1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2019 Google, LLC
4  * Written by Simon Glass <sjg@chromium.org>
5  */
6 
7 #define LOG_CATEGORY	UCLASS_IRQ
8 
9 #include <common.h>
10 #include <dm.h>
11 #include <irq.h>
12 #include <log.h>
13 #include <acpi/acpi_device.h>
14 #include <asm/io.h>
15 #include <dt-bindings/interrupt-controller/irq.h>
16 #include <dt-bindings/interrupt-controller/x86-irq.h>
17 
18 /**
19  * struct acpi_gpe_priv - private driver information
20  *
21  * @acpi_base: Base I/O address of ACPI registers
22  */
23 struct acpi_gpe_priv {
24 	ulong acpi_base;
25 };
26 
27 #define GPE0_STS(x)		(0x20 + ((x) * 4))
28 
acpi_gpe_read_and_clear(struct irq * irq)29 static int acpi_gpe_read_and_clear(struct irq *irq)
30 {
31 	struct acpi_gpe_priv *priv = dev_get_priv(irq->dev);
32 	u32 mask, sts;
33 	ulong start;
34 	int ret = 0;
35 	int bank;
36 
37 	bank = irq->id / 32;
38 	mask = 1 << (irq->id % 32);
39 
40 	/* Wait up to 1ms for GPE status to clear */
41 	start = get_timer(0);
42 	do {
43 		if (get_timer(start) > 1)
44 			return ret;
45 
46 		sts = inl(priv->acpi_base + GPE0_STS(bank));
47 		if (sts & mask) {
48 			outl(mask, priv->acpi_base + GPE0_STS(bank));
49 			ret = 1;
50 		}
51 	} while (sts & mask);
52 
53 	return ret;
54 }
55 
acpi_gpe_of_to_plat(struct udevice * dev)56 static int acpi_gpe_of_to_plat(struct udevice *dev)
57 {
58 	struct acpi_gpe_priv *priv = dev_get_priv(dev);
59 
60 	priv->acpi_base = dev_read_addr(dev);
61 	if (!priv->acpi_base || priv->acpi_base == FDT_ADDR_T_NONE)
62 		return log_msg_ret("acpi_base", -EINVAL);
63 
64 	return 0;
65 }
66 
acpi_gpe_of_xlate(struct irq * irq,struct ofnode_phandle_args * args)67 static int acpi_gpe_of_xlate(struct irq *irq, struct ofnode_phandle_args *args)
68 {
69 	irq->id = args->args[0];
70 	irq->flags = args->args[1];
71 
72 	return 0;
73 }
74 
75 #if CONFIG_IS_ENABLED(ACPIGEN)
acpi_gpe_get_acpi(const struct irq * irq,struct acpi_irq * acpi_irq)76 static int acpi_gpe_get_acpi(const struct irq *irq, struct acpi_irq *acpi_irq)
77 {
78 	memset(acpi_irq, '\0', sizeof(*acpi_irq));
79 	acpi_irq->pin = irq->id;
80 	acpi_irq->mode = irq->flags & IRQ_TYPE_EDGE_BOTH ?
81 		ACPI_IRQ_EDGE_TRIGGERED : ACPI_IRQ_LEVEL_TRIGGERED;
82 	acpi_irq->polarity = irq->flags &
83 		 (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_LEVEL_LOW) ?
84 		 ACPI_IRQ_ACTIVE_LOW : ACPI_IRQ_ACTIVE_HIGH;
85 	acpi_irq->shared = irq->flags & X86_IRQ_TYPE_SHARED ?
86 		ACPI_IRQ_SHARED : ACPI_IRQ_EXCLUSIVE;
87 	acpi_irq->wake = irq->flags & X86_IRQ_TYPE_WAKE ? ACPI_IRQ_WAKE :
88 		ACPI_IRQ_NO_WAKE;
89 
90 	return 0;
91 }
92 #endif
93 
94 static const struct irq_ops acpi_gpe_ops = {
95 	.read_and_clear		= acpi_gpe_read_and_clear,
96 	.of_xlate		= acpi_gpe_of_xlate,
97 #if CONFIG_IS_ENABLED(ACPIGEN)
98 	.get_acpi		= acpi_gpe_get_acpi,
99 #endif
100 };
101 
102 static const struct udevice_id acpi_gpe_ids[] = {
103 	{ .compatible = "intel,acpi-gpe", .data = X86_IRQT_ACPI_GPE },
104 	{ }
105 };
106 
107 U_BOOT_DRIVER(intel_acpi_gpe) = {
108 	.name		= "intel_acpi_gpe",
109 	.id		= UCLASS_IRQ,
110 	.of_match	= acpi_gpe_ids,
111 	.ops		= &acpi_gpe_ops,
112 	.of_to_plat	= acpi_gpe_of_to_plat,
113 	.priv_auto	= sizeof(struct acpi_gpe_priv),
114 };
115