This is a patch by Benjamin Herrenschmidt, I just put it here because I had to collect it from two pieces:
http://lists.debian.org/debian-powerpc/2005/03/msg00554.html http://article.gmane.org/gmane.linux.debian.ports.powerpc/27133
--- linux-work.orig/arch/ppc/platforms/pmac_cpufreq.c 2005-03-13 18:23:11.000000000 +1100
+++ linux-work/arch/ppc/platforms/pmac_cpufreq.c 2005-03-14 13:32:36.000000000 +1100
@@ -464,20 +464,22 @@
u32 *reg;
struct cpufreq_driver *driver = &pmac_cpufreq_driver;
- /* OF only reports the high frequency */
- hi_freq = cur_freq;
- low_freq = cur_freq/2;
- driver->get = dfs_get_cpu_speed;
- cur_freq = driver->get(0);
-
+ /* Look for voltage GPIO */
volt_gpio_np = of_find_node_by_name(NULL, "cpu-vcore-select");
+ if (volt_gpio_np)
+ voltage_gpio = read_gpio(volt_gpio_np);
if (!volt_gpio_np){
printk(KERN_ERR "cpufreq: missing cpu-vcore-select gpio\n");
return 1;
}
- reg = (u32 *)get_property(volt_gpio_np, "reg", NULL);
- voltage_gpio = *reg;
+ /* OF only reports the high frequency */
+ hi_freq = cur_freq;
+ low_freq = cur_freq/2;
+
+ /* Read actual frequency from CPU */
+ driver->get = dfs_get_cpu_speed;
+ cur_freq = driver->get(0);
set_speed_proc = dfs_set_cpu_speed;
return 0;
@@ -492,7 +494,7 @@
* - iBook2 500/600 (PMU based, 400Mhz & 500/600Mhz)
* - iBook2 700 (CPU based, 400Mhz & 700Mhz, support low voltage)
* - Recent MacRISC3 laptops
- * - iBook G4s and PowerBook G4s with 7447A CPUs
+ * - All new machines with 7447A CPUs
*/
static int __init pmac_cpufreq_setup(void)
{
@@ -513,11 +515,10 @@
goto out;
cur_freq = (*value) / 1000;
- /* Check for 7447A based iBook G4 or PowerBook */
- if (machine_is_compatible("PowerBook6,5") ||
- machine_is_compatible("PowerBook6,4") ||
- machine_is_compatible("PowerBook5,5") ||
- machine_is_compatible("PowerBook5,4")) {
+ /* Check for 7447A based MacRISC3 */
+ if (machine_is_compatible("MacRISC3") &&
+ get_property(cpunode, "dynamic-power-step", NULL) &&
+ PVR_VER(mfspr(SPRN_PVR)) == 0x8003) {
pmac_cpufreq_init_7447A(cpunode);
/* Check for other MacRISC3 machines */
} else if (machine_is_compatible("PowerBook3,4") ||