1 /*
2  * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved.
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 as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License along
15  * with this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/init.h>
21 #include <linux/irq.h>
22 #include <linux/io.h>
23 
24 #include <mach/mxs.h>
25 #include <mach/common.h>
26 
27 #define HW_ICOLL_VECTOR				0x0000
28 #define HW_ICOLL_LEVELACK			0x0010
29 #define HW_ICOLL_CTRL				0x0020
30 #define HW_ICOLL_INTERRUPTn_SET(n)		(0x0124 + (n) * 0x10)
31 #define HW_ICOLL_INTERRUPTn_CLR(n)		(0x0128 + (n) * 0x10)
32 #define BM_ICOLL_INTERRUPTn_ENABLE		0x00000004
33 #define BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0	0x1
34 
35 static void __iomem *icoll_base = MXS_IO_ADDRESS(MXS_ICOLL_BASE_ADDR);
36 
icoll_ack_irq(struct irq_data * d)37 static void icoll_ack_irq(struct irq_data *d)
38 {
39 	/*
40 	 * The Interrupt Collector is able to prioritize irqs.
41 	 * Currently only level 0 is used. So acking can use
42 	 * BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0 unconditionally.
43 	 */
44 	__raw_writel(BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0,
45 			icoll_base + HW_ICOLL_LEVELACK);
46 }
47 
icoll_mask_irq(struct irq_data * d)48 static void icoll_mask_irq(struct irq_data *d)
49 {
50 	__raw_writel(BM_ICOLL_INTERRUPTn_ENABLE,
51 			icoll_base + HW_ICOLL_INTERRUPTn_CLR(d->irq));
52 }
53 
icoll_unmask_irq(struct irq_data * d)54 static void icoll_unmask_irq(struct irq_data *d)
55 {
56 	__raw_writel(BM_ICOLL_INTERRUPTn_ENABLE,
57 			icoll_base + HW_ICOLL_INTERRUPTn_SET(d->irq));
58 }
59 
60 static struct irq_chip mxs_icoll_chip = {
61 	.irq_ack = icoll_ack_irq,
62 	.irq_mask = icoll_mask_irq,
63 	.irq_unmask = icoll_unmask_irq,
64 };
65 
icoll_init_irq(void)66 void __init icoll_init_irq(void)
67 {
68 	int i;
69 
70 	/*
71 	 * Interrupt Collector reset, which initializes the priority
72 	 * for each irq to level 0.
73 	 */
74 	mxs_reset_block(icoll_base + HW_ICOLL_CTRL);
75 
76 	for (i = 0; i < MXS_INTERNAL_IRQS; i++) {
77 		irq_set_chip_and_handler(i, &mxs_icoll_chip, handle_level_irq);
78 		set_irq_flags(i, IRQF_VALID);
79 	}
80 }
81