1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * ARM APMT table support. |
4 | * Design document number: ARM DEN0117. |
5 | * |
6 | * Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. |
7 | * |
8 | */ |
9 | |
10 | #define pr_fmt(fmt) "ACPI: APMT: " fmt |
11 | |
12 | #include <linux/acpi.h> |
13 | #include <linux/init.h> |
14 | #include <linux/kernel.h> |
15 | #include <linux/platform_device.h> |
16 | #include "init.h" |
17 | |
18 | #define DEV_NAME "arm-cs-arch-pmu" |
19 | |
20 | /* There can be up to 3 resources: page 0 and 1 address, and interrupt. */ |
21 | #define DEV_MAX_RESOURCE_COUNT 3 |
22 | |
23 | /* Root pointer to the mapped APMT table */ |
24 | static struct acpi_table_header *apmt_table; |
25 | |
26 | static int __init apmt_init_resources(struct resource *res, |
27 | struct acpi_apmt_node *node) |
28 | { |
29 | int irq, trigger; |
30 | int num_res = 0; |
31 | |
32 | res[num_res].start = node->base_address0; |
33 | res[num_res].end = node->base_address0 + SZ_4K - 1; |
34 | res[num_res].flags = IORESOURCE_MEM; |
35 | |
36 | num_res++; |
37 | |
38 | if (node->flags & ACPI_APMT_FLAGS_DUAL_PAGE) { |
39 | res[num_res].start = node->base_address1; |
40 | res[num_res].end = node->base_address1 + SZ_4K - 1; |
41 | res[num_res].flags = IORESOURCE_MEM; |
42 | |
43 | num_res++; |
44 | } |
45 | |
46 | if (node->ovflw_irq != 0) { |
47 | trigger = (node->ovflw_irq_flags & ACPI_APMT_OVFLW_IRQ_FLAGS_MODE); |
48 | trigger = (trigger == ACPI_APMT_OVFLW_IRQ_FLAGS_MODE_LEVEL) ? |
49 | ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE; |
50 | irq = acpi_register_gsi(NULL, gsi: node->ovflw_irq, triggering: trigger, |
51 | ACPI_ACTIVE_HIGH); |
52 | |
53 | if (irq <= 0) { |
54 | pr_warn("APMT could not register gsi hwirq %d\n" , irq); |
55 | return num_res; |
56 | } |
57 | |
58 | res[num_res].start = irq; |
59 | res[num_res].end = irq; |
60 | res[num_res].flags = IORESOURCE_IRQ; |
61 | |
62 | num_res++; |
63 | } |
64 | |
65 | return num_res; |
66 | } |
67 | |
68 | /** |
69 | * apmt_add_platform_device() - Allocate a platform device for APMT node |
70 | * @node: Pointer to device ACPI APMT node |
71 | * @fwnode: fwnode associated with the APMT node |
72 | * |
73 | * Returns: 0 on success, <0 failure |
74 | */ |
75 | static int __init apmt_add_platform_device(struct acpi_apmt_node *node, |
76 | struct fwnode_handle *fwnode) |
77 | { |
78 | struct platform_device *pdev; |
79 | int ret, count; |
80 | struct resource res[DEV_MAX_RESOURCE_COUNT]; |
81 | |
82 | pdev = platform_device_alloc(DEV_NAME, PLATFORM_DEVID_AUTO); |
83 | if (!pdev) |
84 | return -ENOMEM; |
85 | |
86 | memset(res, 0, sizeof(res)); |
87 | |
88 | count = apmt_init_resources(res, node); |
89 | |
90 | ret = platform_device_add_resources(pdev, res, num: count); |
91 | if (ret) |
92 | goto dev_put; |
93 | |
94 | /* |
95 | * Add a copy of APMT node pointer to platform_data to be used to |
96 | * retrieve APMT data information. |
97 | */ |
98 | ret = platform_device_add_data(pdev, data: &node, size: sizeof(node)); |
99 | if (ret) |
100 | goto dev_put; |
101 | |
102 | pdev->dev.fwnode = fwnode; |
103 | |
104 | ret = platform_device_add(pdev); |
105 | |
106 | if (ret) |
107 | goto dev_put; |
108 | |
109 | return 0; |
110 | |
111 | dev_put: |
112 | platform_device_put(pdev); |
113 | |
114 | return ret; |
115 | } |
116 | |
117 | static int __init apmt_init_platform_devices(void) |
118 | { |
119 | struct acpi_apmt_node *apmt_node; |
120 | struct acpi_table_apmt *apmt; |
121 | struct fwnode_handle *fwnode; |
122 | u64 offset, end; |
123 | int ret; |
124 | |
125 | /* |
126 | * apmt_table and apmt both point to the start of APMT table, but |
127 | * have different struct types |
128 | */ |
129 | apmt = (struct acpi_table_apmt *)apmt_table; |
130 | offset = sizeof(*apmt); |
131 | end = apmt->header.length; |
132 | |
133 | while (offset < end) { |
134 | apmt_node = ACPI_ADD_PTR(struct acpi_apmt_node, apmt, |
135 | offset); |
136 | |
137 | fwnode = acpi_alloc_fwnode_static(); |
138 | if (!fwnode) |
139 | return -ENOMEM; |
140 | |
141 | ret = apmt_add_platform_device(node: apmt_node, fwnode); |
142 | if (ret) { |
143 | acpi_free_fwnode_static(fwnode); |
144 | return ret; |
145 | } |
146 | |
147 | offset += apmt_node->length; |
148 | } |
149 | |
150 | return 0; |
151 | } |
152 | |
153 | void __init acpi_apmt_init(void) |
154 | { |
155 | acpi_status status; |
156 | int ret; |
157 | |
158 | /** |
159 | * APMT table nodes will be used at runtime after the apmt init, |
160 | * so we don't need to call acpi_put_table() to release |
161 | * the APMT table mapping. |
162 | */ |
163 | status = acpi_get_table(ACPI_SIG_APMT, instance: 0, out_table: &apmt_table); |
164 | |
165 | if (ACPI_FAILURE(status)) { |
166 | if (status != AE_NOT_FOUND) { |
167 | const char *msg = acpi_format_exception(exception: status); |
168 | |
169 | pr_err("Failed to get APMT table, %s\n" , msg); |
170 | } |
171 | |
172 | return; |
173 | } |
174 | |
175 | ret = apmt_init_platform_devices(); |
176 | if (ret) { |
177 | pr_err("Failed to initialize APMT platform devices, ret: %d\n" , ret); |
178 | acpi_put_table(table: apmt_table); |
179 | } |
180 | } |
181 | |