1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
4 * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
5 */
6
7#include <linux/module.h>
8#include <linux/irq.h>
9#include <linux/irqdomain.h>
10#include <linux/irqchip.h>
11#include <linux/io.h>
12#include <linux/of.h>
13#include <linux/of_address.h>
14#include <asm/mach/irq.h>
15#include <asm/exception.h>
16
17#include "common.h"
18#include "hardware.h"
19#include "irq-common.h"
20
21#define AVIC_INTCNTL		0x00	/* int control reg */
22#define AVIC_NIMASK		0x04	/* int mask reg */
23#define AVIC_INTENNUM		0x08	/* int enable number reg */
24#define AVIC_INTDISNUM		0x0C	/* int disable number reg */
25#define AVIC_INTENABLEH		0x10	/* int enable reg high */
26#define AVIC_INTENABLEL		0x14	/* int enable reg low */
27#define AVIC_INTTYPEH		0x18	/* int type reg high */
28#define AVIC_INTTYPEL		0x1C	/* int type reg low */
29#define AVIC_NIPRIORITY(x)	(0x20 + 4 * (7 - (x))) /* int priority */
30#define AVIC_NIVECSR		0x40	/* norm int vector/status */
31#define AVIC_FIVECSR		0x44	/* fast int vector/status */
32#define AVIC_INTSRCH		0x48	/* int source reg high */
33#define AVIC_INTSRCL		0x4C	/* int source reg low */
34#define AVIC_INTFRCH		0x50	/* int force reg high */
35#define AVIC_INTFRCL		0x54	/* int force reg low */
36#define AVIC_NIPNDH		0x58	/* norm int pending high */
37#define AVIC_NIPNDL		0x5C	/* norm int pending low */
38#define AVIC_FIPNDH		0x60	/* fast int pending high */
39#define AVIC_FIPNDL		0x64	/* fast int pending low */
40
41#define AVIC_NUM_IRQS 64
42
43/* low power interrupt mask registers */
44#define MX25_CCM_LPIMR0	0x68
45#define MX25_CCM_LPIMR1	0x6C
46
47static void __iomem *avic_base;
48static void __iomem *mx25_ccm_base;
49static struct irq_domain *domain;
50
51#ifdef CONFIG_FIQ
52static int avic_set_irq_fiq(unsigned int hwirq, unsigned int type)
53{
54	unsigned int irqt;
55
56	if (hwirq >= AVIC_NUM_IRQS)
57		return -EINVAL;
58
59	if (hwirq < AVIC_NUM_IRQS / 2) {
60		irqt = imx_readl(avic_base + AVIC_INTTYPEL) & ~(1 << hwirq);
61		imx_writel(irqt | (!!type << hwirq), avic_base + AVIC_INTTYPEL);
62	} else {
63		hwirq -= AVIC_NUM_IRQS / 2;
64		irqt = imx_readl(avic_base + AVIC_INTTYPEH) & ~(1 << hwirq);
65		imx_writel(irqt | (!!type << hwirq), avic_base + AVIC_INTTYPEH);
66	}
67
68	return 0;
69}
70#endif /* CONFIG_FIQ */
71
72
73static struct mxc_extra_irq avic_extra_irq = {
74#ifdef CONFIG_FIQ
75	.set_irq_fiq = avic_set_irq_fiq,
76#endif
77};
78
79#ifdef CONFIG_PM
80static u32 avic_saved_mask_reg[2];
81
82static void avic_irq_suspend(struct irq_data *d)
83{
84	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
85	struct irq_chip_type *ct = gc->chip_types;
86	int idx = d->hwirq >> 5;
87
88	avic_saved_mask_reg[idx] = imx_readl(avic_base + ct->regs.mask);
89	imx_writel(gc->wake_active, avic_base + ct->regs.mask);
90
91	if (mx25_ccm_base) {
92		u8 offs = d->hwirq < AVIC_NUM_IRQS / 2 ?
93			MX25_CCM_LPIMR0 : MX25_CCM_LPIMR1;
94		/*
95		 * The interrupts which are still enabled will be used as wakeup
96		 * sources. Allow those interrupts in low-power mode.
97		 * The LPIMR registers use 0 to allow an interrupt, the AVIC
98		 * registers use 1.
99		 */
100		imx_writel(~gc->wake_active, mx25_ccm_base + offs);
101	}
102}
103
104static void avic_irq_resume(struct irq_data *d)
105{
106	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
107	struct irq_chip_type *ct = gc->chip_types;
108	int idx = d->hwirq >> 5;
109
110	imx_writel(avic_saved_mask_reg[idx], avic_base + ct->regs.mask);
111
112	if (mx25_ccm_base) {
113		u8 offs = d->hwirq < AVIC_NUM_IRQS / 2 ?
114			MX25_CCM_LPIMR0 : MX25_CCM_LPIMR1;
115
116		imx_writel(0xffffffff, mx25_ccm_base + offs);
117	}
118}
119
120#else
121#define avic_irq_suspend NULL
122#define avic_irq_resume NULL
123#endif
124
125static __init void avic_init_gc(int idx, unsigned int irq_start)
126{
127	struct irq_chip_generic *gc;
128	struct irq_chip_type *ct;
129
130	gc = irq_alloc_generic_chip("mxc-avic", 1, irq_start, avic_base,
131				    handle_level_irq);
132	gc->private = &avic_extra_irq;
133	gc->wake_enabled = IRQ_MSK(32);
134
135	ct = gc->chip_types;
136	ct->chip.irq_mask = irq_gc_mask_clr_bit;
137	ct->chip.irq_unmask = irq_gc_mask_set_bit;
138	ct->chip.irq_ack = irq_gc_mask_clr_bit;
139	ct->chip.irq_set_wake = irq_gc_set_wake;
140	ct->chip.irq_suspend = avic_irq_suspend;
141	ct->chip.irq_resume = avic_irq_resume;
142	ct->regs.mask = !idx ? AVIC_INTENABLEL : AVIC_INTENABLEH;
143	ct->regs.ack = ct->regs.mask;
144
145	irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
146}
147
148static void __exception_irq_entry avic_handle_irq(struct pt_regs *regs)
149{
150	u32 nivector;
151
152	do {
153		nivector = imx_readl(avic_base + AVIC_NIVECSR) >> 16;
154		if (nivector == 0xffff)
155			break;
156
157		generic_handle_domain_irq(domain, nivector);
158	} while (1);
159}
160
161/*
162 * This function initializes the AVIC hardware and disables all the
163 * interrupts. It registers the interrupt enable and disable functions
164 * to the kernel for each interrupt source.
165 */
166static void __init mxc_init_irq(void __iomem *irqbase)
167{
168	struct device_node *np;
169	int irq_base;
170	int i;
171
172	avic_base = irqbase;
173
174	np = of_find_compatible_node(NULL, NULL, "fsl,imx25-ccm");
175	mx25_ccm_base = of_iomap(np, 0);
176
177	if (mx25_ccm_base) {
178		/*
179		 * By default, we mask all interrupts. We set the actual mask
180		 * before we go into low-power mode.
181		 */
182		imx_writel(0xffffffff, mx25_ccm_base + MX25_CCM_LPIMR0);
183		imx_writel(0xffffffff, mx25_ccm_base + MX25_CCM_LPIMR1);
184	}
185
186	/* put the AVIC into the reset value with
187	 * all interrupts disabled
188	 */
189	imx_writel(0, avic_base + AVIC_INTCNTL);
190	imx_writel(0x1f, avic_base + AVIC_NIMASK);
191
192	/* disable all interrupts */
193	imx_writel(0, avic_base + AVIC_INTENABLEH);
194	imx_writel(0, avic_base + AVIC_INTENABLEL);
195
196	/* all IRQ no FIQ */
197	imx_writel(0, avic_base + AVIC_INTTYPEH);
198	imx_writel(0, avic_base + AVIC_INTTYPEL);
199
200	irq_base = irq_alloc_descs(-1, 0, AVIC_NUM_IRQS, numa_node_id());
201	WARN_ON(irq_base < 0);
202
203	np = of_find_compatible_node(NULL, NULL, "fsl,avic");
204	domain = irq_domain_add_legacy(np, AVIC_NUM_IRQS, irq_base, 0,
205				       &irq_domain_simple_ops, NULL);
206	WARN_ON(!domain);
207
208	for (i = 0; i < AVIC_NUM_IRQS / 32; i++, irq_base += 32)
209		avic_init_gc(i, irq_base);
210
211	/* Set default priority value (0) for all IRQ's */
212	for (i = 0; i < 8; i++)
213		imx_writel(0, avic_base + AVIC_NIPRIORITY(i));
214
215	set_handle_irq(avic_handle_irq);
216
217#ifdef CONFIG_FIQ
218	/* Initialize FIQ */
219	init_FIQ(FIQ_START);
220#endif
221
222	printk(KERN_INFO "MXC IRQ initialized\n");
223}
224
225static int __init imx_avic_init(struct device_node *node,
226			       struct device_node *parent)
227{
228	void __iomem *avic_base;
229
230	avic_base = of_iomap(node, 0);
231	BUG_ON(!avic_base);
232	mxc_init_irq(avic_base);
233	return 0;
234}
235
236IRQCHIP_DECLARE(imx_avic, "fsl,avic", imx_avic_init);
237