USB: at91_udc can prefetch data

The at91sam9 chip are ARMv5 so they support preload instructions.
Use preloading to load the FIFO a bit faster.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
David Brownell 2008-04-06 23:32:55 -07:00 committed by Greg Kroah-Hartman
parent a89a2cd396
commit 3cf2723432

View file

@ -389,6 +389,7 @@ static int write_fifo(struct at91_ep *ep, struct at91_request *req)
u32 csr = __raw_readl(creg);
u8 __iomem *dreg = ep->creg + (AT91_UDP_FDR(0) - AT91_UDP_CSR(0));
unsigned total, count, is_last;
u8 *buf;
/*
* TODO: allow for writing two packets to the fifo ... that'll
@ -413,6 +414,8 @@ static int write_fifo(struct at91_ep *ep, struct at91_request *req)
return 0;
}
buf = req->req.buf + req->req.actual;
prefetch(buf);
total = req->req.length - req->req.actual;
if (ep->ep.maxpacket < total) {
count = ep->ep.maxpacket;
@ -435,7 +438,7 @@ static int write_fifo(struct at91_ep *ep, struct at91_request *req)
* recover when the actual bytecount matters (e.g. for USB Test
* and Measurement Class devices).
*/
__raw_writesb(dreg, req->req.buf + req->req.actual, count);
__raw_writesb(dreg, buf, count);
csr &= ~SET_FX;
csr |= CLR_FX | AT91_UDP_TXPKTRDY;
__raw_writel(csr, creg);