xref: /openbmc/linux/arch/m68k/amiga/amiints.c (revision 93dc544c)
1 /*
2  * linux/arch/m68k/amiga/amiints.c -- Amiga Linux 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  * 11/07/96: rewritten interrupt handling, irq lists are exists now only for
9  *           this sources where it makes sense (VERTB/PORTS/EXTER) and you must
10  *           be careful that dev_id for this sources is unique since this the
11  *           only possibility to distinguish between different handlers for
12  *           free_irq. irq lists also have different irq flags:
13  *           - IRQ_FLG_FAST: handler is inserted at top of list (after other
14  *                           fast handlers)
15  *           - IRQ_FLG_SLOW: handler is inserted at bottom of list and before
16  *                           they're executed irq level is set to the previous
17  *                           one, but handlers don't need to be reentrant, if
18  *                           reentrance occurred, slow handlers will be just
19  *                           called again.
20  *           The whole interrupt handling for CIAs is moved to cia.c
21  *           /Roman Zippel
22  *
23  * 07/08/99: rewamp of the interrupt handling - we now have two types of
24  *           interrupts, normal and fast handlers, fast handlers being
25  *           marked with IRQF_DISABLED and runs with all other interrupts
26  *           disabled. Normal interrupts disable their own source but
27  *           run with all other interrupt sources enabled.
28  *           PORTS and EXTER interrupts are always shared even if the
29  *           drivers do not explicitly mark this when calling
30  *           request_irq which they really should do.
31  *           This is similar to the way interrupts are handled on all
32  *           other architectures and makes a ton of sense besides
33  *           having the advantage of making it easier to share
34  *           drivers.
35  *           /Jes
36  */
37 
38 #include <linux/init.h>
39 #include <linux/interrupt.h>
40 #include <linux/errno.h>
41 
42 #include <asm/irq.h>
43 #include <asm/traps.h>
44 #include <asm/amigahw.h>
45 #include <asm/amigaints.h>
46 #include <asm/amipcmcia.h>
47 
48 static void amiga_enable_irq(unsigned int irq);
49 static void amiga_disable_irq(unsigned int irq);
50 static irqreturn_t ami_int1(int irq, void *dev_id);
51 static irqreturn_t ami_int3(int irq, void *dev_id);
52 static irqreturn_t ami_int4(int irq, void *dev_id);
53 static irqreturn_t ami_int5(int irq, void *dev_id);
54 
55 static struct irq_controller amiga_irq_controller = {
56 	.name		= "amiga",
57 	.lock		= __SPIN_LOCK_UNLOCKED(amiga_irq_controller.lock),
58 	.enable		= amiga_enable_irq,
59 	.disable	= amiga_disable_irq,
60 };
61 
62 /*
63  * void amiga_init_IRQ(void)
64  *
65  * Parameters:	None
66  *
67  * Returns:	Nothing
68  *
69  * This function should be called during kernel startup to initialize
70  * the amiga IRQ handling routines.
71  */
72 
73 void __init amiga_init_IRQ(void)
74 {
75 	request_irq(IRQ_AUTO_1, ami_int1, 0, "int1", NULL);
76 	request_irq(IRQ_AUTO_3, ami_int3, 0, "int3", NULL);
77 	request_irq(IRQ_AUTO_4, ami_int4, 0, "int4", NULL);
78 	request_irq(IRQ_AUTO_5, ami_int5, 0, "int5", NULL);
79 
80 	m68k_setup_irq_controller(&amiga_irq_controller, IRQ_USER, AMI_STD_IRQS);
81 
82 	/* turn off PCMCIA interrupts */
83 	if (AMIGAHW_PRESENT(PCMCIA))
84 		gayle.inten = GAYLE_IRQ_IDE;
85 
86 	/* turn off all interrupts and enable the master interrupt bit */
87 	amiga_custom.intena = 0x7fff;
88 	amiga_custom.intreq = 0x7fff;
89 	amiga_custom.intena = IF_SETCLR | IF_INTEN;
90 
91 	cia_init_IRQ(&ciaa_base);
92 	cia_init_IRQ(&ciab_base);
93 }
94 
95 /*
96  * Enable/disable a particular machine specific interrupt source.
97  * Note that this may affect other interrupts in case of a shared interrupt.
98  * This function should only be called for a _very_ short time to change some
99  * internal data, that may not be changed by the interrupt at the same time.
100  */
101 
102 static void amiga_enable_irq(unsigned int irq)
103 {
104 	amiga_custom.intena = IF_SETCLR | (1 << (irq - IRQ_USER));
105 }
106 
107 static void amiga_disable_irq(unsigned int irq)
108 {
109 	amiga_custom.intena = 1 << (irq - IRQ_USER);
110 }
111 
112 /*
113  * The builtin Amiga hardware interrupt handlers.
114  */
115 
116 static irqreturn_t ami_int1(int irq, void *dev_id)
117 {
118 	unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;
119 
120 	/* if serial transmit buffer empty, interrupt */
121 	if (ints & IF_TBE) {
122 		amiga_custom.intreq = IF_TBE;
123 		m68k_handle_int(IRQ_AMIGA_TBE);
124 	}
125 
126 	/* if floppy disk transfer complete, interrupt */
127 	if (ints & IF_DSKBLK) {
128 		amiga_custom.intreq = IF_DSKBLK;
129 		m68k_handle_int(IRQ_AMIGA_DSKBLK);
130 	}
131 
132 	/* if software interrupt set, interrupt */
133 	if (ints & IF_SOFT) {
134 		amiga_custom.intreq = IF_SOFT;
135 		m68k_handle_int(IRQ_AMIGA_SOFT);
136 	}
137 	return IRQ_HANDLED;
138 }
139 
140 static irqreturn_t ami_int3(int irq, void *dev_id)
141 {
142 	unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;
143 
144 	/* if a blitter interrupt */
145 	if (ints & IF_BLIT) {
146 		amiga_custom.intreq = IF_BLIT;
147 		m68k_handle_int(IRQ_AMIGA_BLIT);
148 	}
149 
150 	/* if a copper interrupt */
151 	if (ints & IF_COPER) {
152 		amiga_custom.intreq = IF_COPER;
153 		m68k_handle_int(IRQ_AMIGA_COPPER);
154 	}
155 
156 	/* if a vertical blank interrupt */
157 	if (ints & IF_VERTB) {
158 		amiga_custom.intreq = IF_VERTB;
159 		m68k_handle_int(IRQ_AMIGA_VERTB);
160 	}
161 	return IRQ_HANDLED;
162 }
163 
164 static irqreturn_t ami_int4(int irq, void *dev_id)
165 {
166 	unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;
167 
168 	/* if audio 0 interrupt */
169 	if (ints & IF_AUD0) {
170 		amiga_custom.intreq = IF_AUD0;
171 		m68k_handle_int(IRQ_AMIGA_AUD0);
172 	}
173 
174 	/* if audio 1 interrupt */
175 	if (ints & IF_AUD1) {
176 		amiga_custom.intreq = IF_AUD1;
177 		m68k_handle_int(IRQ_AMIGA_AUD1);
178 	}
179 
180 	/* if audio 2 interrupt */
181 	if (ints & IF_AUD2) {
182 		amiga_custom.intreq = IF_AUD2;
183 		m68k_handle_int(IRQ_AMIGA_AUD2);
184 	}
185 
186 	/* if audio 3 interrupt */
187 	if (ints & IF_AUD3) {
188 		amiga_custom.intreq = IF_AUD3;
189 		m68k_handle_int(IRQ_AMIGA_AUD3);
190 	}
191 	return IRQ_HANDLED;
192 }
193 
194 static irqreturn_t ami_int5(int irq, void *dev_id)
195 {
196 	unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;
197 
198 	/* if serial receive buffer full interrupt */
199 	if (ints & IF_RBF) {
200 		/* acknowledge of IF_RBF must be done by the serial interrupt */
201 		m68k_handle_int(IRQ_AMIGA_RBF);
202 	}
203 
204 	/* if a disk sync interrupt */
205 	if (ints & IF_DSKSYN) {
206 		amiga_custom.intreq = IF_DSKSYN;
207 		m68k_handle_int(IRQ_AMIGA_DSKSYN);
208 	}
209 	return IRQ_HANDLED;
210 }
211