From 3cf2723432dd27402a4a4941ad2d04eae5dd639c Mon Sep 17 00:00:00 2001 From: David Brownell Date: Sun, 6 Apr 2008 23:32:55 -0700 Subject: [PATCH] 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 --- drivers/usb/gadget/at91_udc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/usb/gadget/at91_udc.c b/drivers/usb/gadget/at91_udc.c index fd15ced899d..5d352c900d2 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); -- 2.41.1