Clean up searching code for best frequency and add some safety checks.
diff -ru linux-original/arch/i386/kernel/cpu/cpufreq/longhaul.c linux/arch/i386/kernel/cpu/cpufreq/longhaul.c
--- linux-original/arch/i386/kernel/cpu/cpufreq/longhaul.c 2002-12-25 17:45:52.000000000 +0100
+++ linux/arch/i386/kernel/cpu/cpufreq/longhaul.c 2002-12-27 10:49:52.000000000 +0100
@@ -313,6 +313,10 @@
if ((!can_scale_fsb) && (newfsb != current_fsb))
return;
+ if (((clock_ratio[clock_ratio_index] * newfsb * 100) > highest_speed) ||
+ ((clock_ratio[clock_ratio_index] * newfsb * 100) < lowest_speed))
+ return;
+
freqs.old = longhaul_get_cpu_mult() * longhaul_get_cpu_fsb() * 100;
freqs.new = clock_ratio[clock_ratio_index] * newfsb * 100;
freqs.cpu = 0; /* longhaul.c is UP only driver */
@@ -582,18 +586,68 @@
policy->max = newmax;
+ cpufreq_verify_within_limits(policy, lowest_speed, highest_speed);
+
+ return 0;
+}
+
+
+static int longhaul_get_best_freq_for_fsb(struct cpufreq_policy *policy,
+ unsigned int min_mult,
+ unsigned int max_mult,
+ unsigned int fsb,
+ unsigned int *new_mult)
+{
+ unsigned int optimal = 0;
+ unsigned int found_optimal = 0;
+ unsigned int i;
+
+ switch(policy->policy) {
+ case CPUFREQ_POLICY_POWERSAVE:
+ optimal = max_mult;
+ break;
+ case CPUFREQ_POLICY_PERFORMANCE:
+ optimal = min_mult;
+ }
+
+ for(i=0; i<numscales; i++) {
+ unsigned int freq = fsb * clock_ratio[i] * 100;
+ if ((freq > policy->max) ||
+ (freq < policy->min))
+ continue;
+ switch(policy->policy) {
+ case CPUFREQ_POLICY_POWERSAVE:
+ if (clock_ratio[i] < clock_ratio[optimal]) {
+ found_optimal = 1;
+ optimal = i;
+ }
+ break;
+ case CPUFREQ_POLICY_PERFORMANCE:
+ if (clock_ratio[i] > clock_ratio[optimal]) {
+ found_optimal = 1;
+ optimal = i;
+ }
+ break;
+ }
+ }
+
+ if (found_optimal) {
+ *new_mult = optimal;
+ return 1;
+ }
return 0;
}
static int longhaul_setpolicy (struct cpufreq_policy *policy)
{
- unsigned int number_states = 0;
unsigned int i;
unsigned int fsb_index = 0;
unsigned int new_fsb = 0;
unsigned int new_clock_ratio = 0;
- unsigned int best_freq = -1;
+ unsigned int min_mult = 0;
+ unsigned int max_mult = 0;
+
if (!longhaul_driver)
return -EINVAL;
@@ -603,103 +657,36 @@
else
fsb_search_table = power_fsb_table;
+ for(i=0;i<numscales;i++) {
+ if (clock_ratio[max_mult] < clock_ratio[i])
+ max_mult = i;
+ else if (clock_ratio[min_mult] > clock_ratio[i])
+ min_mult = i;
+ }
+
if (can_scale_fsb==1) {
- for (fsb_index=0; fsb_search_table[fsb_index]!=-1; fsb_index++)
+ unsigned int found = 0;
+ for (fsb_index=0; fsb_search_table[fsb_index]!=-1; fsb_index++)
{
- unsigned int tmpcount = longhaul_statecount_fsb(policy, fsb_search_table[fsb_index]);
- if (tmpcount == 1)
+ if (longhaul_get_best_freq_for_fsb(policy,
+ min_mult, max_mult,
+ fsb_search_table[fsb_index],
+ &new_clock_ratio)) {
new_fsb = fsb_search_table[fsb_index];
- number_states += tmpcount;
+ break;
+ }
}
+ if (!found)
+ return -EINVAL;
} else {
- number_states = longhaul_statecount_fsb(policy, current_fsb);
new_fsb = current_fsb;
- }
-
- if (!number_states)
- return -EINVAL;
- else if (number_states == 1) {
- for(i=0; i<numscales; i++) {
- if ((clock_ratio[i] != -1) &&
- ((clock_ratio[i] * new_fsb * 100) <= policy->max) &&
- ((clock_ratio[i] * new_fsb * 100) >= policy->min))
- new_clock_ratio = i;
- }
- longhaul_setstate(new_clock_ratio, new_fsb);
- }
-
- switch (policy->policy) {
- case CPUFREQ_POLICY_POWERSAVE:
- best_freq = -1;
- if (can_scale_fsb==1) {
- for (fsb_index=0; fsb_search_table[fsb_index]!=-1; fsb_index++)
- {
- for(i=0; i<numscales; i++) {
- unsigned int tmpfreq = fsb_search_table[fsb_index] * clock_ratio[i] * 100;
- if (clock_ratio[i] == -1)
- continue;
-
- if ((tmpfreq >= policy->min) &&
- (tmpfreq <= policy->max) &&
- (tmpfreq < best_freq)) {
- new_clock_ratio = i;
- new_fsb = fsb_search_table[fsb_index];
- }
- }
- }
- } else {
- for(i=0; i<numscales; i++) {
- unsigned int tmpfreq = current_fsb * clock_ratio[i] * 100;
- if (clock_ratio[i] == -1)
- continue;
-
- if ((tmpfreq >= policy->min) &&
- (tmpfreq <= policy->max) &&
- (tmpfreq < best_freq)) {
- new_clock_ratio = i;
- new_fsb = current_fsb;
- }
- }
- }
- break;
- case CPUFREQ_POLICY_PERFORMANCE:
- best_freq = 0;
- if (can_scale_fsb==1) {
- for (fsb_index=0; fsb_search_table[fsb_index]!=-1; fsb_index++)
- {
- for(i=0; i<numscales; i++) {
- unsigned int tmpfreq = fsb_search_table[fsb_index] * clock_ratio[i] * 100;
- if (clock_ratio[i] == -1)
- continue;
-
- if ((tmpfreq >= policy->min) &&
- (tmpfreq <= policy->max) &&
- (tmpfreq > best_freq)) {
- new_clock_ratio = i;
- new_fsb = fsb_search_table[fsb_index];
- }
- }
- }
- } else {
- for(i=0; i<numscales; i++) {
- unsigned int tmpfreq = current_fsb * clock_ratio[i] * 100;
- if (clock_ratio[i] == -1)
- continue;
-
- if ((tmpfreq >= policy->min) &&
- (tmpfreq <= policy->max) &&
- (tmpfreq > best_freq)) {
- new_clock_ratio = i;
- new_fsb = current_fsb;
- }
- }
- }
- break;
- default:
- return -EINVAL;
+ if (!longhaul_get_best_freq_for_fsb(policy, min_mult,
+ max_mult, new_fsb, &new_clock_ratio))
+ return -EINVAL;
}
longhaul_setstate(new_clock_ratio, new_fsb);
+
return 0;
}
-
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This archive was generated by hypermail 2b29 : Tue Dec 31 2002 - 22:00:13 EST