linux/drivers/cpufreq/sfi-cpufreq.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* SFI Performance States Driver
*
* Author: Vishwesh M Rudramuni <vishwesh.m.rudramuni@intel.com>
* Author: Srinidhi Kasagar <srinidhi.kasagar@intel.com>
*/
#include <linux/cpufreq.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sfi.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <asm/msr.h>
static struct cpufreq_frequency_table *freq_table;
static struct sfi_freq_table_entry *sfi_cpufreq_array;
static int num_freq_table_entries;
static int sfi_parse_freq(struct sfi_table_header *table)
{
struct sfi_table_simple *sb;
struct sfi_freq_table_entry *pentry;
int totallen;
sb = (struct sfi_table_simple *)table;
num_freq_table_entries = SFI_GET_NUM_ENTRIES(sb,
struct sfi_freq_table_entry);
if (num_freq_table_entries <= 1) {
pr_err("No p-states discovered\n");
return -ENODEV;
}
pentry = (struct sfi_freq_table_entry *)sb->pentry;
totallen = num_freq_table_entries * sizeof(*pentry);
sfi_cpufreq_array = kmemdup(pentry, totallen, GFP_KERNEL);
if (!sfi_cpufreq_array)
return -ENOMEM;
return 0;
}
static int sfi_cpufreq_target(struct cpufreq_policy *policy, unsigned int index)
{
unsigned int next_perf_state = 0; /* Index into perf table */
u32 lo, hi;
next_perf_state = policy->freq_table[index].driver_data;
rdmsr_on_cpu(policy->cpu, MSR_IA32_PERF_CTL, &lo, &hi);
lo = (lo & ~INTEL_PERF_CTL_MASK) |
((u32) sfi_cpufreq_array[next_perf_state].ctrl_val &
INTEL_PERF_CTL_MASK);
wrmsr_on_cpu(policy->cpu, MSR_IA32_PERF_CTL, lo, hi);
return 0;
}
static int sfi_cpufreq_cpu_init(struct cpufreq_policy *policy)
{
policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
policy->cpuinfo.transition_latency = 100000; /* 100us */
policy->freq_table = freq_table;
return 0;
}
static struct cpufreq_driver sfi_cpufreq_driver = {
.flags = CPUFREQ_CONST_LOOPS,
.verify = cpufreq_generic_frequency_table_verify,
.target_index = sfi_cpufreq_target,
.init = sfi_cpufreq_cpu_init,
.name = "sfi-cpufreq",
.attr = cpufreq_generic_attr,
};
static int __init sfi_cpufreq_init(void)
{
int ret, i;
/* parse the freq table from SFI */
ret = sfi_table_parse(SFI_SIG_FREQ, NULL, NULL, sfi_parse_freq);
if (ret)
return ret;
treewide: kzalloc() -> kcalloc() The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 21:03:40 +00:00
freq_table = kcalloc(num_freq_table_entries + 1, sizeof(*freq_table),
GFP_KERNEL);
if (!freq_table) {
ret = -ENOMEM;
goto err_free_array;
}
for (i = 0; i < num_freq_table_entries; i++) {
freq_table[i].driver_data = i;
freq_table[i].frequency = sfi_cpufreq_array[i].freq_mhz * 1000;
}
freq_table[i].frequency = CPUFREQ_TABLE_END;
ret = cpufreq_register_driver(&sfi_cpufreq_driver);
if (ret)
goto err_free_tbl;
return ret;
err_free_tbl:
kfree(freq_table);
err_free_array:
kfree(sfi_cpufreq_array);
return ret;
}
late_initcall(sfi_cpufreq_init);
static void __exit sfi_cpufreq_exit(void)
{
cpufreq_unregister_driver(&sfi_cpufreq_driver);
kfree(freq_table);
kfree(sfi_cpufreq_array);
}
module_exit(sfi_cpufreq_exit);
MODULE_AUTHOR("Vishwesh M Rudramuni <vishwesh.m.rudramuni@intel.com>");
MODULE_DESCRIPTION("SFI Performance-States Driver");
MODULE_LICENSE("GPL");