📄 ehci-mem.c
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/*
* Copyright (c) 2001 by David Brownell
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* this file is part of ehci-hcd.c */
/*-------------------------------------------------------------------------*/
/*
* There's basically 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 pci_pool or pci_alloc_consistent
* - driver buffers, read/written by HC ... single shot DMA mapped
*
* There's also PCI "register" data, which is memory mapped.
* No memory seen by this driver is pagable.
*/
/*-------------------------------------------------------------------------*/
/*
* Allocator / cleanup for the per device structure
* Called by hcd init / removal code
*/
static struct usb_hcd *ehci_hcd_alloc (void)
{
struct ehci_hcd *ehci;
ehci = (struct ehci_hcd *)
kmalloc (sizeof (struct ehci_hcd), GFP_KERNEL);
if (ehci != 0) {
memset (ehci, 0, sizeof (struct ehci_hcd));
return &ehci->hcd;
}
return 0;
}
static void ehci_hcd_free (struct usb_hcd *hcd)
{
kfree (hcd_to_ehci (hcd));
}
/*-------------------------------------------------------------------------*/
/* Allocate the key transfer structures from the previously allocated pool */
static inline void ehci_qtd_init (struct ehci_qtd *qtd, dma_addr_t dma)
{
memset (qtd, 0, sizeof *qtd);
qtd->qtd_dma = dma;
qtd->hw_next = EHCI_LIST_END;
qtd->hw_alt_next = EHCI_LIST_END;
INIT_LIST_HEAD (&qtd->qtd_list);
}
static struct ehci_qtd *ehci_qtd_alloc (struct ehci_hcd *ehci, int flags)
{
struct ehci_qtd *qtd;
dma_addr_t dma;
qtd = pci_pool_alloc (ehci->qtd_pool, flags, &dma);
if (qtd != 0) {
ehci_qtd_init (qtd, dma);
}
return qtd;
}
static inline void ehci_qtd_free (struct ehci_hcd *ehci, struct ehci_qtd *qtd)
{
pci_pool_free (ehci->qtd_pool, qtd, qtd->qtd_dma);
}
static struct ehci_qh *ehci_qh_alloc (struct ehci_hcd *ehci, int flags)
{
struct ehci_qh *qh;
dma_addr_t dma;
qh = (struct ehci_qh *)
pci_pool_alloc (ehci->qh_pool, flags, &dma);
if (!qh)
return qh;
memset (qh, 0, sizeof *qh);
atomic_set (&qh->refcount, 1);
qh->qh_dma = dma;
// INIT_LIST_HEAD (&qh->qh_list);
INIT_LIST_HEAD (&qh->qtd_list);
/* dummy td enables safe urb queuing */
qh->dummy = ehci_qtd_alloc (ehci, flags);
if (qh->dummy == 0) {
ehci_dbg (ehci, "no dummy td\n");
pci_pool_free (ehci->qh_pool, qh, qh->qh_dma);
qh = 0;
}
return qh;
}
/* to share a qh (cpu threads, or hc) */
static inline struct ehci_qh *qh_get (/* ehci, */ struct ehci_qh *qh)
{
atomic_inc (&qh->refcount);
return qh;
}
static void qh_put (struct ehci_hcd *ehci, struct ehci_qh *qh)
{
if (!atomic_dec_and_test (&qh->refcount))
return;
/* clean qtds first, and know this is not linked */
if (!list_empty (&qh->qtd_list) || qh->qh_next.ptr) {
ehci_dbg (ehci, "unused qh not empty!\n");
BUG ();
}
if (qh->dummy)
ehci_qtd_free (ehci, qh->dummy);
pci_pool_free (ehci->qh_pool, qh, qh->qh_dma);
}
/*-------------------------------------------------------------------------*/
/* The queue heads and transfer descriptors are managed from pools tied
* to each of the "per device" structures.
* This is the initialisation and cleanup code.
*/
static void ehci_mem_cleanup (struct ehci_hcd *ehci)
{
if (ehci->async)
qh_put (ehci, ehci->async);
ehci->async = 0;
/* PCI consistent memory and pools */
if (ehci->qtd_pool)
pci_pool_destroy (ehci->qtd_pool);
ehci->qtd_pool = 0;
if (ehci->qh_pool) {
pci_pool_destroy (ehci->qh_pool);
ehci->qh_pool = 0;
}
if (ehci->itd_pool)
pci_pool_destroy (ehci->itd_pool);
ehci->itd_pool = 0;
if (ehci->sitd_pool)
pci_pool_destroy (ehci->sitd_pool);
ehci->sitd_pool = 0;
if (ehci->periodic)
pci_free_consistent (ehci->hcd.pdev,
ehci->periodic_size * sizeof (u32),
ehci->periodic, ehci->periodic_dma);
ehci->periodic = 0;
/* shadow periodic table */
if (ehci->pshadow)
kfree (ehci->pshadow);
ehci->pshadow = 0;
}
/* remember to add cleanup code (above) if you add anything here */
static int ehci_mem_init (struct ehci_hcd *ehci, int flags)
{
int i;
/* QTDs for control/bulk/intr transfers */
ehci->qtd_pool = pci_pool_create ("ehci_qtd", ehci->hcd.pdev,
sizeof (struct ehci_qtd),
32 /* byte alignment (for hw parts) */,
4096 /* can't cross 4K */,
flags);
if (!ehci->qtd_pool) {
goto fail;
}
/* QHs for control/bulk/intr transfers */
ehci->qh_pool = pci_pool_create ("ehci_qh", ehci->hcd.pdev,
sizeof (struct ehci_qh),
32 /* byte alignment (for hw parts) */,
4096 /* can't cross 4K */,
flags);
if (!ehci->qh_pool) {
goto fail;
}
ehci->async = ehci_qh_alloc (ehci, flags);
if (!ehci->async) {
goto fail;
}
/* ITD for high speed ISO transfers */
ehci->itd_pool = pci_pool_create ("ehci_itd", ehci->hcd.pdev,
sizeof (struct ehci_itd),
32 /* byte alignment (for hw parts) */,
4096 /* can't cross 4K */,
flags);
if (!ehci->itd_pool) {
goto fail;
}
/* SITD for full/low speed split ISO transfers */
ehci->sitd_pool = pci_pool_create ("ehci_sitd", ehci->hcd.pdev,
sizeof (struct ehci_sitd),
32 /* byte alignment (for hw parts) */,
4096 /* can't cross 4K */,
flags);
if (!ehci->sitd_pool) {
goto fail;
}
/* Hardware periodic table */
ehci->periodic = (u32 *)
pci_alloc_consistent (ehci->hcd.pdev,
ehci->periodic_size * sizeof (u32),
&ehci->periodic_dma);
if (ehci->periodic == 0) {
goto fail;
}
for (i = 0; i < ehci->periodic_size; i++)
ehci->periodic [i] = EHCI_LIST_END;
/* software shadow of hardware table */
ehci->pshadow = kmalloc (ehci->periodic_size * sizeof (void *), flags);
if (ehci->pshadow == 0) {
goto fail;
}
memset (ehci->pshadow, 0, ehci->periodic_size * sizeof (void *));
return 0;
fail:
ehci_dbg (ehci, "couldn't init memory\n");
ehci_mem_cleanup (ehci);
return -ENOMEM;
}
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