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authorDave Airlie <airlied@redhat.com>2026-09-26 07:57:59 +1000
committerDave Airlie <airlied@redhat.com>2026-09-26 07:58:24 +1000
commita9ed3aa9b87ee41e8ab3ff471b1331c154767e45 (patch)
treecc62d74e0eb4905246978674461e78e2f9df2afd /drivers/cpufreq/freq_table.c
downloadlinux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.tar.gz
linux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.zip
Merge tag 'drm-misc-fixes-2026-09-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixesgrafted
A number of fixes: - bridge: - samsung-dsim: fix GPIO lifetime - client: Null pointer dereference fix - imagination: error handling fix, page handling fix - nouveau: fix reference leaks, double-frees, out-of-bounds accesses, use-after-frees, don't reject config without SCDC, a number of workarounds - virtio: fix memory leak, reference leaks, null pointer dereference, add pixel blend mode, cache coherency fix Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maxime Ripard <self@mripard.dev> Link: https://patch.msgid.link/arU22zzqUGDEco1y@houat
Diffstat (limited to 'drivers/cpufreq/freq_table.c')
-rw-r--r--drivers/cpufreq/freq_table.c370
1 files changed, 370 insertions, 0 deletions
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
new file mode 100644
index 000000000..ea994647a
--- /dev/null
+++ b/drivers/cpufreq/freq_table.c
@@ -0,0 +1,370 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/drivers/cpufreq/freq_table.c
+ *
+ * Copyright (C) 2002 - 2003 Dominik Brodowski
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+
+/*********************************************************************
+ * FREQUENCY TABLE HELPERS *
+ *********************************************************************/
+
+static bool policy_has_boost_freq(struct cpufreq_policy *policy)
+{
+ struct cpufreq_frequency_table *pos, *table = policy->freq_table;
+
+ if (!table)
+ return false;
+
+ cpufreq_for_each_valid_entry(pos, table)
+ if (pos->flags & CPUFREQ_BOOST_FREQ)
+ return true;
+
+ return false;
+}
+
+int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy)
+{
+ struct cpufreq_frequency_table *pos, *table = policy->freq_table;
+ unsigned int min_freq = ~0;
+ unsigned int max_freq = 0;
+ unsigned int freq, i;
+
+ cpufreq_for_each_valid_entry_idx(pos, table, i) {
+ freq = pos->frequency;
+
+ if ((!cpufreq_boost_enabled() || !policy->boost_enabled)
+ && (pos->flags & CPUFREQ_BOOST_FREQ))
+ continue;
+
+ pr_debug("table entry %u: %u kHz\n", i, freq);
+ if (freq < min_freq)
+ min_freq = freq;
+ if (freq > max_freq)
+ max_freq = freq;
+ }
+
+ policy->cpuinfo.min_freq = min_freq;
+ /*
+ * If the driver has set its own cpuinfo.max_freq above max_freq, leave
+ * it as is.
+ */
+ if (policy->cpuinfo.max_freq < max_freq)
+ policy->cpuinfo.max_freq = max_freq;
+
+ if (min_freq == ~0)
+ return -EINVAL;
+ else
+ return 0;
+}
+
+int cpufreq_frequency_table_verify(struct cpufreq_policy_data *policy)
+{
+ struct cpufreq_frequency_table *pos, *table = policy->freq_table;
+ unsigned int freq, prev_smaller = 0;
+ bool found = false;
+
+ pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
+ policy->min, policy->max, policy->cpu);
+
+ cpufreq_verify_within_cpu_limits(policy);
+
+ cpufreq_for_each_valid_entry(pos, table) {
+ freq = pos->frequency;
+
+ if ((freq >= policy->min) && (freq <= policy->max)) {
+ found = true;
+ break;
+ }
+
+ if ((prev_smaller < freq) && (freq <= policy->max))
+ prev_smaller = freq;
+ }
+
+ if (!found) {
+ policy->max = prev_smaller;
+ cpufreq_verify_within_cpu_limits(policy);
+ }
+
+ pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
+ policy->min, policy->max, policy->cpu);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
+
+/*
+ * Generic routine to verify policy & frequency table, requires driver to set
+ * policy->freq_table prior to it.
+ */
+int cpufreq_generic_frequency_table_verify(struct cpufreq_policy_data *policy)
+{
+ if (!policy->freq_table)
+ return -ENODEV;
+
+ return cpufreq_frequency_table_verify(policy);
+}
+EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
+
+int cpufreq_table_index_unsorted(struct cpufreq_policy *policy,
+ unsigned int target_freq, unsigned int min,
+ unsigned int max, unsigned int relation)
+{
+ struct cpufreq_frequency_table optimal = {
+ .driver_data = ~0,
+ .frequency = 0,
+ };
+ struct cpufreq_frequency_table suboptimal = {
+ .driver_data = ~0,
+ .frequency = 0,
+ };
+ struct cpufreq_frequency_table *pos;
+ struct cpufreq_frequency_table *table = policy->freq_table;
+ unsigned int freq, diff, i;
+ int index;
+
+ pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
+ target_freq, relation, policy->cpu);
+
+ switch (relation) {
+ case CPUFREQ_RELATION_H:
+ suboptimal.frequency = ~0;
+ break;
+ case CPUFREQ_RELATION_L:
+ case CPUFREQ_RELATION_C:
+ optimal.frequency = ~0;
+ break;
+ }
+
+ cpufreq_for_each_valid_entry_idx(pos, table, i) {
+ freq = pos->frequency;
+
+ if (freq < min || freq > max)
+ continue;
+ if (freq == target_freq) {
+ optimal.driver_data = i;
+ break;
+ }
+ switch (relation) {
+ case CPUFREQ_RELATION_H:
+ if (freq < target_freq) {
+ if (freq >= optimal.frequency) {
+ optimal.frequency = freq;
+ optimal.driver_data = i;
+ }
+ } else {
+ if (freq <= suboptimal.frequency) {
+ suboptimal.frequency = freq;
+ suboptimal.driver_data = i;
+ }
+ }
+ break;
+ case CPUFREQ_RELATION_L:
+ if (freq > target_freq) {
+ if (freq <= optimal.frequency) {
+ optimal.frequency = freq;
+ optimal.driver_data = i;
+ }
+ } else {
+ if (freq >= suboptimal.frequency) {
+ suboptimal.frequency = freq;
+ suboptimal.driver_data = i;
+ }
+ }
+ break;
+ case CPUFREQ_RELATION_C:
+ diff = abs(freq - target_freq);
+ if (diff < optimal.frequency ||
+ (diff == optimal.frequency &&
+ freq > table[optimal.driver_data].frequency)) {
+ optimal.frequency = diff;
+ optimal.driver_data = i;
+ }
+ break;
+ }
+ }
+ if (optimal.driver_data > i) {
+ if (suboptimal.driver_data > i) {
+ WARN(1, "Invalid frequency table: %u\n", policy->cpu);
+ return 0;
+ }
+
+ index = suboptimal.driver_data;
+ } else
+ index = optimal.driver_data;
+
+ pr_debug("target index is %u, freq is:%u kHz\n", index,
+ table[index].frequency);
+ return index;
+}
+EXPORT_SYMBOL_GPL(cpufreq_table_index_unsorted);
+
+int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
+ unsigned int freq)
+{
+ struct cpufreq_frequency_table *pos, *table = policy->freq_table;
+ int idx;
+
+ if (unlikely(!table)) {
+ pr_debug("%s: Unable to find frequency table\n", __func__);
+ return -ENOENT;
+ }
+
+ cpufreq_for_each_valid_entry_idx(pos, table, idx)
+ if (pos->frequency == freq)
+ return idx;
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);
+
+/*
+ * show_available_freqs - show available frequencies for the specified CPU
+ */
+static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
+ bool show_boost)
+{
+ ssize_t count = 0;
+ struct cpufreq_frequency_table *pos, *table = policy->freq_table;
+
+ if (!table)
+ return -ENODEV;
+
+ cpufreq_for_each_valid_entry(pos, table) {
+ /*
+ * show_boost = true and driver_data = BOOST freq
+ * display BOOST freqs
+ *
+ * show_boost = false and driver_data = BOOST freq
+ * show_boost = true and driver_data != BOOST freq
+ * continue - do not display anything
+ *
+ * show_boost = false and driver_data != BOOST freq
+ * display NON BOOST freqs
+ */
+ if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ))
+ continue;
+
+ count += sprintf(&buf[count], "%u ", pos->frequency);
+ }
+ count += sprintf(&buf[count], "\n");
+
+ return count;
+
+}
+
+#define cpufreq_attr_available_freq(_name) \
+struct freq_attr cpufreq_freq_attr_##_name##_freqs = \
+__ATTR_RO(_name##_frequencies)
+
+/*
+ * scaling_available_frequencies_show - show available normal frequencies for
+ * the specified CPU
+ */
+static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
+ char *buf)
+{
+ return show_available_freqs(policy, buf, false);
+}
+cpufreq_attr_available_freq(scaling_available);
+
+/*
+ * scaling_boost_frequencies_show - show available boost frequencies for
+ * the specified CPU
+ */
+static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,
+ char *buf)
+{
+ return show_available_freqs(policy, buf, true);
+}
+cpufreq_attr_available_freq(scaling_boost);
+
+static int set_freq_table_sorted(struct cpufreq_policy *policy)
+{
+ struct cpufreq_frequency_table *pos, *table = policy->freq_table;
+ struct cpufreq_frequency_table *prev = NULL;
+ int ascending = 0;
+
+ policy->freq_table_sorted = CPUFREQ_TABLE_UNSORTED;
+
+ cpufreq_for_each_valid_entry(pos, table) {
+ if (!prev) {
+ prev = pos;
+ continue;
+ }
+
+ if (pos->frequency == prev->frequency) {
+ pr_warn("Duplicate freq-table entries: %u\n",
+ pos->frequency);
+ return -EINVAL;
+ }
+
+ /* Frequency increased from prev to pos */
+ if (pos->frequency > prev->frequency) {
+ /* But frequency was decreasing earlier */
+ if (ascending < 0) {
+ pr_debug("Freq table is unsorted\n");
+ return 0;
+ }
+
+ ascending++;
+ } else {
+ /* Frequency decreased from prev to pos */
+
+ /* But frequency was increasing earlier */
+ if (ascending > 0) {
+ pr_debug("Freq table is unsorted\n");
+ return 0;
+ }
+
+ ascending--;
+ }
+
+ prev = pos;
+ }
+
+ if (ascending > 0)
+ policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_ASCENDING;
+ else
+ policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_DESCENDING;
+
+ pr_debug("Freq table is sorted in %s order\n",
+ ascending > 0 ? "ascending" : "descending");
+
+ return 0;
+}
+
+int cpufreq_table_validate_and_sort(struct cpufreq_policy *policy)
+{
+ int ret;
+
+ if (!policy->freq_table) {
+ /* Freq table must be passed by drivers with target_index() */
+ if (has_target_index())
+ return -EINVAL;
+
+ return 0;
+ }
+
+ ret = cpufreq_frequency_table_cpuinfo(policy);
+ if (ret)
+ return ret;
+
+ /* Driver's may have set this field already */
+ if (policy_has_boost_freq(policy))
+ policy->boost_supported = true;
+
+ if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING ||
+ policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_DESCENDING)
+ return 0;
+
+ return set_freq_table_sorted(policy);
+}
+
+MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
+MODULE_DESCRIPTION("CPUfreq frequency table helpers");