How to find the physical address of framebuffer on android emulator (qemu)?

[QIAO]

I'm doing some experiments to linux kernel. I built goldfish-kernel and android-emulator as my platform.

Now I want to develop a test driver, which draw point on emulator's display. I was trying to use ioremap as follow:

void* fb_base;
fb_base = ioremap(FB_PHYSICAL_ADDR, SIZE);
writel(0x00ff0000, fb_base);    // draw a point on framebuffer

However, I can't find the physical address defined by android emulator, whichFB_PHYSICAL_ADDR should be.

I have searched the framebuffer driver of goldfish (kernel_src_root/drivers/video/goldfishfb.c) and android_emulator source code (android/external/qemu/) but in vain.

Please tell me where is the physical address/io memory defined in qemu, or any methods help me to obtain the physical address in qemu/android-emulator.

Thanks for any suggestions.