1 /*
2  * linux/arch/m68k/kernel/ints.c -- Linux/m68k general interrupt handling code
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License.  See the file COPYING in the main directory of this archive
6  * for more details.
7  *
8  * 07/03/96: Timer initialization, and thus mach_sched_init(),
9  *           removed from request_irq() and moved to init_time().
10  *           We should therefore consider renaming our add_isr() and
11  *           remove_isr() to request_irq() and free_irq()
12  *           respectively, so they are compliant with the other
13  *           architectures.                                     /Jes
14  * 11/07/96: Changed all add_/remove_isr() to request_/free_irq() calls.
15  *           Removed irq list support, if any machine needs an irq server
16  *           it must implement this itself (as it's already done), instead
17  *           only default handler are used with mach_default_handler.
18  *           request_irq got some flags different from other architectures:
19  *           - IRQ_FLG_REPLACE : Replace an existing handler (the default one
20  *                               can be replaced without this flag)
21  *           - IRQ_FLG_LOCK : handler can't be replaced
22  *           There are other machine depending flags, see there
23  *           If you want to replace a default handler you should know what
24  *           you're doing, since it might handle different other irq sources
25  *           which must be served                               /Roman Zippel
26  */
27 
28 #include <linux/config.h>
29 #include <linux/types.h>
30 #include <linux/sched.h>
31 #include <linux/kernel_stat.h>
32 #include <linux/errno.h>
33 #include <linux/init.h>
34 
35 #include <asm/setup.h>
36 #include <asm/system.h>
37 #include <asm/irq.h>
38 #include <asm/traps.h>
39 #include <asm/page.h>
40 #include <asm/machdep.h>
41 
42 #ifdef CONFIG_Q40
43 #include <asm/q40ints.h>
44 #endif
45 
46 /* table for system interrupt handlers */
47 static irq_handler_t irq_list[SYS_IRQS];
48 
49 static const char *default_names[SYS_IRQS] = {
50 	"spurious int", "int1 handler", "int2 handler", "int3 handler",
51 	"int4 handler", "int5 handler", "int6 handler", "int7 handler"
52 };
53 
54 /* The number of spurious interrupts */
55 volatile unsigned int num_spurious;
56 
57 #define NUM_IRQ_NODES 100
58 static irq_node_t nodes[NUM_IRQ_NODES];
59 
60 static void dummy_enable_irq(unsigned int irq);
61 static void dummy_disable_irq(unsigned int irq);
62 static int dummy_request_irq(unsigned int irq,
63 		void (*handler) (int, void *, struct pt_regs *),
64 		unsigned long flags, const char *devname, void *dev_id);
65 static void dummy_free_irq(unsigned int irq, void *dev_id);
66 
67 void (*enable_irq) (unsigned int) = dummy_enable_irq;
68 void (*disable_irq) (unsigned int) = dummy_disable_irq;
69 
70 int (*mach_request_irq) (unsigned int, void (*)(int, void *, struct pt_regs *),
71                       unsigned long, const char *, void *) = dummy_request_irq;
72 void (*mach_free_irq) (unsigned int, void *) = dummy_free_irq;
73 
74 void init_irq_proc(void);
75 
76 /*
77  * void init_IRQ(void)
78  *
79  * Parameters:	None
80  *
81  * Returns:	Nothing
82  *
83  * This function should be called during kernel startup to initialize
84  * the IRQ handling routines.
85  */
86 
init_IRQ(void)87 void __init init_IRQ(void)
88 {
89 	int i;
90 
91 	for (i = 0; i < SYS_IRQS; i++) {
92 		if (mach_default_handler)
93 			irq_list[i].handler = (*mach_default_handler)[i];
94 		irq_list[i].flags   = 0;
95 		irq_list[i].dev_id  = NULL;
96 		irq_list[i].devname = default_names[i];
97 	}
98 
99 	for (i = 0; i < NUM_IRQ_NODES; i++)
100 		nodes[i].handler = NULL;
101 
102 	mach_init_IRQ ();
103 }
104 
new_irq_node(void)105 irq_node_t *new_irq_node(void)
106 {
107 	irq_node_t *node;
108 	short i;
109 
110 	for (node = nodes, i = NUM_IRQ_NODES-1; i >= 0; node++, i--)
111 		if (!node->handler)
112 			return node;
113 
114 	printk ("new_irq_node: out of nodes\n");
115 	return NULL;
116 }
117 
118 /*
119  * We will keep these functions until I have convinced Linus to move
120  * the declaration of them from include/linux/sched.h to
121  * include/asm/irq.h.
122  */
request_irq(unsigned int irq,void (* handler)(int,void *,struct pt_regs *),unsigned long flags,const char * devname,void * dev_id)123 int request_irq(unsigned int irq,
124 		void (*handler) (int, void *, struct pt_regs *),
125 		unsigned long flags, const char *devname, void *dev_id)
126 {
127 	return mach_request_irq(irq, handler, flags, devname, dev_id);
128 }
129 
free_irq(unsigned int irq,void * dev_id)130 void free_irq(unsigned int irq, void *dev_id)
131 {
132 	mach_free_irq(irq, dev_id);
133 }
134 
sys_request_irq(unsigned int irq,void (* handler)(int,void *,struct pt_regs *),unsigned long flags,const char * devname,void * dev_id)135 int sys_request_irq(unsigned int irq,
136                     void (*handler)(int, void *, struct pt_regs *),
137                     unsigned long flags, const char *devname, void *dev_id)
138 {
139 	if (irq < IRQ1 || irq > IRQ7) {
140 		printk("%s: Incorrect IRQ %d from %s\n",
141 		       __FUNCTION__, irq, devname);
142 		return -ENXIO;
143 	}
144 
145 #if 0
146 	if (!(irq_list[irq].flags & IRQ_FLG_STD)) {
147 		if (irq_list[irq].flags & IRQ_FLG_LOCK) {
148 			printk("%s: IRQ %d from %s is not replaceable\n",
149 			       __FUNCTION__, irq, irq_list[irq].devname);
150 			return -EBUSY;
151 		}
152 		if (!(flags & IRQ_FLG_REPLACE)) {
153 			printk("%s: %s can't replace IRQ %d from %s\n",
154 			       __FUNCTION__, devname, irq, irq_list[irq].devname);
155 			return -EBUSY;
156 		}
157 	}
158 #endif
159 
160 	irq_list[irq].handler = handler;
161 	irq_list[irq].flags   = flags;
162 	irq_list[irq].dev_id  = dev_id;
163 	irq_list[irq].devname = devname;
164 	return 0;
165 }
166 
sys_free_irq(unsigned int irq,void * dev_id)167 void sys_free_irq(unsigned int irq, void *dev_id)
168 {
169 	if (irq < IRQ1 || irq > IRQ7) {
170 		printk("%s: Incorrect IRQ %d\n", __FUNCTION__, irq);
171 		return;
172 	}
173 
174 	if (irq_list[irq].dev_id != dev_id)
175 		printk("%s: Removing probably wrong IRQ %d from %s\n",
176 		       __FUNCTION__, irq, irq_list[irq].devname);
177 
178 	irq_list[irq].handler = (*mach_default_handler)[irq];
179 	irq_list[irq].flags   = 0;
180 	irq_list[irq].dev_id  = NULL;
181 	irq_list[irq].devname = default_names[irq];
182 }
183 
184 /*
185  * Do we need these probe functions on the m68k?
186  *
187  *  ... may be useful with ISA devices
188  */
probe_irq_on(void)189 unsigned long probe_irq_on (void)
190 {
191 #ifdef CONFIG_Q40
192 	if (MACH_IS_Q40)
193 		return q40_probe_irq_on();
194 #endif
195 	return 0;
196 }
197 
probe_irq_off(unsigned long irqs)198 int probe_irq_off (unsigned long irqs)
199 {
200 #ifdef CONFIG_Q40
201 	if (MACH_IS_Q40)
202 		return q40_probe_irq_off(irqs);
203 #endif
204 	return 0;
205 }
206 
dummy_enable_irq(unsigned int irq)207 static void dummy_enable_irq(unsigned int irq)
208 {
209 	printk("calling uninitialized enable_irq()\n");
210 }
211 
dummy_disable_irq(unsigned int irq)212 static void dummy_disable_irq(unsigned int irq)
213 {
214 	printk("calling uninitialized disable_irq()\n");
215 }
216 
dummy_request_irq(unsigned int irq,void (* handler)(int,void *,struct pt_regs *),unsigned long flags,const char * devname,void * dev_id)217 static int dummy_request_irq(unsigned int irq,
218 		void (*handler) (int, void *, struct pt_regs *),
219 		unsigned long flags, const char *devname, void *dev_id)
220 {
221 	printk("calling uninitialized request_irq()\n");
222 	return 0;
223 }
224 
dummy_free_irq(unsigned int irq,void * dev_id)225 static void dummy_free_irq(unsigned int irq, void *dev_id)
226 {
227 	printk("calling uninitialized disable_irq()\n");
228 }
229 
process_int(unsigned long vec,struct pt_regs * fp)230 asmlinkage void process_int(unsigned long vec, struct pt_regs *fp)
231 {
232 	if (vec >= VEC_INT1 && vec <= VEC_INT7 && !MACH_IS_BVME6000) {
233 		vec -= VEC_SPUR;
234 		kstat.irqs[0][vec]++;
235 		irq_list[vec].handler(vec, irq_list[vec].dev_id, fp);
236 	} else {
237 		if (mach_process_int)
238 			mach_process_int(vec, fp);
239 		else
240 			panic("Can't process interrupt vector %ld\n", vec);
241 		return;
242 	}
243 }
244 
get_irq_list(char * buf)245 int get_irq_list(char *buf)
246 {
247 	int i, len = 0;
248 
249 	/* autovector interrupts */
250 	if (mach_default_handler) {
251 		for (i = 0; i < SYS_IRQS; i++) {
252 			len += sprintf(buf+len, "auto %2d: %10u ", i,
253 			               i ? kstat.irqs[0][i] : num_spurious);
254 				len += sprintf(buf+len, "  ");
255 			len += sprintf(buf+len, "%s\n", irq_list[i].devname);
256 		}
257 	}
258 
259 	len += mach_get_irq_list(buf+len);
260 	return len;
261 }
262 
init_irq_proc(void)263 void init_irq_proc(void)
264 {
265 	/* Insert /proc/irq driver here */
266 }
267 
268