Linux Kernel  3.7.1
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diva_dma.c
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1 
2 /*
3  *
4  Copyright (c) Eicon Networks, 2002.
5  *
6  This source file is supplied for the use with
7  Eicon Networks range of DIVA Server Adapters.
8  *
9  Eicon File Revision : 2.1
10  *
11  This program is free software; you can redistribute it and/or modify
12  it under the terms of the GNU General Public License as published by
13  the Free Software Foundation; either version 2, or (at your option)
14  any later version.
15  *
16  This program is distributed in the hope that it will be useful,
17  but WITHOUT ANY WARRANTY OF ANY KIND WHATSOEVER INCLUDING ANY
18  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
19  See the GNU General Public License for more details.
20  *
21  You should have received a copy of the GNU General Public License
22  along with this program; if not, write to the Free Software
23  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  *
25  */
26 #include "platform.h"
27 #include "diva_dma.h"
28 /*
29  Every entry has length of PAGE_SIZE
30  and represents one single physical page
31 */
33  int busy;
34  dword phys_bus_addr; /* 32bit address as seen by the card */
35  void *local_ram_addr; /* local address as seen by the host */
36  void *addr_handle; /* handle uset to free allocated memory */
37 };
38 /*
39  Create local mapping structure and init it to default state
40 */
41 struct _diva_dma_map_entry *diva_alloc_dma_map(void *os_context, int nentries) {
42  diva_dma_map_entry_t *pmap = diva_os_malloc(0, sizeof(*pmap) * (nentries + 1));
43  if (pmap)
44  memset(pmap, 0, sizeof(*pmap) * (nentries + 1));
45  return pmap;
46 }
47 /*
48  Free local map (context should be freed before) if any
49 */
51  if (pmap) {
52  diva_os_free(0, pmap);
53  }
54 }
55 /*
56  Set information saved on the map entry
57 */
59  int nr, void *virt, dword phys,
60  void *addr_handle) {
61  pmap[nr].phys_bus_addr = phys;
62  pmap[nr].local_ram_addr = virt;
63  pmap[nr].addr_handle = addr_handle;
64 }
65 /*
66  Allocate one single entry in the map
67 */
69  int i;
70  for (i = 0; (pmap && pmap[i].local_ram_addr); i++) {
71  if (!pmap[i].busy) {
72  pmap[i].busy = 1;
73  return (i);
74  }
75  }
76  return (-1);
77 }
78 /*
79  Free one single entry in the map
80 */
82  pmap[nr].busy = 0;
83 }
84 /*
85  Get information saved on the map entry
86 */
88  void **pvirt, dword *pphys) {
89  *pphys = pmap[nr].phys_bus_addr;
90  *pvirt = pmap[nr].local_ram_addr;
91 }
92 void *diva_get_entry_handle(struct _diva_dma_map_entry *pmap, int nr) {
93  return (pmap[nr].addr_handle);
94 }