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 "init.h"
21
22 static const struct acpi_device_id amba_id_list[] = {
23 {"ARMH0061", 0}, /* PL061 GPIO Device */
24 {"ARMH0330", 0}, /* ARM DMA Controller DMA-330 */
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
amba_register_dummy_clk(void)36 static 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
amba_handler_attach(struct acpi_device * adev,const struct acpi_device_id * id)48 static int amba_handler_attach(struct acpi_device *adev,
49 const struct acpi_device_id *id)
50 {
51 struct acpi_device *parent = acpi_dev_parent(adev);
52 struct amba_device *dev;
53 struct resource_entry *rentry;
54 struct list_head resource_list;
55 bool address_found = false;
56 int irq_no = 0;
57 int ret;
58
59 /* If the ACPI node already has a physical device attached, skip it. */
60 if (adev->physical_node_count)
61 return 0;
62
63 dev = amba_device_alloc(dev_name(&adev->dev), 0, 0);
64 if (!dev) {
65 dev_err(&adev->dev, "%s(): amba_device_alloc() failed\n",
66 __func__);
67 return -ENOMEM;
68 }
69
70 INIT_LIST_HEAD(&resource_list);
71 ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
72 if (ret < 0)
73 goto err_free;
74
75 list_for_each_entry(rentry, &resource_list, node) {
76 switch (resource_type(rentry->res)) {
77 case IORESOURCE_MEM:
78 if (!address_found) {
79 dev->res = *rentry->res;
80 dev->res.name = dev_name(&dev->dev);
81 address_found = true;
82 }
83 break;
84 case IORESOURCE_IRQ:
85 if (irq_no < AMBA_NR_IRQS)
86 dev->irq[irq_no++] = rentry->res->start;
87 break;
88 default:
89 dev_warn(&adev->dev, "Invalid resource\n");
90 break;
91 }
92 }
93
94 acpi_dev_free_resource_list(&resource_list);
95
96 /*
97 * If the ACPI node has a parent and that parent has a physical device
98 * attached to it, that physical device should be the parent of
99 * the amba device we are about to create.
100 */
101 if (parent)
102 dev->dev.parent = acpi_get_first_physical_node(parent);
103
104 ACPI_COMPANION_SET(&dev->dev, adev);
105
106 ret = amba_device_add(dev, &iomem_resource);
107 if (ret) {
108 dev_err(&adev->dev, "%s(): amba_device_add() failed (%d)\n",
109 __func__, ret);
110 goto err_free;
111 }
112
113 return 1;
114
115 err_free:
116 amba_device_put(dev);
117 return ret;
118 }
119
120 static struct acpi_scan_handler amba_handler = {
121 .ids = amba_id_list,
122 .attach = amba_handler_attach,
123 };
124
acpi_amba_init(void)125 void __init acpi_amba_init(void)
126 {
127 amba_register_dummy_clk();
128 acpi_scan_add_handler(&amba_handler);
129 }
130