xref: /openbmc/linux/arch/arm/mach-tegra/irq.c (revision 1eb4c977)
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 <mach/iomap.h>
29 
30 #include "board.h"
31 
32 #define ICTLR_CPU_IEP_VFIQ	0x08
33 #define ICTLR_CPU_IEP_FIR	0x14
34 #define ICTLR_CPU_IEP_FIR_SET	0x18
35 #define ICTLR_CPU_IEP_FIR_CLR	0x1c
36 
37 #define ICTLR_CPU_IER		0x20
38 #define ICTLR_CPU_IER_SET	0x24
39 #define ICTLR_CPU_IER_CLR	0x28
40 #define ICTLR_CPU_IEP_CLASS	0x2C
41 
42 #define ICTLR_COP_IER		0x30
43 #define ICTLR_COP_IER_SET	0x34
44 #define ICTLR_COP_IER_CLR	0x38
45 #define ICTLR_COP_IEP_CLASS	0x3c
46 
47 #define FIRST_LEGACY_IRQ 32
48 
49 static int num_ictlrs;
50 
51 static void __iomem *ictlr_reg_base[] = {
52 	IO_ADDRESS(TEGRA_PRIMARY_ICTLR_BASE),
53 	IO_ADDRESS(TEGRA_SECONDARY_ICTLR_BASE),
54 	IO_ADDRESS(TEGRA_TERTIARY_ICTLR_BASE),
55 	IO_ADDRESS(TEGRA_QUATERNARY_ICTLR_BASE),
56 	IO_ADDRESS(TEGRA_QUINARY_ICTLR_BASE),
57 };
58 
59 static inline void tegra_irq_write_mask(unsigned int irq, unsigned long reg)
60 {
61 	void __iomem *base;
62 	u32 mask;
63 
64 	BUG_ON(irq < FIRST_LEGACY_IRQ ||
65 		irq >= FIRST_LEGACY_IRQ + num_ictlrs * 32);
66 
67 	base = ictlr_reg_base[(irq - FIRST_LEGACY_IRQ) / 32];
68 	mask = BIT((irq - FIRST_LEGACY_IRQ) % 32);
69 
70 	__raw_writel(mask, base + reg);
71 }
72 
73 static void tegra_mask(struct irq_data *d)
74 {
75 	if (d->irq < FIRST_LEGACY_IRQ)
76 		return;
77 
78 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IER_CLR);
79 }
80 
81 static void tegra_unmask(struct irq_data *d)
82 {
83 	if (d->irq < FIRST_LEGACY_IRQ)
84 		return;
85 
86 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IER_SET);
87 }
88 
89 static void tegra_ack(struct irq_data *d)
90 {
91 	if (d->irq < FIRST_LEGACY_IRQ)
92 		return;
93 
94 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IEP_FIR_CLR);
95 }
96 
97 static void tegra_eoi(struct irq_data *d)
98 {
99 	if (d->irq < FIRST_LEGACY_IRQ)
100 		return;
101 
102 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IEP_FIR_CLR);
103 }
104 
105 static int tegra_retrigger(struct irq_data *d)
106 {
107 	if (d->irq < FIRST_LEGACY_IRQ)
108 		return 0;
109 
110 	tegra_irq_write_mask(d->irq, ICTLR_CPU_IEP_FIR_SET);
111 
112 	return 1;
113 }
114 
115 void __init tegra_init_irq(void)
116 {
117 	int i;
118 	void __iomem *distbase;
119 
120 	distbase = IO_ADDRESS(TEGRA_ARM_INT_DIST_BASE);
121 	num_ictlrs = readl_relaxed(distbase + GIC_DIST_CTR) & 0x1f;
122 
123 	if (num_ictlrs > ARRAY_SIZE(ictlr_reg_base)) {
124 		WARN(1, "Too many (%d) interrupt controllers found. Maximum is %d.",
125 			num_ictlrs, ARRAY_SIZE(ictlr_reg_base));
126 		num_ictlrs = ARRAY_SIZE(ictlr_reg_base);
127 	}
128 
129 	for (i = 0; i < num_ictlrs; i++) {
130 		void __iomem *ictlr = ictlr_reg_base[i];
131 		writel(~0, ictlr + ICTLR_CPU_IER_CLR);
132 		writel(0, ictlr + ICTLR_CPU_IEP_CLASS);
133 	}
134 
135 	gic_arch_extn.irq_ack = tegra_ack;
136 	gic_arch_extn.irq_eoi = tegra_eoi;
137 	gic_arch_extn.irq_mask = tegra_mask;
138 	gic_arch_extn.irq_unmask = tegra_unmask;
139 	gic_arch_extn.irq_retrigger = tegra_retrigger;
140 
141 	/*
142 	 * Check if there is a devicetree present, since the GIC will be
143 	 * initialized elsewhere under DT.
144 	 */
145 	if (!of_have_populated_dt())
146 		gic_init(0, 29, distbase,
147 			IO_ADDRESS(TEGRA_ARM_PERIF_BASE + 0x100));
148 }
149