avr32: Rename at32ap.c -> pdc.c
[linux-2.6.git] / arch / avr32 / mach-at32ap / intc.c
1 /*
2  * Copyright (C) 2006 Atmel Corporation
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8
9 #include <linux/clk.h>
10 #include <linux/err.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/irq.h>
14 #include <linux/platform_device.h>
15
16 #include <asm/io.h>
17
18 #include "intc.h"
19
20 struct intc {
21         void __iomem    *regs;
22         struct irq_chip chip;
23 };
24
25 extern struct platform_device at32_intc0_device;
26
27 /*
28  * TODO: We may be able to implement mask/unmask by setting IxM flags
29  * in the status register.
30  */
31 static void intc_mask_irq(unsigned int irq)
32 {
33
34 }
35
36 static void intc_unmask_irq(unsigned int irq)
37 {
38
39 }
40
41 static struct intc intc0 = {
42         .chip = {
43                 .name           = "intc",
44                 .mask           = intc_mask_irq,
45                 .unmask         = intc_unmask_irq,
46         },
47 };
48
49 /*
50  * All interrupts go via intc at some point.
51  */
52 asmlinkage void do_IRQ(int level, struct pt_regs *regs)
53 {
54         struct irq_desc *desc;
55         struct pt_regs *old_regs;
56         unsigned int irq;
57         unsigned long status_reg;
58
59         local_irq_disable();
60
61         old_regs = set_irq_regs(regs);
62
63         irq_enter();
64
65         irq = intc_readl(&intc0, INTCAUSE0 - 4 * level);
66         desc = irq_desc + irq;
67         desc->handle_irq(irq, desc);
68
69         /*
70          * Clear all interrupt level masks so that we may handle
71          * interrupts during softirq processing.  If this is a nested
72          * interrupt, interrupts must stay globally disabled until we
73          * return.
74          */
75         status_reg = sysreg_read(SR);
76         status_reg &= ~(SYSREG_BIT(I0M) | SYSREG_BIT(I1M)
77                         | SYSREG_BIT(I2M) | SYSREG_BIT(I3M));
78         sysreg_write(SR, status_reg);
79
80         irq_exit();
81
82         set_irq_regs(old_regs);
83 }
84
85 void __init init_IRQ(void)
86 {
87         extern void _evba(void);
88         extern void irq_level0(void);
89         struct resource *regs;
90         struct clk *pclk;
91         unsigned int i;
92         u32 offset, readback;
93
94         regs = platform_get_resource(&at32_intc0_device, IORESOURCE_MEM, 0);
95         if (!regs) {
96                 printk(KERN_EMERG "intc: no mmio resource defined\n");
97                 goto fail;
98         }
99         pclk = clk_get(&at32_intc0_device.dev, "pclk");
100         if (IS_ERR(pclk)) {
101                 printk(KERN_EMERG "intc: no clock defined\n");
102                 goto fail;
103         }
104
105         clk_enable(pclk);
106
107         intc0.regs = ioremap(regs->start, regs->end - regs->start + 1);
108         if (!intc0.regs) {
109                 printk(KERN_EMERG "intc: failed to map registers (0x%08lx)\n",
110                        (unsigned long)regs->start);
111                 goto fail;
112         }
113
114         /*
115          * Initialize all interrupts to level 0 (lowest priority). The
116          * priority level may be changed by calling
117          * irq_set_priority().
118          *
119          */
120         offset = (unsigned long)&irq_level0 - (unsigned long)&_evba;
121         for (i = 0; i < NR_INTERNAL_IRQS; i++) {
122                 intc_writel(&intc0, INTPR0 + 4 * i, offset);
123                 readback = intc_readl(&intc0, INTPR0 + 4 * i);
124                 if (readback == offset)
125                         set_irq_chip_and_handler(i, &intc0.chip,
126                                                  handle_simple_irq);
127         }
128
129         /* Unmask all interrupt levels */
130         sysreg_write(SR, (sysreg_read(SR)
131                           & ~(SR_I3M | SR_I2M | SR_I1M | SR_I0M)));
132
133         return;
134
135 fail:
136         panic("Interrupt controller initialization failed!\n");
137 }
138
139 unsigned long intc_get_pending(unsigned int group)
140 {
141         return intc_readl(&intc0, INTREQ0 + 4 * group);
142 }
143 EXPORT_SYMBOL_GPL(intc_get_pending);