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(name: "mxc-avic", nr_ct: 1, irq_base: irq_start, reg_base: avic_base,
131 handler: 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), flags: 0, clr: IRQ_NOREQUEST, set: 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, compat: "fsl,imx25-ccm");
175 mx25_ccm_base = of_iomap(node: np, index: 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, compat: "fsl,avic");
204 domain = irq_domain_create_legacy(of_fwnode_handle(np), AVIC_NUM_IRQS, first_irq: irq_base, first_hwirq: 0,
205 ops: &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(idx: i, irq_start: 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, index: 0);
231 BUG_ON(!avic_base);
232 mxc_init_irq(irqbase: avic_base);
233 return 0;
234}
235
236IRQCHIP_DECLARE(imx_avic, "fsl,avic", imx_avic_init);
237

source code of linux/arch/arm/mach-imx/avic.c