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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cacheinfo.c (5201B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Copyright (C) 2017 SiFive
      4 */
      5
      6#include <linux/cpu.h>
      7#include <linux/of.h>
      8#include <linux/of_device.h>
      9#include <asm/cacheinfo.h>
     10
     11static struct riscv_cacheinfo_ops *rv_cache_ops;
     12
     13void riscv_set_cacheinfo_ops(struct riscv_cacheinfo_ops *ops)
     14{
     15	rv_cache_ops = ops;
     16}
     17EXPORT_SYMBOL_GPL(riscv_set_cacheinfo_ops);
     18
     19const struct attribute_group *
     20cache_get_priv_group(struct cacheinfo *this_leaf)
     21{
     22	if (rv_cache_ops && rv_cache_ops->get_priv_group)
     23		return rv_cache_ops->get_priv_group(this_leaf);
     24	return NULL;
     25}
     26
     27static struct cacheinfo *get_cacheinfo(u32 level, enum cache_type type)
     28{
     29	/*
     30	 * Using raw_smp_processor_id() elides a preemptability check, but this
     31	 * is really indicative of a larger problem: the cacheinfo UABI assumes
     32	 * that cores have a homonogenous view of the cache hierarchy.  That
     33	 * happens to be the case for the current set of RISC-V systems, but
     34	 * likely won't be true in general.  Since there's no way to provide
     35	 * correct information for these systems via the current UABI we're
     36	 * just eliding the check for now.
     37	 */
     38	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(raw_smp_processor_id());
     39	struct cacheinfo *this_leaf;
     40	int index;
     41
     42	for (index = 0; index < this_cpu_ci->num_leaves; index++) {
     43		this_leaf = this_cpu_ci->info_list + index;
     44		if (this_leaf->level == level && this_leaf->type == type)
     45			return this_leaf;
     46	}
     47
     48	return NULL;
     49}
     50
     51uintptr_t get_cache_size(u32 level, enum cache_type type)
     52{
     53	struct cacheinfo *this_leaf = get_cacheinfo(level, type);
     54
     55	return this_leaf ? this_leaf->size : 0;
     56}
     57
     58uintptr_t get_cache_geometry(u32 level, enum cache_type type)
     59{
     60	struct cacheinfo *this_leaf = get_cacheinfo(level, type);
     61
     62	return this_leaf ? (this_leaf->ways_of_associativity << 16 |
     63			    this_leaf->coherency_line_size) :
     64			   0;
     65}
     66
     67static void ci_leaf_init(struct cacheinfo *this_leaf, enum cache_type type,
     68			 unsigned int level, unsigned int size,
     69			 unsigned int sets, unsigned int line_size)
     70{
     71	this_leaf->level = level;
     72	this_leaf->type = type;
     73	this_leaf->size = size;
     74	this_leaf->number_of_sets = sets;
     75	this_leaf->coherency_line_size = line_size;
     76
     77	/*
     78	 * If the cache is fully associative, there is no need to
     79	 * check the other properties.
     80	 */
     81	if (sets == 1)
     82		return;
     83
     84	/*
     85	 * Set the ways number for n-ways associative, make sure
     86	 * all properties are big than zero.
     87	 */
     88	if (sets > 0 && size > 0 && line_size > 0)
     89		this_leaf->ways_of_associativity = (size / sets) / line_size;
     90}
     91
     92static void fill_cacheinfo(struct cacheinfo **this_leaf,
     93			   struct device_node *node, unsigned int level)
     94{
     95	unsigned int size, sets, line_size;
     96
     97	if (!of_property_read_u32(node, "cache-size", &size) &&
     98	    !of_property_read_u32(node, "cache-block-size", &line_size) &&
     99	    !of_property_read_u32(node, "cache-sets", &sets)) {
    100		ci_leaf_init((*this_leaf)++, CACHE_TYPE_UNIFIED, level, size, sets, line_size);
    101	}
    102
    103	if (!of_property_read_u32(node, "i-cache-size", &size) &&
    104	    !of_property_read_u32(node, "i-cache-sets", &sets) &&
    105	    !of_property_read_u32(node, "i-cache-block-size", &line_size)) {
    106		ci_leaf_init((*this_leaf)++, CACHE_TYPE_INST, level, size, sets, line_size);
    107	}
    108
    109	if (!of_property_read_u32(node, "d-cache-size", &size) &&
    110	    !of_property_read_u32(node, "d-cache-sets", &sets) &&
    111	    !of_property_read_u32(node, "d-cache-block-size", &line_size)) {
    112		ci_leaf_init((*this_leaf)++, CACHE_TYPE_DATA, level, size, sets, line_size);
    113	}
    114}
    115
    116int init_cache_level(unsigned int cpu)
    117{
    118	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
    119	struct device_node *np = of_cpu_device_node_get(cpu);
    120	struct device_node *prev = NULL;
    121	int levels = 0, leaves = 0, level;
    122
    123	if (of_property_read_bool(np, "cache-size"))
    124		++leaves;
    125	if (of_property_read_bool(np, "i-cache-size"))
    126		++leaves;
    127	if (of_property_read_bool(np, "d-cache-size"))
    128		++leaves;
    129	if (leaves > 0)
    130		levels = 1;
    131
    132	prev = np;
    133	while ((np = of_find_next_cache_node(np))) {
    134		of_node_put(prev);
    135		prev = np;
    136		if (!of_device_is_compatible(np, "cache"))
    137			break;
    138		if (of_property_read_u32(np, "cache-level", &level))
    139			break;
    140		if (level <= levels)
    141			break;
    142		if (of_property_read_bool(np, "cache-size"))
    143			++leaves;
    144		if (of_property_read_bool(np, "i-cache-size"))
    145			++leaves;
    146		if (of_property_read_bool(np, "d-cache-size"))
    147			++leaves;
    148		levels = level;
    149	}
    150
    151	of_node_put(np);
    152	this_cpu_ci->num_levels = levels;
    153	this_cpu_ci->num_leaves = leaves;
    154
    155	return 0;
    156}
    157
    158int populate_cache_leaves(unsigned int cpu)
    159{
    160	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
    161	struct cacheinfo *this_leaf = this_cpu_ci->info_list;
    162	struct device_node *np = of_cpu_device_node_get(cpu);
    163	struct device_node *prev = NULL;
    164	int levels = 1, level = 1;
    165
    166	/* Level 1 caches in cpu node */
    167	fill_cacheinfo(&this_leaf, np, level);
    168
    169	/* Next level caches in cache nodes */
    170	prev = np;
    171	while ((np = of_find_next_cache_node(np))) {
    172		of_node_put(prev);
    173		prev = np;
    174
    175		if (!of_device_is_compatible(np, "cache"))
    176			break;
    177		if (of_property_read_u32(np, "cache-level", &level))
    178			break;
    179		if (level <= levels)
    180			break;
    181
    182		fill_cacheinfo(&this_leaf, np, level);
    183
    184		levels = level;
    185	}
    186	of_node_put(np);
    187
    188	return 0;
    189}