1 // SPDX-License-Identifier: GPL-2.0
2 
3 /*
4  * Intel PMC Core platform init
5  * Copyright (c) 2019, Google Inc.
6  * Author - Rajat Jain
7  *
8  * This code instantiates platform devices for intel_pmc_core driver, only
9  * on supported platforms that may not have the ACPI devices in the ACPI tables.
10  * No new platforms should be added here, because we expect that new platforms
11  * should all have the ACPI device, which is the preferred way of enumeration.
12  */
13 
14 #include <linux/acpi.h>
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 
18 #include <asm/cpu_device_id.h>
19 #include <asm/intel-family.h>
20 
21 static void intel_pmc_core_release(struct device *dev)
22 {
23 	kfree(dev);
24 }
25 
26 static struct platform_device *pmc_core_device;
27 
28 /*
29  * intel_pmc_core_platform_ids is the list of platforms where we want to
30  * instantiate the platform_device if not already instantiated. This is
31  * different than intel_pmc_core_ids in intel_pmc_core.c which is the
32  * list of platforms that the driver supports for pmc_core device. The
33  * other list may grow, but this list should not.
34  */
35 static const struct x86_cpu_id intel_pmc_core_platform_ids[] = {
36 	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L,		&pmc_core_device),
37 	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE,		&pmc_core_device),
38 	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L,		&pmc_core_device),
39 	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE,		&pmc_core_device),
40 	X86_MATCH_INTEL_FAM6_MODEL(CANNONLAKE_L,	&pmc_core_device),
41 	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_L,		&pmc_core_device),
42 	X86_MATCH_INTEL_FAM6_MODEL(COMETLAKE,		&pmc_core_device),
43 	X86_MATCH_INTEL_FAM6_MODEL(COMETLAKE_L,		&pmc_core_device),
44 	{}
45 };
46 MODULE_DEVICE_TABLE(x86cpu, intel_pmc_core_platform_ids);
47 
48 static int __init pmc_core_platform_init(void)
49 {
50 	int retval;
51 
52 	/* Skip creating the platform device if ACPI already has a device */
53 	if (acpi_dev_present("INT33A1", NULL, -1))
54 		return -ENODEV;
55 
56 	if (!x86_match_cpu(intel_pmc_core_platform_ids))
57 		return -ENODEV;
58 
59 	pmc_core_device = kzalloc(sizeof(*pmc_core_device), GFP_KERNEL);
60 	if (!pmc_core_device)
61 		return -ENOMEM;
62 
63 	pmc_core_device->name = "intel_pmc_core";
64 	pmc_core_device->dev.release = intel_pmc_core_release;
65 
66 	retval = platform_device_register(pmc_core_device);
67 	if (retval)
68 		kfree(pmc_core_device);
69 
70 	return retval;
71 }
72 
73 static void __exit pmc_core_platform_exit(void)
74 {
75 	platform_device_unregister(pmc_core_device);
76 }
77 
78 module_init(pmc_core_platform_init);
79 module_exit(pmc_core_platform_exit);
80 MODULE_LICENSE("GPL v2");
81