On 06/27/2013 03:45 AM, Jim Lin wrote: > TFTP booting is observed a little bit slow, especially when a USB > keyboard is installed. > The fix is to move polling to every second if we sense that other task > like TFTP boot is running. >
> diff --git a/common/usb_kbd.c b/common/usb_kbd.c > +#ifdef CONFIG_USBKB_TESTC_PERIOD > + /* > + * T is the time between two calls of usb_kbd_testc(). > + * If CONFIG_USBKB_TESTC_PERIOD ms < T < 1000 ms, > + * it implies other task like TFTP boot is running, > + * then we reduce polling to every second > + * to improve TFTP booting performance. > + */ > + if ((get_timer(kbd_testc_tms) >= > + (CONFIG_USBKB_TESTC_PERIOD * CONFIG_SYS_HZ / 1000)) && > + (get_timer(kbd_testc_tms) < CONFIG_SYS_HZ)) > + return 0; > + else > + kbd_testc_tms = get_timer(0); > +#endif I have a hard time understanding why the fact that "some other task is running" implies anything at all re: how often usb_kbd_testc() would be called. It's quite possible that "some other task" is extremely fine-grained, and calls usb_kbd_testc() every 0.1ms, and would be severely negatively affected by usb_kbd_testc() taking a long time to execute. Conversly, it's quite possible that "some other task" is quite granular, and calls usb_kbd_testc() a wide intervals, say every 200ms. So, I think this change keys of entirely the wrong thing. Shouldn't the TFTP process (or use of USB networking?) or other long-running tasks that do check for keyboard IO simply set some flag to indicate to usb_kbd_testc() that it should run at a reduced rate, or even just have those long-running processses call usb_kbd_testc() at a reduced rate themselves? _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
