summaryrefslogtreecommitdiffstats
path: root/drivers/media/dvb/firesat/cmp.c
blob: d1bafba615e4bf5e86b2bc806d4e51214395c9b5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
/*
 * FireDTV driver (formerly known as FireSAT)
 *
 * Copyright (C) 2004 Andreas Monitzer <andy@monitzer.com>
 * Copyright (C) 2008 Henrik Kurelid <henrik@kurelid.se>
 *
 *	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.
 */

#include <linux/kernel.h>
#include <linux/mutex.h>
#include <linux/types.h>

#include <hosts.h>
#include <ieee1394.h>
#include <ieee1394_core.h>
#include <ieee1394_transactions.h>
#include <nodemgr.h>

#include "avc_api.h"
#include "cmp.h"
#include "firesat.h"

typedef struct _OPCR
{
	__u8 PTPConnCount    : 6 ; // Point to point connect. counter
	__u8 BrConnCount     : 1 ; // Broadcast connection counter
	__u8 OnLine          : 1 ; // On Line

	__u8 ChNr            : 6 ; // Channel number
	__u8 Res             : 2 ; // Reserved

	__u8 PayloadHi       : 2 ; // Payoad high bits
	__u8 OvhdID          : 4 ; // Overhead ID
	__u8 DataRate        : 2 ; // Data Rate

	__u8 PayloadLo           ; // Payoad low byte
} OPCR ;

#define FIRESAT_SPEED IEEE1394_SPEED_400

static int cmp_read(struct firesat *firesat, void *buf, u64 addr, size_t len)
{
	int ret;

	if (mutex_lock_interruptible(&firesat->avc_mutex))
		return -EINTR;

	ret = hpsb_read(firesat->host, firesat->nodeentry->nodeid,
			firesat->nodeentry->generation, addr, buf, len);

	mutex_unlock(&firesat->avc_mutex);
	return ret;
}

static int cmp_lock(struct firesat *firesat, quadlet_t *data, u64 addr,
		quadlet_t arg, int ext_tcode)
{
	int ret;

	if (mutex_lock_interruptible(&firesat->avc_mutex))
		return -EINTR;

	ret = hpsb_lock(firesat->host, firesat->nodeentry->nodeid,
			firesat->nodeentry->generation,
			addr, ext_tcode, data, arg);

	mutex_unlock(&firesat->avc_mutex);
	return ret;
}

//try establishing a point-to-point connection (may be interrupted by a busreset
int try_CMPEstablishPPconnection(struct firesat *firesat, int output_plug, int iso_channel) {
	unsigned int BWU; //bandwidth to allocate

	quadlet_t old_oPCR,test_oPCR = 0x0;
	u64 oPCR_address=0xfffff0000904ull+(output_plug << 2);
	int result=cmp_read(firesat, &test_oPCR, oPCR_address, 4);

/* 	printk(KERN_INFO "%s: nodeid = %d\n",__func__,firesat->nodeentry->nodeid); */

	if (result < 0) {
		printk("%s: cannot read oPCR\n", __func__);
		return result;
	} else {
/* 		printk(KERN_INFO "%s: oPCR = %08x\n",__func__,test_oPCR); */
		do {
			OPCR *hilf= (OPCR*) &test_oPCR;

			if (!hilf->OnLine) {
				printk("%s: Output offline; oPCR: %08x\n", __func__, test_oPCR);
				return -EBUSY;
			} else {
				quadlet_t new_oPCR;

				old_oPCR=test_oPCR;
				if (hilf->PTPConnCount) {
					if (hilf->ChNr != iso_channel) {
						printk("%s: Output plug has already connection on channel %u; cannot change it to channel %u\n",__func__,hilf->ChNr,iso_channel);
						return -EBUSY;
					} else
						printk(KERN_INFO "%s: Overlaying existing connection; connection counter was: %u\n",__func__, hilf->PTPConnCount);
					BWU=0; //we allocate no bandwidth (is this necessary?)
				} else {
					hilf->ChNr=iso_channel;
					hilf->DataRate=FIRESAT_SPEED;

					hilf->OvhdID=0;      //FIXME: that is for worst case -> optimize
					BWU=hilf->OvhdID?hilf->OvhdID*32:512;
					BWU += (hilf->PayloadLo + (hilf->PayloadHi << 8) +3) * (2 << (3-hilf->DataRate));
/*					if (allocate_1394_resources(iso_channel,BWU))
					{
						cout << "Allocation of resources failed\n";
						return -2;
					}*/
				}

				hilf->PTPConnCount++;
				new_oPCR=test_oPCR;
/* 				printk(KERN_INFO "%s: trying compare_swap...\n",__func__); */
/* 				printk(KERN_INFO "%s: oPCR_old: %08x, oPCR_new: %08x\n",__func__, old_oPCR, new_oPCR); */
				result=cmp_lock(firesat, &test_oPCR, oPCR_address, old_oPCR, 2);

				if (result < 0) {
					printk("%s: cannot compare_swap oPCR\n",__func__);
					return result;
				}
				if ((old_oPCR != test_oPCR) && (!((OPCR*) &old_oPCR)->PTPConnCount))
				{
					printk("%s: change of oPCR failed -> freeing resources\n",__func__);
//					hilf= (OPCR*) &new_oPCR;
//					unsigned int BWU=hilf->OvhdID?hilf->OvhdID*32:512;
//					BWU += (hilf->Payload+3) * (2 << (3-hilf->DataRate));
/*					if (deallocate_1394_resources(iso_channel,BWU))
					{

						cout << "Deallocation of resources failed\n";
						return -3;
					}*/
				}
			}
		}
		while (old_oPCR != test_oPCR);
	}
	return 0;
}

//try breaking a point-to-point connection (may be interrupted by a busreset
int try_CMPBreakPPconnection(struct firesat *firesat, int output_plug,int iso_channel) {
	quadlet_t old_oPCR,test_oPCR;

	u64 oPCR_address=0xfffff0000904ull+(output_plug << 2);
	int result=cmp_read(firesat, &test_oPCR, oPCR_address, 4);

/* 	printk(KERN_INFO "%s\n",__func__); */

	if (result < 0) {
		printk("%s: cannot read oPCR\n", __func__);
		return result;
	} else {
		do {
			OPCR *hilf= (OPCR*) &test_oPCR;

			if (!hilf->OnLine || !hilf->PTPConnCount || hilf->ChNr != iso_channel) {
				printk("%s: Output plug does not have PtP-connection on that channel; oPCR: %08x\n", __func__, test_oPCR);
				return -EINVAL;
			} else {
				quadlet_t new_oPCR;
				old_oPCR=test_oPCR;
				hilf->PTPConnCount--;
				new_oPCR=test_oPCR;

//				printk(KERN_INFO "%s: trying compare_swap...\n", __func__);
				result=cmp_lock(firesat, &test_oPCR, oPCR_address, old_oPCR, 2);
				if (result < 0) {
					printk("%s: cannot compare_swap oPCR\n",__func__);
					return result;
				}
			}

		} while (old_oPCR != test_oPCR);

/*		hilf = (OPCR*) &old_oPCR;
		if (hilf->PTPConnCount == 1) { // if we were the last owner of this connection
			cout << "deallocating 1394 resources\n";
			unsigned int BWU=hilf->OvhdID?hilf->OvhdID*32:512;
			BWU += (hilf->PayloadLo + (hilf->PayloadHi << 8) +3) * (2 << (3-hilf->DataRate));
			if (deallocate_1394_resources(iso_channel,BWU))
			{
				cout << "Deallocation of resources failed\n";
				return -3;
			}
		}*/
    }
	return 0;
}