implementing "suspend to ram" on cortex A8 based on linux 3.0.8
21cnbao at gmail.com
Tue Mar 13 14:34:18 UTC 2012
在 2012年3月10日 下午10:37，yang gqyang <hustgqyang at gmail.com> 写道：
> Thanks for your comment.
> Finally, i find out that i made a mistake. The uart(8250) have not been
> restore after resume, instead, it use the configuration got from boot. The
> uart have not been restored correctly, so that "ls" can not output result
> correctly resulting in it seems that the busybox can not work correctly.
> Now, i still have a question about the uart: why the "printk" can work
> correctly, but the "printf" not?
> Before this, i believe that the "printk" work correctly, then the uart
> work ok. but now, i need more reconsidaration about
> the relation between the "printk", "printf" and "uart".
> Can anyone give me some suggestion? Any comment is welcome, thanks a
printk use "struct console" driver, it doesn't depend on a device node
printf actaully depends on uart_driver and a /dev/ttySx device node,
stdout and stderr are redirected to /dev/ttySx
uart is just a hardware which can be a tty or kernel console output.
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