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
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 {"ARMHC500", 0}, /* ARM CoreSight ETM4x */
26 {"ARMHC501", 0}, /* ARM CoreSight ETR */
27 {"ARMHC502", 0}, /* ARM CoreSight STM */
28 {"ARMHC503", 0}, /* ARM CoreSight Debug */
29 {"ARMHC979", 0}, /* ARM CoreSight TPIU */
30 {"ARMHC97C", 0}, /* ARM CoreSight SoC-400 TMC, SoC-600 ETF/ETB */
31 {"ARMHC98D", 0}, /* ARM CoreSight Dynamic Replicator */
32 {"ARMHC9CA", 0}, /* ARM CoreSight CATU */
33 {"ARMHC9FF", 0}, /* ARM CoreSight Dynamic Funnel */
34 {"", 0},
35 };
36
amba_register_dummy_clk(void)37 static void amba_register_dummy_clk(void)
38 {
39 static struct clk *amba_dummy_clk;
40
41 /* If clock already registered */
42 if (amba_dummy_clk)
43 return;
44
45 amba_dummy_clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, 0, 0);
46 clk_register_clkdev(amba_dummy_clk, "apb_pclk", NULL);
47 }
48
amba_handler_attach(struct acpi_device * adev,const struct acpi_device_id * id)49 static int amba_handler_attach(struct acpi_device *adev,
50 const struct acpi_device_id *id)
51 {
52 struct acpi_device *parent = acpi_dev_parent(adev);
53 struct amba_device *dev;
54 struct resource_entry *rentry;
55 struct list_head resource_list;
56 bool address_found = false;
57 int irq_no = 0;
58 int ret;
59
60 /* If the ACPI node already has a physical device attached, skip it. */
61 if (adev->physical_node_count)
62 return 0;
63
64 dev = amba_device_alloc(dev_name(&adev->dev), 0, 0);
65 if (!dev) {
66 dev_err(&adev->dev, "%s(): amba_device_alloc() failed\n",
67 __func__);
68 return -ENOMEM;
69 }
70
71 INIT_LIST_HEAD(&resource_list);
72 ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
73 if (ret < 0)
74 goto err_free;
75
76 list_for_each_entry(rentry, &resource_list, node) {
77 switch (resource_type(rentry->res)) {
78 case IORESOURCE_MEM:
79 if (!address_found) {
80 dev->res = *rentry->res;
81 dev->res.name = dev_name(&dev->dev);
82 address_found = true;
83 }
84 break;
85 case IORESOURCE_IRQ:
86 if (irq_no < AMBA_NR_IRQS)
87 dev->irq[irq_no++] = rentry->res->start;
88 break;
89 default:
90 dev_warn(&adev->dev, "Invalid resource\n");
91 break;
92 }
93 }
94
95 acpi_dev_free_resource_list(&resource_list);
96
97 /*
98 * If the ACPI node has a parent and that parent has a physical device
99 * attached to it, that physical device should be the parent of
100 * the amba device we are about to create.
101 */
102 if (parent)
103 dev->dev.parent = acpi_get_first_physical_node(parent);
104
105 ACPI_COMPANION_SET(&dev->dev, adev);
106
107 ret = amba_device_add(dev, &iomem_resource);
108 if (ret) {
109 dev_err(&adev->dev, "%s(): amba_device_add() failed (%d)\n",
110 __func__, ret);
111 goto err_free;
112 }
113
114 return 1;
115
116 err_free:
117 amba_device_put(dev);
118 return ret;
119 }
120
121 static struct acpi_scan_handler amba_handler = {
122 .ids = amba_id_list,
123 .attach = amba_handler_attach,
124 };
125
acpi_amba_init(void)126 void __init acpi_amba_init(void)
127 {
128 amba_register_dummy_clk();
129 acpi_scan_add_handler(&amba_handler);
130 }
131
