1 /*
2  * Interrupt handler for DaVinci boards.
3  *
4  * Copyright (C) 2006 Texas Instruments.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19  *
20  */
21 #include <linux/kernel.h>
22 #include <linux/init.h>
23 #include <linux/interrupt.h>
24 #include <linux/irq.h>
25 #include <linux/io.h>
26 
27 #include <mach/hardware.h>
28 #include <mach/cputype.h>
29 #include <mach/common.h>
30 #include <asm/mach/irq.h>
31 
32 #define FIQ_REG0_OFFSET		0x0000
33 #define FIQ_REG1_OFFSET		0x0004
34 #define IRQ_REG0_OFFSET		0x0008
35 #define IRQ_REG1_OFFSET		0x000C
36 #define IRQ_ENT_REG0_OFFSET	0x0018
37 #define IRQ_ENT_REG1_OFFSET	0x001C
38 #define IRQ_INCTL_REG_OFFSET	0x0020
39 #define IRQ_EABASE_REG_OFFSET	0x0024
40 #define IRQ_INTPRI0_REG_OFFSET	0x0030
41 #define IRQ_INTPRI7_REG_OFFSET	0x004C
42 
davinci_irq_writel(unsigned long value,int offset)43 static inline void davinci_irq_writel(unsigned long value, int offset)
44 {
45 	__raw_writel(value, davinci_intc_base + offset);
46 }
47 
48 static __init void
davinci_alloc_gc(void __iomem * base,unsigned int irq_start,unsigned int num)49 davinci_alloc_gc(void __iomem *base, unsigned int irq_start, unsigned int num)
50 {
51 	struct irq_chip_generic *gc;
52 	struct irq_chip_type *ct;
53 
54 	gc = irq_alloc_generic_chip("AINTC", 1, irq_start, base, handle_edge_irq);
55 	if (!gc) {
56 		pr_err("%s: irq_alloc_generic_chip for IRQ %u failed\n",
57 		       __func__, irq_start);
58 		return;
59 	}
60 
61 	ct = gc->chip_types;
62 	ct->chip.irq_ack = irq_gc_ack_set_bit;
63 	ct->chip.irq_mask = irq_gc_mask_clr_bit;
64 	ct->chip.irq_unmask = irq_gc_mask_set_bit;
65 
66 	ct->regs.ack = IRQ_REG0_OFFSET;
67 	ct->regs.mask = IRQ_ENT_REG0_OFFSET;
68 	irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
69 			       IRQ_NOREQUEST | IRQ_NOPROBE, 0);
70 }
71 
72 /* ARM Interrupt Controller Initialization */
davinci_irq_init(void)73 void __init davinci_irq_init(void)
74 {
75 	unsigned i, j;
76 	const u8 *davinci_def_priorities = davinci_soc_info.intc_irq_prios;
77 
78 	davinci_intc_type = DAVINCI_INTC_TYPE_AINTC;
79 	davinci_intc_base = ioremap(davinci_soc_info.intc_base, SZ_4K);
80 	if (WARN_ON(!davinci_intc_base))
81 		return;
82 
83 	/* Clear all interrupt requests */
84 	davinci_irq_writel(~0x0, FIQ_REG0_OFFSET);
85 	davinci_irq_writel(~0x0, FIQ_REG1_OFFSET);
86 	davinci_irq_writel(~0x0, IRQ_REG0_OFFSET);
87 	davinci_irq_writel(~0x0, IRQ_REG1_OFFSET);
88 
89 	/* Disable all interrupts */
90 	davinci_irq_writel(0x0, IRQ_ENT_REG0_OFFSET);
91 	davinci_irq_writel(0x0, IRQ_ENT_REG1_OFFSET);
92 
93 	/* Interrupts disabled immediately, IRQ entry reflects all */
94 	davinci_irq_writel(0x0, IRQ_INCTL_REG_OFFSET);
95 
96 	/* we don't use the hardware vector table, just its entry addresses */
97 	davinci_irq_writel(0, IRQ_EABASE_REG_OFFSET);
98 
99 	/* Clear all interrupt requests */
100 	davinci_irq_writel(~0x0, FIQ_REG0_OFFSET);
101 	davinci_irq_writel(~0x0, FIQ_REG1_OFFSET);
102 	davinci_irq_writel(~0x0, IRQ_REG0_OFFSET);
103 	davinci_irq_writel(~0x0, IRQ_REG1_OFFSET);
104 
105 	for (i = IRQ_INTPRI0_REG_OFFSET; i <= IRQ_INTPRI7_REG_OFFSET; i += 4) {
106 		u32		pri;
107 
108 		for (j = 0, pri = 0; j < 32; j += 4, davinci_def_priorities++)
109 			pri |= (*davinci_def_priorities & 0x07) << j;
110 		davinci_irq_writel(pri, i);
111 	}
112 
113 	for (i = 0, j = 0; i < davinci_soc_info.intc_irq_num; i += 32, j += 0x04)
114 		davinci_alloc_gc(davinci_intc_base + j, i, 32);
115 
116 	irq_set_handler(IRQ_TINT1_TINT34, handle_level_irq);
117 }
118