drivers/sgi/char/graphics.c

   1 /* $Id: graphics.c,v 1.22 2000/02/18 00:24:43 ralf Exp $
   2  *
   3  * gfx.c: support for SGI's /dev/graphics, /dev/opengl
   4  *
   5  * Author: Miguel de Icaza (miguel@nuclecu.unam.mx)
   6  *         Ralf Baechle (ralf@gnu.org)
   7  *         Ulf Carlsson (ulfc@bun.falkenberg.se)
   8  *
   9  * On IRIX, /dev/graphics is [10, 146]
  10  *          /dev/opengl   is [10, 147]
  11  *
  12  * From a mail with Mark J. Kilgard, /dev/opengl and /dev/graphics are
  13  * the same thing, the use of /dev/graphics seems deprecated though.
  14  *
  15  * The reason that the original SGI programmer had to use only one
  16  * device for all the graphic cards on the system will remain a
  17  * mistery for the rest of our lives.  Why some ioctls take a board
  18  * number and some others not?  Mistery.  Why do they map the hardware
  19  * registers into the user address space with an ioctl instead of
  20  * mmap?  Mistery too.  Why they did not use the standard way of
  21  * making ioctl constants and instead sticked a random constant?
  22  * Mistery too.
  23  *
  24  * We implement those misterious things, and tried not to think about
  25  * the reasons behind them.
  26  */
  27 #include <linux/kernel.h>
  28 #include <linux/fs.h>
  29 #include <linux/init.h>
  30 #include <linux/miscdevice.h>
  31 #include <linux/sched.h>
  32 #include <linux/mm.h>
  33 #include <linux/mman.h>
  34 #include <linux/malloc.h>
  35 #include <linux/module.h>
  36 #include <linux/smp_lock.h>
  37 #include <asm/uaccess.h>
  38 #include "gconsole.h"
  39 #include "graphics.h"
  40 #include "usema.h"
  41 #include <asm/gfx.h>
  42 #include <asm/rrm.h>
  43 #include <asm/page.h>
  44 #include <asm/pgtable.h>
  45 #include <video/newport.h>
  46
  47 #define DEBUG
  48
  49 /* The boards */
  50 extern struct graphics_ops *newport_probe (int, const char **);
  51
  52 static struct graphics_ops cards [MAXCARDS];
  53 static int boards;
  54
  55 #define GRAPHICS_CARD(inode) 0
  56
  57 /*
  58 void enable_gconsole(void) {};
  59 void disable_gconsole(void) {};
  60 */
  61
  62
  63 int
  64 sgi_graphics_open (struct inode *inode, struct file *file)
  65 {
  66         struct newport_regs *nregs =
  67                 (struct newport_regs *) KSEG1ADDR(cards[0].g_regs);
  68
  69         newport_wait();
  70         nregs->set.wrmask = 0xffffffff;
  71         nregs->set.drawmode0 = (NPORT_DMODE0_DRAW | NPORT_DMODE0_BLOCK |
  72                              NPORT_DMODE0_DOSETUP | NPORT_DMODE0_STOPX |
  73                              NPORT_DMODE0_STOPY);
  74         nregs->set.colori = 1;
  75         nregs->set.xystarti = (0 << 16) | 0;
  76         nregs->go.xyendi = (1280 << 16) | 1024;
  77
  78         return 0;
  79 }
  80
  81 int
  82 sgi_graphics_ioctl (struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
  83 {
  84         unsigned int board;
  85         unsigned int devnum = GRAPHICS_CARD (inode->i_rdev);
  86         int i;
  87
  88         if ((cmd >= RRM_BASE) && (cmd <= RRM_CMD_LIMIT))
  89                 return rrm_command (cmd-RRM_BASE, (void *) arg);
  90
  91         switch (cmd){
  92         case GFX_GETNUM_BOARDS:
  93                 return boards;
  94
  95         case GFX_GETBOARD_INFO: {
  96                 struct gfx_getboardinfo_args *bia = (void *) arg;
  97                 void   *dest_buf;
  98                 int    max_len;
  99
 100                 i = verify_area (VERIFY_READ, (void *) arg, sizeof (struct gfx_getboardinfo_args));
 101                 if (i) return i;
 102
 103                 if (__get_user (board,    &bia->board) ||
 104                     __get_user (dest_buf, &bia->buf) ||
 105                     __get_user (max_len,  &bia->len))
 106                         return -EFAULT;
 107
 108                 if (board >= boards)
 109                         return -EINVAL;
 110                 if (max_len < sizeof (struct gfx_getboardinfo_args))
 111                         return -EINVAL;
 112                 if (max_len > cards [board].g_board_info_len)
 113                         max_len = cards [boards].g_board_info_len;
 114                 i = verify_area (VERIFY_WRITE, dest_buf, max_len);
 115                 if (i) return i;
 116                 if (copy_to_user (dest_buf, cards [board].g_board_info, max_len))
 117                         return -EFAULT;
 118                 return max_len;
 119         }
 120
 121         case GFX_ATTACH_BOARD: {
 122                 struct gfx_attach_board_args *att = (void *) arg;
 123                 void *vaddr;
 124                 int  r;
 125
 126                 i = verify_area (VERIFY_READ, (void *)arg, sizeof (struct gfx_attach_board_args));
 127                 if (i) return i;
 128
 129                 if (__get_user (board, &att->board) ||
 130                     __get_user (vaddr, &att->vaddr))
 131                         return -EFAULT;
 132
 133                 /* Ok for now we are assuming /dev/graphicsN -> head N even
 134                  * if the ioctl api suggests that this is not quite the case.
 135                  *
 136                  * Otherwise we fail, we use this assumption in the mmap code
 137                  * below to find our board information.
 138                  */
 139                 if (board != devnum){
 140                         printk ("Parameter board does not match the current board\n");
 141                         return -EINVAL;
 142                 }
 143
 144                 if (board >= boards)
 145                         return -EINVAL;
 146
 147                 /* If it is the first opening it, then make it the board owner */
 148                 if (!cards [board].g_owner)
 149                         cards [board].g_owner = current;
 150
 151                 /*
 152                  * Ok, we now call mmap on this file, which will end up calling
 153                  * sgi_graphics_mmap
 154                  */
 155                 disable_gconsole ();
 156                 down(&current->mm->mmap_sem);
 157                 r = do_mmap (file, (unsigned long)vaddr,
 158                              cards[board].g_regs_size, PROT_READ|PROT_WRITE,
 159                              MAP_FIXED|MAP_PRIVATE, 0);
 160                 up(&current->mm->mmap_sem);
 161                 if (r)
 162                         return r;
 163         }
 164
 165         /* Strange, the real mapping seems to be done at GFX_ATTACH_BOARD,
 166          * GFX_MAPALL is not even used by IRIX X server
 167          */
 168         case GFX_MAPALL:
 169                 return 0;
 170
 171         case GFX_LABEL:
 172                 return 0;
 173
 174                 /* Version check
 175                  * for my IRIX 6.2 X server, this is what the kernel returns
 176                  */
 177         case 1:
 178                 return 3;
 179
 180         /* Xsgi does not use this one, I assume minor is the board being queried */
 181         case GFX_IS_MANAGED:
 182                 if (devnum > boards)
 183                         return -EINVAL;
 184                 return (cards [devnum].g_owner != 0);
 185
 186         default:
 187                 if (cards [devnum].g_ioctl)
 188                         return (*cards [devnum].g_ioctl)(devnum, cmd, arg);
 189
 190         }
 191         return -EINVAL;
 192 }
 193
 194 int
 195 sgi_graphics_close (struct inode *inode, struct file *file)
 196 {
 197         int board = GRAPHICS_CARD (inode->i_rdev);
 198
 199         /* Tell the rendering manager that one client is going away */
 200         lock_kernel();
 201         rrm_close (inode, file);
 202
 203         /* Was this file handle from the board owner?, clear it */
 204         if (current == cards [board].g_owner){
 205                 cards [board].g_owner = 0;
 206                 if (cards [board].g_reset_console)
 207                         (*cards [board].g_reset_console)();
 208                 enable_gconsole ();
 209         }
 210         unlock_kernel();
 211         return 0;
 212 }
 213
 214 /*
 215  * This is the core of the direct rendering engine.
 216  */
 217
 218 unsigned long
 219 sgi_graphics_nopage (struct vm_area_struct *vma, unsigned long address, int
 220                      no_share)
 221 {
 222         pgd_t *pgd; pmd_t *pmd; pte_t *pte;
 223         int board = GRAPHICS_CARD (vma->vm_dentry->d_inode->i_rdev);
 224
 225         unsigned long virt_add, phys_add;
 226
 227 #ifdef DEBUG
 228         printk ("Got a page fault for board %d address=%lx guser=%lx\n", board,
 229                 address, (unsigned long) cards[board].g_user);
 230 #endif
 231
 232         /* Figure out if another process has this mapped, and revoke the mapping
 233          * in that case. */
 234         if (cards[board].g_user && cards[board].g_user != current) {
 235                 /* FIXME: save graphics context here, dump it to rendering
 236                  * node? */
 237
 238                 remove_mapping(cards[board].g_user, vma->vm_start, vma->vm_end);
 239         }
 240
 241         cards [board].g_user = current;
 242
 243         /* Map the physical address of the newport registers into the address
 244          * space of this process */
 245
 246         virt_add = address & PAGE_MASK;
 247         phys_add = cards[board].g_regs + virt_add - vma->vm_start;
 248         remap_page_range(virt_add, phys_add, PAGE_SIZE, vma->vm_page_prot);
 249
 250         pgd = pgd_offset(current->mm, address);
 251         pmd = pmd_offset(pgd, address);
 252         pte = pte_offset(pmd, address);
 253         printk("page: %08lx\n", pte_page(*pte));
 254         return pte_page(*pte);
 255 }
 256
 257 /*
 258  * We convert a GFX ioctl for mapping hardware registers, in a nice sys_mmap
 259  * call, which takes care of everything that must be taken care of.
 260  *
 261  */
 262
 263 static struct vm_operations_struct graphics_mmap = {
 264         nopage: sgi_graphics_nopage,    /* our magic no-page fault handler */
 265 };
 266
 267 int
 268 sgi_graphics_mmap (struct file *file, struct vm_area_struct *vma)
 269 {
 270         uint size;
 271
 272         size = vma->vm_end - vma->vm_start;
 273
 274         /* 1. Set our special graphic virtualizer  */
 275         vma->vm_ops = &graphics_mmap;
 276
 277         /* 2. Set the special tlb permission bits */
 278         vma->vm_page_prot = PAGE_USERIO;
 279
 280         /* final setup */
 281         vma->vm_file = file;
 282         return 0;
 283 }
 284
 285 #if 0
 286 /* Do any post card-detection setup on graphics_ops */
 287 static void
 288 graphics_ops_post_init (int slot)
 289 {
 290         /* There is no owner for the card initially */
 291         cards [slot].g_owner = (struct task_struct *) 0;
 292         cards [slot].g_user  = (struct task_struct *) 0;
 293 }
 294 #endif
 295
 296 struct file_operations sgi_graphics_fops = {
 297         ioctl:          sgi_graphics_ioctl,
 298         mmap:           sgi_graphics_mmap,
 299         open:           sgi_graphics_open,
 300         release:        sgi_graphics_close,
 301 };
 302
 303 /* /dev/graphics */
 304 static struct miscdevice dev_graphics = {
 305         SGI_GRAPHICS_MINOR, "sgi-graphics", &sgi_graphics_fops
 306 };
 307
 308 /* /dev/opengl */
 309 static struct miscdevice dev_opengl = {
 310         SGI_OPENGL_MINOR, "sgi-opengl", &sgi_graphics_fops
 311 };
 312
 313 /* This is called later from the misc-init routine */
 314 void __init gfx_register (void)
 315 {
 316         misc_register (&dev_graphics);
 317         misc_register (&dev_opengl);
 318 }
 319
 320 void __init gfx_init (const char **name)
 321 {
 322 #if 0
 323         struct console_ops *console;
 324         struct graphics_ops *g;
 325 #endif
 326
 327         printk ("GFX INIT: ");
 328         shmiq_init ();
 329         usema_init ();
 330
 331         boards++;
 332
 333 #if 0
 334         if ((g = newport_probe (boards, name)) != 0) {
 335                 cards [boards] = *g;
 336                 graphics_ops_post_init (boards);
 337                 boards++;
 338                 console = 0;
 339         }
 340         /* Add more graphic drivers here */
 341         /* Keep passing console around */
 342 #endif
 343
 344         if (boards > MAXCARDS)
 345                 printk (KERN_WARNING "Too many cards found on the system\n");
 346 }
 347
 348 #ifdef MODULE
 349 int init_module(void) {
 350         static int initiated = 0;
 351
 352         printk("SGI Newport Graphics version %i.%i.%i\n",42,54,69);
 353
 354         if (!initiated++) {
 355                 shmiq_init();
 356                 usema_init();
 357                 printk("Adding first board\n");
 358                 boards++;
 359                 cards[0].g_regs = 0x1f0f0000;
 360                 cards[0].g_regs_size = sizeof (struct newport_regs);
 361         }
 362
 363         printk("Boards: %d\n", boards);
 364
 365         misc_register (&dev_graphics);
 366         misc_register (&dev_opengl);
 367
 368         return 0;
 369 }
 370
 371 void cleanup_module(void) {
 372         printk("Shutting down SGI Newport Graphics\n");
 373
 374         misc_deregister (&dev_graphics);
 375         misc_deregister (&dev_opengl);
 376 }
 377 #endif