From: David Brownell Date: Mon, 7 Apr 2008 06:32:55 +0000 (-0700) Subject: USB: at91_udc can prefetch data X-Git-Tag: accepted/tizen/common/20141203.182822~23373^2~32 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3cf2723432dd27402a4a4941ad2d04eae5dd639c;p=platform%2Fkernel%2Flinux-arm64.git 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/gadget/at91_udc.c b/drivers/usb/gadget/at91_udc.c index fd15ced..5d352c9 100644 --- a/drivers/usb/gadget/at91_udc.c +++ b/drivers/usb/gadget/at91_udc.c @@ -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);