bktr_mem.c revision 330897 
1/*
2 * This is part of the Driver for Video Capture Cards (Frame grabbers)
3 * and TV Tuner cards using the Brooktree Bt848, Bt848A, Bt849A, Bt878, Bt879
4 * chipset.
5 * Copyright Roger Hardiman.
6 *
7 * bktr_mem : This kernel module allows us to keep our allocated
8 *            contiguous memory for the video buffer, DMA programs and VBI data
9 *            while the main bktr driver is unloaded and reloaded.
10 *            This avoids the problem of trying to allocate contiguous each
11 *            time the bktr driver is loaded.
12 */
13
14/*-
15 * SPDX-License-Identifier: BSD-4-Clause
16 *
17 * 1. Redistributions of source code must retain the
18 * Copyright (c) 2000 Roger Hardiman
19 * All rights reserved.
20 *
21 * Redistribution and use in source and binary forms, with or without
22 * modification, are permitted provided that the following conditions
23 * are met:
24 * 1. Redistributions of source code must retain the above copyright
25 *    notice, this list of conditions and the following disclaimer.
26 * 2. Redistributions in binary form must reproduce the above copyright
27 *    notice, this list of conditions and the following disclaimer in the
28 *    documentation and/or other materials provided with the distribution.
29 * 3. All advertising materials mentioning features or use of this software
30 *    must display the following acknowledgement:
31 *      This product includes software developed by Roger Hardiman
32 * 4. The name of the author may not be used to endorse or promote products
33 *    derived from this software without specific prior written permission.
34 *
35 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
36 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
37 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
38 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
39 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
40 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
41 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
42 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
43 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
44 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
45 * POSSIBILITY OF SUCH DAMAGE.
46 */
47
48#include <sys/cdefs.h>
49__FBSDID("$FreeBSD: stable/11/sys/dev/bktr/bktr_mem.c 330897 2018-03-14 03:19:51Z eadler $");
50
51#include <sys/param.h>
52#include <sys/kernel.h>
53#include <sys/module.h>
54#include <sys/systm.h>
55#include <dev/bktr/bktr_mem.h>
56
57struct memory_pointers {
58	int		addresses_stored;
59	vm_offset_t	dma_prog;
60	vm_offset_t	odd_dma_prog;
61	vm_offset_t	vbidata;
62	vm_offset_t	vbibuffer;
63	vm_offset_t	buf;
64} memory_pointers;
65
66static struct memory_pointers memory_list[BKTR_MEM_MAX_DEVICES];
67
68/*************************************************************/
69
70static int
71bktr_mem_modevent(module_t mod, int type, void *unused){
72
73	switch (type) {
74	case MOD_LOAD:
75		printf("bktr_mem: memory holder loaded\n");
76		/*
77		 * bzero((caddr_t)memory_list, sizeof(memory_list));
78		 * causes a panic. So use a simple for loop for now.
79		 */
80		{
81			int x;
82			unsigned char *d;
83
84			d = (unsigned char *)memory_list;
85			for (x = 0; x < sizeof(memory_list); x++)
86				d[x] = 0;
87		}
88		return 0;
89	case MOD_UNLOAD:
90		printf("bktr_mem: memory holder cannot be unloaded\n");
91		return EBUSY;
92	default:
93		return EOPNOTSUPP;
94		break;
95	}
96	return (0);
97}
98
99/*************************************************************/
100
101int
102bktr_has_stored_addresses(int unit)
103{
104
105	if (unit < 0 || unit >= BKTR_MEM_MAX_DEVICES) {
106		printf("bktr_mem: Unit number %d invalid\n", unit);
107		return 0;
108	}
109
110	return memory_list[unit].addresses_stored;
111}
112
113/*************************************************************/
114
115void
116bktr_store_address(int unit, int type, vm_offset_t addr)
117{
118
119	if (unit < 0 || unit >= BKTR_MEM_MAX_DEVICES) {
120		printf("bktr_mem: Unit number %d invalid for memory type %d, address %p\n",
121		       unit, type, (void *) addr);
122		return;
123	}
124
125	switch (type) {
126	case BKTR_MEM_DMA_PROG:
127		memory_list[unit].dma_prog = addr;
128		memory_list[unit].addresses_stored = 1;
129		break;
130	case BKTR_MEM_ODD_DMA_PROG:
131		memory_list[unit].odd_dma_prog = addr;
132		memory_list[unit].addresses_stored = 1;
133		break;
134	case BKTR_MEM_VBIDATA:
135		memory_list[unit].vbidata = addr;
136		memory_list[unit].addresses_stored = 1;
137		break;
138	case BKTR_MEM_VBIBUFFER:
139		memory_list[unit].vbibuffer = addr;
140		memory_list[unit].addresses_stored = 1;
141		break;
142	case BKTR_MEM_BUF:
143		memory_list[unit].buf = addr;
144		memory_list[unit].addresses_stored = 1;
145		break;
146	default:
147		printf("bktr_mem: Invalid memory type %d for bktr%d, address %p\n",
148			type, unit, (void *)addr);
149		break;
150	}
151}
152
153/*************************************************************/
154
155vm_offset_t
156bktr_retrieve_address(int unit, int type)
157{
158
159	if (unit < 0 || unit >= BKTR_MEM_MAX_DEVICES) {
160		printf("bktr_mem: Unit number %d too large for memory type %d\n",
161			unit, type);
162		return (0);
163	}
164	switch (type) {
165	case BKTR_MEM_DMA_PROG:
166		return memory_list[unit].dma_prog;
167	case BKTR_MEM_ODD_DMA_PROG:
168		return memory_list[unit].odd_dma_prog;
169	case BKTR_MEM_VBIDATA:
170		return memory_list[unit].vbidata;
171	case BKTR_MEM_VBIBUFFER:
172		return memory_list[unit].vbibuffer;
173	case BKTR_MEM_BUF:
174		return memory_list[unit].buf;
175	default:
176		printf("bktr_mem: Invalid memory type %d for bktr%d",
177		       type, unit);
178		return (0);
179	}
180}
181
182/*************************************************************/
183
184static moduledata_t bktr_mem_mod = {
185	"bktr_mem",
186	bktr_mem_modevent,
187	0
188};
189
190/*
191 * The load order is First and module type is Driver to make sure bktr_mem
192 * loads (and initialises) before bktr when both are loaded together.
193 */
194DECLARE_MODULE(bktr_mem, bktr_mem_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
195MODULE_VERSION(bktr_mem, 1);
196