xref: /openbmc/linux/arch/arm/mach-imx/tzic.c (revision e3b9f1e8)
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/init.h>
13 #include <linux/device.h>
14 #include <linux/errno.h>
15 #include <linux/io.h>
16 #include <linux/irqchip.h>
17 #include <linux/irqdomain.h>
18 #include <linux/of.h>
19 #include <linux/of_address.h>
20 
21 #include <asm/mach/irq.h>
22 #include <asm/exception.h>
23 
24 #include "common.h"
25 #include "hardware.h"
26 #include "irq-common.h"
27 
28 /*
29  *****************************************
30  * TZIC Registers                        *
31  *****************************************
32  */
33 
34 #define TZIC_INTCNTL	0x0000	/* Control register */
35 #define TZIC_INTTYPE	0x0004	/* Controller Type register */
36 #define TZIC_IMPID	0x0008	/* Distributor Implementer Identification */
37 #define TZIC_PRIOMASK	0x000C	/* Priority Mask Reg */
38 #define TZIC_SYNCCTRL	0x0010	/* Synchronizer Control register */
39 #define TZIC_DSMINT	0x0014	/* DSM interrupt Holdoffregister */
40 #define TZIC_INTSEC0(i)	(0x0080 + ((i) << 2)) /* Interrupt Security Reg 0 */
41 #define TZIC_ENSET0(i)	(0x0100 + ((i) << 2)) /* Enable Set Reg 0 */
42 #define TZIC_ENCLEAR0(i) (0x0180 + ((i) << 2)) /* Enable Clear Reg 0 */
43 #define TZIC_SRCSET0	0x0200	/* Source Set Register 0 */
44 #define TZIC_SRCCLAR0	0x0280	/* Source Clear Register 0 */
45 #define TZIC_PRIORITY0	0x0400	/* Priority Register 0 */
46 #define TZIC_PND0	0x0D00	/* Pending Register 0 */
47 #define TZIC_HIPND(i)	(0x0D80+ ((i) << 2))	/* High Priority Pending Register */
48 #define TZIC_WAKEUP0(i)	(0x0E00 + ((i) << 2))	/* Wakeup Config Register */
49 #define TZIC_SWINT	0x0F00	/* Software Interrupt Rigger Register */
50 #define TZIC_ID0	0x0FD0	/* Indentification Register 0 */
51 
52 static void __iomem *tzic_base;
53 static struct irq_domain *domain;
54 
55 #define TZIC_NUM_IRQS 128
56 
57 #ifdef CONFIG_FIQ
58 static int tzic_set_irq_fiq(unsigned int hwirq, unsigned int type)
59 {
60 	unsigned int index, mask, value;
61 
62 	index = hwirq >> 5;
63 	if (unlikely(index >= 4))
64 		return -EINVAL;
65 	mask = 1U << (hwirq & 0x1F);
66 
67 	value = imx_readl(tzic_base + TZIC_INTSEC0(index)) | mask;
68 	if (type)
69 		value &= ~mask;
70 	imx_writel(value, tzic_base + TZIC_INTSEC0(index));
71 
72 	return 0;
73 }
74 #else
75 #define tzic_set_irq_fiq NULL
76 #endif
77 
78 #ifdef CONFIG_PM
79 static void tzic_irq_suspend(struct irq_data *d)
80 {
81 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
82 	int idx = d->hwirq >> 5;
83 
84 	imx_writel(gc->wake_active, tzic_base + TZIC_WAKEUP0(idx));
85 }
86 
87 static void tzic_irq_resume(struct irq_data *d)
88 {
89 	int idx = d->hwirq >> 5;
90 
91 	imx_writel(imx_readl(tzic_base + TZIC_ENSET0(idx)),
92 		   tzic_base + TZIC_WAKEUP0(idx));
93 }
94 
95 #else
96 #define tzic_irq_suspend NULL
97 #define tzic_irq_resume NULL
98 #endif
99 
100 static struct mxc_extra_irq tzic_extra_irq = {
101 #ifdef CONFIG_FIQ
102 	.set_irq_fiq = tzic_set_irq_fiq,
103 #endif
104 };
105 
106 static __init void tzic_init_gc(int idx, unsigned int irq_start)
107 {
108 	struct irq_chip_generic *gc;
109 	struct irq_chip_type *ct;
110 
111 	gc = irq_alloc_generic_chip("tzic", 1, irq_start, tzic_base,
112 				    handle_level_irq);
113 	gc->private = &tzic_extra_irq;
114 	gc->wake_enabled = IRQ_MSK(32);
115 
116 	ct = gc->chip_types;
117 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
118 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
119 	ct->chip.irq_set_wake = irq_gc_set_wake;
120 	ct->chip.irq_suspend = tzic_irq_suspend;
121 	ct->chip.irq_resume = tzic_irq_resume;
122 	ct->regs.disable = TZIC_ENCLEAR0(idx);
123 	ct->regs.enable = TZIC_ENSET0(idx);
124 
125 	irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
126 }
127 
128 static void __exception_irq_entry tzic_handle_irq(struct pt_regs *regs)
129 {
130 	u32 stat;
131 	int i, irqofs, handled;
132 
133 	do {
134 		handled = 0;
135 
136 		for (i = 0; i < 4; i++) {
137 			stat = imx_readl(tzic_base + TZIC_HIPND(i)) &
138 				imx_readl(tzic_base + TZIC_INTSEC0(i));
139 
140 			while (stat) {
141 				handled = 1;
142 				irqofs = fls(stat) - 1;
143 				handle_domain_irq(domain, irqofs + i * 32, regs);
144 				stat &= ~(1 << irqofs);
145 			}
146 		}
147 	} while (handled);
148 }
149 
150 /*
151  * This function initializes the TZIC hardware and disables all the
152  * interrupts. It registers the interrupt enable and disable functions
153  * to the kernel for each interrupt source.
154  */
155 static int __init tzic_init_dt(struct device_node *np, struct device_node *p)
156 {
157 	int irq_base;
158 	int i;
159 
160 	tzic_base = of_iomap(np, 0);
161 	WARN_ON(!tzic_base);
162 
163 	/* put the TZIC into the reset value with
164 	 * all interrupts disabled
165 	 */
166 	i = imx_readl(tzic_base + TZIC_INTCNTL);
167 
168 	imx_writel(0x80010001, tzic_base + TZIC_INTCNTL);
169 	imx_writel(0x1f, tzic_base + TZIC_PRIOMASK);
170 	imx_writel(0x02, tzic_base + TZIC_SYNCCTRL);
171 
172 	for (i = 0; i < 4; i++)
173 		imx_writel(0xFFFFFFFF, tzic_base + TZIC_INTSEC0(i));
174 
175 	/* disable all interrupts */
176 	for (i = 0; i < 4; i++)
177 		imx_writel(0xFFFFFFFF, tzic_base + TZIC_ENCLEAR0(i));
178 
179 	/* all IRQ no FIQ Warning :: No selection */
180 
181 	irq_base = irq_alloc_descs(-1, 0, TZIC_NUM_IRQS, numa_node_id());
182 	WARN_ON(irq_base < 0);
183 
184 	domain = irq_domain_add_legacy(np, TZIC_NUM_IRQS, irq_base, 0,
185 				       &irq_domain_simple_ops, NULL);
186 	WARN_ON(!domain);
187 
188 	for (i = 0; i < 4; i++, irq_base += 32)
189 		tzic_init_gc(i, irq_base);
190 
191 	set_handle_irq(tzic_handle_irq);
192 
193 #ifdef CONFIG_FIQ
194 	/* Initialize FIQ */
195 	init_FIQ(FIQ_START);
196 #endif
197 
198 	pr_info("TrustZone Interrupt Controller (TZIC) initialized\n");
199 
200 	return 0;
201 }
202 IRQCHIP_DECLARE(tzic, "fsl,tzic", tzic_init_dt);
203 
204 /**
205  * tzic_enable_wake() - enable wakeup interrupt
206  *
207  * @return			0 if successful; non-zero otherwise
208  *
209  * This function provides an interrupt synchronization point that is required
210  * by tzic enabled platforms before entering imx specific low power modes (ie,
211  * those low power modes beyond the WAIT_CLOCKED basic ARM WFI only mode).
212  */
213 int tzic_enable_wake(void)
214 {
215 	unsigned int i;
216 
217 	imx_writel(1, tzic_base + TZIC_DSMINT);
218 	if (unlikely(imx_readl(tzic_base + TZIC_DSMINT) == 0))
219 		return -EAGAIN;
220 
221 	for (i = 0; i < 4; i++)
222 		imx_writel(imx_readl(tzic_base + TZIC_ENSET0(i)),
223 			   tzic_base + TZIC_WAKEUP0(i));
224 
225 	return 0;
226 }
227