Linux/66AK2G12: A15 cpu speed looks slow in Dhrystone ?

Hi,

This is just a side note; EVM TRM state IP address should be displayed on LCD, but I could not see any IP information when the linux kernel is booted on A15. Is this expected behavior ?

To get the IP address, you need to have the K2G EVM ethernet connected to a PC, which is configured as DHCP server. So, if you don't have the EVM ethernet connected, then YES, this is expected.

[qoute]In summary, the kernel looked running at 600Mhz, but BogoMIPS and Dhrystone show quite a small numbers. Is this expected behavior ?[/quote]

This does not seem to be a normal behavior of the board. Let me check the SDK sources and I will update.

Best Regards,
Yordan

Hello Yordan,

Thanks for your reply. Please note: in my case, i had connected the EVM to my local network via ethernet cable. Also, i had assigned an unique static IP address to EVM by issuing 'setenv ipaddr xx.xx.xx.xx' in u-boot stage.
After the kernel booted, I verified the specified ip address assigned to EVM via ifconfig command and accessed that ip address via browser (PC in the same network) to launch matrix UI. Yes, it actually worked, however, i didn't see the ip on LCD... I think this could happen in DHCP use case.

As for the performance issue, please let me know if you have any findings.

Best Regards,
NK

I'm now out of office and I can't confirm in detail, but i believe my 66AK2G02 EVM revision is D1.3. Just for your information.

Naoki Kawada said:

I'm now out of office and I can't confirm in detail, but i believe my 66AK2G02 EVM revision is D1.3. Just for your information.

I verified that this was correct for my environment.

So, did you find any problems at your side ?

Best Regards,
NK

Hi Rex,

Can you specify the exact file for makefile ? I saw ti-processor-sdk-linux-k2g-evm-04.03.00.05\example-applications\arm-benchmarks-1.3\dhrystone\Makefile, but I could not find the comments.

Also, please suggest for IP address issue (No IP address printed on LCD).

Best Regards,
NK

Please submit a separate thread for LCD IP issue.

Rex

Hi Rex

I checked the following script and added debug print (see echo "NK Debug: CPU Freq = $CPUFREQ")

ti-processor-sdk-linux-k2g-evm-04.03.00.05\example-applications\arm-benchmarks-1.3\scripts\runDhrystone

echo ""
echo ""
echo ""
echo "Dhrystone running ..."
echo ""
echo "Execution time 10 seconds or longer depending on your CPU clock speed"
if test -e /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq; then
CPUFREQ=`cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq`
else if test -e /proc/cpuinfo; then
        a=(`cat /proc/cpuinfo | grep Bogo | awk '{print $3}'`)
        b=`echo "($a+5)/10*10" | bc`
        let CPUFREQ=b*1000
     fi
fi
echo "NK Debug: CPU Freq = $CPUFREQ"
dhrystone 200000000 $CPUFREQ
echo ""

As a result, I got the log of "NK Debug: CPU Freq = 50000" when executed the dhrystone. 
Because of no entry for /sys/devices/system/cpu/cpu0/cpufreq, It seemed the script estimated the CPU freq from the BogoMIPS.

So in summary, the root cause looked the result of BogoMIPS number is far from the expected value.

Any comment ?

Best Regards,
NK

 

Hi, Rex

I`m not asking the implementation of dhrystone. I know it is open source, so I read the code by myself and understood the cpu freq had been passed as an argument of dhrystone. And I did grep the existing code and found the script i shared in the previous post was actually passed wrong number for cpu freq (It had been actually originated from BogoMIPS). I know BogoMIPS is not accurate, but it is too far from the actual cpu frequency. This can be problem for dhrystone benchmark. Or, from the different point of view, we should use /proc/cpuinfo rather than bogoMIPS, but there is no cpu freq entry. That may be another problem.

Anyway, i think we are in sync. Please ask your internal test team.

Best Regards,
NK

Hi Rex,

OK, thanks. I got the same number for DMIPS/Mhz (i.e, 3.6) with the performance guide on my setup.

The run script looks like this:

echo ""
echo ""
echo ""
echo "Dhrystone running ..."
echo ""
echo "Execution time 10 seconds or longer depending on your CPU clock speed"
if test -e /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq; then
CPUFREQ=`cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq`
else if test -e /proc/cpuinfo; then
        a=(`cat /proc/cpuinfo | grep Bogo | awk '{print $3}'`)
        b=`echo "($a+5)/10*10" | bc`
#        let CPUFREQ=b*1000
        let CPUFREQ=600*1000
		echo "Overriden CPU Freq (kHz): $CPUFREQ"
     fi
fi
dhrystone 200000000 $CPUFREQ
echo ""

The script is very confusing, so maybe, it is good to fix it in the future release of SDK to be more K2G specific. Thanks for your consideration.

Now I close the thread. Thanks for all your support.

Best Regards,
NK

Hi, Naoki,

Thanks for your suggestion on the script, but it will only apply to K2G02 device. Other devices without PM have different frequencies from K2G02's 600MHz. The script file from System Test covers certain targeted devices. For other devices, such as K2G, it manually fixes the frequencies to publish. What users should do is to follow Dhrystone user's guide in public domain. 

Rex

Naoki,

A side note on IP address not displaying on LCD. It seems that it is broken when migrating to ProcSDK 4.x. It was working in ProcSDK 3.x. I'll submit a bug to have it fixed.

Rex

Ok, i got it! Thanks for your notification.

Best Regards,
NK