Hi Nate,
On Tue, Jul 30, 2013 at 6:33 PM, Stoddard, Nate (GE Healthcare)
<[email protected]> wrote:
> So you would expect a temporary CPU increase when a device is connected or
> reset since the scheduler will need to set up when the packets will be
> transferred. Once this is complete, the CPU should return to a lower amount
> as
The reset function at drivers/usb/chipidea/core.c has the following:
int hw_device_reset(struct ci_hdrc *ci, u32 mode)
{
/* should flush & stop before reset */
hw_write(ci, OP_ENDPTFLUSH, ~0, ~0);
hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
hw_write(ci, OP_USBCMD, USBCMD_RST, USBCMD_RST);
while (hw_read(ci, OP_USBCMD, USBCMD_RST))
udelay(10); /* not RTOS friendly */
Maybe this udelay is impacting your performance?
It seems that this should be rewritten to avoid the busy loop.
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