1/*
2 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
3 * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version 2
8 * of the License, or (at your option) any later version.
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
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
17 * MA  02110-1301, USA.
18 */
19
20#include <linux/module.h>
21#include <linux/irq.h>
22#include <linux/irqdomain.h>
23#include <linux/io.h>
24#include <linux/of.h>
25#include <asm/mach/irq.h>
26#include <asm/exception.h>
27
28#include "common.h"
29#include "hardware.h"
30#include "irq-common.h"
31
32#define AVIC_INTCNTL		0x00	/* int control reg */
33#define AVIC_NIMASK		0x04	/* int mask reg */
34#define AVIC_INTENNUM		0x08	/* int enable number reg */
35#define AVIC_INTDISNUM		0x0C	/* int disable number reg */
36#define AVIC_INTENABLEH		0x10	/* int enable reg high */
37#define AVIC_INTENABLEL		0x14	/* int enable reg low */
38#define AVIC_INTTYPEH		0x18	/* int type reg high */
39#define AVIC_INTTYPEL		0x1C	/* int type reg low */
40#define AVIC_NIPRIORITY(x)	(0x20 + 4 * (7 - (x))) /* int priority */
41#define AVIC_NIVECSR		0x40	/* norm int vector/status */
42#define AVIC_FIVECSR		0x44	/* fast int vector/status */
43#define AVIC_INTSRCH		0x48	/* int source reg high */
44#define AVIC_INTSRCL		0x4C	/* int source reg low */
45#define AVIC_INTFRCH		0x50	/* int force reg high */
46#define AVIC_INTFRCL		0x54	/* int force reg low */
47#define AVIC_NIPNDH		0x58	/* norm int pending high */
48#define AVIC_NIPNDL		0x5C	/* norm int pending low */
49#define AVIC_FIPNDH		0x60	/* fast int pending high */
50#define AVIC_FIPNDL		0x64	/* fast int pending low */
51
52#define AVIC_NUM_IRQS 64
53
54static void __iomem *avic_base;
55static struct irq_domain *domain;
56
57#ifdef CONFIG_FIQ
58static int avic_set_irq_fiq(unsigned int irq, unsigned int type)
59{
60	struct irq_data *d = irq_get_irq_data(irq);
61	unsigned int irqt;
62
63	irq = d->hwirq;
64
65	if (irq >= AVIC_NUM_IRQS)
66		return -EINVAL;
67
68	if (irq < AVIC_NUM_IRQS / 2) {
69		irqt = __raw_readl(avic_base + AVIC_INTTYPEL) & ~(1 << irq);
70		__raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEL);
71	} else {
72		irq -= AVIC_NUM_IRQS / 2;
73		irqt = __raw_readl(avic_base + AVIC_INTTYPEH) & ~(1 << irq);
74		__raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEH);
75	}
76
77	return 0;
78}
79#endif /* CONFIG_FIQ */
80
81
82static struct mxc_extra_irq avic_extra_irq = {
83#ifdef CONFIG_FIQ
84	.set_irq_fiq = avic_set_irq_fiq,
85#endif
86};
87
88#ifdef CONFIG_PM
89static u32 avic_saved_mask_reg[2];
90
91static void avic_irq_suspend(struct irq_data *d)
92{
93	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
94	struct irq_chip_type *ct = gc->chip_types;
95	int idx = d->hwirq >> 5;
96
97	avic_saved_mask_reg[idx] = __raw_readl(avic_base + ct->regs.mask);
98	__raw_writel(gc->wake_active, avic_base + ct->regs.mask);
99}
100
101static void avic_irq_resume(struct irq_data *d)
102{
103	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
104	struct irq_chip_type *ct = gc->chip_types;
105	int idx = d->hwirq >> 5;
106
107	__raw_writel(avic_saved_mask_reg[idx], avic_base + ct->regs.mask);
108}
109
110#else
111#define avic_irq_suspend NULL
112#define avic_irq_resume NULL
113#endif
114
115static __init void avic_init_gc(int idx, unsigned int irq_start)
116{
117	struct irq_chip_generic *gc;
118	struct irq_chip_type *ct;
119
120	gc = irq_alloc_generic_chip("mxc-avic", 1, irq_start, avic_base,
121				    handle_level_irq);
122	gc->private = &avic_extra_irq;
123	gc->wake_enabled = IRQ_MSK(32);
124
125	ct = gc->chip_types;
126	ct->chip.irq_mask = irq_gc_mask_clr_bit;
127	ct->chip.irq_unmask = irq_gc_mask_set_bit;
128	ct->chip.irq_ack = irq_gc_mask_clr_bit;
129	ct->chip.irq_set_wake = irq_gc_set_wake;
130	ct->chip.irq_suspend = avic_irq_suspend;
131	ct->chip.irq_resume = avic_irq_resume;
132	ct->regs.mask = !idx ? AVIC_INTENABLEL : AVIC_INTENABLEH;
133	ct->regs.ack = ct->regs.mask;
134
135	irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
136}
137
138static void __exception_irq_entry avic_handle_irq(struct pt_regs *regs)
139{
140	u32 nivector;
141
142	do {
143		nivector = __raw_readl(avic_base + AVIC_NIVECSR) >> 16;
144		if (nivector == 0xffff)
145			break;
146
147		handle_domain_irq(domain, nivector, regs);
148	} while (1);
149}
150
151/*
152 * This function initializes the AVIC hardware and disables all the
153 * interrupts. It registers the interrupt enable and disable functions
154 * to the kernel for each interrupt source.
155 */
156void __init mxc_init_irq(void __iomem *irqbase)
157{
158	struct device_node *np;
159	int irq_base;
160	int i;
161
162	avic_base = irqbase;
163
164	/* put the AVIC into the reset value with
165	 * all interrupts disabled
166	 */
167	__raw_writel(0, avic_base + AVIC_INTCNTL);
168	__raw_writel(0x1f, avic_base + AVIC_NIMASK);
169
170	/* disable all interrupts */
171	__raw_writel(0, avic_base + AVIC_INTENABLEH);
172	__raw_writel(0, avic_base + AVIC_INTENABLEL);
173
174	/* all IRQ no FIQ */
175	__raw_writel(0, avic_base + AVIC_INTTYPEH);
176	__raw_writel(0, avic_base + AVIC_INTTYPEL);
177
178	irq_base = irq_alloc_descs(-1, 0, AVIC_NUM_IRQS, numa_node_id());
179	WARN_ON(irq_base < 0);
180
181	np = of_find_compatible_node(NULL, NULL, "fsl,avic");
182	domain = irq_domain_add_legacy(np, AVIC_NUM_IRQS, irq_base, 0,
183				       &irq_domain_simple_ops, NULL);
184	WARN_ON(!domain);
185
186	for (i = 0; i < AVIC_NUM_IRQS / 32; i++, irq_base += 32)
187		avic_init_gc(i, irq_base);
188
189	/* Set default priority value (0) for all IRQ's */
190	for (i = 0; i < 8; i++)
191		__raw_writel(0, avic_base + AVIC_NIPRIORITY(i));
192
193	set_handle_irq(avic_handle_irq);
194
195#ifdef CONFIG_FIQ
196	/* Initialize FIQ */
197	init_FIQ(FIQ_START);
198#endif
199
200	printk(KERN_INFO "MXC IRQ initialized\n");
201}
202