xref: /openbmc/linux/arch/arm/mach-tegra/irq.c (revision 54cbac81)
1 /*
2  * Copyright (C) 2011 Google, Inc.
3  *
4  * Author:
5  *	Colin Cross <ccross@android.com>
6  *
7  * Copyright (C) 2010, NVIDIA Corporation
8  *
9  * This software is licensed under the terms of the GNU General Public
10  * License version 2, as published by the Free Software Foundation, and
11  * may be copied, distributed, and modified under those terms.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  */
19 
20 #include <linux/kernel.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
23 #include <linux/io.h>
24 #include <linux/of.h>
25 
26 #include <asm/hardware/gic.h>
27 
28 #include "board.h"
29 #include "iomap.h"
30 
31 #define ICTLR_CPU_IEP_VFIQ	0x08
32 #define ICTLR_CPU_IEP_FIR	0x14
33 #define ICTLR_CPU_IEP_FIR_SET	0x18
34 #define ICTLR_CPU_IEP_FIR_CLR	0x1c
35 
36 #define ICTLR_CPU_IER		0x20
37 #define ICTLR_CPU_IER_SET	0x24
38 #define ICTLR_CPU_IER_CLR	0x28
39 #define ICTLR_CPU_IEP_CLASS	0x2C
40 
41 #define ICTLR_COP_IER		0x30
42 #define ICTLR_COP_IER_SET	0x34
43 #define ICTLR_COP_IER_CLR	0x38
44 #define ICTLR_COP_IEP_CLASS	0x3c
45 
46 #define FIRST_LEGACY_IRQ 32
47 
48 static int num_ictlrs;
49 
50 static void __iomem *ictlr_reg_base[] = {
51 	IO_ADDRESS(TEGRA_PRIMARY_ICTLR_BASE),
52 	IO_ADDRESS(TEGRA_SECONDARY_ICTLR_BASE),
53 	IO_ADDRESS(TEGRA_TERTIARY_ICTLR_BASE),
54 	IO_ADDRESS(TEGRA_QUATERNARY_ICTLR_BASE),
55 	IO_ADDRESS(TEGRA_QUINARY_ICTLR_BASE),
56 };
57 
58 static inline void tegra_irq_write_mask(unsigned int irq, unsigned long reg)
59 {
60 	void __iomem *base;
61 	u32 mask;
62 
63 	BUG_ON(irq < FIRST_LEGACY_IRQ ||
64 		irq >= FIRST_LEGACY_IRQ + num_ictlrs * 32);
65 
66 	base = ictlr_reg_base[(irq - FIRST_LEGACY_IRQ) / 32];
67 	mask = BIT((irq - FIRST_LEGACY_IRQ) % 32);
68 
69 	__raw_writel(mask, base + reg);
70 }
71 
72 static void tegra_mask(struct irq_data *d)
73 {
74 	if (d->irq < FIRST_LEGACY_IRQ)
75 		return;
76 
77 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IER_CLR);
78 }
79 
80 static void tegra_unmask(struct irq_data *d)
81 {
82 	if (d->irq < FIRST_LEGACY_IRQ)
83 		return;
84 
85 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IER_SET);
86 }
87 
88 static void tegra_ack(struct irq_data *d)
89 {
90 	if (d->irq < FIRST_LEGACY_IRQ)
91 		return;
92 
93 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IEP_FIR_CLR);
94 }
95 
96 static void tegra_eoi(struct irq_data *d)
97 {
98 	if (d->irq < FIRST_LEGACY_IRQ)
99 		return;
100 
101 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IEP_FIR_CLR);
102 }
103 
104 static int tegra_retrigger(struct irq_data *d)
105 {
106 	if (d->irq < FIRST_LEGACY_IRQ)
107 		return 0;
108 
109 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IEP_FIR_SET);
110 
111 	return 1;
112 }
113 
114 void __init tegra_init_irq(void)
115 {
116 	int i;
117 	void __iomem *distbase;
118 
119 	distbase = IO_ADDRESS(TEGRA_ARM_INT_DIST_BASE);
120 	num_ictlrs = readl_relaxed(distbase + GIC_DIST_CTR) & 0x1f;
121 
122 	if (num_ictlrs > ARRAY_SIZE(ictlr_reg_base)) {
123 		WARN(1, "Too many (%d) interrupt controllers found. Maximum is %d.",
124 			num_ictlrs, ARRAY_SIZE(ictlr_reg_base));
125 		num_ictlrs = ARRAY_SIZE(ictlr_reg_base);
126 	}
127 
128 	for (i = 0; i < num_ictlrs; i++) {
129 		void __iomem *ictlr = ictlr_reg_base[i];
130 		writel(~0, ictlr + ICTLR_CPU_IER_CLR);
131 		writel(0, ictlr + ICTLR_CPU_IEP_CLASS);
132 	}
133 
134 	gic_arch_extn.irq_ack = tegra_ack;
135 	gic_arch_extn.irq_eoi = tegra_eoi;
136 	gic_arch_extn.irq_mask = tegra_mask;
137 	gic_arch_extn.irq_unmask = tegra_unmask;
138 	gic_arch_extn.irq_retrigger = tegra_retrigger;
139 
140 	/*
141 	 * Check if there is a devicetree present, since the GIC will be
142 	 * initialized elsewhere under DT.
143 	 */
144 	if (!of_have_populated_dt())
145 		gic_init(0, 29, distbase,
146 			IO_ADDRESS(TEGRA_ARM_PERIF_BASE + 0x100));
147 }
148