1// SPDX-License-Identifier: GPL-2.0-only
2
3/*
4 * ACPI support for platform bus type.
5 *
6 * Copyright (C) 2015, Linaro Ltd
7 * Author: Graeme Gregory <graeme.gregory@linaro.org>
8 */
9
10#include <linux/acpi.h>
11#include <linux/amba/bus.h>
12#include <linux/clkdev.h>
13#include <linux/clk-provider.h>
14#include <linux/device.h>
15#include <linux/err.h>
16#include <linux/ioport.h>
17#include <linux/kernel.h>
18#include <linux/module.h>
19
20#include "internal.h"
21
22static const struct acpi_device_id amba_id_list[] = {
23	{"ARMH0061", 0}, /* PL061 GPIO Device */
24	{"ARMHC500", 0}, /* ARM CoreSight ETM4x */
25	{"ARMHC501", 0}, /* ARM CoreSight ETR */
26	{"ARMHC502", 0}, /* ARM CoreSight STM */
27	{"ARMHC503", 0}, /* ARM CoreSight Debug */
28	{"ARMHC979", 0}, /* ARM CoreSight TPIU */
29	{"ARMHC97C", 0}, /* ARM CoreSight SoC-400 TMC, SoC-600 ETF/ETB */
30	{"ARMHC98D", 0}, /* ARM CoreSight Dynamic Replicator */
31	{"ARMHC9CA", 0}, /* ARM CoreSight CATU */
32	{"ARMHC9FF", 0}, /* ARM CoreSight Dynamic Funnel */
33	{"", 0},
34};
35
36static void amba_register_dummy_clk(void)
37{
38	static struct clk *amba_dummy_clk;
39
40	/* If clock already registered */
41	if (amba_dummy_clk)
42		return;
43
44	amba_dummy_clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, 0, 0);
45	clk_register_clkdev(amba_dummy_clk, "apb_pclk", NULL);
46}
47
48static int amba_handler_attach(struct acpi_device *adev,
49				const struct acpi_device_id *id)
50{
51	struct amba_device *dev;
52	struct resource_entry *rentry;
53	struct list_head resource_list;
54	bool address_found = false;
55	int irq_no = 0;
56	int ret;
57
58	/* If the ACPI node already has a physical device attached, skip it. */
59	if (adev->physical_node_count)
60		return 0;
61
62	dev = amba_device_alloc(dev_name(&adev->dev), 0, 0);
63	if (!dev) {
64		dev_err(&adev->dev, "%s(): amba_device_alloc() failed\n",
65			__func__);
66		return -ENOMEM;
67	}
68
69	INIT_LIST_HEAD(&resource_list);
70	ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
71	if (ret < 0)
72		goto err_free;
73
74	list_for_each_entry(rentry, &resource_list, node) {
75		switch (resource_type(rentry->res)) {
76		case IORESOURCE_MEM:
77			if (!address_found) {
78				dev->res = *rentry->res;
79				dev->res.name = dev_name(&dev->dev);
80				address_found = true;
81			}
82			break;
83		case IORESOURCE_IRQ:
84			if (irq_no < AMBA_NR_IRQS)
85				dev->irq[irq_no++] = rentry->res->start;
86			break;
87		default:
88			dev_warn(&adev->dev, "Invalid resource\n");
89			break;
90		}
91	}
92
93	acpi_dev_free_resource_list(&resource_list);
94
95	/*
96	 * If the ACPI node has a parent and that parent has a physical device
97	 * attached to it, that physical device should be the parent of
98	 * the amba device we are about to create.
99	 */
100	if (adev->parent)
101		dev->dev.parent = acpi_get_first_physical_node(adev->parent);
102
103	ACPI_COMPANION_SET(&dev->dev, adev);
104
105	ret = amba_device_add(dev, &iomem_resource);
106	if (ret) {
107		dev_err(&adev->dev, "%s(): amba_device_add() failed (%d)\n",
108		       __func__, ret);
109		goto err_free;
110	}
111
112	return 1;
113
114err_free:
115	amba_device_put(dev);
116	return ret;
117}
118
119static struct acpi_scan_handler amba_handler = {
120	.ids = amba_id_list,
121	.attach = amba_handler_attach,
122};
123
124void __init acpi_amba_init(void)
125{
126	amba_register_dummy_clk();
127	acpi_scan_add_handler(&amba_handler);
128}
129