DM8168 EVM uboot启动参数

setenv bootargs 'console=ttyO2,115200n8 rootwait root=/dev/mmcblk0p2 rw mem=364M@0x80000000 mem=320M@0x9FC00000 vmalloc=500M  notifyk.vpssm3_sva=0xBF900000 ip=off noinitrd'

上面这个是我在ezsdk开发包中看到的sd卡启动模式参数，请问上面的vmalloc=500M表示的什么意思？用来干嘛？

另外我在很多资料中看到说bootarg参数需要设置vram参数，例如vram=20M ，请问这个参数在evm开发上需要设置吗？ 这个的作用是什么？

Louis：

关于vmalloc，可以参考：http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/717/t/204654.aspx

“Syslink/IPC allows creation of SharedRegions at config time. Config time means the information about the shared region is embedded in the firmware executable. When the firmware is loaded , the syslink HOST (cortex A8) side will map the SharedRegion into the kernel and user space on A8 . The bulk of the vmalloc requirement comes from the shared region size since the shared region is mapped into kernel space. Addition vmalloc space is used by the syslink when loading the firmware where each initialized section in the firmware results in a vmalloc. This will amount to a couple of MB but the bulk is due to shared region. SharedRegion is the shared memory heap from which all cores allocate frame buffers in OMX”

Louis：

回复 Louis:

关于bootargs中的Vram，值得是预留给Fbdev驱动的总的framebuffer，比如你在bootagrs中设置vram=50M。详细用法及说明可以参考VPSS Video Driver User Guide。