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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irq-gic-v3-its-platform-msi.c (3868B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Copyright (C) 2013-2015 ARM Limited, All Rights Reserved.
      4 * Author: Marc Zyngier <marc.zyngier@arm.com>
      5 */
      6
      7#include <linux/acpi_iort.h>
      8#include <linux/device.h>
      9#include <linux/msi.h>
     10#include <linux/of.h>
     11#include <linux/of_irq.h>
     12
     13static struct irq_chip its_pmsi_irq_chip = {
     14	.name			= "ITS-pMSI",
     15};
     16
     17static int of_pmsi_get_dev_id(struct irq_domain *domain, struct device *dev,
     18				  u32 *dev_id)
     19{
     20	int ret, index = 0;
     21
     22	/* Suck the DeviceID out of the msi-parent property */
     23	do {
     24		struct of_phandle_args args;
     25
     26		ret = of_parse_phandle_with_args(dev->of_node,
     27						 "msi-parent", "#msi-cells",
     28						 index, &args);
     29		if (args.np == irq_domain_get_of_node(domain)) {
     30			if (WARN_ON(args.args_count != 1))
     31				return -EINVAL;
     32			*dev_id = args.args[0];
     33			break;
     34		}
     35		index++;
     36	} while (!ret);
     37
     38	return ret;
     39}
     40
     41int __weak iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id)
     42{
     43	return -1;
     44}
     45
     46static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
     47			    int nvec, msi_alloc_info_t *info)
     48{
     49	struct msi_domain_info *msi_info;
     50	u32 dev_id;
     51	int ret;
     52
     53	msi_info = msi_get_domain_info(domain->parent);
     54
     55	if (dev->of_node)
     56		ret = of_pmsi_get_dev_id(domain, dev, &dev_id);
     57	else
     58		ret = iort_pmsi_get_dev_id(dev, &dev_id);
     59	if (ret)
     60		return ret;
     61
     62	/* ITS specific DeviceID, as the core ITS ignores dev. */
     63	info->scratchpad[0].ul = dev_id;
     64
     65	/* Allocate at least 32 MSIs, and always as a power of 2 */
     66	nvec = max_t(int, 32, roundup_pow_of_two(nvec));
     67	return msi_info->ops->msi_prepare(domain->parent,
     68					  dev, nvec, info);
     69}
     70
     71static struct msi_domain_ops its_pmsi_ops = {
     72	.msi_prepare	= its_pmsi_prepare,
     73};
     74
     75static struct msi_domain_info its_pmsi_domain_info = {
     76	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
     77	.ops	= &its_pmsi_ops,
     78	.chip	= &its_pmsi_irq_chip,
     79};
     80
     81static const struct of_device_id its_device_id[] = {
     82	{	.compatible	= "arm,gic-v3-its",	},
     83	{},
     84};
     85
     86static int __init its_pmsi_init_one(struct fwnode_handle *fwnode,
     87				const char *name)
     88{
     89	struct irq_domain *parent;
     90
     91	parent = irq_find_matching_fwnode(fwnode, DOMAIN_BUS_NEXUS);
     92	if (!parent || !msi_get_domain_info(parent)) {
     93		pr_err("%s: unable to locate ITS domain\n", name);
     94		return -ENXIO;
     95	}
     96
     97	if (!platform_msi_create_irq_domain(fwnode, &its_pmsi_domain_info,
     98					    parent)) {
     99		pr_err("%s: unable to create platform domain\n", name);
    100		return -ENXIO;
    101	}
    102
    103	pr_info("Platform MSI: %s domain created\n", name);
    104	return 0;
    105}
    106
    107#ifdef CONFIG_ACPI
    108static int __init
    109its_pmsi_parse_madt(union acpi_subtable_headers *header,
    110			const unsigned long end)
    111{
    112	struct acpi_madt_generic_translator *its_entry;
    113	struct fwnode_handle *domain_handle;
    114	const char *node_name;
    115	int err = -ENXIO;
    116
    117	its_entry = (struct acpi_madt_generic_translator *)header;
    118	node_name = kasprintf(GFP_KERNEL, "ITS@0x%lx",
    119			      (long)its_entry->base_address);
    120	domain_handle = iort_find_domain_token(its_entry->translation_id);
    121	if (!domain_handle) {
    122		pr_err("%s: Unable to locate ITS domain handle\n", node_name);
    123		goto out;
    124	}
    125
    126	err = its_pmsi_init_one(domain_handle, node_name);
    127
    128out:
    129	kfree(node_name);
    130	return err;
    131}
    132
    133static void __init its_pmsi_acpi_init(void)
    134{
    135	acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_TRANSLATOR,
    136			      its_pmsi_parse_madt, 0);
    137}
    138#else
    139static inline void its_pmsi_acpi_init(void) { }
    140#endif
    141
    142static void __init its_pmsi_of_init(void)
    143{
    144	struct device_node *np;
    145
    146	for (np = of_find_matching_node(NULL, its_device_id); np;
    147	     np = of_find_matching_node(np, its_device_id)) {
    148		if (!of_device_is_available(np))
    149			continue;
    150		if (!of_property_read_bool(np, "msi-controller"))
    151			continue;
    152
    153		its_pmsi_init_one(of_node_to_fwnode(np), np->full_name);
    154	}
    155}
    156
    157static int __init its_pmsi_init(void)
    158{
    159	its_pmsi_of_init();
    160	its_pmsi_acpi_init();
    161	return 0;
    162}
    163early_initcall(its_pmsi_init);