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/interrupt.h> |
15 | #include <linux/irq.h> |
16 | |
17 | #include <asm/mips_mt.h> |
18 | #include <asm/vpe.h> |
19 | #include <asm/rtlx.h> |
20 | |
21 | static int major; |
22 | |
23 | static void rtlx_dispatch(void) |
24 | { |
25 | if (read_c0_cause() & read_c0_status() & C_SW0) |
26 | do_IRQ(MIPS_CPU_IRQ_BASE + MIPS_CPU_RTLX_IRQ); |
27 | } |
28 | |
29 | /* |
30 | * Interrupt handler may be called before rtlx_init has otherwise had |
31 | * a chance to run. |
32 | */ |
33 | static irqreturn_t rtlx_interrupt(int irq, void *dev_id) |
34 | { |
35 | unsigned int vpeflags; |
36 | unsigned long flags; |
37 | int i; |
38 | |
39 | local_irq_save(flags); |
40 | vpeflags = dvpe(); |
41 | set_c0_status(0x100 << MIPS_CPU_RTLX_IRQ); |
42 | irq_enable_hazard(); |
43 | evpe(vpeflags); |
44 | local_irq_restore(flags); |
45 | |
46 | for (i = 0; i < RTLX_CHANNELS; i++) { |
47 | wake_up(&channel_wqs[i].lx_queue); |
48 | wake_up(&channel_wqs[i].rt_queue); |
49 | } |
50 | |
51 | return IRQ_HANDLED; |
52 | } |
53 | |
54 | static int rtlx_irq_num = MIPS_CPU_IRQ_BASE + MIPS_CPU_RTLX_IRQ; |
55 | |
56 | void _interrupt_sp(void) |
57 | { |
58 | unsigned long flags; |
59 | |
60 | local_irq_save(flags); |
61 | dvpe(); |
62 | settc(1); |
63 | write_vpe_c0_cause(read_vpe_c0_cause() | C_SW0); |
64 | evpe(EVPE_ENABLE); |
65 | local_irq_restore(flags); |
66 | } |
67 | |
68 | int __init rtlx_module_init(void) |
69 | { |
70 | struct device *dev; |
71 | int i, err; |
72 | |
73 | if (!cpu_has_mipsmt) { |
74 | pr_warn("VPE loader: not a MIPS MT capable processor\n" ); |
75 | return -ENODEV; |
76 | } |
77 | |
78 | if (aprp_cpu_index() == 0) { |
79 | pr_warn("No TCs reserved for AP/SP, not initializing RTLX.\n" |
80 | "Pass maxtcs=<n> argument as kernel argument\n" ); |
81 | |
82 | return -ENODEV; |
83 | } |
84 | |
85 | major = register_chrdev(major: 0, name: RTLX_MODULE_NAME, fops: &rtlx_fops); |
86 | if (major < 0) { |
87 | pr_err("rtlx_module_init: unable to register device\n" ); |
88 | return major; |
89 | } |
90 | |
91 | /* initialise the wait queues */ |
92 | for (i = 0; i < RTLX_CHANNELS; i++) { |
93 | init_waitqueue_head(&channel_wqs[i].rt_queue); |
94 | init_waitqueue_head(&channel_wqs[i].lx_queue); |
95 | atomic_set(&channel_wqs[i].in_open, 0); |
96 | mutex_init(&channel_wqs[i].mutex); |
97 | |
98 | dev = device_create(cls: mt_class, NULL, MKDEV(major, i), NULL, |
99 | fmt: "%s%d" , RTLX_MODULE_NAME, i); |
100 | if (IS_ERR(ptr: dev)) { |
101 | while (i--) |
102 | device_destroy(cls: mt_class, MKDEV(major, i)); |
103 | |
104 | err = PTR_ERR(ptr: dev); |
105 | goto out_chrdev; |
106 | } |
107 | } |
108 | |
109 | /* set up notifiers */ |
110 | rtlx_notify.start = rtlx_starting; |
111 | rtlx_notify.stop = rtlx_stopping; |
112 | vpe_notify(aprp_cpu_index(), &rtlx_notify); |
113 | |
114 | if (cpu_has_vint) { |
115 | aprp_hook = rtlx_dispatch; |
116 | } else { |
117 | pr_err("APRP RTLX init on non-vectored-interrupt processor\n" ); |
118 | err = -ENODEV; |
119 | goto out_class; |
120 | } |
121 | |
122 | err = request_irq(irq: rtlx_irq_num, handler: rtlx_interrupt, flags: 0, name: "RTLX" , dev: rtlx); |
123 | if (err) |
124 | goto out_class; |
125 | |
126 | return 0; |
127 | |
128 | out_class: |
129 | for (i = 0; i < RTLX_CHANNELS; i++) |
130 | device_destroy(cls: mt_class, MKDEV(major, i)); |
131 | out_chrdev: |
132 | unregister_chrdev(major, RTLX_MODULE_NAME); |
133 | |
134 | return err; |
135 | } |
136 | |
137 | void __exit rtlx_module_exit(void) |
138 | { |
139 | int i; |
140 | |
141 | for (i = 0; i < RTLX_CHANNELS; i++) |
142 | device_destroy(mt_class, MKDEV(major, i)); |
143 | |
144 | unregister_chrdev(major, RTLX_MODULE_NAME); |
145 | |
146 | aprp_hook = NULL; |
147 | } |
148 | |