You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
105 lines
3.1 KiB
105 lines
3.1 KiB
20 years ago
|
|
||
|
|
/*
|
||
|
|
**********************************************************************
|
||
|
|
* emuadxmg.c - Address space manager for emu10k1 driver
|
||
|
|
* Copyright 1999, 2000 Creative Labs, Inc.
|
||
|
|
*
|
||
|
|
**********************************************************************
|
||
|
|
*
|
||
|
|
* Date Author Summary of changes
|
||
|
|
* ---- ------ ------------------
|
||
|
|
* October 20, 1999 Bertrand Lee base code release
|
||
|
|
*
|
||
|
|
**********************************************************************
|
||
|
|
*
|
||
|
|
* 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.
|
||
|
|
*
|
||
|
|
**********************************************************************
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "hwaccess.h"
|
||
|
|
|
||
|
|
/* Allocates emu address space */
|
||
|
|
|
||
|
|
int emu10k1_addxmgr_alloc(u32 size, struct emu10k1_card *card)
|
||
|
|
{
|
||
|
|
u16 *pagetable = card->emupagetable;
|
||
|
|
u16 index = 0;
|
||
|
|
u16 numpages;
|
||
|
|
unsigned long flags;
|
||
|
|
|
||
|
|
/* Convert bytes to pages */
|
||
|
|
numpages = (size / EMUPAGESIZE) + ((size % EMUPAGESIZE) ? 1 : 0);
|
||
|
|
|
||
|
|
spin_lock_irqsave(&card->lock, flags);
|
||
|
|
|
||
|
|
while (index < (MAXPAGES - 1)) {
|
||
|
|
if (pagetable[index] & 0x8000) {
|
||
|
|
/* This block of pages is in use, jump to the start of the next block. */
|
||
|
|
index += (pagetable[index] & 0x7fff);
|
||
|
|
} else {
|
||
|
|
/* Found free block */
|
||
|
|
if (pagetable[index] >= numpages) {
|
||
|
|
|
||
|
|
/* Block is large enough */
|
||
|
|
|
||
|
|
/* If free block is larger than the block requested
|
||
|
|
* then adjust the size of the block remaining */
|
||
|
|
if (pagetable[index] > numpages)
|
||
|
|
pagetable[index + numpages] = pagetable[index] - numpages;
|
||
|
|
|
||
|
|
pagetable[index] = (numpages | 0x8000); /* Mark block as used */
|
||
|
|
|
||
|
|
spin_unlock_irqrestore(&card->lock, flags);
|
||
|
|
|
||
|
|
return index;
|
||
|
|
} else {
|
||
|
|
/* Block too small, jump to the start of the next block */
|
||
|
|
index += pagetable[index];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
spin_unlock_irqrestore(&card->lock, flags);
|
||
|
|
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Frees a previously allocated emu address space. */
|
||
|
|
|
||
|
|
void emu10k1_addxmgr_free(struct emu10k1_card *card, int index)
|
||
|
|
{
|
||
|
|
u16 *pagetable = card->emupagetable;
|
||
|
|
u16 origsize = 0;
|
||
|
|
unsigned long flags;
|
||
|
|
|
||
|
|
spin_lock_irqsave(&card->lock, flags);
|
||
|
|
|
||
|
|
if (pagetable[index] & 0x8000) {
|
||
|
|
/* Block is allocated - mark block as free */
|
||
|
|
origsize = pagetable[index] & 0x7fff;
|
||
|
|
pagetable[index] = origsize;
|
||
|
|
|
||
|
|
/* If next block is free, we concat both blocks */
|
||
|
|
if (!(pagetable[index + origsize] & 0x8000))
|
||
|
|
pagetable[index] += pagetable[index + origsize] & 0x7fff;
|
||
|
|
}
|
||
|
|
|
||
|
|
spin_unlock_irqrestore(&card->lock, flags);
|
||
|
|
|
||
|
|
return;
|
||
|
|
}
|