powernow-k6: correctly initialize default parameters

[pandora-kernel.git] / drivers / cpufreq / powernow-k6.c

diff --git a/drivers/cpufreq/powernow-k6.c b/drivers/cpufreq/powernow-k6.c
index 8ee8568..ec6898e 100644 (file)
--- a/drivers/cpufreq/powernow-k6.c
+++ b/drivers/cpufreq/powernow-k6.c
@@ -25,6 +25,14 @@
 static unsigned int                     busfreq;   /* FSB, in 10 kHz */
 static unsigned int                     max_multiplier;
 
+static unsigned int                    param_busfreq = 0;
+static unsigned int                    param_max_multiplier = 0;
+
+module_param_named(max_multiplier, param_max_multiplier, uint, S_IRUGO);
+MODULE_PARM_DESC(max_multiplier, "Maximum multiplier (allowed values: 20 30 35 40 45 50 55 60)");
+
+module_param_named(bus_frequency, param_busfreq, uint, S_IRUGO);
+MODULE_PARM_DESC(bus_frequency, "Bus frequency in kHz");
 
 /* Clock ratio multiplied by 10 - see table 27 in AMD#23446 */
 static struct cpufreq_frequency_table clock_ratio[] = {
@@ -39,6 +47,27 @@ static struct cpufreq_frequency_table clock_ratio[] = {
        {0, CPUFREQ_TABLE_END}
 };
 
+static const struct {
+       unsigned freq;
+       unsigned mult;
+} usual_frequency_table[] = {
+       { 400000, 40 }, // 100   * 4
+       { 450000, 45 }, // 100   * 4.5
+       { 475000, 50 }, //  95   * 5
+       { 500000, 50 }, // 100   * 5
+       { 506250, 45 }, // 112.5 * 4.5
+       { 533500, 55 }, //  97   * 5.5
+       { 550000, 55 }, // 100   * 5.5
+       { 562500, 50 }, // 112.5 * 5
+       { 570000, 60 }, //  95   * 6
+       { 600000, 60 }, // 100   * 6
+       { 618750, 55 }, // 112.5 * 5.5
+       { 660000, 55 }, // 120   * 5.5
+       { 675000, 60 }, // 112.5 * 6
+       { 720000, 60 }, // 120   * 6
+};
+
+#define FREQ_RANGE             3000
 
 /**
  * powernow_k6_get_cpu_multiplier - returns the current FSB multiplier
@@ -162,18 +191,57 @@ static int powernow_k6_target(struct cpufreq_policy *policy,
        return 0;
 }
 
-
 static int powernow_k6_cpu_init(struct cpufreq_policy *policy)
 {
        unsigned int i, f;
        int result;
+       unsigned khz;
 
        if (policy->cpu != 0)
                return -ENODEV;
 
-       /* get frequencies */
-       max_multiplier = powernow_k6_get_cpu_multiplier();
-       busfreq = cpu_khz / max_multiplier;
+       max_multiplier = 0;
+       khz = cpu_khz;
+       for (i = 0; i < ARRAY_SIZE(usual_frequency_table); i++) {
+               if (khz >= usual_frequency_table[i].freq - FREQ_RANGE &&
+                   khz <= usual_frequency_table[i].freq + FREQ_RANGE) {
+                       khz = usual_frequency_table[i].freq;
+                       max_multiplier = usual_frequency_table[i].mult;
+                       break;
+               }
+       }
+       if (param_max_multiplier) {
+               for (i = 0; (clock_ratio[i].frequency != CPUFREQ_TABLE_END); i++) {
+                       if (clock_ratio[i].index == param_max_multiplier) {
+                               max_multiplier = param_max_multiplier;
+                               goto have_max_multiplier;
+                       }
+               }
+               printk(KERN_ERR "powernow-k6: invalid max_multiplier parameter, valid parameters 20, 30, 35, 40, 45, 50, 55, 60\n");
+               return -EINVAL;
+       }
+
+       if (!max_multiplier) {
+               printk(KERN_WARNING "powernow-k6: unknown frequency %u, cannot determine current multiplier\n", khz);
+               printk(KERN_WARNING "powernow-k6: use module parameters max_multiplier and bus_frequency\n");
+               return -EOPNOTSUPP;
+       }
+
+have_max_multiplier:
+       param_max_multiplier = max_multiplier;
+
+       if (param_busfreq) {
+               if (param_busfreq >= 50000 && param_busfreq <= 150000) {
+                       busfreq = param_busfreq / 10;
+                       goto have_busfreq;
+               }
+               printk(KERN_ERR "powernow-k6: invalid bus_frequency parameter, allowed range 50000 - 150000 kHz\n");
+               return -EINVAL;
+       }
+
+       busfreq = khz / max_multiplier;
+have_busfreq:
+       param_busfreq = busfreq * 10;
 
        /* table init */
        for (i = 0; (clock_ratio[i].frequency != CPUFREQ_TABLE_END); i++) {