Eric Lee / smarc-ti-linux-kernel

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Commit 3ddd91c0c2c0b7bf024ad93b2dcce6a6dec8d366

Authored by Texas Instruments Auto Merger
2 parents 5423bfb317 d8f0925919
Exists in ti-lsk-linux-4.1.y and in 5 other branches processor-sdk-linux-02.00.01, smarc-ti-lsk-linux-4.1.y, smarct3x-processor-sdk-linux-02.00.01, smarct4x-800-processor-sdk-linux-02.00.01, smarct4x-processor-sdk-linux-02.00.01

Merge branch 'ti-linux-4.1.y' of git.ti.com:ti-linux-kernel/ti-linux-kernel into ti-lsk-linux-4.1.y 

TI-Feature: ti_linux_base_lsk
TI-Tree: git@git.ti.com:ti-linux-kernel/ti-linux-kernel.git
TI-Branch: ti-linux-4.1.y

* 'ti-linux-4.1.y' of git.ti.com:ti-linux-kernel/ti-linux-kernel:
  genirq: Export handle_bad_irq

Signed-off-by: Texas Instruments Auto Merger <lcpd_integration@list.ti.com>

Showing 1 changed file Inline Diff

1 /* 1 /*
2 * linux/kernel/irq/handle.c 2 * linux/kernel/irq/handle.c
3 * 3 *
4 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar 4 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
5 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King 5 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
6 * 6 *
7 * This file contains the core interrupt handling code. 7 * This file contains the core interrupt handling code.
8 * 8 *
9 * Detailed information is available in Documentation/DocBook/genericirq 9 * Detailed information is available in Documentation/DocBook/genericirq
10 * 10 *
11 */ 11 */
12 12
13 #include <linux/irq.h> 13 #include <linux/irq.h>
14 #include <linux/random.h> 14 #include <linux/random.h>
15 #include <linux/sched.h> 15 #include <linux/sched.h>
16 #include <linux/interrupt.h> 16 #include <linux/interrupt.h>
17 #include <linux/kernel_stat.h> 17 #include <linux/kernel_stat.h>
18 18
19 #include <trace/events/irq.h> 19 #include <trace/events/irq.h>
20 20
21 #include "internals.h" 21 #include "internals.h"
22 22
23 /** 23 /**
24 * handle_bad_irq - handle spurious and unhandled irqs 24 * handle_bad_irq - handle spurious and unhandled irqs
25 * @irq: the interrupt number 25 * @irq: the interrupt number
26 * @desc: description of the interrupt 26 * @desc: description of the interrupt
27 * 27 *
28 * Handles spurious and unhandled IRQ's. It also prints a debugmessage. 28 * Handles spurious and unhandled IRQ's. It also prints a debugmessage.
29 */ 29 */
30 void handle_bad_irq(unsigned int irq, struct irq_desc *desc) 30 void handle_bad_irq(unsigned int irq, struct irq_desc *desc)
31 { 31 {
32 print_irq_desc(irq, desc); 32 print_irq_desc(irq, desc);
33 kstat_incr_irqs_this_cpu(irq, desc); 33 kstat_incr_irqs_this_cpu(irq, desc);
34 ack_bad_irq(irq); 34 ack_bad_irq(irq);
35 } 35 }
36 EXPORT_SYMBOL_GPL(handle_bad_irq);
36 37
37 /* 38 /*
38 * Special, empty irq handler: 39 * Special, empty irq handler:
39 */ 40 */
40 irqreturn_t no_action(int cpl, void *dev_id) 41 irqreturn_t no_action(int cpl, void *dev_id)
41 { 42 {
42 return IRQ_NONE; 43 return IRQ_NONE;
43 } 44 }
44 EXPORT_SYMBOL_GPL(no_action); 45 EXPORT_SYMBOL_GPL(no_action);
45 46
46 static void warn_no_thread(unsigned int irq, struct irqaction *action) 47 static void warn_no_thread(unsigned int irq, struct irqaction *action)
47 { 48 {
48 if (test_and_set_bit(IRQTF_WARNED, &action->thread_flags)) 49 if (test_and_set_bit(IRQTF_WARNED, &action->thread_flags))
49 return; 50 return;
50 51
51 printk(KERN_WARNING "IRQ %d device %s returned IRQ_WAKE_THREAD " 52 printk(KERN_WARNING "IRQ %d device %s returned IRQ_WAKE_THREAD "
52 "but no thread function available.", irq, action->name); 53 "but no thread function available.", irq, action->name);
53 } 54 }
54 55
55 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action) 56 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action)
56 { 57 {
57 /* 58 /*
58 * In case the thread crashed and was killed we just pretend that 59 * In case the thread crashed and was killed we just pretend that
59 * we handled the interrupt. The hardirq handler has disabled the 60 * we handled the interrupt. The hardirq handler has disabled the
60 * device interrupt, so no irq storm is lurking. 61 * device interrupt, so no irq storm is lurking.
61 */ 62 */
62 if (action->thread->flags & PF_EXITING) 63 if (action->thread->flags & PF_EXITING)
63 return; 64 return;
64 65
65 /* 66 /*
66 * Wake up the handler thread for this action. If the 67 * Wake up the handler thread for this action. If the
67 * RUNTHREAD bit is already set, nothing to do. 68 * RUNTHREAD bit is already set, nothing to do.
68 */ 69 */
69 if (test_and_set_bit(IRQTF_RUNTHREAD, &action->thread_flags)) 70 if (test_and_set_bit(IRQTF_RUNTHREAD, &action->thread_flags))
70 return; 71 return;
71 72
72 /* 73 /*
73 * It's safe to OR the mask lockless here. We have only two 74 * It's safe to OR the mask lockless here. We have only two
74 * places which write to threads_oneshot: This code and the 75 * places which write to threads_oneshot: This code and the
75 * irq thread. 76 * irq thread.
76 * 77 *
77 * This code is the hard irq context and can never run on two 78 * This code is the hard irq context and can never run on two
78 * cpus in parallel. If it ever does we have more serious 79 * cpus in parallel. If it ever does we have more serious
79 * problems than this bitmask. 80 * problems than this bitmask.
80 * 81 *
81 * The irq threads of this irq which clear their "running" bit 82 * The irq threads of this irq which clear their "running" bit
82 * in threads_oneshot are serialized via desc->lock against 83 * in threads_oneshot are serialized via desc->lock against
83 * each other and they are serialized against this code by 84 * each other and they are serialized against this code by
84 * IRQS_INPROGRESS. 85 * IRQS_INPROGRESS.
85 * 86 *
86 * Hard irq handler: 87 * Hard irq handler:
87 * 88 *
88 * spin_lock(desc->lock); 89 * spin_lock(desc->lock);
89 * desc->state |= IRQS_INPROGRESS; 90 * desc->state |= IRQS_INPROGRESS;
90 * spin_unlock(desc->lock); 91 * spin_unlock(desc->lock);
91 * set_bit(IRQTF_RUNTHREAD, &action->thread_flags); 92 * set_bit(IRQTF_RUNTHREAD, &action->thread_flags);
92 * desc->threads_oneshot |= mask; 93 * desc->threads_oneshot |= mask;
93 * spin_lock(desc->lock); 94 * spin_lock(desc->lock);
94 * desc->state &= ~IRQS_INPROGRESS; 95 * desc->state &= ~IRQS_INPROGRESS;
95 * spin_unlock(desc->lock); 96 * spin_unlock(desc->lock);
96 * 97 *
97 * irq thread: 98 * irq thread:
98 * 99 *
99 * again: 100 * again:
100 * spin_lock(desc->lock); 101 * spin_lock(desc->lock);
101 * if (desc->state & IRQS_INPROGRESS) { 102 * if (desc->state & IRQS_INPROGRESS) {
102 * spin_unlock(desc->lock); 103 * spin_unlock(desc->lock);
103 * while(desc->state & IRQS_INPROGRESS) 104 * while(desc->state & IRQS_INPROGRESS)
104 * cpu_relax(); 105 * cpu_relax();
105 * goto again; 106 * goto again;
106 * } 107 * }
107 * if (!test_bit(IRQTF_RUNTHREAD, &action->thread_flags)) 108 * if (!test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
108 * desc->threads_oneshot &= ~mask; 109 * desc->threads_oneshot &= ~mask;
109 * spin_unlock(desc->lock); 110 * spin_unlock(desc->lock);
110 * 111 *
111 * So either the thread waits for us to clear IRQS_INPROGRESS 112 * So either the thread waits for us to clear IRQS_INPROGRESS
112 * or we are waiting in the flow handler for desc->lock to be 113 * or we are waiting in the flow handler for desc->lock to be
113 * released before we reach this point. The thread also checks 114 * released before we reach this point. The thread also checks
114 * IRQTF_RUNTHREAD under desc->lock. If set it leaves 115 * IRQTF_RUNTHREAD under desc->lock. If set it leaves
115 * threads_oneshot untouched and runs the thread another time. 116 * threads_oneshot untouched and runs the thread another time.
116 */ 117 */
117 desc->threads_oneshot |= action->thread_mask; 118 desc->threads_oneshot |= action->thread_mask;
118 119
119 /* 120 /*
120 * We increment the threads_active counter in case we wake up 121 * We increment the threads_active counter in case we wake up
121 * the irq thread. The irq thread decrements the counter when 122 * the irq thread. The irq thread decrements the counter when
122 * it returns from the handler or in the exit path and wakes 123 * it returns from the handler or in the exit path and wakes
123 * up waiters which are stuck in synchronize_irq() when the 124 * up waiters which are stuck in synchronize_irq() when the
124 * active count becomes zero. synchronize_irq() is serialized 125 * active count becomes zero. synchronize_irq() is serialized
125 * against this code (hard irq handler) via IRQS_INPROGRESS 126 * against this code (hard irq handler) via IRQS_INPROGRESS
126 * like the finalize_oneshot() code. See comment above. 127 * like the finalize_oneshot() code. See comment above.
127 */ 128 */
128 atomic_inc(&desc->threads_active); 129 atomic_inc(&desc->threads_active);
129 130
130 wake_up_process(action->thread); 131 wake_up_process(action->thread);
131 } 132 }
132 133
133 irqreturn_t 134 irqreturn_t
134 handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action) 135 handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action)
135 { 136 {
136 irqreturn_t retval = IRQ_NONE; 137 irqreturn_t retval = IRQ_NONE;
137 unsigned int flags = 0, irq = desc->irq_data.irq; 138 unsigned int flags = 0, irq = desc->irq_data.irq;
138 139
139 do { 140 do {
140 irqreturn_t res; 141 irqreturn_t res;
141 142
142 trace_irq_handler_entry(irq, action); 143 trace_irq_handler_entry(irq, action);
143 res = action->handler(irq, action->dev_id); 144 res = action->handler(irq, action->dev_id);
144 trace_irq_handler_exit(irq, action, res); 145 trace_irq_handler_exit(irq, action, res);
145 146
146 if (WARN_ONCE(!irqs_disabled(),"irq %u handler %pF enabled interrupts\n", 147 if (WARN_ONCE(!irqs_disabled(),"irq %u handler %pF enabled interrupts\n",
147 irq, action->handler)) 148 irq, action->handler))
148 local_irq_disable(); 149 local_irq_disable();
149 150
150 switch (res) { 151 switch (res) {
151 case IRQ_WAKE_THREAD: 152 case IRQ_WAKE_THREAD:
152 /* 153 /*
153 * Catch drivers which return WAKE_THREAD but 154 * Catch drivers which return WAKE_THREAD but
154 * did not set up a thread function 155 * did not set up a thread function
155 */ 156 */
156 if (unlikely(!action->thread_fn)) { 157 if (unlikely(!action->thread_fn)) {
157 warn_no_thread(irq, action); 158 warn_no_thread(irq, action);
158 break; 159 break;
159 } 160 }
160 161
161 __irq_wake_thread(desc, action); 162 __irq_wake_thread(desc, action);
162 163
163 /* Fall through to add to randomness */ 164 /* Fall through to add to randomness */
164 case IRQ_HANDLED: 165 case IRQ_HANDLED:
165 flags |= action->flags; 166 flags |= action->flags;
166 break; 167 break;
167 168
168 default: 169 default:
169 break; 170 break;
170 } 171 }
171 172
172 retval |= res; 173 retval |= res;
173 action = action->next; 174 action = action->next;
174 } while (action); 175 } while (action);
175 176
176 add_interrupt_randomness(irq, flags); 177 add_interrupt_randomness(irq, flags);
177 178
178 if (!noirqdebug) 179 if (!noirqdebug)
179 note_interrupt(irq, desc, retval); 180 note_interrupt(irq, desc, retval);
180 return retval; 181 return retval;
181 } 182 }
182 183
183 irqreturn_t handle_irq_event(struct irq_desc *desc) 184 irqreturn_t handle_irq_event(struct irq_desc *desc)
184 { 185 {
185 struct irqaction *action = desc->action; 186 struct irqaction *action = desc->action;
186 irqreturn_t ret; 187 irqreturn_t ret;
187 188
188 desc->istate &= ~IRQS_PENDING; 189 desc->istate &= ~IRQS_PENDING;
189 irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS); 190 irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
190 raw_spin_unlock(&desc->lock); 191 raw_spin_unlock(&desc->lock);
191 192
192 ret = handle_irq_event_percpu(desc, action); 193 ret = handle_irq_event_percpu(desc, action);
193 194
194 raw_spin_lock(&desc->lock); 195 raw_spin_lock(&desc->lock);
195 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); 196 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
196 return ret; 197 return ret;
197 } 198 }
198 199