drivers/video/fbdev/sh7760fb.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * SH7760/SH7763 LCDC Framebuffer driver.
   4  *
   5  * (c) 2006-2008 MSC Vertriebsges.m.b.H.,
   6  *             Manuel Lauss <mano@roarinelk.homelinux.net>
   7  * (c) 2008 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
   8  *
   9  * PLEASE HAVE A LOOK AT Documentation/fb/sh7760fb.rst!
  10  *
  11  * Thanks to Siegfried Schaefer <s.schaefer at schaefer-edv.de>
  12  *     for his original source and testing!
  13  *
  14  * sh7760_setcolreg get from drivers/video/sh_mobile_lcdcfb.c
  15  */
  16
  17 #include <linux/completion.h>
  18 #include <linux/delay.h>
  19 #include <linux/dma-mapping.h>
  20 #include <linux/fb.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/io.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/slab.h>
  27
  28 #include <asm/sh7760fb.h>
  29
  30 struct sh7760fb_par {
  31         void __iomem *base;
  32         int irq;
  33
  34         struct sh7760fb_platdata *pd;   /* display information */
  35
  36         dma_addr_t fbdma;       /* physical address */
  37
  38         int rot;                /* rotation enabled? */
  39
  40         u32 pseudo_palette[16];
  41
  42         struct platform_device *dev;
  43         struct resource *ioarea;
  44         struct completion vsync;        /* vsync irq event */
  45 };
  46
  47 static irqreturn_t sh7760fb_irq(int irq, void *data)
  48 {
  49         struct completion *c = data;
  50
  51         complete(c);
  52
  53         return IRQ_HANDLED;
  54 }
  55
  56 /* wait_for_lps - wait until power supply has reached a certain state. */
  57 static int wait_for_lps(struct sh7760fb_par *par, int val)
  58 {
  59         int i = 100;
  60         while (--i && ((ioread16(par->base + LDPMMR) & 3) != val))
  61                 msleep(1);
  62
  63         if (i <= 0)
  64                 return -ETIMEDOUT;
  65
  66         return 0;
  67 }
  68
  69 /* en/disable the LCDC */
  70 static int sh7760fb_blank(int blank, struct fb_info *info)
  71 {
  72         struct sh7760fb_par *par = info->par;
  73         struct sh7760fb_platdata *pd = par->pd;
  74         unsigned short cntr = ioread16(par->base + LDCNTR);
  75         unsigned short intr = ioread16(par->base + LDINTR);
  76         int lps;
  77
  78         if (blank == FB_BLANK_UNBLANK) {
  79                 intr |= VINT_START;
  80                 cntr = LDCNTR_DON2 | LDCNTR_DON;
  81                 lps = 3;
  82         } else {
  83                 intr &= ~VINT_START;
  84                 cntr = LDCNTR_DON2;
  85                 lps = 0;
  86         }
  87
  88         if (pd->blank)
  89                 pd->blank(blank);
  90
  91         iowrite16(intr, par->base + LDINTR);
  92         iowrite16(cntr, par->base + LDCNTR);
  93
  94         return wait_for_lps(par, lps);
  95 }
  96
  97 static int sh7760_setcolreg (u_int regno,
  98         u_int red, u_int green, u_int blue,
  99         u_int transp, struct fb_info *info)
 100 {
 101         u32 *palette = info->pseudo_palette;
 102
 103         if (regno >= 16)
 104                 return -EINVAL;
 105
 106         /* only FB_VISUAL_TRUECOLOR supported */
 107
 108         red >>= 16 - info->var.red.length;
 109         green >>= 16 - info->var.green.length;
 110         blue >>= 16 - info->var.blue.length;
 111         transp >>= 16 - info->var.transp.length;
 112
 113         palette[regno] = (red << info->var.red.offset) |
 114                 (green << info->var.green.offset) |
 115                 (blue << info->var.blue.offset) |
 116                 (transp << info->var.transp.offset);
 117
 118         return 0;
 119 }
 120
 121 static int sh7760fb_get_color_info(struct fb_info *info,
 122                                    u16 lddfr, int *bpp, int *gray)
 123 {
 124         int lbpp, lgray;
 125
 126         lgray = lbpp = 0;
 127
 128         switch (lddfr & LDDFR_COLOR_MASK) {
 129         case LDDFR_1BPP_MONO:
 130                 lgray = 1;
 131                 lbpp = 1;
 132                 break;
 133         case LDDFR_2BPP_MONO:
 134                 lgray = 1;
 135                 lbpp = 2;
 136                 break;
 137         case LDDFR_4BPP_MONO:
 138                 lgray = 1;
 139                 fallthrough;
 140         case LDDFR_4BPP:
 141                 lbpp = 4;
 142                 break;
 143         case LDDFR_6BPP_MONO:
 144                 lgray = 1;
 145                 fallthrough;
 146         case LDDFR_8BPP:
 147                 lbpp = 8;
 148                 break;
 149         case LDDFR_16BPP_RGB555:
 150         case LDDFR_16BPP_RGB565:
 151                 lbpp = 16;
 152                 lgray = 0;
 153                 break;
 154         default:
 155                 fb_dbg(info, "unsupported LDDFR bit depth.\n");
 156                 return -EINVAL;
 157         }
 158
 159         if (bpp)
 160                 *bpp = lbpp;
 161         if (gray)
 162                 *gray = lgray;
 163
 164         return 0;
 165 }
 166
 167 static int sh7760fb_check_var(struct fb_var_screeninfo *var,
 168                               struct fb_info *info)
 169 {
 170         struct fb_fix_screeninfo *fix = &info->fix;
 171         struct sh7760fb_par *par = info->par;
 172         int ret, bpp;
 173
 174         /* get color info from register value */
 175         ret = sh7760fb_get_color_info(info, par->pd->lddfr, &bpp, NULL);
 176         if (ret)
 177                 return ret;
 178
 179         var->bits_per_pixel = bpp;
 180
 181         if ((var->grayscale) && (var->bits_per_pixel == 1))
 182                 fix->visual = FB_VISUAL_MONO10;
 183         else if (var->bits_per_pixel >= 15)
 184                 fix->visual = FB_VISUAL_TRUECOLOR;
 185         else
 186                 fix->visual = FB_VISUAL_PSEUDOCOLOR;
 187
 188         /* TODO: add some more validation here */
 189         return 0;
 190 }
 191
 192 /*
 193  * sh7760fb_set_par - set videomode.
 194  *
 195  * NOTE: The rotation, grayscale and DSTN codepaths are
 196  *     totally untested!
 197  */
 198 static int sh7760fb_set_par(struct fb_info *info)
 199 {
 200         struct sh7760fb_par *par = info->par;
 201         struct fb_videomode *vm = par->pd->def_mode;
 202         unsigned long sbase, dstn_off, ldsarl, stride;
 203         unsigned short hsynp, hsynw, htcn, hdcn;
 204         unsigned short vsynp, vsynw, vtln, vdln;
 205         unsigned short lddfr, ldmtr;
 206         int ret, bpp, gray;
 207
 208         par->rot = par->pd->rotate;
 209
 210         /* rotate only works with xres <= 320 */
 211         if (par->rot && (vm->xres > 320)) {
 212                 fb_dbg(info, "rotation disabled due to display size\n");
 213                 par->rot = 0;
 214         }
 215
 216         /* calculate LCDC reg vals from display parameters */
 217         hsynp = vm->right_margin + vm->xres;
 218         hsynw = vm->hsync_len;
 219         htcn = vm->left_margin + hsynp + hsynw;
 220         hdcn = vm->xres;
 221         vsynp = vm->lower_margin + vm->yres;
 222         vsynw = vm->vsync_len;
 223         vtln = vm->upper_margin + vsynp + vsynw;
 224         vdln = vm->yres;
 225
 226         /* get color info from register value */
 227         ret = sh7760fb_get_color_info(info, par->pd->lddfr, &bpp, &gray);
 228         if (ret)
 229                 return ret;
 230
 231         fb_dbg(info, "%dx%d %dbpp %s (orientation %s)\n", hdcn,
 232                 vdln, bpp, gray ? "grayscale" : "color",
 233                 par->rot ? "rotated" : "normal");
 234
 235 #ifdef CONFIG_CPU_LITTLE_ENDIAN
 236         lddfr = par->pd->lddfr | (1 << 8);
 237 #else
 238         lddfr = par->pd->lddfr & ~(1 << 8);
 239 #endif
 240
 241         ldmtr = par->pd->ldmtr;
 242
 243         if (!(vm->sync & FB_SYNC_HOR_HIGH_ACT))
 244                 ldmtr |= LDMTR_CL1POL;
 245         if (!(vm->sync & FB_SYNC_VERT_HIGH_ACT))
 246                 ldmtr |= LDMTR_FLMPOL;
 247
 248         /* shut down LCDC before changing display parameters */
 249         sh7760fb_blank(FB_BLANK_POWERDOWN, info);
 250
 251         iowrite16(par->pd->ldickr, par->base + LDICKR); /* pixclock */
 252         iowrite16(ldmtr, par->base + LDMTR);    /* polarities */
 253         iowrite16(lddfr, par->base + LDDFR);    /* color/depth */
 254         iowrite16((par->rot ? 1 << 13 : 0), par->base + LDSMR); /* rotate */
 255         iowrite16(par->pd->ldpmmr, par->base + LDPMMR); /* Power Management */
 256         iowrite16(par->pd->ldpspr, par->base + LDPSPR); /* Power Supply Ctrl */
 257
 258         /* display resolution */
 259         iowrite16(((htcn >> 3) - 1) | (((hdcn >> 3) - 1) << 8),
 260                   par->base + LDHCNR);
 261         iowrite16(vdln - 1, par->base + LDVDLNR);
 262         iowrite16(vtln - 1, par->base + LDVTLNR);
 263         /* h/v sync signals */
 264         iowrite16((vsynp - 1) | ((vsynw - 1) << 12), par->base + LDVSYNR);
 265         iowrite16(((hsynp >> 3) - 1) | (((hsynw >> 3) - 1) << 12),
 266                   par->base + LDHSYNR);
 267         /* AC modulation sig */
 268         iowrite16(par->pd->ldaclnr, par->base + LDACLNR);
 269
 270         stride = (par->rot) ? vtln : hdcn;
 271         if (!gray)
 272                 stride *= (bpp + 7) >> 3;
 273         else {
 274                 if (bpp == 1)
 275                         stride >>= 3;
 276                 else if (bpp == 2)
 277                         stride >>= 2;
 278                 else if (bpp == 4)
 279                         stride >>= 1;
 280                 /* 6 bpp == 8 bpp */
 281         }
 282
 283         /* if rotated, stride must be power of 2 */
 284         if (par->rot) {
 285                 unsigned long bit = 1 << 31;
 286                 while (bit) {
 287                         if (stride & bit)
 288                                 break;
 289                         bit >>= 1;
 290                 }
 291                 if (stride & ~bit)
 292                         stride = bit << 1;      /* not P-o-2, round up */
 293         }
 294         iowrite16(stride, par->base + LDLAOR);
 295
 296         /* set display mem start address */
 297         sbase = (unsigned long)par->fbdma;
 298         if (par->rot)
 299                 sbase += (hdcn - 1) * stride;
 300
 301         iowrite32(sbase, par->base + LDSARU);
 302
 303         /*
 304          * for DSTN need to set address for lower half.
 305          * I (mlau) don't know which address to set it to,
 306          * so I guessed at (stride * yres/2).
 307          */
 308         if (((ldmtr & 0x003f) >= LDMTR_DSTN_MONO_8) &&
 309             ((ldmtr & 0x003f) <= LDMTR_DSTN_COLOR_16)) {
 310
 311                 fb_dbg(info, " ***** DSTN untested! *****\n");
 312
 313                 dstn_off = stride;
 314                 if (par->rot)
 315                         dstn_off *= hdcn >> 1;
 316                 else
 317                         dstn_off *= vdln >> 1;
 318
 319                 ldsarl = sbase + dstn_off;
 320         } else
 321                 ldsarl = 0;
 322
 323         iowrite32(ldsarl, par->base + LDSARL);  /* mem for lower half of DSTN */
 324
 325         info->fix.line_length = stride;
 326
 327         sh7760fb_check_var(&info->var, info);
 328
 329         sh7760fb_blank(FB_BLANK_UNBLANK, info); /* panel on! */
 330
 331         fb_dbg(info, "hdcn  : %6d htcn  : %6d\n", hdcn, htcn);
 332         fb_dbg(info, "hsynw : %6d hsynp : %6d\n", hsynw, hsynp);
 333         fb_dbg(info, "vdln  : %6d vtln  : %6d\n", vdln, vtln);
 334         fb_dbg(info, "vsynw : %6d vsynp : %6d\n", vsynw, vsynp);
 335         fb_dbg(info, "clksrc: %6d clkdiv: %6d\n",
 336                 (par->pd->ldickr >> 12) & 3, par->pd->ldickr & 0x1f);
 337         fb_dbg(info, "ldpmmr: 0x%04x ldpspr: 0x%04x\n", par->pd->ldpmmr,
 338                 par->pd->ldpspr);
 339         fb_dbg(info, "ldmtr : 0x%04x lddfr : 0x%04x\n", ldmtr, lddfr);
 340         fb_dbg(info, "ldlaor: %ld\n", stride);
 341         fb_dbg(info, "ldsaru: 0x%08lx ldsarl: 0x%08lx\n", sbase, ldsarl);
 342
 343         return 0;
 344 }
 345
 346 static const struct fb_ops sh7760fb_ops = {
 347         .owner = THIS_MODULE,
 348         FB_DEFAULT_IOMEM_OPS,
 349         .fb_blank = sh7760fb_blank,
 350         .fb_check_var = sh7760fb_check_var,
 351         .fb_setcolreg = sh7760_setcolreg,
 352         .fb_set_par = sh7760fb_set_par,
 353 };
 354
 355 static void sh7760fb_free_mem(struct fb_info *info)
 356 {
 357         struct sh7760fb_par *par = info->par;
 358
 359         if (!info->screen_base)
 360                 return;
 361
 362         dma_free_coherent(info->device, info->screen_size,
 363                           info->screen_base, par->fbdma);
 364
 365         par->fbdma = 0;
 366         info->screen_base = NULL;
 367         info->screen_size = 0;
 368 }
 369
 370 /* allocate the framebuffer memory. This memory must be in Area3,
 371  * (dictated by the DMA engine) and contiguous, at a 512 byte boundary.
 372  */
 373 static int sh7760fb_alloc_mem(struct fb_info *info)
 374 {
 375         struct sh7760fb_par *par = info->par;
 376         void *fbmem;
 377         unsigned long vram;
 378         int ret, bpp;
 379
 380         if (info->screen_base)
 381                 return 0;
 382
 383         /* get color info from register value */
 384         ret = sh7760fb_get_color_info(info, par->pd->lddfr, &bpp, NULL);
 385         if (ret) {
 386                 printk(KERN_ERR "colinfo\n");
 387                 return ret;
 388         }
 389
 390         /* min VRAM: xres_min = 16, yres_min = 1, bpp = 1: 2byte -> 1 page
 391            max VRAM: xres_max = 1024, yres_max = 1024, bpp = 16: 2MB */
 392
 393         vram = info->var.xres * info->var.yres;
 394         if (info->var.grayscale) {
 395                 if (bpp == 1)
 396                         vram >>= 3;
 397                 else if (bpp == 2)
 398                         vram >>= 2;
 399                 else if (bpp == 4)
 400                         vram >>= 1;
 401         } else if (bpp > 8)
 402                 vram *= 2;
 403         if ((vram < 1) || (vram > 1024 * 2048)) {
 404                 fb_dbg(info, "too much VRAM required. Check settings\n");
 405                 return -ENODEV;
 406         }
 407
 408         if (vram < PAGE_SIZE)
 409                 vram = PAGE_SIZE;
 410
 411         fbmem = dma_alloc_coherent(info->device, vram, &par->fbdma, GFP_KERNEL);
 412         if (!fbmem)
 413                 return -ENOMEM;
 414
 415         if ((par->fbdma & SH7760FB_DMA_MASK) != SH7760FB_DMA_MASK) {
 416                 dma_free_coherent(info->device, vram, fbmem, par->fbdma);
 417                 dev_err(info->device, "kernel gave me memory at 0x%08lx, which is"
 418                         "unusable for the LCDC\n", (unsigned long)par->fbdma);
 419                 return -ENOMEM;
 420         }
 421
 422         info->screen_base = fbmem;
 423         info->screen_size = vram;
 424         info->fix.smem_start = (unsigned long)info->screen_base;
 425         info->fix.smem_len = info->screen_size;
 426
 427         return 0;
 428 }
 429
 430 static int sh7760fb_probe(struct platform_device *pdev)
 431 {
 432         struct fb_info *info;
 433         struct resource *res;
 434         struct sh7760fb_par *par;
 435         int ret;
 436
 437         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 438         if (unlikely(res == NULL)) {
 439                 dev_err(&pdev->dev, "invalid resource\n");
 440                 return -EINVAL;
 441         }
 442
 443         info = framebuffer_alloc(sizeof(struct sh7760fb_par), &pdev->dev);
 444         if (!info)
 445                 return -ENOMEM;
 446
 447         par = info->par;
 448         par->dev = pdev;
 449
 450         par->pd = pdev->dev.platform_data;
 451         if (!par->pd) {
 452                 dev_dbg(&pdev->dev, "no display setup data!\n");
 453                 ret = -ENODEV;
 454                 goto out_fb;
 455         }
 456
 457         par->ioarea = request_mem_region(res->start,
 458                                          resource_size(res), pdev->name);
 459         if (!par->ioarea) {
 460                 dev_err(&pdev->dev, "mmio area busy\n");
 461                 ret = -EBUSY;
 462                 goto out_fb;
 463         }
 464
 465         par->base = ioremap(res->start, resource_size(res));
 466         if (!par->base) {
 467                 dev_err(&pdev->dev, "cannot remap\n");
 468                 ret = -ENODEV;
 469                 goto out_res;
 470         }
 471
 472         iowrite16(0, par->base + LDINTR);       /* disable vsync irq */
 473         par->irq = platform_get_irq(pdev, 0);
 474         if (par->irq >= 0) {
 475                 ret = request_irq(par->irq, sh7760fb_irq, 0,
 476                                   "sh7760-lcdc", &par->vsync);
 477                 if (ret) {
 478                         dev_err(&pdev->dev, "cannot grab IRQ\n");
 479                         par->irq = -ENXIO;
 480                 } else
 481                         disable_irq_nosync(par->irq);
 482         }
 483
 484         fb_videomode_to_var(&info->var, par->pd->def_mode);
 485
 486         ret = sh7760fb_alloc_mem(info);
 487         if (ret) {
 488                 dev_dbg(info->device, "framebuffer memory allocation failed!\n");
 489                 goto out_unmap;
 490         }
 491
 492         info->pseudo_palette = par->pseudo_palette;
 493
 494         /* fixup color register bitpositions. These are fixed by hardware */
 495         info->var.red.offset = 11;
 496         info->var.red.length = 5;
 497         info->var.red.msb_right = 0;
 498
 499         info->var.green.offset = 5;
 500         info->var.green.length = 6;
 501         info->var.green.msb_right = 0;
 502
 503         info->var.blue.offset = 0;
 504         info->var.blue.length = 5;
 505         info->var.blue.msb_right = 0;
 506
 507         info->var.transp.offset = 0;
 508         info->var.transp.length = 0;
 509         info->var.transp.msb_right = 0;
 510
 511         strcpy(info->fix.id, "sh7760-lcdc");
 512
 513         /* set the DON2 bit now, before cmap allocation, as it will randomize
 514          * palette memory.
 515          */
 516         iowrite16(LDCNTR_DON2, par->base + LDCNTR);
 517         info->fbops = &sh7760fb_ops;
 518
 519         ret = fb_alloc_cmap(&info->cmap, 256, 0);
 520         if (ret) {
 521                 dev_dbg(&pdev->dev, "Unable to allocate cmap memory\n");
 522                 goto out_mem;
 523         }
 524
 525         ret = register_framebuffer(info);
 526         if (ret < 0) {
 527                 dev_dbg(&pdev->dev, "cannot register fb!\n");
 528                 goto out_cmap;
 529         }
 530         platform_set_drvdata(pdev, info);
 531
 532         printk(KERN_INFO "%s: memory at phys 0x%08lx-0x%08lx, size %ld KiB\n",
 533                pdev->name,
 534                (unsigned long)par->fbdma,
 535                (unsigned long)(par->fbdma + info->screen_size - 1),
 536                info->screen_size >> 10);
 537
 538         return 0;
 539
 540 out_cmap:
 541         sh7760fb_blank(FB_BLANK_POWERDOWN, info);
 542         fb_dealloc_cmap(&info->cmap);
 543 out_mem:
 544         sh7760fb_free_mem(info);
 545 out_unmap:
 546         if (par->irq >= 0)
 547                 free_irq(par->irq, &par->vsync);
 548         iounmap(par->base);
 549 out_res:
 550         release_mem_region(res->start, resource_size(res));
 551 out_fb:
 552         framebuffer_release(info);
 553         return ret;
 554 }
 555
 556 static void sh7760fb_remove(struct platform_device *dev)
 557 {
 558         struct fb_info *info = platform_get_drvdata(dev);
 559         struct sh7760fb_par *par = info->par;
 560
 561         sh7760fb_blank(FB_BLANK_POWERDOWN, info);
 562         unregister_framebuffer(info);
 563         fb_dealloc_cmap(&info->cmap);
 564         sh7760fb_free_mem(info);
 565         if (par->irq >= 0)
 566                 free_irq(par->irq, &par->vsync);
 567         iounmap(par->base);
 568         release_mem_region(par->ioarea->start, resource_size(par->ioarea));
 569         framebuffer_release(info);
 570 }
 571
 572 static struct platform_driver sh7760_lcdc_driver = {
 573         .driver = {
 574                    .name = "sh7760-lcdc",
 575                    },
 576         .probe = sh7760fb_probe,
 577         .remove = sh7760fb_remove,
 578 };
 579
 580 module_platform_driver(sh7760_lcdc_driver);
 581
 582 MODULE_AUTHOR("Nobuhiro Iwamatsu, Manuel Lauss");
 583 MODULE_DESCRIPTION("FBdev for SH7760/63 integrated LCD Controller");
 584 MODULE_LICENSE("GPL v2");