1 /*
2  * 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 
9 #include <linux/init.h>
10 #include <linux/interrupt.h>
11 #include <linux/errno.h>
12 #include <linux/irq.h>
13 
14 #include <asm/irq.h>
15 #include <asm/traps.h>
16 #include <asm/amigahw.h>
17 #include <asm/amigaints.h>
18 #include <asm/amipcmcia.h>
19 
20 
21 /*
22  * Enable/disable a particular machine specific interrupt source.
23  * Note that this may affect other interrupts in case of a shared interrupt.
24  * This function should only be called for a _very_ short time to change some
25  * internal data, that may not be changed by the interrupt at the same time.
26  */
27 
amiga_irq_enable(struct irq_data * data)28 static void amiga_irq_enable(struct irq_data *data)
29 {
30 	amiga_custom.intena = IF_SETCLR | (1 << (data->irq - IRQ_USER));
31 }
32 
amiga_irq_disable(struct irq_data * data)33 static void amiga_irq_disable(struct irq_data *data)
34 {
35 	amiga_custom.intena = 1 << (data->irq - IRQ_USER);
36 }
37 
38 static struct irq_chip amiga_irq_chip = {
39 	.name		= "amiga",
40 	.irq_enable	= amiga_irq_enable,
41 	.irq_disable	= amiga_irq_disable,
42 };
43 
44 
45 /*
46  * The builtin Amiga hardware interrupt handlers.
47  */
48 
ami_int1(struct irq_desc * desc)49 static void ami_int1(struct irq_desc *desc)
50 {
51 	unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;
52 
53 	/* if serial transmit buffer empty, interrupt */
54 	if (ints & IF_TBE) {
55 		amiga_custom.intreq = IF_TBE;
56 		generic_handle_irq(IRQ_AMIGA_TBE);
57 	}
58 
59 	/* if floppy disk transfer complete, interrupt */
60 	if (ints & IF_DSKBLK) {
61 		amiga_custom.intreq = IF_DSKBLK;
62 		generic_handle_irq(IRQ_AMIGA_DSKBLK);
63 	}
64 
65 	/* if software interrupt set, interrupt */
66 	if (ints & IF_SOFT) {
67 		amiga_custom.intreq = IF_SOFT;
68 		generic_handle_irq(IRQ_AMIGA_SOFT);
69 	}
70 }
71 
ami_int3(struct irq_desc * desc)72 static void ami_int3(struct irq_desc *desc)
73 {
74 	unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;
75 
76 	/* if a blitter interrupt */
77 	if (ints & IF_BLIT) {
78 		amiga_custom.intreq = IF_BLIT;
79 		generic_handle_irq(IRQ_AMIGA_BLIT);
80 	}
81 
82 	/* if a copper interrupt */
83 	if (ints & IF_COPER) {
84 		amiga_custom.intreq = IF_COPER;
85 		generic_handle_irq(IRQ_AMIGA_COPPER);
86 	}
87 
88 	/* if a vertical blank interrupt */
89 	if (ints & IF_VERTB) {
90 		amiga_custom.intreq = IF_VERTB;
91 		generic_handle_irq(IRQ_AMIGA_VERTB);
92 	}
93 }
94 
ami_int4(struct irq_desc * desc)95 static void ami_int4(struct irq_desc *desc)
96 {
97 	unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;
98 
99 	/* if audio 0 interrupt */
100 	if (ints & IF_AUD0) {
101 		amiga_custom.intreq = IF_AUD0;
102 		generic_handle_irq(IRQ_AMIGA_AUD0);
103 	}
104 
105 	/* if audio 1 interrupt */
106 	if (ints & IF_AUD1) {
107 		amiga_custom.intreq = IF_AUD1;
108 		generic_handle_irq(IRQ_AMIGA_AUD1);
109 	}
110 
111 	/* if audio 2 interrupt */
112 	if (ints & IF_AUD2) {
113 		amiga_custom.intreq = IF_AUD2;
114 		generic_handle_irq(IRQ_AMIGA_AUD2);
115 	}
116 
117 	/* if audio 3 interrupt */
118 	if (ints & IF_AUD3) {
119 		amiga_custom.intreq = IF_AUD3;
120 		generic_handle_irq(IRQ_AMIGA_AUD3);
121 	}
122 }
123 
ami_int5(struct irq_desc * desc)124 static void ami_int5(struct irq_desc *desc)
125 {
126 	unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;
127 
128 	/* if serial receive buffer full interrupt */
129 	if (ints & IF_RBF) {
130 		/* acknowledge of IF_RBF must be done by the serial interrupt */
131 		generic_handle_irq(IRQ_AMIGA_RBF);
132 	}
133 
134 	/* if a disk sync interrupt */
135 	if (ints & IF_DSKSYN) {
136 		amiga_custom.intreq = IF_DSKSYN;
137 		generic_handle_irq(IRQ_AMIGA_DSKSYN);
138 	}
139 }
140 
141 
142 /*
143  * void amiga_init_IRQ(void)
144  *
145  * Parameters:	None
146  *
147  * Returns:	Nothing
148  *
149  * This function should be called during kernel startup to initialize
150  * the amiga IRQ handling routines.
151  */
152 
amiga_init_IRQ(void)153 void __init amiga_init_IRQ(void)
154 {
155 	m68k_setup_irq_controller(&amiga_irq_chip, handle_simple_irq, IRQ_USER,
156 				  AMI_STD_IRQS);
157 
158 	irq_set_chained_handler(IRQ_AUTO_1, ami_int1);
159 	irq_set_chained_handler(IRQ_AUTO_3, ami_int3);
160 	irq_set_chained_handler(IRQ_AUTO_4, ami_int4);
161 	irq_set_chained_handler(IRQ_AUTO_5, ami_int5);
162 
163 	/* turn off PCMCIA interrupts */
164 	if (AMIGAHW_PRESENT(PCMCIA))
165 		gayle.inten = GAYLE_IRQ_IDE;
166 
167 	/* turn off all interrupts and enable the master interrupt bit */
168 	amiga_custom.intena = 0x7fff;
169 	amiga_custom.intreq = 0x7fff;
170 	amiga_custom.intena = IF_SETCLR | IF_INTEN;
171 
172 	cia_init_IRQ(&ciaa_base);
173 	cia_init_IRQ(&ciab_base);
174 }
175