cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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acpi_platform.c (4873B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * ACPI support for platform bus type.
      4 *
      5 * Copyright (C) 2012, Intel Corporation
      6 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
      7 *          Mathias Nyman <mathias.nyman@linux.intel.com>
      8 *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
      9 */
     10
     11#include <linux/acpi.h>
     12#include <linux/device.h>
     13#include <linux/err.h>
     14#include <linux/kernel.h>
     15#include <linux/module.h>
     16#include <linux/dma-mapping.h>
     17#include <linux/pci.h>
     18#include <linux/platform_device.h>
     19
     20#include "internal.h"
     21
     22static const struct acpi_device_id forbidden_id_list[] = {
     23	{"PNP0000",  0},	/* PIC */
     24	{"PNP0100",  0},	/* Timer */
     25	{"PNP0200",  0},	/* AT DMA Controller */
     26	{"ACPI0009", 0},	/* IOxAPIC */
     27	{"ACPI000A", 0},	/* IOAPIC */
     28	{"SMB0001",  0},	/* ACPI SMBUS virtual device */
     29	{"", 0},
     30};
     31
     32static struct platform_device *acpi_platform_device_find_by_companion(struct acpi_device *adev)
     33{
     34	struct device *dev;
     35
     36	dev = bus_find_device_by_acpi_dev(&platform_bus_type, adev);
     37	return dev ? to_platform_device(dev) : NULL;
     38}
     39
     40static int acpi_platform_device_remove_notify(struct notifier_block *nb,
     41					      unsigned long value, void *arg)
     42{
     43	struct acpi_device *adev = arg;
     44	struct platform_device *pdev;
     45
     46	switch (value) {
     47	case ACPI_RECONFIG_DEVICE_ADD:
     48		/* Nothing to do here */
     49		break;
     50	case ACPI_RECONFIG_DEVICE_REMOVE:
     51		if (!acpi_device_enumerated(adev))
     52			break;
     53
     54		pdev = acpi_platform_device_find_by_companion(adev);
     55		if (!pdev)
     56			break;
     57
     58		platform_device_unregister(pdev);
     59		put_device(&pdev->dev);
     60		break;
     61	}
     62
     63	return NOTIFY_OK;
     64}
     65
     66static struct notifier_block acpi_platform_notifier = {
     67	.notifier_call = acpi_platform_device_remove_notify,
     68};
     69
     70static void acpi_platform_fill_resource(struct acpi_device *adev,
     71	const struct resource *src, struct resource *dest)
     72{
     73	struct device *parent;
     74
     75	*dest = *src;
     76
     77	/*
     78	 * If the device has parent we need to take its resources into
     79	 * account as well because this device might consume part of those.
     80	 */
     81	parent = acpi_get_first_physical_node(adev->parent);
     82	if (parent && dev_is_pci(parent))
     83		dest->parent = pci_find_resource(to_pci_dev(parent), dest);
     84}
     85
     86/**
     87 * acpi_create_platform_device - Create platform device for ACPI device node
     88 * @adev: ACPI device node to create a platform device for.
     89 * @properties: Optional collection of build-in properties.
     90 *
     91 * Check if the given @adev can be represented as a platform device and, if
     92 * that's the case, create and register a platform device, populate its common
     93 * resources and returns a pointer to it.  Otherwise, return %NULL.
     94 *
     95 * Name of the platform device will be the same as @adev's.
     96 */
     97struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
     98						    const struct property_entry *properties)
     99{
    100	struct platform_device *pdev = NULL;
    101	struct platform_device_info pdevinfo;
    102	struct resource_entry *rentry;
    103	struct list_head resource_list;
    104	struct resource *resources = NULL;
    105	int count;
    106
    107	/* If the ACPI node already has a physical device attached, skip it. */
    108	if (adev->physical_node_count)
    109		return NULL;
    110
    111	if (!acpi_match_device_ids(adev, forbidden_id_list))
    112		return ERR_PTR(-EINVAL);
    113
    114	INIT_LIST_HEAD(&resource_list);
    115	count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
    116	if (count < 0) {
    117		return NULL;
    118	} else if (count > 0) {
    119		resources = kcalloc(count, sizeof(struct resource),
    120				    GFP_KERNEL);
    121		if (!resources) {
    122			dev_err(&adev->dev, "No memory for resources\n");
    123			acpi_dev_free_resource_list(&resource_list);
    124			return ERR_PTR(-ENOMEM);
    125		}
    126		count = 0;
    127		list_for_each_entry(rentry, &resource_list, node)
    128			acpi_platform_fill_resource(adev, rentry->res,
    129						    &resources[count++]);
    130
    131		acpi_dev_free_resource_list(&resource_list);
    132	}
    133
    134	memset(&pdevinfo, 0, sizeof(pdevinfo));
    135	/*
    136	 * If the ACPI node has a parent and that parent has a physical device
    137	 * attached to it, that physical device should be the parent of the
    138	 * platform device we are about to create.
    139	 */
    140	pdevinfo.parent = adev->parent ?
    141		acpi_get_first_physical_node(adev->parent) : NULL;
    142	pdevinfo.name = dev_name(&adev->dev);
    143	pdevinfo.id = -1;
    144	pdevinfo.res = resources;
    145	pdevinfo.num_res = count;
    146	pdevinfo.fwnode = acpi_fwnode_handle(adev);
    147	pdevinfo.properties = properties;
    148
    149	if (acpi_dma_supported(adev))
    150		pdevinfo.dma_mask = DMA_BIT_MASK(32);
    151	else
    152		pdevinfo.dma_mask = 0;
    153
    154	pdev = platform_device_register_full(&pdevinfo);
    155	if (IS_ERR(pdev))
    156		dev_err(&adev->dev, "platform device creation failed: %ld\n",
    157			PTR_ERR(pdev));
    158	else {
    159		set_dev_node(&pdev->dev, acpi_get_node(adev->handle));
    160		dev_dbg(&adev->dev, "created platform device %s\n",
    161			dev_name(&pdev->dev));
    162	}
    163
    164	kfree(resources);
    165
    166	return pdev;
    167}
    168EXPORT_SYMBOL_GPL(acpi_create_platform_device);
    169
    170void __init acpi_platform_init(void)
    171{
    172	acpi_reconfig_notifier_register(&acpi_platform_notifier);
    173}