KernelLand/Modules/USB/EHCI/ehci.c

   1 /*
   2  * Acess2 EHCI Driver
   3  * - By John Hodge (thePowersGang)
   4  *
   5  * ehci.c
   6  * - Driver Core
   7  */
   8 #define DEBUG   1
   9 #define VERSION VER2(0,1)
  10 #include <acess.h>
  11 #include <modules.h>
  12 #include <usb_host.h>
  13 #include "ehci.h"
  14 #include <drv_pci.h>
  15 #include <limits.h>
  16 #include <events.h>
  17 #include <timers.h>
  18
  19 // === CONSTANTS ===
  20 #define EHCI_MAX_CONTROLLERS    4
  21 #define EHCI_THREADEVENT_IOC    THREAD_EVENT_USER1
  22 #define EHCI_THREADEVENT_PORTSC THREAD_EVENT_USER2
  23
  24 // === PROTOTYPES ===
  25  int    EHCI_Initialise(char **Arguments);
  26  int    EHCI_Cleanup(void);
  27  int    EHCI_InitController(tPAddr BaseAddress, Uint8 InterruptNum);
  28 void    EHCI_InterruptHandler(int IRQ, void *Ptr);
  29 // -- API ---
  30 void    *EHCI_InitInterrupt(void *Ptr, int Endpoint, int bInput, int Period, tUSBHostCb Cb, void *CbData, void *Buf, size_t Length);
  31 void    *EHCI_InitIsoch  (void *Ptr, int Endpoint, size_t MaxPacketSize);
  32 void    *EHCI_InitControl(void *Ptr, int Endpoint, size_t MaxPacketSize);
  33 void    *EHCI_InitBulk   (void *Ptr, int Endpoint, size_t MaxPacketSize);
  34 void    EHCI_RemEndpoint(void *Ptr, void *Handle);
  35 void    *EHCI_SendControl(void *Ptr, void *Dest, tUSBHostCb Cb, void *CbData,
  36         int isOutbound,
  37         const void *SetupData, size_t SetupLength,
  38         const void *OutData, size_t OutLength,
  39         void *InData, size_t InLength
  40         );
  41 void    *EHCI_SendBulk(void *Ptr, void *Dest, tUSBHostCb Cb, void *CbData, int Dir, void *Data, size_t Length);
  42 void    EHCI_FreeOp(void *Ptr, void *Handle);
  43 Uint32  EHCI_int_RootHub_FeatToMask(int Feat);
  44 void    EHCI_RootHub_SetPortFeature(void *Ptr, int Port, int Feat);
  45 void    EHCI_RootHub_ClearPortFeature(void *Ptr, int Port, int Feat);
  46  int    EHCI_RootHub_GetPortStatus(void *Ptr, int Port, int Flag);
  47 // --- Internals ---
  48 tEHCI_qTD       *EHCI_int_AllocateTD(tEHCI_Controller *Cont, int PID, void *Data, size_t Length, tUSBHostCb Cb, void *CbData);
  49 void    EHCI_int_DeallocateTD(tEHCI_Controller *Cont, tEHCI_qTD *TD);
  50 void    EHCI_int_AppendTD(tEHCI_Controller *Cont, tEHCI_QH *QH, tEHCI_qTD *TD);
  51 tEHCI_QH        *EHCI_int_AllocateQH(tEHCI_Controller *Cont, int Endpoint, size_t MaxPacketSize);
  52 void    EHCI_int_DeallocateQH(tEHCI_Controller *Cont, tEHCI_QH *QH);
  53 void    EHCI_int_InterruptThread(void *ControllerPtr);
  54
  55 // === GLOBALS ===
  56 MODULE_DEFINE(0, VERSION, USB_EHCI, EHCI_Initialise, NULL, "USB_Core", NULL);
  57 tEHCI_Controller        gaEHCI_Controllers[EHCI_MAX_CONTROLLERS];
  58 tUSBHostDef     gEHCI_HostDef = {
  59         .InitInterrupt = EHCI_InitInterrupt,
  60         .InitIsoch     = EHCI_InitIsoch,
  61         .InitControl   = EHCI_InitControl,
  62         .InitBulk      = EHCI_InitBulk,
  63         .RemEndpoint   = EHCI_RemEndpoint,
  64         .SendIsoch   = NULL,
  65         .SendControl = EHCI_SendControl,
  66         .SendBulk    = EHCI_SendBulk,
  67         .FreeOp      = EHCI_FreeOp,
  68
  69         .CheckPorts = NULL,     // No need
  70         .SetPortFeature   = EHCI_RootHub_SetPortFeature,
  71         .ClearPortFeature = EHCI_RootHub_ClearPortFeature,
  72         .GetPortStatus    = EHCI_RootHub_GetPortStatus,
  73         };
  74
  75 // === CODE ===
  76 int EHCI_Initialise(char **Arguments)
  77 {
  78         for( int id = -1; (id = PCI_GetDeviceByClass(0x0C0320, 0xFFFFFF, id)) >= 0;  )
  79         {
  80                 Uint32  addr = PCI_GetBAR(id, 0);
  81                 if( addr == 0 ) {
  82                         // Oops, PCI BIOS emulation time
  83                 }
  84                 Uint8   irq = PCI_GetIRQ(id);
  85                 if( irq == 0 ) {
  86                         // TODO: The same
  87                 }
  88
  89                 Log_Log("ECHI", "Controller at PCI %i 0x%x IRQ 0x%x",
  90                         id, addr, irq);
  91
  92                 if( EHCI_InitController(addr, irq) )
  93                 {
  94                         // TODO: Detect other forms of failure than "out of slots"
  95                         break ;
  96                 }
  97
  98                 // TODO: Register with the USB stack
  99         }
 100         return 0;
 101 }
 102
 103 int EHCI_Cleanup(void)
 104 {
 105         return 0;
 106 }
 107
 108 // --- Driver Init ---
 109 int EHCI_InitController(tPAddr BaseAddress, Uint8 InterruptNum)
 110 {
 111         tEHCI_Controller        *cont = NULL;
 112
 113         for( int i = 0; i < EHCI_MAX_CONTROLLERS; i ++ )
 114         {
 115                 if( gaEHCI_Controllers[i].PhysBase == 0 ) {
 116                         cont = &gaEHCI_Controllers[i];
 117                         cont->PhysBase = BaseAddress;
 118                         break;
 119                 }
 120         }
 121         if(!cont) {
 122                 Log_Notice("EHCI", "Too many controllers (EHCI_MAX_CONTROLLERS=%i)",
 123                         EHCI_MAX_CONTROLLERS);
 124                 return 1;
 125         }
 126
 127         // - Nuke a couple of fields so error handling code doesn't derp
 128         cont->CapRegs = NULL;
 129         cont->PeriodicQueue = NULL;
 130         cont->TDPool = NULL;
 131
 132         // -- Build up structure --
 133         cont->CapRegs = (void*)MM_MapHWPages(BaseAddress, 1);
 134         if( !cont->CapRegs ) {
 135                 Log_Warning("EHCI", "Can't map 1 page at %P into kernel space", BaseAddress);
 136                 goto _error;
 137         }
 138         // TODO: Error check
 139         if( (cont->CapRegs->CapLength & 3) ) {
 140                 Log_Warning("EHCI", "Controller at %P non-aligned op regs", BaseAddress);
 141                 goto _error;
 142         }
 143         cont->OpRegs = (void*)( (Uint32*)cont->CapRegs + cont->CapRegs->CapLength / 4 );
 144         // - Allocate periodic queue
 145         tPAddr  unused;
 146         cont->PeriodicQueue = (void*)MM_AllocDMA(1, 32, &unused);
 147         if( !cont->PeriodicQueue ) {
 148                 Log_Warning("ECHI", "Can't allocate 1 32-bit page for periodic queue");
 149                 goto _error;
 150         }
 151         for( int i = 0; i < 1024; i ++ )
 152                 cont->PeriodicQueue[i] = 1;
 153         // TODO: Error check
 154         //  > Populate queue
 155
 156         // - Allocate TD pool
 157         cont->TDPool = (void*)MM_AllocDMA(1, 32, &unused);
 158         if( !cont->TDPool ) {
 159                 Log_Warning("ECHI", "Can't allocate 1 32-bit page for qTD pool");
 160                 goto _error;
 161         }
 162         for( int i = 0; i < TD_POOL_SIZE; i ++ ) {
 163                 cont->TDPool[i].Token = 3 << 8;
 164         }
 165
 166         // Get port count
 167         cont->nPorts = cont->CapRegs->HCSParams & 0xF;
 168
 169         // -- Bind IRQ --
 170         IRQ_AddHandler(InterruptNum, EHCI_InterruptHandler, cont);
 171         cont->InterruptThread = Proc_SpawnWorker(EHCI_int_InterruptThread, cont);
 172         if( !cont->InterruptThread ) {
 173                 Log_Warning("EHCI", "Can't spawn interrupt worker thread");
 174                 goto _error;
 175         }
 176         LOG("cont->InterruptThread = %p", cont->InterruptThread);
 177
 178         // -- Initialisation procedure (from ehci-r10) --
 179         // - Reset controller
 180         cont->OpRegs->USBCmd = USBCMD_HCReset;
 181         // - Set CTRLDSSEGMENT (TODO: 64-bit support)
 182         // - Set USBINTR
 183         cont->OpRegs->USBIntr = USBINTR_IOC|USBINTR_PortChange|USBINTR_FrameRollover;
 184         // - Set PERIODICLIST BASE
 185         cont->OpRegs->PeridocListBase = MM_GetPhysAddr( cont->PeriodicQueue );
 186         // - Enable controller
 187         cont->OpRegs->USBCmd = (0x40 << 16) | USBCMD_PeriodicEnable | USBCMD_Run;
 188         // - Route all ports
 189         cont->OpRegs->ConfigFlag = 1;
 190
 191         cont->DeadTD = EHCI_int_AllocateTD(cont, 0, NULL, 0, NULL, NULL);
 192         cont->DeadTD->Link = 1;
 193         cont->DeadTD->Link2 = 1;
 194         cont->DeadTD->Token = 0;
 195
 196         // -- Register with USB Core --
 197         cont->RootHub = USB_RegisterHost(&gEHCI_HostDef, cont, cont->nPorts);
 198
 199         return 0;
 200 _error:
 201         cont->PhysBase = 0;
 202         if( cont->CapRegs )
 203                 MM_Deallocate( (tVAddr)cont->CapRegs );
 204         if( cont->PeriodicQueue )
 205                 MM_Deallocate( (tVAddr)cont->PeriodicQueue );
 206         if( cont->TDPool )
 207                 MM_Deallocate( (tVAddr)cont->TDPool );
 208         return 2;
 209 }
 210
 211 void EHCI_InterruptHandler(int IRQ, void *Ptr)
 212 {
 213         tEHCI_Controller *Cont = Ptr;
 214         Uint32  sts = Cont->OpRegs->USBSts;
 215
 216         // Clear interrupts
 217         Cont->OpRegs->USBSts = sts;
 218
 219         if( sts & 0xFFFF0FC0 ) {
 220                 LOG("Oops, reserved bits set (%08x), funny hardware?", sts);
 221                 sts &= ~0xFFFF0FFC0;
 222         }
 223
 224         // Unmask read-only bits
 225         sts &= ~(0xF000);
 226
 227         if( sts & USBINTR_IOC ) {
 228                 // IOC
 229                 Threads_PostEvent(Cont->InterruptThread, EHCI_THREADEVENT_IOC);
 230                 sts &= ~USBINTR_IOC;
 231         }
 232
 233         if( sts & USBINTR_PortChange ) {
 234                 // Port change, determine what port and poke helper thread
 235                 LOG("Port status change");
 236                 Threads_PostEvent(Cont->InterruptThread, EHCI_THREADEVENT_PORTSC);
 237                 sts &= ~USBINTR_PortChange;
 238         }
 239
 240         if( sts & USBINTR_FrameRollover ) {
 241                 // Frame rollover, used to aid timing (trigger per-second operations)
 242                 LOG("Frame rollover");
 243                 sts &= ~USBINTR_FrameRollover;
 244         }
 245
 246         if( sts ) {
 247                 // Unhandled interupt bits
 248                 // TODO: Warn
 249                 LOG("WARN - Bitmask %x unhandled", sts);
 250         }
 251
 252
 253 }
 254
 255 // --------------------------------------------------------------------
 256 // USB API
 257 // --------------------------------------------------------------------
 258 void *EHCI_InitInterrupt(void *Ptr, int Endpoint, int bOutbound, int Period,
 259         tUSBHostCb Cb, void *CbData, void *Buf, size_t Length)
 260 {
 261         tEHCI_Controller        *Cont = Ptr;
 262          int    pow2period, period_pow;
 263
 264         if( Endpoint >= 256*16 )
 265                 return NULL;
 266         if( Period <= 0 )
 267                 return NULL;
 268         if( Period > 256 )
 269                 Period = 256;
 270
 271         LOG("Endpoint=%x, bOutbound=%i, Period=%i, Length=%i", Endpoint, bOutbound, Period, Length);
 272
 273         // Round the period to the closest power of two
 274         pow2period = 1;
 275         period_pow = 0;
 276         // - Find the first power above the period
 277         while( pow2period < Period )
 278         {
 279                 pow2period *= 2;
 280                 period_pow ++;
 281         }
 282         // - Check which is closest
 283         if( Period - pow2period / 2 > pow2period - Period )
 284                 Period = pow2period;
 285         else {
 286                 Period = pow2period/2;
 287                 period_pow --;
 288         }
 289
 290         // Allocate a QH
 291         tEHCI_QH *qh = EHCI_int_AllocateQH(Cont, Endpoint, Length);
 292         qh->Impl.IntPeriodPow = period_pow;
 293
 294         Mutex_Acquire(&Cont->PeriodicListLock);
 295
 296         // Choose an interrupt slot to use
 297         int minslot = 0, minslot_load = INT_MAX;
 298         for( int slot = 0; slot < Period; slot ++ )
 299         {
 300                  int    load = 0;
 301                 for( int i = 0; i < PERIODIC_SIZE; i += Period )
 302                         load += Cont->InterruptLoad[i+slot];
 303                 if( load == 0 ) break;
 304                 if( load < minslot_load ) {
 305                         minslot = slot;
 306                         minslot_load = load;
 307                 }
 308         }
 309         // Increase loading on the selected slot
 310         for( int i = minslot; i < PERIODIC_SIZE; i += Period )
 311                 Cont->InterruptLoad[i] += Length;
 312         qh->Impl.IntOfs = minslot;
 313
 314         // Allocate TD for the data
 315         tEHCI_qTD *td = EHCI_int_AllocateTD(Cont, (bOutbound ? PID_OUT : PID_IN), Buf, Length, Cb, CbData);
 316         EHCI_int_AppendTD(Cont, qh, td);
 317
 318         // Insert into the periodic list
 319         for( int i = 0; i < PERIODIC_SIZE; i += Period )
 320         {
 321                 // Walk list until
 322                 // - the end is reached
 323                 // - this QH is found
 324                 // - A QH with a lower period is encountered
 325                 tEHCI_QH        *pqh = NULL;
 326                 tEHCI_QH        *nqh;
 327                 for( nqh = Cont->PeriodicQueueV[i]; nqh; pqh = nqh, nqh = nqh->Impl.Next )
 328                 {
 329                         if( nqh == qh )
 330                                 break;
 331                         if( nqh->Impl.IntPeriodPow < period_pow )
 332                                 break;
 333                 }
 334
 335                 // Somehow, we've already been added to this queue.
 336                 if( nqh && nqh == qh )
 337                         continue ;
 338
 339                 if( qh->Impl.Next && qh->Impl.Next != nqh ) {
 340                         Log_Warning("EHCI", "Suspected bookkeeping error on %p - int list %i+%i overlap",
 341                                 Cont, period_pow, minslot);
 342                         break;
 343                 }
 344
 345                 if( nqh ) {
 346                         qh->Impl.Next = nqh;
 347                         qh->HLink = MM_GetPhysAddr(nqh) | 2;
 348                 }
 349                 else {
 350                         qh->Impl.Next = NULL;
 351                         qh->HLink = 2|1;        // QH, Terminate
 352                 }
 353
 354                 if( pqh ) {
 355                         pqh->Impl.Next = qh;
 356                         pqh->HLink = MM_GetPhysAddr(qh) | 2;
 357                 }
 358                 else {
 359                         Cont->PeriodicQueueV[i] = qh;
 360                         Cont->PeriodicQueue[i] = MM_GetPhysAddr(qh) | 2;
 361                 }
 362         }
 363         Mutex_Release(&Cont->PeriodicListLock);
 364
 365         return qh;
 366 }
 367
 368 void *EHCI_InitIsoch(void *Ptr, int Endpoint, size_t MaxPacketSize)
 369 {
 370         return (void*)(tVAddr)(Endpoint + 1);
 371 }
 372 void *EHCI_InitControl(void *Ptr, int Endpoint, size_t MaxPacketSize)
 373 {
 374         tEHCI_Controller *Cont = Ptr;
 375
 376         // Allocate a QH
 377         tEHCI_QH *qh = EHCI_int_AllocateQH(Cont, Endpoint, MaxPacketSize);
 378         qh->CurrentTD = MM_GetPhysAddr(Cont->DeadTD);
 379
 380         // Append to async list
 381         if( Cont->LastAsyncHead ) {
 382                 Cont->LastAsyncHead->HLink = MM_GetPhysAddr(qh)|2;
 383                 Cont->LastAsyncHead->Impl.Next = qh;
 384                 LOG("- Placed after %p", Cont->LastAsyncHead);
 385         }
 386         else {
 387                 Cont->OpRegs->AsyncListAddr = MM_GetPhysAddr(qh)|2;
 388         }
 389         qh->HLink = Cont->OpRegs->AsyncListAddr;
 390         Cont->OpRegs->USBCmd |= USBCMD_AsyncEnable;
 391         Cont->LastAsyncHead = qh;
 392
 393         LOG("Created %p for %p Ep 0x%x - %i bytes MPS", qh, Ptr, Endpoint, MaxPacketSize);
 394
 395         return qh;
 396 }
 397 void *EHCI_InitBulk(void *Ptr, int Endpoint, size_t MaxPacketSize)
 398 {
 399         return EHCI_InitControl(Ptr, Endpoint, MaxPacketSize);
 400 }
 401 void EHCI_RemEndpoint(void *Ptr, void *Handle)
 402 {
 403         if( Handle == NULL )
 404                 return ;
 405         else if( (tVAddr)Handle <= 256*16 )
 406                 return ;        // Isoch
 407         else {
 408                 tEHCI_QH        *qh = Ptr;
 409
 410                 // Remove QH from list
 411                 // - If it's a polling endpoint, need to remove from all periodic lists
 412                 if( qh->Impl.IntPeriodPow != 0xFF) {
 413                         // Poll
 414                 }
 415                 else {
 416                         // GP
 417                 }
 418
 419                 // Deallocate QH
 420                 EHCI_int_DeallocateQH(Ptr, Handle);
 421         }
 422 }
 423
 424 void *EHCI_SendControl(void *Ptr, void *Dest, tUSBHostCb Cb, void *CbData,
 425         int isOutbound,
 426         const void *SetupData, size_t SetupLength,
 427         const void *OutData, size_t OutLength,
 428         void *InData, size_t InLength
 429         )
 430 {
 431         tEHCI_Controller *Cont = Ptr;
 432         tEHCI_qTD       *td_setup, *td_data, *td_status;
 433
 434         // Sanity checks
 435         if( (tVAddr)Dest <= 256*16 )
 436                 return NULL;
 437
 438         LOG("Dest=%p, isOutbound=%i, Lengths(Setup:%i,Out:%i,In:%i)", Dest, isOutbound, SetupLength, OutLength, InLength);
 439
 440         // Check size of SETUP and status
 441
 442         // Allocate TDs
 443         td_setup = EHCI_int_AllocateTD(Cont, PID_SETUP, (void*)SetupData, SetupLength, NULL, NULL);
 444         if( isOutbound )
 445         {
 446                 td_data = OutData ? EHCI_int_AllocateTD(Cont, PID_OUT, (void*)OutData, OutLength, NULL, NULL) : NULL;
 447                 td_status = EHCI_int_AllocateTD(Cont, PID_IN, InData, InLength, Cb, CbData);
 448         }
 449         else
 450         {
 451                 td_data = InData ? EHCI_int_AllocateTD(Cont, PID_IN, InData, InLength, NULL, NULL) : NULL;
 452                 td_status = EHCI_int_AllocateTD(Cont, PID_OUT, (void*)OutData, OutLength, Cb, CbData);
 453                 td_status->Token |= (1 << 15);  // IOC
 454         }
 455
 456         // Append TDs
 457         if( td_data ) {
 458                 td_setup->Link = MM_GetPhysAddr(td_data);
 459                 td_data->Link = MM_GetPhysAddr(td_status) | 1;
 460                 td_data->Token |= (1 << 8);     // Active
 461         }
 462         else {
 463                 td_setup->Link = MM_GetPhysAddr(td_status) | 1;
 464         }
 465         td_setup->Token |= (1 << 8);    // Active
 466         td_status->Token |= (1 << 8);
 467         EHCI_int_AppendTD(Cont, Dest, td_setup);
 468
 469         return td_status;
 470 }
 471
 472 void *EHCI_SendBulk(void *Ptr, void *Dest, tUSBHostCb Cb, void *CbData, int Dir, void *Data, size_t Length)
 473 {
 474         tEHCI_Controller        *Cont = Ptr;
 475
 476         // Sanity check the pointer
 477         // - Can't be NULL or an isoch
 478         if( (tVAddr)Dest <= 256*16 )
 479                 return NULL;
 480
 481         // Allocate single TD
 482         tEHCI_qTD       *td = EHCI_int_AllocateTD(Cont, (Dir ? PID_OUT : PID_IN), Data, Length, Cb, CbData);
 483         EHCI_int_AppendTD(Cont, Dest, td);
 484
 485         return td;
 486 }
 487
 488 void EHCI_FreeOp(void *Ptr, void *Handle)
 489 {
 490         tEHCI_Controller        *Cont = Ptr;
 491
 492         EHCI_int_DeallocateTD(Cont, Handle);
 493 }
 494
 495 Uint32 EHCI_int_RootHub_FeatToMask(int Feat)
 496 {
 497         switch(Feat)
 498         {
 499         case PORT_RESET:        return PORTSC_PortReset;
 500         case PORT_ENABLE:       return PORTSC_PortEnabled;
 501         default:
 502                 Log_Warning("EHCI", "Unknown root hub port feature %i", Feat);
 503                 return 0;
 504         }
 505 }
 506
 507 void EHCI_RootHub_SetPortFeature(void *Ptr, int Port, int Feat)
 508 {
 509         tEHCI_Controller        *Cont = Ptr;
 510         if(Port >= Cont->nPorts)        return;
 511
 512         Cont->OpRegs->PortSC[Port] |= EHCI_int_RootHub_FeatToMask(Feat);
 513 }
 514
 515 void EHCI_RootHub_ClearPortFeature(void *Ptr, int Port, int Feat)
 516 {
 517         tEHCI_Controller        *Cont = Ptr;
 518         if(Port >= Cont->nPorts)        return;
 519
 520         Cont->OpRegs->PortSC[Port] &= ~EHCI_int_RootHub_FeatToMask(Feat);
 521 }
 522
 523 int EHCI_RootHub_GetPortStatus(void *Ptr, int Port, int Flag)
 524 {
 525         tEHCI_Controller        *Cont = Ptr;
 526         if(Port >= Cont->nPorts)        return 0;
 527
 528         return !!(Cont->OpRegs->PortSC[Port] & EHCI_int_RootHub_FeatToMask(Flag));
 529 }
 530
 531 // --------------------------------------------------------------------
 532 // Internals
 533 // --------------------------------------------------------------------
 534 tEHCI_qTD *EHCI_int_GetTDFromPhys(tEHCI_Controller *Cont, Uint32 Addr)
 535 {
 536         if( Addr == 0 ) return NULL;
 537         LOG("%p + (%x - %x)", Cont->TDPool, Addr, MM_GetPhysAddr(Cont->TDPool));
 538         return Cont->TDPool + (Addr - MM_GetPhysAddr(Cont->TDPool))/sizeof(tEHCI_qTD);
 539 }
 540
 541 tEHCI_qTD *EHCI_int_AllocateTD(tEHCI_Controller *Cont, int PID, void *Data, size_t Length, tUSBHostCb Cb, void *CbData)
 542 {
 543 //      Semaphore_Wait(&Cont->TDSemaphore, 1);
 544         Mutex_Acquire(&Cont->TDPoolMutex);
 545         for( int i = 0; i < TD_POOL_SIZE; i ++ )
 546         {
 547                 if( ((Cont->TDPool[i].Token >> 8) & 3) != 3 )
 548                         continue ;
 549                 Cont->TDPool[i].Token = (PID << 8) | (Length << 16);
 550                 // NOTE: Assumes that `Length` is <= PAGE_SIZE
 551                 Cont->TDPool[i].Pages[0] = MM_GetPhysAddr(Data);
 552                 if( (Cont->TDPool[i].Pages[0] & (PAGE_SIZE-1)) + Length - 1 > PAGE_SIZE )
 553                         Cont->TDPool[i].Pages[1] = MM_GetPhysAddr((char*)Data + Length - 1) & ~(PAGE_SIZE-1);
 554                 Mutex_Release(&Cont->TDPoolMutex);
 555                 LOG("Allocated %p for PID %i on %p", &Cont->TDPool[i], PID, Cont);
 556                 return &Cont->TDPool[i];
 557         }
 558
 559         Mutex_Release(&Cont->TDPoolMutex);
 560         return NULL;
 561 }
 562
 563 void EHCI_int_DeallocateTD(tEHCI_Controller *Cont, tEHCI_qTD *TD)
 564 {
 565         UNIMPLEMENTED();
 566 }
 567
 568 void EHCI_int_AppendTD(tEHCI_Controller *Cont, tEHCI_QH *QH, tEHCI_qTD *TD)
 569 {
 570         tEHCI_qTD       *ptd = NULL;
 571         Uint32  link = QH->CurrentTD;
 572
 573         // TODO: Need locking and validation here
 574         while( link && !(link & 1) )
 575         {
 576                 ptd = EHCI_int_GetTDFromPhys(Cont, link);
 577                 link = ptd->Link;
 578         }
 579         // TODO: Figure out how to follow this properly
 580         if( !ptd ) {
 581                 QH->CurrentTD = MM_GetPhysAddr(TD);
 582                 LOG("Appended %p to beginning of %p", TD, QH);
 583         }
 584         else {
 585                 ptd->Link = MM_GetPhysAddr(TD);
 586                 LOG("Appended %p to end of %p", TD, QH);
 587         }
 588 }
 589
 590 tEHCI_QH *EHCI_int_AllocateQH(tEHCI_Controller *Cont, int Endpoint, size_t MaxPacketSize)
 591 {
 592         tEHCI_QH        *ret;
 593         Mutex_Acquire(&Cont->QHPoolMutex);
 594         for( int i = 0; i < QH_POOL_SIZE; i ++ )
 595         {
 596                 if( !MM_GetPhysAddr( Cont->QHPools[i/QH_POOL_NPERPAGE] ) ) {
 597                         tPAddr  tmp;
 598                         Cont->QHPools[i/QH_POOL_NPERPAGE] = (void*)MM_AllocDMA(1, 32, &tmp);
 599                         memset(Cont->QHPools[i/QH_POOL_NPERPAGE], 0, PAGE_SIZE);
 600                 }
 601
 602                 ret = &Cont->QHPools[i/QH_POOL_NPERPAGE][i%QH_POOL_NPERPAGE];
 603                 if( ret->HLink == 0 ) {
 604                         ret->HLink = 1;
 605                         ret->Overlay.Link = 1;
 606                         ret->Endpoint = (Endpoint >> 4) | 0x80 | ((Endpoint & 0xF) << 8)
 607                                 | (MaxPacketSize << 16);
 608                         // TODO: Endpoint speed (13:12) 0:Full, 1:Low, 2:High
 609                         // TODO: Control Endpoint Flag (27) 0:*, 1:Full/Low Control
 610                         Mutex_Release(&Cont->QHPoolMutex);
 611                         return ret;
 612                 }
 613         }
 614         Mutex_Release(&Cont->QHPoolMutex);
 615         return NULL;
 616 }
 617
 618 void EHCI_int_DeallocateQH(tEHCI_Controller *Cont, tEHCI_QH *QH)
 619 {
 620         // TODO: Ensure it's unused (somehow)
 621         QH->HLink = 0;
 622 }
 623
 624 void EHCI_int_HandlePortConnectChange(tEHCI_Controller *Cont, int Port)
 625 {
 626         // Connect Event
 627         if( Cont->OpRegs->PortSC[Port] & PORTSC_CurrentConnectStatus )
 628         {
 629                 // Is the device low-speed?
 630                 if( (Cont->OpRegs->PortSC[Port] & PORTSC_LineStatus_MASK) == PORTSC_LineStatus_Kstate )
 631                 {
 632                         LOG("Low speed device on %p Port %i, giving to companion", Cont, Port);
 633                         Cont->OpRegs->PortSC[Port] |= PORTSC_PortOwner;
 634                 }
 635                 // not a low-speed device, EHCI reset
 636                 else
 637                 {
 638                         LOG("Device connected on %p #%i", Cont, Port);
 639                         // Reset procedure.
 640                         USB_PortCtl_BeginReset(Cont->RootHub, Port);
 641                 }
 642         }
 643         // Disconnect Event
 644         else
 645         {
 646                 if( Cont->OpRegs->PortSC[Port] & PORTSC_PortOwner ) {
 647                         LOG("Companion port %i disconnected, taking it back", Port);
 648                         Cont->OpRegs->PortSC[Port] &= ~PORTSC_PortOwner;
 649                 }
 650                 else {
 651                         LOG("Port %i disconnected", Port);
 652                         USB_DeviceDisconnected(Cont->RootHub, Port);
 653                 }
 654         }
 655 }
 656
 657 void EHCI_int_InterruptThread(void *ControllerPtr)
 658 {
 659         tEHCI_Controller        *Cont = ControllerPtr;
 660         while(Cont->OpRegs)
 661         {
 662                 Uint32  events;
 663
 664                 LOG("sleeping for events");
 665                 events = Threads_WaitEvents(EHCI_THREADEVENT_IOC|EHCI_THREADEVENT_PORTSC);
 666                 if( !events ) {
 667                         // TODO: Should this cause a termination?
 668                 }
 669                 LOG("events = 0x%x", events);
 670
 671                 if( events & EHCI_THREADEVENT_IOC )
 672                 {
 673                         // IOC, Do whatever it is you do
 674                 }
 675
 676                 // Port status change interrupt
 677                 if( events & EHCI_THREADEVENT_PORTSC )
 678                 {
 679                         // Check for port status changes
 680                         for(int i = 0; i < Cont->nPorts; i ++ )
 681                         {
 682                                 Uint32  sts = Cont->OpRegs->PortSC[i];
 683                                 LOG("Port %i: sts = %x", i, sts);
 684                                 Cont->OpRegs->PortSC[i] = sts;
 685                                 if( sts & PORTSC_ConnectStatusChange )
 686                                         EHCI_int_HandlePortConnectChange(Cont, i);
 687
 688                                 if( sts & PORTSC_PortEnableChange )
 689                                 {
 690                                         // Handle enable/disable
 691                                 }
 692
 693                                 if( sts & PORTSC_OvercurrentChange )
 694                                 {
 695                                         // Handle over-current change
 696                                 }
 697                         }
 698                 }
 699
 700                 LOG("Going back to sleep");
 701         }
 702 }