         pdata = xilinx_fb_default_pdata;
 421
 422         /* Allocate the driver data region */
 423         drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
 424         if (!drvdata)
 425                 return -ENOMEM;
 426
 427         /*
 428          * To check whether the core is connected directly to DCR or BUS
 429          * interface and initialize the tft_access accordingly.
 430          */
 431         of_property_read_u32(pdev->dev.of_node, "xlnx,dcr-splb-slave-if",
 432                              &tft_access);
 433
 434         /*
 435          * Fill the resource structure if its direct BUS interface
 436          * otherwise fill the dcr_host structure.
 437          */
 438         if (tft_access) {
 439                 drvdata->flags |= BUS_ACCESS_FLAG;
 440         }
 441 #ifdef CONFIG_PPC_DCR
 442         else {
 443                 int start;
 444                 start = dcr_resource_start(pdev->dev.of_node, 0);
 445                 drvdata->dcr_len = dcr_resource_len(pdev->dev.of_node, 0);
 446                 drvdata->dcr_host = dcr_map(pdev->dev.of_node, start, drvdata->dcr_len);
 447                 if (!DCR_MAP_OK(drvdata->dcr_host)) {
 448                         dev_err(&pdev->dev, "invalid DCR address\n");
 449                         return -ENODEV;
 450                 }
 451         }
 452 #endif
 453
 454         prop = of_get_property(pdev->dev.of_node, "phys-size", &size);
 455         if ((prop) && (size >= sizeof(u32)*2)) {
 456                 pdata.screen_width_mm = prop[0];
 457                 pdata.screen_height_mm = prop[1];
 458         }
 459
 460         prop = of_get_property(pdev->dev.of_node, "resolution", &size);
 461         if ((prop) && (size >= sizeof(u32)*2)) {
 462                 pdata.xres = prop[0];
 463                 pdata.yres = prop[1];
 464         }
 465
 466         prop = of_get_property(pdev->dev.of_node, "virtual-resolution", &size);
 467         if ((prop) && (size >= sizeof(u32)*2)) {
 468                 pdata.xvirt = prop[0];
 469                 pdata.yvirt = prop[1];
 470         }
 471
 472         if (of_find_property(pdev->dev.of_node, "rotate-display", NULL))
 473                 pdata.rotate_screen = 1;
 474
 475         dev_set_drvdata(&pdev->dev, drvdata);
 476         return xilinxfb_assign(pdev, drvdata, &pdata);
 477 }
 478
 479 static int xilinxfb_of_remove(struct platform_device *op)
 480 {
 481         return xilinxfb_release(&op->dev);
 482 }
 483
 484 /* Match table for of_platform binding */
 485 static struct of_device_id xilinxfb_of_match[] = {
 486         { .compatible = "xlnx,xps-tft-1.00.a", },
 487         { .compatible = "xlnx,xps-tft-2.00.a", },
 488         { .compatible = "xlnx,xps-tft-2.01.a", },
 489         { .compatible = "xlnx,plb-tft-cntlr-ref-1.00.a", },
 490         { .compatible = "xlnx,plb-dvi-cntlr-ref-1.00.c", },
 491         {},
 492 };
 493 MODULE_DEVICE_TABLE(of, xilinxfb_of_match);
 494
 495 static struct platform_driver xilinxfb_of_driver = {
 496         .probe = xilinxfb_of_probe,
 497         .remove = xilinxfb_of_remove,
 498         .driver = {
 499                 .name = DRIVER_NAME,
 500                 .of_match_table = xilinxfb_of_match,
 501         },
 502 };
 503
 504 module_platform_driver(xilinxfb_of_driver);
 505
 506 MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>");
 507 MODULE_DESCRIPTION("Xilinx TFT frame buffer driver");
 508 MODULE_LICENSE("GPL");