xref: /openbmc/linux/arch/arm/mach-imx/tzic.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C)2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
4  */
5 
6 #include <linux/init.h>
7 #include <linux/device.h>
8 #include <linux/errno.h>
9 #include <linux/io.h>
10 #include <linux/irqchip.h>
11 #include <linux/irqdomain.h>
12 #include <linux/of.h>
13 #include <linux/of_address.h>
14 
15 #include <asm/mach/irq.h>
16 #include <asm/exception.h>
17 
18 #include "common.h"
19 #include "hardware.h"
20 #include "irq-common.h"
21 
22 /*
23  *****************************************
24  * TZIC Registers                        *
25  *****************************************
26  */
27 
28 #define TZIC_INTCNTL	0x0000	/* Control register */
29 #define TZIC_INTTYPE	0x0004	/* Controller Type register */
30 #define TZIC_IMPID	0x0008	/* Distributor Implementer Identification */
31 #define TZIC_PRIOMASK	0x000C	/* Priority Mask Reg */
32 #define TZIC_SYNCCTRL	0x0010	/* Synchronizer Control register */
33 #define TZIC_DSMINT	0x0014	/* DSM interrupt Holdoffregister */
34 #define TZIC_INTSEC0(i)	(0x0080 + ((i) << 2)) /* Interrupt Security Reg 0 */
35 #define TZIC_ENSET0(i)	(0x0100 + ((i) << 2)) /* Enable Set Reg 0 */
36 #define TZIC_ENCLEAR0(i) (0x0180 + ((i) << 2)) /* Enable Clear Reg 0 */
37 #define TZIC_SRCSET0	0x0200	/* Source Set Register 0 */
38 #define TZIC_SRCCLAR0	0x0280	/* Source Clear Register 0 */
39 #define TZIC_PRIORITY0	0x0400	/* Priority Register 0 */
40 #define TZIC_PND0	0x0D00	/* Pending Register 0 */
41 #define TZIC_HIPND(i)	(0x0D80+ ((i) << 2))	/* High Priority Pending Register */
42 #define TZIC_WAKEUP0(i)	(0x0E00 + ((i) << 2))	/* Wakeup Config Register */
43 #define TZIC_SWINT	0x0F00	/* Software Interrupt Rigger Register */
44 #define TZIC_ID0	0x0FD0	/* Indentification Register 0 */
45 
46 static void __iomem *tzic_base;
47 static struct irq_domain *domain;
48 
49 #define TZIC_NUM_IRQS 128
50 
51 #ifdef CONFIG_FIQ
52 static int tzic_set_irq_fiq(unsigned int hwirq, unsigned int type)
53 {
54 	unsigned int index, mask, value;
55 
56 	index = hwirq >> 5;
57 	if (unlikely(index >= 4))
58 		return -EINVAL;
59 	mask = 1U << (hwirq & 0x1F);
60 
61 	value = imx_readl(tzic_base + TZIC_INTSEC0(index)) | mask;
62 	if (type)
63 		value &= ~mask;
64 	imx_writel(value, tzic_base + TZIC_INTSEC0(index));
65 
66 	return 0;
67 }
68 #else
69 #define tzic_set_irq_fiq NULL
70 #endif
71 
72 #ifdef CONFIG_PM
73 static void tzic_irq_suspend(struct irq_data *d)
74 {
75 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
76 	int idx = d->hwirq >> 5;
77 
78 	imx_writel(gc->wake_active, tzic_base + TZIC_WAKEUP0(idx));
79 }
80 
81 static void tzic_irq_resume(struct irq_data *d)
82 {
83 	int idx = d->hwirq >> 5;
84 
85 	imx_writel(imx_readl(tzic_base + TZIC_ENSET0(idx)),
86 		   tzic_base + TZIC_WAKEUP0(idx));
87 }
88 
89 #else
90 #define tzic_irq_suspend NULL
91 #define tzic_irq_resume NULL
92 #endif
93 
94 static struct mxc_extra_irq tzic_extra_irq = {
95 #ifdef CONFIG_FIQ
96 	.set_irq_fiq = tzic_set_irq_fiq,
97 #endif
98 };
99 
100 static __init void tzic_init_gc(int idx, unsigned int irq_start)
101 {
102 	struct irq_chip_generic *gc;
103 	struct irq_chip_type *ct;
104 
105 	gc = irq_alloc_generic_chip("tzic", 1, irq_start, tzic_base,
106 				    handle_level_irq);
107 	gc->private = &tzic_extra_irq;
108 	gc->wake_enabled = IRQ_MSK(32);
109 
110 	ct = gc->chip_types;
111 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
112 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
113 	ct->chip.irq_set_wake = irq_gc_set_wake;
114 	ct->chip.irq_suspend = tzic_irq_suspend;
115 	ct->chip.irq_resume = tzic_irq_resume;
116 	ct->regs.disable = TZIC_ENCLEAR0(idx);
117 	ct->regs.enable = TZIC_ENSET0(idx);
118 
119 	irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
120 }
121 
122 static void __exception_irq_entry tzic_handle_irq(struct pt_regs *regs)
123 {
124 	u32 stat;
125 	int i, irqofs, handled;
126 
127 	do {
128 		handled = 0;
129 
130 		for (i = 0; i < 4; i++) {
131 			stat = imx_readl(tzic_base + TZIC_HIPND(i)) &
132 				imx_readl(tzic_base + TZIC_INTSEC0(i));
133 
134 			while (stat) {
135 				handled = 1;
136 				irqofs = fls(stat) - 1;
137 				handle_domain_irq(domain, irqofs + i * 32, regs);
138 				stat &= ~(1 << irqofs);
139 			}
140 		}
141 	} while (handled);
142 }
143 
144 /*
145  * This function initializes the TZIC hardware and disables all the
146  * interrupts. It registers the interrupt enable and disable functions
147  * to the kernel for each interrupt source.
148  */
149 static int __init tzic_init_dt(struct device_node *np, struct device_node *p)
150 {
151 	int irq_base;
152 	int i;
153 
154 	tzic_base = of_iomap(np, 0);
155 	WARN_ON(!tzic_base);
156 
157 	/* put the TZIC into the reset value with
158 	 * all interrupts disabled
159 	 */
160 	i = imx_readl(tzic_base + TZIC_INTCNTL);
161 
162 	imx_writel(0x80010001, tzic_base + TZIC_INTCNTL);
163 	imx_writel(0x1f, tzic_base + TZIC_PRIOMASK);
164 	imx_writel(0x02, tzic_base + TZIC_SYNCCTRL);
165 
166 	for (i = 0; i < 4; i++)
167 		imx_writel(0xFFFFFFFF, tzic_base + TZIC_INTSEC0(i));
168 
169 	/* disable all interrupts */
170 	for (i = 0; i < 4; i++)
171 		imx_writel(0xFFFFFFFF, tzic_base + TZIC_ENCLEAR0(i));
172 
173 	/* all IRQ no FIQ Warning :: No selection */
174 
175 	irq_base = irq_alloc_descs(-1, 0, TZIC_NUM_IRQS, numa_node_id());
176 	WARN_ON(irq_base < 0);
177 
178 	domain = irq_domain_add_legacy(np, TZIC_NUM_IRQS, irq_base, 0,
179 				       &irq_domain_simple_ops, NULL);
180 	WARN_ON(!domain);
181 
182 	for (i = 0; i < 4; i++, irq_base += 32)
183 		tzic_init_gc(i, irq_base);
184 
185 	set_handle_irq(tzic_handle_irq);
186 
187 #ifdef CONFIG_FIQ
188 	/* Initialize FIQ */
189 	init_FIQ(FIQ_START);
190 #endif
191 
192 	pr_info("TrustZone Interrupt Controller (TZIC) initialized\n");
193 
194 	return 0;
195 }
196 IRQCHIP_DECLARE(tzic, "fsl,tzic", tzic_init_dt);
197 
198 /**
199  * tzic_enable_wake() - enable wakeup interrupt
200  *
201  * @return			0 if successful; non-zero otherwise
202  *
203  * This function provides an interrupt synchronization point that is required
204  * by tzic enabled platforms before entering imx specific low power modes (ie,
205  * those low power modes beyond the WAIT_CLOCKED basic ARM WFI only mode).
206  */
207 int tzic_enable_wake(void)
208 {
209 	unsigned int i;
210 
211 	imx_writel(1, tzic_base + TZIC_DSMINT);
212 	if (unlikely(imx_readl(tzic_base + TZIC_DSMINT) == 0))
213 		return -EAGAIN;
214 
215 	for (i = 0; i < 4; i++)
216 		imx_writel(imx_readl(tzic_base + TZIC_ENSET0(i)),
217 			   tzic_base + TZIC_WAKEUP0(i));
218 
219 	return 0;
220 }
221