How to check GPU clock for 8660/8260 in Android

In Android platform, from 8x60, we support command line clock method through ADB and debugfs.
User can check current GPU clock using ADB following below direction.

1.     Mount the debug FS: adb shell "mount -t debugfs none /sys/kernel/debug"
2.     Check clock speeds (for 8660):
    a.     2D core #1: adb shell "cat /sys/kernel/debug/clk/gfx2d0_clk/measure"
    b.     2D core #2: adb shell "cat /sys/kernel/debug/clk/gfx2d1_clk/measure" (This is only for Adreno220)
    c.     3D core: adb shell "cat /sys/kernel/debug/clk/gfx3d_clk/measure"
3.     Write clock speeds (for 8660):
    a.     2D core #1: adb shell "echo <clock speed in Hz unit> /sys/kernel/debug/clk/gfx2d0_clk/rate"
    b.     2D core #2: adb shell "echo <clock speed in Hz unit> /sys/kernel/debug/clk/gfx2d1_clk/rate" (This is only for Adreno220)
    c.     3D core: adb shell "echo <clock speed in Hz unit> /sys/kernel/debug/clk/gfx3d_clk/rate"