cpufreq drivers aren't required to provide a sorted frequency table today, and even the ones which provide a sorted table aren't handled efficiently by cpufreq core.
This patch adds infrastructure to verify if the freq-table provided by the drivers is sorted or not, and use efficient helpers if they are sorted.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- Thanks to Francesco for spotting few wrong comments and a statement in V5. They are fixed now.
drivers/cpufreq/freq_table.c | 73 ++++++++++++-- include/linux/cpufreq.h | 234 ++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 296 insertions(+), 11 deletions(-)
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c index eac8bcbdaad1..3bbbf9e6960c 100644 --- a/drivers/cpufreq/freq_table.c +++ b/drivers/cpufreq/freq_table.c @@ -113,9 +113,9 @@ int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy) } EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
-int cpufreq_frequency_table_target(struct cpufreq_policy *policy, - unsigned int target_freq, - unsigned int relation) +int cpufreq_table_index_unsorted(struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation) { struct cpufreq_frequency_table optimal = { .driver_data = ~0, @@ -205,7 +205,7 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy, table[index].frequency); return index; } -EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target); +EXPORT_SYMBOL_GPL(cpufreq_table_index_unsorted);
int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, unsigned int freq) @@ -297,15 +297,72 @@ struct freq_attr *cpufreq_generic_attr[] = { }; EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
+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_show(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table) { - int ret = cpufreq_frequency_table_cpuinfo(policy, table); + int ret;
- if (!ret) - policy->freq_table = table; + ret = cpufreq_frequency_table_cpuinfo(policy, table); + if (ret) + return ret;
- return ret; + policy->freq_table = table; + return set_freq_table_sorted(policy); } EXPORT_SYMBOL_GPL(cpufreq_table_validate_and_show);
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index c378776628b4..c6410b1b2490 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -36,6 +36,12 @@
struct cpufreq_governor;
+enum cpufreq_table_sorting { + CPUFREQ_TABLE_UNSORTED, + CPUFREQ_TABLE_SORTED_ASCENDING, + CPUFREQ_TABLE_SORTED_DESCENDING +}; + struct cpufreq_freqs { unsigned int cpu; /* cpu nr */ unsigned int old; @@ -87,6 +93,7 @@ struct cpufreq_policy {
struct cpufreq_user_policy user_policy; struct cpufreq_frequency_table *freq_table; + enum cpufreq_table_sorting freq_table_sorted;
struct list_head policy_list; struct kobject kobj; @@ -597,9 +604,9 @@ int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table); int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy);
-int cpufreq_frequency_table_target(struct cpufreq_policy *policy, - unsigned int target_freq, - unsigned int relation); +int cpufreq_table_index_unsorted(struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation); int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, unsigned int freq);
@@ -610,6 +617,227 @@ int cpufreq_boost_trigger_state(int state); int cpufreq_boost_enabled(void); int cpufreq_enable_boost_support(void); bool policy_has_boost_freq(struct cpufreq_policy *policy); + +/* Find lowest freq at or above target in a table in ascending order */ +static inline int cpufreq_table_find_index_al(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq >= target_freq) + return i; + + best = i; + } + + return best; +} + +/* Find lowest freq at or above target in a table in descending order */ +static inline int cpufreq_table_find_index_dl(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq == target_freq) + return i; + + if (freq > target_freq) { + best = i; + continue; + } + + /* No freq found above target_freq */ + if (best == -1) + return i; + + return best; + } + + return best; +} + +/* Works only on sorted freq-tables */ +static inline int cpufreq_table_find_index_l(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + target_freq = clamp_val(target_freq, policy->min, policy->max); + + if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING) + return cpufreq_table_find_index_al(policy, target_freq); + else + return cpufreq_table_find_index_dl(policy, target_freq); +} + +/* Find highest freq at or below target in a table in ascending order */ +static inline int cpufreq_table_find_index_ah(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq == target_freq) + return i; + + if (freq < target_freq) { + best = i; + continue; + } + + /* No freq found below target_freq */ + if (best == -1) + return i; + + return best; + } + + return best; +} + +/* Find highest freq at or below target in a table in descending order */ +static inline int cpufreq_table_find_index_dh(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq <= target_freq) + return i; + + best = i; + } + + return best; +} + +/* Works only on sorted freq-tables */ +static inline int cpufreq_table_find_index_h(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + target_freq = clamp_val(target_freq, policy->min, policy->max); + + if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING) + return cpufreq_table_find_index_ah(policy, target_freq); + else + return cpufreq_table_find_index_dh(policy, target_freq); +} + +/* Find closest freq to target in a table in ascending order */ +static inline int cpufreq_table_find_index_ac(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq == target_freq) + return i; + + if (freq < target_freq) { + best = i; + continue; + } + + /* No freq found below target_freq */ + if (best == -1) + return i; + + /* Choose the closest freq */ + if (target_freq - table[best].frequency > freq - target_freq) + return i; + + return best; + } + + return best; +} + +/* Find closest freq to target in a table in descending order */ +static inline int cpufreq_table_find_index_dc(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq == target_freq) + return i; + + if (freq > target_freq) { + best = i; + continue; + } + + /* No freq found above target_freq */ + if (best == -1) + return i; + + /* Choose the closest freq */ + if (table[best].frequency - target_freq > target_freq - freq) + return i; + + return best; + } + + return best; +} + +/* Works only on sorted freq-tables */ +static inline int cpufreq_table_find_index_c(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + target_freq = clamp_val(target_freq, policy->min, policy->max); + + if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING) + return cpufreq_table_find_index_ac(policy, target_freq); + else + return cpufreq_table_find_index_dc(policy, target_freq); +} + +static inline int cpufreq_frequency_table_target(struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation) +{ + if (unlikely(policy->freq_table_sorted == CPUFREQ_TABLE_UNSORTED)) + return cpufreq_table_index_unsorted(policy, target_freq, + relation); + + switch (relation) { + case CPUFREQ_RELATION_L: + return cpufreq_table_find_index_l(policy, target_freq); + case CPUFREQ_RELATION_H: + return cpufreq_table_find_index_h(policy, target_freq); + case CPUFREQ_RELATION_C: + return cpufreq_table_find_index_c(policy, target_freq); + default: + pr_err("%s: Invalid relation: %d\n", __func__, relation); + return -EINVAL; + } +} #else static inline int cpufreq_boost_trigger_state(int state) {