linux/drivers/usb/host/ohci-mem.c

139 lines
3.3 KiB
C

/*
* OHCI HCD (Host Controller Driver) for USB.
*
* (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
* (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
*
* This file is licenced under the GPL.
*/
/*-------------------------------------------------------------------------*/
/*
* OHCI deals with three types of memory:
* - data used only by the HCD ... kmalloc is fine
* - async and periodic schedules, shared by HC and HCD ... these
* need to use dma_pool or dma_alloc_coherent
* - driver buffers, read/written by HC ... the hcd glue or the
* device driver provides us with dma addresses
*
* There's also "register" data, which is memory mapped.
* No memory seen by this driver (or any HCD) may be paged out.
*/
/*-------------------------------------------------------------------------*/
static void ohci_hcd_init (struct ohci_hcd *ohci)
{
ohci->next_statechange = jiffies;
spin_lock_init (&ohci->lock);
INIT_LIST_HEAD (&ohci->pending);
}
/*-------------------------------------------------------------------------*/
static int ohci_mem_init (struct ohci_hcd *ohci)
{
ohci->td_cache = dma_pool_create ("ohci_td",
ohci_to_hcd(ohci)->self.controller,
sizeof (struct td),
32 /* byte alignment */,
0 /* no page-crossing issues */);
if (!ohci->td_cache)
return -ENOMEM;
ohci->ed_cache = dma_pool_create ("ohci_ed",
ohci_to_hcd(ohci)->self.controller,
sizeof (struct ed),
16 /* byte alignment */,
0 /* no page-crossing issues */);
if (!ohci->ed_cache) {
dma_pool_destroy (ohci->td_cache);
return -ENOMEM;
}
return 0;
}
static void ohci_mem_cleanup (struct ohci_hcd *ohci)
{
if (ohci->td_cache) {
dma_pool_destroy (ohci->td_cache);
ohci->td_cache = NULL;
}
if (ohci->ed_cache) {
dma_pool_destroy (ohci->ed_cache);
ohci->ed_cache = NULL;
}
}
/*-------------------------------------------------------------------------*/
/* ohci "done list" processing needs this mapping */
static inline struct td *
dma_to_td (struct ohci_hcd *hc, dma_addr_t td_dma)
{
struct td *td;
td_dma &= TD_MASK;
td = hc->td_hash [TD_HASH_FUNC(td_dma)];
while (td && td->td_dma != td_dma)
td = td->td_hash;
return td;
}
/* TDs ... */
static struct td *
td_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
{
dma_addr_t dma;
struct td *td;
td = dma_pool_alloc (hc->td_cache, mem_flags, &dma);
if (td) {
/* in case hc fetches it, make it look dead */
memset (td, 0, sizeof *td);
td->hwNextTD = cpu_to_hc32 (hc, dma);
td->td_dma = dma;
/* hashed in td_fill */
}
return td;
}
static void
td_free (struct ohci_hcd *hc, struct td *td)
{
struct td **prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)];
while (*prev && *prev != td)
prev = &(*prev)->td_hash;
if (*prev)
*prev = td->td_hash;
else if ((td->hwINFO & cpu_to_hc32(hc, TD_DONE)) != 0)
ohci_dbg (hc, "no hash for td %p\n", td);
dma_pool_free (hc->td_cache, td, td->td_dma);
}
/*-------------------------------------------------------------------------*/
/* EDs ... */
static struct ed *
ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
{
dma_addr_t dma;
struct ed *ed;
ed = dma_pool_alloc (hc->ed_cache, mem_flags, &dma);
if (ed) {
memset (ed, 0, sizeof (*ed));
INIT_LIST_HEAD (&ed->td_list);
ed->dma = dma;
}
return ed;
}
static void
ed_free (struct ohci_hcd *hc, struct ed *ed)
{
dma_pool_free (hc->ed_cache, ed, ed->dma);
}