drivers/usb/host/ohci-mem.c

   1 /*
   2  * OHCI HCD (Host Controller Driver) for USB.
   3  *
   4  * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
   5  * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
   6  *
   7  * This file is licenced under the GPL.
   8  */
   9
  10 /*-------------------------------------------------------------------------*/
  11
  12 /*
  13  * There's basically three types of memory:
  14  *      - data used only by the HCD ... kmalloc is fine
  15  *      - async and periodic schedules, shared by HC and HCD ... these
  16  *        need to use dma_pool or dma_alloc_coherent
  17  *      - driver buffers, read/written by HC ... the hcd glue or the
  18  *        device driver provides us with dma addresses
  19  *
  20  * There's also PCI "register" data, which is memory mapped.
  21  * No memory seen by this driver is pagable.
  22  */
  23
  24 /*-------------------------------------------------------------------------*/
  25
  26 static void ohci_hcd_init (struct ohci_hcd *ohci)
  27 {
  28         ohci->next_statechange = jiffies;
  29         spin_lock_init (&ohci->lock);
  30         INIT_LIST_HEAD (&ohci->pending);
  31         INIT_WORK (&ohci->rh_resume, ohci_rh_resume, ohci_to_hcd(ohci));
  32         ohci->reboot_notifier.notifier_call = ohci_reboot;
  33 }
  34
  35 /*-------------------------------------------------------------------------*/
  36
  37 static int ohci_mem_init (struct ohci_hcd *ohci)
  38 {
  39         ohci->td_cache = dma_pool_create ("ohci_td",
  40                 ohci_to_hcd(ohci)->self.controller,
  41                 sizeof (struct td),
  42                 32 /* byte alignment */,
  43                 0 /* no page-crossing issues */);
  44         if (!ohci->td_cache)
  45                 return -ENOMEM;
  46         ohci->ed_cache = dma_pool_create ("ohci_ed",
  47                 ohci_to_hcd(ohci)->self.controller,
  48                 sizeof (struct ed),
  49                 16 /* byte alignment */,
  50                 0 /* no page-crossing issues */);
  51         if (!ohci->ed_cache) {
  52                 dma_pool_destroy (ohci->td_cache);
  53                 return -ENOMEM;
  54         }
  55         return 0;
  56 }
  57
  58 static void ohci_mem_cleanup (struct ohci_hcd *ohci)
  59 {
  60         if (ohci->td_cache) {
  61                 dma_pool_destroy (ohci->td_cache);
  62                 ohci->td_cache = NULL;
  63         }
  64         if (ohci->ed_cache) {
  65                 dma_pool_destroy (ohci->ed_cache);
  66                 ohci->ed_cache = NULL;
  67         }
  68 }
  69
  70 /*-------------------------------------------------------------------------*/
  71
  72 /* ohci "done list" processing needs this mapping */
  73 static inline struct td *
  74 dma_to_td (struct ohci_hcd *hc, dma_addr_t td_dma)
  75 {
  76         struct td *td;
  77
  78         td_dma &= TD_MASK;
  79         td = hc->td_hash [TD_HASH_FUNC(td_dma)];
  80         while (td && td->td_dma != td_dma)
  81                 td = td->td_hash;
  82         return td;
  83 }
  84
  85 /* TDs ... */
  86 static struct td *
  87 td_alloc (struct ohci_hcd *hc, unsigned mem_flags)
  88 {
  89         dma_addr_t      dma;
  90         struct td       *td;
  91
  92         td = dma_pool_alloc (hc->td_cache, mem_flags, &dma);
  93         if (td) {
  94                 /* in case hc fetches it, make it look dead */
  95                 memset (td, 0, sizeof *td);
  96                 td->hwNextTD = cpu_to_hc32 (hc, dma);
  97                 td->td_dma = dma;
  98                 /* hashed in td_fill */
  99         }
 100         return td;
 101 }
 102
 103 static void
 104 td_free (struct ohci_hcd *hc, struct td *td)
 105 {
 106         struct td       **prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)];
 107
 108         while (*prev && *prev != td)
 109                 prev = &(*prev)->td_hash;
 110         if (*prev)
 111                 *prev = td->td_hash;
 112         else if ((td->hwINFO & cpu_to_hc32(hc, TD_DONE)) != 0)
 113                 ohci_dbg (hc, "no hash for td %p\n", td);
 114         dma_pool_free (hc->td_cache, td, td->td_dma);
 115 }
 116
 117 /*-------------------------------------------------------------------------*/
 118
 119 /* EDs ... */
 120 static struct ed *
 121 ed_alloc (struct ohci_hcd *hc, unsigned mem_flags)
 122 {
 123         dma_addr_t      dma;
 124         struct ed       *ed;
 125
 126         ed = dma_pool_alloc (hc->ed_cache, mem_flags, &dma);
 127         if (ed) {
 128                 memset (ed, 0, sizeof (*ed));
 129                 INIT_LIST_HEAD (&ed->td_list);
 130                 ed->dma = dma;
 131         }
 132         return ed;
 133 }
 134
 135 static void
 136 ed_free (struct ohci_hcd *hc, struct ed *ed)
 137 {
 138         dma_pool_free (hc->ed_cache, ed, ed->dma);
 139 }
 140