Thank you for your suggestions. It's really very very helpfull. But the current problem I am facing is how to customize the kernel for my phone. I need to configure the CPU frequency of Android phone. However, the current kernel doesn't support "userspace" governor. So I need to rebuild the kernel and turn on the "userspace" or make it built as a module. At first I followed the instruction here " http://source.android.com/documentation/building-for-dream" to build kernel for Sapphire(my phone is ADP2). But I didn't find any approach like "make menuconfig" to customize the kernel as I need. Then I download the HTC magic kernel ource code from the HTC developer website http://developer.htc.com/ and try to rebuild that. But maybe, I need cross compiler or something else. I am still trying. I'm really confused about the various kinds of kernel source code and rebuild approaches from android website or HTC or other website. Actually, I just need one that can work. Do you have any suggestions about how to customize the kernel(Sapphire) for ADP2? Thank you very much!
On Tue, Mar 30, 2010 at 11:33 PM, Chintan <chinta...@gmail.com> wrote: > 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<android-kernel%2bunsubscr...@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<android-kernel%2bunsubscr...@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<android-kernel%2bunsubscr...@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<android-kernel%2bunsubscr...@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<android-kernel%2bunsubscr...@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<android-kernel%2bunsubscr...@googlegroups.com> > website: http://groups.google.com/group/android-kernel > -- unsubscribe: android-kernel+unsubscr...@googlegroups.com website: http://groups.google.com/group/android-kernel