1 /*
2  * arch/arm/mach-mv78xx0/irq.c
3  *
4  * MV78xx0 IRQ handling.
5  *
6  * This file is licensed under the terms of the GNU General Public
7  * License version 2.  This program is licensed "as is" without any
8  * warranty of any kind, whether express or implied.
9  */
10 #include <linux/gpio.h>
11 #include <linux/kernel.h>
12 #include <linux/irq.h>
13 #include <linux/io.h>
14 #include <asm/exception.h>
15 #include <plat/orion-gpio.h>
16 #include <plat/irq.h>
17 #include "bridge-regs.h"
18 #include "common.h"
19 
20 static int __initdata gpio0_irqs[4] = {
21 	IRQ_MV78XX0_GPIO_0_7,
22 	IRQ_MV78XX0_GPIO_8_15,
23 	IRQ_MV78XX0_GPIO_16_23,
24 	IRQ_MV78XX0_GPIO_24_31,
25 };
26 
27 static void __iomem *mv78xx0_irq_base = IRQ_VIRT_BASE;
28 
29 static asmlinkage void
mv78xx0_legacy_handle_irq(struct pt_regs * regs)30 __exception_irq_entry mv78xx0_legacy_handle_irq(struct pt_regs *regs)
31 {
32 	u32 stat;
33 
34 	stat = readl_relaxed(mv78xx0_irq_base + IRQ_CAUSE_LOW_OFF);
35 	stat &= readl_relaxed(mv78xx0_irq_base + IRQ_MASK_LOW_OFF);
36 	if (stat) {
37 		unsigned int hwirq = __fls(stat);
38 		handle_IRQ(hwirq, regs);
39 		return;
40 	}
41 	stat = readl_relaxed(mv78xx0_irq_base + IRQ_CAUSE_HIGH_OFF);
42 	stat &= readl_relaxed(mv78xx0_irq_base + IRQ_MASK_HIGH_OFF);
43 	if (stat) {
44 		unsigned int hwirq = 32 + __fls(stat);
45 		handle_IRQ(hwirq, regs);
46 		return;
47 	}
48 	stat = readl_relaxed(mv78xx0_irq_base + IRQ_CAUSE_ERR_OFF);
49 	stat &= readl_relaxed(mv78xx0_irq_base + IRQ_MASK_ERR_OFF);
50 	if (stat) {
51 		unsigned int hwirq = 64 + __fls(stat);
52 		handle_IRQ(hwirq, regs);
53 		return;
54 	}
55 }
56 
mv78xx0_init_irq(void)57 void __init mv78xx0_init_irq(void)
58 {
59 	orion_irq_init(0, IRQ_VIRT_BASE + IRQ_MASK_LOW_OFF);
60 	orion_irq_init(32, IRQ_VIRT_BASE + IRQ_MASK_HIGH_OFF);
61 	orion_irq_init(64, IRQ_VIRT_BASE + IRQ_MASK_ERR_OFF);
62 
63 	set_handle_irq(mv78xx0_legacy_handle_irq);
64 
65 	/*
66 	 * Initialize gpiolib for GPIOs 0-31.  (The GPIO interrupt mask
67 	 * registers for core #1 are at an offset of 0x18 from those of
68 	 * core #0.)
69 	 */
70 	orion_gpio_init(NULL, 0, 32, GPIO_VIRT_BASE,
71 			mv78xx0_core_index() ? 0x18 : 0,
72 			IRQ_MV78XX0_GPIO_START, gpio0_irqs);
73 }
74