1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2002 ARM Limited, All Rights Reserved.
4 */
5
6 #include <linux/interrupt.h>
7 #include <linux/io.h>
8 #include <linux/irq.h>
9 #include <linux/irqchip/arm-gic.h>
10
11 #include "irq-gic-common.h"
12
13 static DEFINE_RAW_SPINLOCK(irq_controller_lock);
14
gic_enable_of_quirks(const struct device_node * np,const struct gic_quirk * quirks,void * data)15 void gic_enable_of_quirks(const struct device_node *np,
16 const struct gic_quirk *quirks, void *data)
17 {
18 for (; quirks->desc; quirks++) {
19 if (!of_device_is_compatible(np, quirks->compatible))
20 continue;
21 if (quirks->init(data))
22 pr_info("GIC: enabling workaround for %s\n",
23 quirks->desc);
24 }
25 }
26
gic_enable_quirks(u32 iidr,const struct gic_quirk * quirks,void * data)27 void gic_enable_quirks(u32 iidr, const struct gic_quirk *quirks,
28 void *data)
29 {
30 for (; quirks->desc; quirks++) {
31 if (quirks->compatible)
32 continue;
33 if (quirks->iidr != (quirks->mask & iidr))
34 continue;
35 if (quirks->init(data))
36 pr_info("GIC: enabling workaround for %s\n",
37 quirks->desc);
38 }
39 }
40
gic_configure_irq(unsigned int irq,unsigned int type,void __iomem * base,void (* sync_access)(void))41 int gic_configure_irq(unsigned int irq, unsigned int type,
42 void __iomem *base, void (*sync_access)(void))
43 {
44 u32 confmask = 0x2 << ((irq % 16) * 2);
45 u32 confoff = (irq / 16) * 4;
46 u32 val, oldval;
47 int ret = 0;
48 unsigned long flags;
49
50 /*
51 * Read current configuration register, and insert the config
52 * for "irq", depending on "type".
53 */
54 raw_spin_lock_irqsave(&irq_controller_lock, flags);
55 val = oldval = readl_relaxed(base + confoff);
56 if (type & IRQ_TYPE_LEVEL_MASK)
57 val &= ~confmask;
58 else if (type & IRQ_TYPE_EDGE_BOTH)
59 val |= confmask;
60
61 /* If the current configuration is the same, then we are done */
62 if (val == oldval) {
63 raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
64 return 0;
65 }
66
67 /*
68 * Write back the new configuration, and possibly re-enable
69 * the interrupt. If we fail to write a new configuration for
70 * an SPI then WARN and return an error. If we fail to write the
71 * configuration for a PPI this is most likely because the GIC
72 * does not allow us to set the configuration or we are in a
73 * non-secure mode, and hence it may not be catastrophic.
74 */
75 writel_relaxed(val, base + confoff);
76 if (readl_relaxed(base + confoff) != val)
77 ret = -EINVAL;
78
79 raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
80
81 if (sync_access)
82 sync_access();
83
84 return ret;
85 }
86
gic_dist_config(void __iomem * base,int gic_irqs,void (* sync_access)(void))87 void gic_dist_config(void __iomem *base, int gic_irqs,
88 void (*sync_access)(void))
89 {
90 unsigned int i;
91
92 /*
93 * Set all global interrupts to be level triggered, active low.
94 */
95 for (i = 32; i < gic_irqs; i += 16)
96 writel_relaxed(GICD_INT_ACTLOW_LVLTRIG,
97 base + GIC_DIST_CONFIG + i / 4);
98
99 /*
100 * Set priority on all global interrupts.
101 */
102 for (i = 32; i < gic_irqs; i += 4)
103 writel_relaxed(GICD_INT_DEF_PRI_X4, base + GIC_DIST_PRI + i);
104
105 /*
106 * Deactivate and disable all SPIs. Leave the PPI and SGIs
107 * alone as they are in the redistributor registers on GICv3.
108 */
109 for (i = 32; i < gic_irqs; i += 32) {
110 writel_relaxed(GICD_INT_EN_CLR_X32,
111 base + GIC_DIST_ACTIVE_CLEAR + i / 8);
112 writel_relaxed(GICD_INT_EN_CLR_X32,
113 base + GIC_DIST_ENABLE_CLEAR + i / 8);
114 }
115
116 if (sync_access)
117 sync_access();
118 }
119
gic_cpu_config(void __iomem * base,int nr,void (* sync_access)(void))120 void gic_cpu_config(void __iomem *base, int nr, void (*sync_access)(void))
121 {
122 int i;
123
124 /*
125 * Deal with the banked PPI and SGI interrupts - disable all
126 * private interrupts. Make sure everything is deactivated.
127 */
128 for (i = 0; i < nr; i += 32) {
129 writel_relaxed(GICD_INT_EN_CLR_X32,
130 base + GIC_DIST_ACTIVE_CLEAR + i / 8);
131 writel_relaxed(GICD_INT_EN_CLR_X32,
132 base + GIC_DIST_ENABLE_CLEAR + i / 8);
133 }
134
135 /*
136 * Set priority on PPI and SGI interrupts
137 */
138 for (i = 0; i < nr; i += 4)
139 writel_relaxed(GICD_INT_DEF_PRI_X4,
140 base + GIC_DIST_PRI + i * 4 / 4);
141
142 if (sync_access)
143 sync_access();
144 }
145