Hi, If you are able to compile and flash your version of Kernel then you can write simple system calls such as GetCurrentFreq / SetCpuFreq internally using functions acpuclk_get_rate and acpuclk_set_rate respectively (both of these functions are defined in acpuclock.c file).
On Mar 29, 1:43 pm, Mike Chan <m...@android.com> wrote: > Does "adb su" work? If not, you will have to root your device. Search > google for how to root your android phone. > > -- Mike > > On Sat, Mar 27, 2010 at 12:28 PM, ecss utdallas > > <dianyuangua...@gmail.com> wrote: > > Thank you very much for your answer. But when I try to run "adb root", it > > shows the message "adbd cannot run as root in production builds". Can you > > tell me how to solve this problem? My phone is ADP2. Thank you very much~ > > > On Tue, Mar 23, 2010 at 3:22 PM, Mike Chan <m...@android.com> wrote: > > >> You need root access to change cpufreq values. I'm not sure if this is > >> available on the Google IO devices but try: > > >> adb root > > >> to switch into root mode, or adb su <foo> > > >> userspace is not compiled into the kernel for the ADP2, you will need > >> to either compile a custom kernel, or just pin the min/max speeds to > >> the speed you wish to set. > > >> -- Mike > > >> On Tue, Mar 23, 2010 at 1:16 PM, ecss utdallas <dianyuangua...@gmail.com> > >> wrote: > >> > Firstly, many thanks for your answer. That really helps a lot. I am > >> > using > >> > the ADP2 actually a google IO phone. When I did "adb shell cat > >> > /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governor". The > >> > result > >> > is : "ondemand, performance". It means that the sytem on my phone only > >> > supports ondemand and performance scaling governors. Also when I try to > >> > use > >> > "adb shell echo userspace > /sys/devices/.../scaling_governor", it > >> > always > >> > shows the problem that " Permission denied". Did you face similar > >> > problem > >> > when enable userspace governor? Would you please give me some advice on > >> > how > >> > to solve these problems? I will appreciate very very much for your help. > > >> > On Mon, Mar 22, 2010 at 1:42 PM, Mike Chan <m...@android.com> wrote: > > >> >> What phone did you buy? If you're talking about the Nexus One the > >> >> userspace governor is already compiled into the kernel. Otherwise > >> >> you'll probably have to recompile the kernel with the userspace > >> >> governor. > > >> >> We do DVFS using the ondemand governor currently. > > >> >> To enable userspace governor: > >> >> adb shell echo "userspace > > >> >> /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor" > > >> >> To set the speed: > > >> >> adb shell echo "xxx > > >> >> /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq" > > >> >> -- Mike > > >> >> On Sun, Mar 21, 2010 at 11:28 PM, xlshe <dianyuangua...@gmail.com> > >> >> wrote: > >> >> > I have bought the android develop phone 2. I want to do some research > >> >> > about > >> >> > power management on ADP2. But I wonder if ADP2 support Dynamic > >> >> > Voltage > >> >> > and > >> >> > Frequency Scaling(DVFS). That means whether we can change the CPU > >> >> > frequency > >> >> > dynamically on ADP2. Previously, someone told me that I can rebuild > >> >> > the > >> >> > android OS kernel and turn on the user space and then I can set the > >> >> > CPU > >> >> > frequency. I have tried to rebuild the kernel just as " > >> >> >http://source.android.com/documentation/building-for-dream"; said. But > >> >> > I > >> >> > still don't know how to turn on the user space when built the kernel > >> >> > and > >> >> > don't know how to set the CPU frequency on ADP2. Would you kindly > >> >> > give > >> >> > me > >> >> > some support on how to dynamically set the CPU frequency on ADP2? I > >> >> > will > >> >> > appreciate very very much for your support. > > >> >> > -- > >> >> > unsubscribe: android-kernel+unsubscr...@googlegroups.com > >> >> > website:http://groups.google.com/group/android-kernel > > >> >> > To unsubscribe from this group, send email to > >> >> > android-kernel+unsubscribegooglegroups.com or reply to this email > >> >> > with the > >> >> > words "REMOVE ME" as the subject. > > >> >> -- > >> >> unsubscribe: android-kernel+unsubscr...@googlegroups.com > >> >> website:http://groups.google.com/group/android-kernel > > >> >> To unsubscribe from this group, send email to > >> >> android-kernel+unsubscribegooglegroups.com or reply to this email with > >> >> the > >> >> words "REMOVE ME" as the subject. > > >> > -- > >> > unsubscribe: android-kernel+unsubscr...@googlegroups.com > >> > website:http://groups.google.com/group/android-kernel > > >> > To unsubscribe from this group, send email to > >> > android-kernel+unsubscribegooglegroups.com or reply to this email with > >> > the > >> > words "REMOVE ME" as the subject. > > >> -- > >> unsubscribe: android-kernel+unsubscr...@googlegroups.com > >> website:http://groups.google.com/group/android-kernel > > >> To unsubscribe from this group, send email to > >> android-kernel+unsubscribegooglegroups.com or reply to this email with the > >> words "REMOVE ME" as the subject. > > > -- > > unsubscribe: android-kernel+unsubscr...@googlegroups.com > > website:http://groups.google.com/group/android-kernel > > > To unsubscribe from this group, send email to > > android-kernel+unsubscribegooglegroups.com or reply to this email with the > > words "REMOVE ME" as the subject. -- unsubscribe: android-kernel+unsubscr...@googlegroups.com website: http://groups.google.com/group/android-kernel
