drivers/usb/host/ohci-mem.c

   1 // SPDX-License-Identifier: GPL-1.0+
   2 /*
   3  * OHCI HCD (Host Controller Driver) for USB.
   4  *
   5  * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
   6  * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
   7  *
   8  * This file is licenced under the GPL.
   9  */
  10
  11 /*-------------------------------------------------------------------------*/
  12
  13 /*
  14  * OHCI deals with three types of memory:
  15  *      - data used only by the HCD ... kmalloc is fine
  16  *      - async and periodic schedules, shared by HC and HCD ... these
  17  *        need to use dma_pool or dma_alloc_coherent
  18  *      - driver buffers, read/written by HC ... the hcd glue or the
  19  *        device driver provides us with dma addresses
  20  *
  21  * There's also "register" data, which is memory mapped.
  22  * No memory seen by this driver (or any HCD) may be paged out.
  23  */
  24
  25 /*-------------------------------------------------------------------------*/
  26
  27 static void ohci_hcd_init (struct ohci_hcd *ohci)
  28 {
  29         ohci->next_statechange = jiffies;
  30         spin_lock_init (&ohci->lock);
  31         INIT_LIST_HEAD (&ohci->pending);
  32         INIT_LIST_HEAD(&ohci->eds_in_use);
  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         dma_pool_destroy(ohci->td_cache);
  61         ohci->td_cache = NULL;
  62         dma_pool_destroy(ohci->ed_cache);
  63         ohci->ed_cache = NULL;
  64 }
  65
  66 /*-------------------------------------------------------------------------*/
  67
  68 /* ohci "done list" processing needs this mapping */
  69 static inline struct td *
  70 dma_to_td (struct ohci_hcd *hc, dma_addr_t td_dma)
  71 {
  72         struct td *td;
  73
  74         td_dma &= TD_MASK;
  75         td = hc->td_hash [TD_HASH_FUNC(td_dma)];
  76         while (td && td->td_dma != td_dma)
  77                 td = td->td_hash;
  78         return td;
  79 }
  80
  81 /* TDs ... */
  82 static struct td *
  83 td_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
  84 {
  85         dma_addr_t      dma;
  86         struct td       *td;
  87
  88         td = dma_pool_zalloc (hc->td_cache, mem_flags, &dma);
  89         if (td) {
  90                 /* in case hc fetches it, make it look dead */
  91                 td->hwNextTD = cpu_to_hc32 (hc, dma);
  92                 td->td_dma = dma;
  93                 /* hashed in td_fill */
  94         }
  95         return td;
  96 }
  97
  98 static void
  99 td_free (struct ohci_hcd *hc, struct td *td)
 100 {
 101         struct td       **prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)];
 102
 103         while (*prev && *prev != td)
 104                 prev = &(*prev)->td_hash;
 105         if (*prev)
 106                 *prev = td->td_hash;
 107         else if ((td->hwINFO & cpu_to_hc32(hc, TD_DONE)) != 0)
 108                 ohci_dbg (hc, "no hash for td %p\n", td);
 109         dma_pool_free (hc->td_cache, td, td->td_dma);
 110 }
 111
 112 /*-------------------------------------------------------------------------*/
 113
 114 /* EDs ... */
 115 static struct ed *
 116 ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
 117 {
 118         dma_addr_t      dma;
 119         struct ed       *ed;
 120
 121         ed = dma_pool_zalloc (hc->ed_cache, mem_flags, &dma);
 122         if (ed) {
 123                 INIT_LIST_HEAD (&ed->td_list);
 124                 ed->dma = dma;
 125         }
 126         return ed;
 127 }
 128
 129 static void
 130 ed_free (struct ohci_hcd *hc, struct ed *ed)
 131 {
 132         dma_pool_free (hc->ed_cache, ed, ed->dma);
 133 }
 134