linux/drivers/isdn/hardware/eicon/diva_dma.c

95 lines
2.8 KiB
C

/*
*
Copyright (c) Eicon Networks, 2002.
*
This source file is supplied for the use with
Eicon Networks range of DIVA Server Adapters.
*
Eicon File Revision : 2.1
*
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, or (at your option)
any later version.
*
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY OF ANY KIND WHATSOEVER INCLUDING ANY
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 "platform.h"
#include "diva_dma.h"
/*
Every entry has length of PAGE_SIZE
and represents one single physical page
*/
struct _diva_dma_map_entry {
int busy;
dword phys_bus_addr; /* 32bit address as seen by the card */
void* local_ram_addr; /* local address as seen by the host */
void* addr_handle; /* handle uset to free allocated memory */
};
/*
Create local mapping structure and init it to default state
*/
struct _diva_dma_map_entry* diva_alloc_dma_map (void* os_context, int nentries) {
diva_dma_map_entry_t* pmap = diva_os_malloc(0, sizeof(*pmap)*(nentries+1));
if (pmap)
memset (pmap, 0, sizeof(*pmap)*(nentries+1));
return pmap;
}
/*
Free local map (context should be freed before) if any
*/
void diva_free_dma_mapping (struct _diva_dma_map_entry* pmap) {
if (pmap) {
diva_os_free (0, pmap);
}
}
/*
Set information saved on the map entry
*/
void diva_init_dma_map_entry (struct _diva_dma_map_entry* pmap,
int nr, void* virt, dword phys,
void* addr_handle) {
pmap[nr].phys_bus_addr = phys;
pmap[nr].local_ram_addr = virt;
pmap[nr].addr_handle = addr_handle;
}
/*
Allocate one single entry in the map
*/
int diva_alloc_dma_map_entry (struct _diva_dma_map_entry* pmap) {
int i;
for (i = 0; (pmap && pmap[i].local_ram_addr); i++) {
if (!pmap[i].busy) {
pmap[i].busy = 1;
return (i);
}
}
return (-1);
}
/*
Free one single entry in the map
*/
void diva_free_dma_map_entry (struct _diva_dma_map_entry* pmap, int nr) {
pmap[nr].busy = 0;
}
/*
Get information saved on the map entry
*/
void diva_get_dma_map_entry (struct _diva_dma_map_entry* pmap, int nr,
void** pvirt, dword* pphys) {
*pphys = pmap[nr].phys_bus_addr;
*pvirt = pmap[nr].local_ram_addr;
}
void* diva_get_entry_handle (struct _diva_dma_map_entry* pmap, int nr) {
return (pmap[nr].addr_handle);
}