rom/graphics/adddisplaydrivera.c

   1 /*
   2     Copyright © 1995-2017, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: AROS-specific function for adding a display driver
   6     Lang: english
   7 */
   8
   9 #include <aros/debug.h>
  10 #include <graphics/driver.h>
  11 #include <hidd/compositor.h>
  12 #include <oop/oop.h>
  13
  14 #include <proto/utility.h>
  15
  16 #include "graphics_intern.h"
  17 #include "compositor_driver.h"
  18 #include "dispinfo.h"
  19
  20 #define CL(x) ((OOP_Class *)x)
  21 #define IS_CLASS(x, n) (CL(x)->ClassNode.ln_Name && (!strcmp(CL(x)->ClassNode.ln_Name, n)))
  22
  23 /*****************************************************************************
  24
  25     NAME */
  26 #include <proto/graphics.h>
  27
  28         AROS_LH3(ULONG, AddDisplayDriverA,
  29
  30 /*  SYNOPSIS */
  31         AROS_LHA(APTR, gfxclass, A0),
  32         AROS_LHA(const struct TagItem *, attrs, A1),
  33         AROS_LHA(const struct TagItem *, tags, A2),
  34
  35 /*  LOCATION */
  36         struct GfxBase *, GfxBase, 107, Graphics)
  37
  38 /*  FUNCTION
  39         Add a display driver to the system.
  40
  41     INPUTS
  42         gfxhidd - A pointer to an OOP class of the display driver
  43         attrs   - Additional attributes to supply to the driver class during
  44                   object creation
  45         tags    - An optional TagList describing how graphics.library should
  46             handle the driver. Valid tags are:
  47
  48             DDRV_BootMode     - A boolean value telling that a boot mode
  49                                 driver is being added. Boot mode drivers
  50                                 will automatically shut down on next
  51                                 AddDisplayDriverA() call, unless
  52                                 DDRV_KeepBootMode = TRUE is specified.
  53                                 Defaults to FALSE.
  54             DDRV_MonitorID    - Starting monitor ID to assign to the driver.
  55                                 Use it with care. An attempt to add already
  56                                 existing ID will fail with a DD_ID_EXISTS
  57                                 code. By default the next available ID will
  58                                 be picked up automatically.
  59             DDRV_ReserveIDs   - The number of subsequent monitor IDs to
  60                                 reserve. Reserved IDs can be reused only
  61                                 with DDRV_MonitorID tag. This tag is
  62                                 provided as an aid to support possible
  63                                 removable display devices. Defaults to 1.
  64             DDRV_KeepBootMode - Do not shut down boot mode drivers. Use this
  65                                 tag if you are 100% sure that your driver
  66                                 won't conflict with boot mode driver (like
  67                                 VGA or VESA) and won't attempt to take over
  68                                 its hardware. Defaults to FALSE.
  69             DDRV_ResultID     - A pointer to a ULONG location where the ID
  70                                 assigned to your driver will be placed.
  71                                 Useful if you reserve some ID for future use.
  72                                 Note that the returned ID will be the one
  73                                 just assigned to your driver instance.
  74                                 Increment it yourself in order to obtain
  75                                 other reserved IDs.
  76             DDRV_IDMask       - A mask for separating the monitor ID from the
  77                                 HIDD-specific part. This mask specifies what
  78                                 mode ID bits are the monitor ID and what bits
  79                                 actually specify the mode. The default value
  80                                 is 0xFFFF0000.
  81
  82                                 Using the mask you can split your monitor ID
  83                                 into 'sub-Ids'. Example:
  84
  85                                 Supplied tags: DDRV_IDMask, 0xFFFFFF00,
  86                                                DDRV_ResultID, &myid
  87
  88                                 After a successful call, myid will contain the
  89                                 base ID assigned by graphics.library to your
  90                                 driver, let's say 0x00140000. However, since
  91                                 you specified a longer mask, you leave only
  92                                 one byte for mode designation, and reserve
  93                                 the whole range of IDs from 0x001400xx to
  94                                 0x0014FFxx for different instances of your
  95                                 driver. They can now be used by specifying
  96                                 DDRV_MonitorID with corresponding value.
  97
  98                                 Note that for this feature to work correctly,
  99                                 you also need to override ID processing in
 100                                 your driver class. Default methods provided
 101                                 by the hidd.graphics.graphics base class
 102                                 suppose that the whole lower word of the mode
 103                                 ID specifies the display mode.
 104
 105                                 It is generally not allowed to specify
 106                                 shorter masks than 0xFFFF0000. The only
 107                                 driver which can do this is the Amiga(TM)
 108                                 chipset driver, which needs to occupy the
 109                                 reserved range of IDs from 0x0000xxxx to
 110                                 0x000Axxxx. In any other case, supplying a
 111                                 short mask will cause undefined behavior.
 112
 113                                 Since DDRV_ReserveIDs provides a simpler way
 114                                 to reserve IDs for your driver (without the
 115                                 need to override mode ID processing), this
 116                                 option can be considered experimental and
 117                                 even private. In fact the primary reason for
 118                                 it to exist is to provide support for
 119                                 Amiga(tm) chipset driver.
 120
 121     RESULT
 122         error - One of following codes:
 123
 124             DD_OK           - Operation completed OK.
 125             DD_NO_MEM       - There is not enough memory to set up internal
 126                               data.
 127             DD_ID_EXISTS    - Attempt to assign monitor IDs that are already
 128                               used.
 129             DD_IN_USE       - One of boot-mode drivers is in use and cannot
 130                               be shut down.
 131             DD_DRIVER_ERROR - Failure to create driver object.
 132
 133     NOTES
 134         This function is AROS-specific.
 135
 136     EXAMPLE
 137
 138     BUGS
 139
 140     SEE ALSO
 141
 142     INTERNALS
 143
 144 *****************************************************************************/
 145 {
 146     AROS_LIBFUNC_INIT
 147
 148     struct TagItem *tag, *tstate = (struct TagItem *)tags;
 149     struct monitor_driverdata *mdd;
 150     ULONG FirstID = INVALID_ID;
 151     ULONG NextID;
 152     ULONG NumIDs = 1;
 153     ULONG IDMask = AROS_MONITOR_ID_MASK;
 154     BOOL keep_boot = FALSE;
 155     UWORD flags = 0;
 156     ULONG *ResultID = NULL;
 157     ULONG ret = DD_OK;
 158
 159     EnterFunc(bug("AddDisplayDriverA(0x%p) <%s>\n", gfxclass, CL(gfxclass)->ClassNode.ln_Name));
 160
 161     /*
 162      * MAGIC: Detect composition HIDD here.
 163      * This allows to hotplug it, and even (potentially) replace.
 164      */
 165     if (IS_CLASS(gfxclass, CLID_Hidd_Compositor))
 166     {
 167         ObtainSemaphore(&CDD(GfxBase)->displaydb_sem);
 168         ret = compositor_Install(gfxclass, GfxBase);
 169         ReleaseSemaphore(&CDD(GfxBase)->displaydb_sem);
 170
 171         return ret;
 172     }
 173
 174     /* First parse parameters */
 175     while ((tag = NextTagItem(&tstate)))
 176     {
 177         switch (tag->ti_Tag)
 178         {
 179         case DDRV_MonitorID:
 180             FirstID = tag->ti_Data;
 181             break;
 182
 183         case DDRV_ReserveIDs:
 184             NumIDs = tag->ti_Data;
 185             break;
 186
 187         case DDRV_IDMask:
 188             IDMask = tag->ti_Data;
 189             break;
 190
 191         case DDRV_KeepBootMode:
 192             keep_boot = tag->ti_Data;
 193             break;
 194
 195         case DDRV_BootMode:
 196             flags = tag->ti_Data ? DF_BootMode : 0;
 197             break;
 198
 199         case DDRV_ResultID:
 200             ResultID = (ULONG *)tag->ti_Data;
 201             break;
 202         }
 203     }
 204
 205     /* We lock for the entire function because we want to be sure that
 206        IDs will remain free during driver_Setup() */
 207     ObtainSemaphore(&CDD(GfxBase)->displaydb_sem);
 208
 209     /* Default value for monitor ID */
 210     if (FirstID == INVALID_ID)
 211     {
 212         /*
 213          * The logic here prevents ID clash if specified mask is wider than previous one.
 214          * Example situation:
 215          * 1. Add driver with mask = 0xFFFF0000. FirstID = 0x00100000, NextID = 0x00110000.
 216          * 2. Add driver with mask = 0xF0000000. FirstID = 0x00110000, AND with this mask
 217          *    would give monitor ID = 0.
 218          * In order to prevent this, we make one more increment, so that in (2) FirstID becomes
 219          * 0x10000000. The increment mechanism itself is explained below.
 220          * Note that the adjustments happens only for automatic ID assignment. In case of manual
 221          * one (DDRV_MonitorID specified) we suggest our caller knows what he does.
 222          */
 223         FirstID = CDD(GfxBase)->last_id & IDMask;
 224
 225         if (FirstID < CDD(GfxBase)->last_id)
 226             FirstID += (~(IDMask & AROS_MONITOR_ID_MASK) + 1);
 227     }
 228
 229     /*
 230      * Calculate next free ID.
 231      * Mechanism of increment calculation: we invert the mask and add 1 to it.
 232      * This way for example 0xFFFF0000 becomes 0x00010000.
 233      * Before doing this we make sure that mask used in this equation is not
 234      * longer than 0xFFFF0000, for proper ID counting.
 235      */
 236     NextID = FirstID + NumIDs * (~(IDMask & AROS_MONITOR_ID_MASK) + 1);
 237     D(bug("[AddDisplayDriverA] First ID 0x%08X, next ID 0x%08X\n", FirstID, NextID));
 238
 239     /* First check if the operation can actually be performed */
 240     for (mdd = CDD(GfxBase)->monitors; mdd; mdd = mdd->next)
 241     {
 242         /* Check if requested IDs are already allocated */
 243         if ((mdd->id >= FirstID && mdd->id < NextID))
 244         {
 245             ret = DD_ID_EXISTS;
 246             break;
 247         }
 248
 249         /*
 250          * Now check if boot mode drivers can really be unloaded.
 251          * Display drivers can start playing with their hardware during
 252          * object creation, so we need to check it before instantiating
 253          * the given class.
 254          */
 255         if (!keep_boot)
 256         {
 257             /* The driver can be unloaded if it has nothing on display */
 258             if ((mdd->flags & DF_BootMode) && (mdd->display))
 259             {
 260                 ret = DD_IN_USE;
 261                 break;
 262             }
 263         }
 264     }
 265
 266     /*
 267      * Now, if everything is okay, we are ready to instantiate the driver.
 268      * A well-behaved driver must touch the hardware only in object, not
 269      * in class. This makes this function much safer. If we can't exit boot mode,
 270      * the driver will not be instantiated and hardware state will not be clobbered.
 271      */
 272     if (ret == DD_OK)
 273     {
 274         OOP_Object *gfxhidd = HW_AddDriver(PrivGBase(GfxBase)->GfxRoot, gfxclass, (struct TagItem *)attrs);
 275
 276         if (gfxhidd)
 277         {
 278             D(bug("[AddDisplayDriverA] Installing driver\n"));
 279
 280             /* Attach system structures to the driver */
 281             mdd = driver_Setup(gfxhidd, GfxBase);
 282             D(bug("[AddDisplayDriverA] monitor_driverdata 0x%p\n", mdd));
 283
 284             if (mdd)
 285             {
 286                 struct monitor_driverdata *last, *old;
 287
 288                 mdd->id    =  FirstID;
 289                 mdd->mask  =  IDMask;
 290                 mdd->flags |= flags;
 291
 292                 if (CDD(GfxBase)->DriverNotify)
 293                 {
 294                     /* Use mdd->gfxhidd here because it can be substituted by fakegfx object */
 295                     mdd->userdata = CDD(GfxBase)->DriverNotify(mdd, TRUE, CDD(GfxBase)->notify_data);
 296                 }
 297
 298                 /* Remove boot mode drivers */
 299                 if (!keep_boot)
 300                 {
 301                     D(bug("[AddDisplayDriverA] Shutting down boot mode drivers\n"));
 302                     for (last = (struct monitor_driverdata *)CDD(GfxBase);; last = last->next)
 303                     {
 304                         D(bug("[AddDisplayDriverA] Current 0x%p, next 0x%p\n", last, last->next));
 305
 306                         while (last->next && (last->next->flags & DF_BootMode))
 307                         {
 308                             old = last->next;
 309                             D(bug("[AddDisplayDriverA] Shutting down driver 0x%p (ID 0x%08lX, next 0x%p)\n", old, old->id, old->next));
 310
 311                             last->next = old->next;
 312                             driver_Expunge(old, GfxBase);
 313                             D(bug("[AddDisplayDriverA] Shutdown OK, next 0x%p\n", last->next));
 314                         }
 315
 316                         /*
 317                          * We check this condition here explicitly because last->next is modified inside loop body.
 318                          * If we check it in for() statement, last = last->next will be executed BEFORE the check,
 319                          * and NULL pointer may be hit.
 320                          */
 321                         if (!last->next)
 322                             break;
 323                     }
 324                 }
 325
 326                 /* Insert the driverdata into chain, sorted by ID */
 327                 D(bug("[AddDisplayDriverA] Inserting driver 0x%p, ID 0x%08lX\n", mdd, mdd->id));
 328                 for (last = (struct monitor_driverdata *)CDD(GfxBase); last->next; last = last->next)
 329                 {
 330                     D(bug("[AddDisplayDriverA] Current 0x%p, next 0x%p, ID 0x%08lX\n", last, last->next, last->next->id));
 331                     if (mdd->id < last->next->id)
 332                         break;
 333                 }
 334
 335                 D(bug("[AddDisplayDriverA] Inserting after 0x%p\n", last));
 336                 mdd->next = last->next;
 337                 last->next = mdd;
 338
 339                 /* Remember next available ID */
 340                 if (NextID > CDD(GfxBase)->last_id)
 341                     CDD(GfxBase)->last_id = NextID;
 342
 343                 /* Return the assigned ID if the caller asked to do so */
 344                 if (ResultID)
 345                     *ResultID = FirstID;
 346             }
 347             else /* if (mdd) */
 348             {
 349                 OOP_DisposeObject(gfxhidd);
 350                 ret = DD_NO_MEM;
 351             }
 352         }
 353         else /* if (gfxhidd) */
 354         {
 355             ret = DD_DRIVER_ERROR;
 356         }
 357     } /* if (ret == DD_OK) */
 358
 359     ReleaseSemaphore(&CDD(GfxBase)->displaydb_sem);
 360
 361     /* Set the first non-boot non-planar driver as default */
 362     if ((ret == DD_OK) && (!GfxBase->default_monitor) && (!(mdd->flags & DF_BootMode)))
 363     {
 364         /*
 365          * Amiga(tm) chipset driver does not become a default.
 366          * This is done because RTG modes (if any) are commonly preferred
 367          * over it.
 368          * TODO: in future some prefs program could be implemented. It would
 369          * allow the user to describe the physical placement of several displays
 370          * in his environment, and explicitly set the preferred display.
 371          */
 372         if (!IS_CLASS(gfxclass, "hidd.gfx.amigavideo"))
 373         {
 374             /*
 375              * graphics.library uses struct MonitorSpec pointers for historical reasons,
 376              * so we satisfy it.
 377              * Here we just get the first available sync object from the driver and
 378              * set default_monitor fo its MonitorSpec. This allows BestModeIDA() to
 379              * obtain preferred monitor back from this MonitorSpec (by asking the associated
 380              * sync object about its parent driver).
 381              *
 382              * TODO:
 383              * Originally display drivers in AmigaOS had a concept of "preferred mode ID".
 384              * Every driver supplied own hardcoded ID which can be retrieved by GetDisplayInfoData()
 385              * in MonitorInfo->PreferredModeID. Currently AROS does not implement this concept.
 386              * However this sync could be a preferred mode's sync.
 387              * It needs to be researched what exactly this mode ID is. Implementing this concept would
 388              * improve AmigaOS(tm) compatibility.
 389              */
 390             OOP_Object *sync = HIDD_Gfx_GetSync(mdd->gfxhidd_orig, 0);
 391
 392             OOP_GetAttr(sync, aHidd_Sync_MonitorSpec, (IPTR *)&GfxBase->default_monitor);
 393         }
 394     }
 395
 396     D(bug("[AddDisplayDriverA] Returning %u\n", ret));
 397     return ret;
 398
 399     AROS_LIBFUNC_EXIT
 400 } /* LateGfxInit */