xref: /openbmc/linux/arch/arm/mach-imx/tzic.c (revision 588b48ca)
1 /*
2  * Copyright (C)2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
3  *
4  * The code contained herein is licensed under the GNU General Public
5  * License. You may obtain a copy of the GNU General Public License
6  * Version 2 or later at the following locations:
7  *
8  * http://www.opensource.org/licenses/gpl-license.html
9  * http://www.gnu.org/copyleft/gpl.html
10  */
11 
12 #include <linux/module.h>
13 #include <linux/moduleparam.h>
14 #include <linux/init.h>
15 #include <linux/device.h>
16 #include <linux/errno.h>
17 #include <linux/io.h>
18 #include <linux/irqdomain.h>
19 #include <linux/of.h>
20 #include <linux/of_address.h>
21 
22 #include <asm/mach/irq.h>
23 #include <asm/exception.h>
24 
25 #include "common.h"
26 #include "hardware.h"
27 #include "irq-common.h"
28 
29 /*
30  *****************************************
31  * TZIC Registers                        *
32  *****************************************
33  */
34 
35 #define TZIC_INTCNTL	0x0000	/* Control register */
36 #define TZIC_INTTYPE	0x0004	/* Controller Type register */
37 #define TZIC_IMPID	0x0008	/* Distributor Implementer Identification */
38 #define TZIC_PRIOMASK	0x000C	/* Priority Mask Reg */
39 #define TZIC_SYNCCTRL	0x0010	/* Synchronizer Control register */
40 #define TZIC_DSMINT	0x0014	/* DSM interrupt Holdoffregister */
41 #define TZIC_INTSEC0(i)	(0x0080 + ((i) << 2)) /* Interrupt Security Reg 0 */
42 #define TZIC_ENSET0(i)	(0x0100 + ((i) << 2)) /* Enable Set Reg 0 */
43 #define TZIC_ENCLEAR0(i) (0x0180 + ((i) << 2)) /* Enable Clear Reg 0 */
44 #define TZIC_SRCSET0	0x0200	/* Source Set Register 0 */
45 #define TZIC_SRCCLAR0	0x0280	/* Source Clear Register 0 */
46 #define TZIC_PRIORITY0	0x0400	/* Priority Register 0 */
47 #define TZIC_PND0	0x0D00	/* Pending Register 0 */
48 #define TZIC_HIPND(i)	(0x0D80+ ((i) << 2))	/* High Priority Pending Register */
49 #define TZIC_WAKEUP0(i)	(0x0E00 + ((i) << 2))	/* Wakeup Config Register */
50 #define TZIC_SWINT	0x0F00	/* Software Interrupt Rigger Register */
51 #define TZIC_ID0	0x0FD0	/* Indentification Register 0 */
52 
53 static void __iomem *tzic_base;
54 static struct irq_domain *domain;
55 
56 #define TZIC_NUM_IRQS 128
57 
58 #ifdef CONFIG_FIQ
59 static int tzic_set_irq_fiq(unsigned int irq, unsigned int type)
60 {
61 	unsigned int index, mask, value;
62 
63 	index = irq >> 5;
64 	if (unlikely(index >= 4))
65 		return -EINVAL;
66 	mask = 1U << (irq & 0x1F);
67 
68 	value = __raw_readl(tzic_base + TZIC_INTSEC0(index)) | mask;
69 	if (type)
70 		value &= ~mask;
71 	__raw_writel(value, tzic_base + TZIC_INTSEC0(index));
72 
73 	return 0;
74 }
75 #else
76 #define tzic_set_irq_fiq NULL
77 #endif
78 
79 #ifdef CONFIG_PM
80 static void tzic_irq_suspend(struct irq_data *d)
81 {
82 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
83 	int idx = d->hwirq >> 5;
84 
85 	__raw_writel(gc->wake_active, tzic_base + TZIC_WAKEUP0(idx));
86 }
87 
88 static void tzic_irq_resume(struct irq_data *d)
89 {
90 	int idx = d->hwirq >> 5;
91 
92 	__raw_writel(__raw_readl(tzic_base + TZIC_ENSET0(idx)),
93 		     tzic_base + TZIC_WAKEUP0(idx));
94 }
95 
96 #else
97 #define tzic_irq_suspend NULL
98 #define tzic_irq_resume NULL
99 #endif
100 
101 static struct mxc_extra_irq tzic_extra_irq = {
102 #ifdef CONFIG_FIQ
103 	.set_irq_fiq = tzic_set_irq_fiq,
104 #endif
105 };
106 
107 static __init void tzic_init_gc(int idx, unsigned int irq_start)
108 {
109 	struct irq_chip_generic *gc;
110 	struct irq_chip_type *ct;
111 
112 	gc = irq_alloc_generic_chip("tzic", 1, irq_start, tzic_base,
113 				    handle_level_irq);
114 	gc->private = &tzic_extra_irq;
115 	gc->wake_enabled = IRQ_MSK(32);
116 
117 	ct = gc->chip_types;
118 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
119 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
120 	ct->chip.irq_set_wake = irq_gc_set_wake;
121 	ct->chip.irq_suspend = tzic_irq_suspend;
122 	ct->chip.irq_resume = tzic_irq_resume;
123 	ct->regs.disable = TZIC_ENCLEAR0(idx);
124 	ct->regs.enable = TZIC_ENSET0(idx);
125 
126 	irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
127 }
128 
129 static void __exception_irq_entry tzic_handle_irq(struct pt_regs *regs)
130 {
131 	u32 stat;
132 	int i, irqofs, handled;
133 
134 	do {
135 		handled = 0;
136 
137 		for (i = 0; i < 4; i++) {
138 			stat = __raw_readl(tzic_base + TZIC_HIPND(i)) &
139 				__raw_readl(tzic_base + TZIC_INTSEC0(i));
140 
141 			while (stat) {
142 				handled = 1;
143 				irqofs = fls(stat) - 1;
144 				handle_IRQ(irq_find_mapping(domain,
145 						irqofs + i * 32), regs);
146 				stat &= ~(1 << irqofs);
147 			}
148 		}
149 	} while (handled);
150 }
151 
152 /*
153  * This function initializes the TZIC hardware and disables all the
154  * interrupts. It registers the interrupt enable and disable functions
155  * to the kernel for each interrupt source.
156  */
157 void __init tzic_init_irq(void)
158 {
159 	struct device_node *np;
160 	int irq_base;
161 	int i;
162 
163 	np = of_find_compatible_node(NULL, NULL, "fsl,tzic");
164 	tzic_base = of_iomap(np, 0);
165 	WARN_ON(!tzic_base);
166 
167 	/* put the TZIC into the reset value with
168 	 * all interrupts disabled
169 	 */
170 	i = __raw_readl(tzic_base + TZIC_INTCNTL);
171 
172 	__raw_writel(0x80010001, tzic_base + TZIC_INTCNTL);
173 	__raw_writel(0x1f, tzic_base + TZIC_PRIOMASK);
174 	__raw_writel(0x02, tzic_base + TZIC_SYNCCTRL);
175 
176 	for (i = 0; i < 4; i++)
177 		__raw_writel(0xFFFFFFFF, tzic_base + TZIC_INTSEC0(i));
178 
179 	/* disable all interrupts */
180 	for (i = 0; i < 4; i++)
181 		__raw_writel(0xFFFFFFFF, tzic_base + TZIC_ENCLEAR0(i));
182 
183 	/* all IRQ no FIQ Warning :: No selection */
184 
185 	irq_base = irq_alloc_descs(-1, 0, TZIC_NUM_IRQS, numa_node_id());
186 	WARN_ON(irq_base < 0);
187 
188 	domain = irq_domain_add_legacy(np, TZIC_NUM_IRQS, irq_base, 0,
189 				       &irq_domain_simple_ops, NULL);
190 	WARN_ON(!domain);
191 
192 	for (i = 0; i < 4; i++, irq_base += 32)
193 		tzic_init_gc(i, irq_base);
194 
195 	set_handle_irq(tzic_handle_irq);
196 
197 #ifdef CONFIG_FIQ
198 	/* Initialize FIQ */
199 	init_FIQ(FIQ_START);
200 #endif
201 
202 	pr_info("TrustZone Interrupt Controller (TZIC) initialized\n");
203 }
204 
205 /**
206  * tzic_enable_wake() - enable wakeup interrupt
207  *
208  * @return			0 if successful; non-zero otherwise
209  *
210  * This function provides an interrupt synchronization point that is required
211  * by tzic enabled platforms before entering imx specific low power modes (ie,
212  * those low power modes beyond the WAIT_CLOCKED basic ARM WFI only mode).
213  */
214 int tzic_enable_wake(void)
215 {
216 	unsigned int i;
217 
218 	__raw_writel(1, tzic_base + TZIC_DSMINT);
219 	if (unlikely(__raw_readl(tzic_base + TZIC_DSMINT) == 0))
220 		return -EAGAIN;
221 
222 	for (i = 0; i < 4; i++)
223 		__raw_writel(__raw_readl(tzic_base + TZIC_ENSET0(i)),
224 			     tzic_base + TZIC_WAKEUP0(i));
225 
226 	return 0;
227 }
228