1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 2005 MIPS Technologies, Inc. All rights reserved.
7 * Copyright (C) 2013 Imagination Technologies Ltd.
8 */
9 #include <linux/device.h>
10 #include <linux/fs.h>
11 #include <linux/err.h>
12 #include <linux/wait.h>
13 #include <linux/sched.h>
14 #include <linux/smp.h>
15
16 #include <asm/mips_mt.h>
17 #include <asm/vpe.h>
18 #include <asm/rtlx.h>
19
20 static int major;
21
rtlx_interrupt(void)22 static void rtlx_interrupt(void)
23 {
24 int i;
25 struct rtlx_info *info;
26 struct rtlx_info **p = vpe_get_shared(aprp_cpu_index());
27
28 if (p == NULL || *p == NULL)
29 return;
30
31 info = *p;
32
33 if (info->ap_int_pending == 1 && smp_processor_id() == 0) {
34 for (i = 0; i < RTLX_CHANNELS; i++) {
35 wake_up(&channel_wqs[i].lx_queue);
36 wake_up(&channel_wqs[i].rt_queue);
37 }
38 info->ap_int_pending = 0;
39 }
40 }
41
_interrupt_sp(void)42 void _interrupt_sp(void)
43 {
44 smp_send_reschedule(aprp_cpu_index());
45 }
46
rtlx_module_init(void)47 int __init rtlx_module_init(void)
48 {
49 struct device *dev;
50 int i, err;
51
52 if (!cpu_has_mipsmt) {
53 pr_warn("VPE loader: not a MIPS MT capable processor\n");
54 return -ENODEV;
55 }
56
57 if (num_possible_cpus() - aprp_cpu_index() < 1) {
58 pr_warn("No TCs reserved for AP/SP, not initializing RTLX.\n"
59 "Pass maxcpus=<n> argument as kernel argument\n");
60
61 return -ENODEV;
62 }
63
64 major = register_chrdev(0, RTLX_MODULE_NAME, &rtlx_fops);
65 if (major < 0) {
66 pr_err("rtlx_module_init: unable to register device\n");
67 return major;
68 }
69
70 /* initialise the wait queues */
71 for (i = 0; i < RTLX_CHANNELS; i++) {
72 init_waitqueue_head(&channel_wqs[i].rt_queue);
73 init_waitqueue_head(&channel_wqs[i].lx_queue);
74 atomic_set(&channel_wqs[i].in_open, 0);
75 mutex_init(&channel_wqs[i].mutex);
76
77 dev = device_create(mt_class, NULL, MKDEV(major, i), NULL,
78 "%s%d", RTLX_MODULE_NAME, i);
79 if (IS_ERR(dev)) {
80 while (i--)
81 device_destroy(mt_class, MKDEV(major, i));
82
83 err = PTR_ERR(dev);
84 goto out_chrdev;
85 }
86 }
87
88 /* set up notifiers */
89 rtlx_notify.start = rtlx_starting;
90 rtlx_notify.stop = rtlx_stopping;
91 vpe_notify(aprp_cpu_index(), &rtlx_notify);
92
93 if (cpu_has_vint) {
94 aprp_hook = rtlx_interrupt;
95 } else {
96 pr_err("APRP RTLX init on non-vectored-interrupt processor\n");
97 err = -ENODEV;
98 goto out_class;
99 }
100
101 return 0;
102
103 out_class:
104 for (i = 0; i < RTLX_CHANNELS; i++)
105 device_destroy(mt_class, MKDEV(major, i));
106 out_chrdev:
107 unregister_chrdev(major, RTLX_MODULE_NAME);
108
109 return err;
110 }
111
rtlx_module_exit(void)112 void __exit rtlx_module_exit(void)
113 {
114 int i;
115
116 for (i = 0; i < RTLX_CHANNELS; i++)
117 device_destroy(mt_class, MKDEV(major, i));
118
119 unregister_chrdev(major, RTLX_MODULE_NAME);
120
121 aprp_hook = NULL;
122 }
123