[U-Boot] [PATCH v2 3/6] usb:udc:samsung: Allow burst transfers for non EP0 endpints

Lukasz Majewski l.majewski at samsung.com
Wed Feb 5 10:10:43 CET 2014


This patch removed obscure restriction on the HW setting of DMA transfers.
Before this change each transaction sent up to 512 bytes (with packet count
equal to 1) for non EP0 transfer.

Now it is possible to setup DMA transaction up to DMA_BUFFER_SIZE.

Test condition
- test HW + measurement: Trats - Exynos4210 rev.1
- test HW Trats2 - Exynos4412 rev.1
400 MiB compressed rootfs image download with `thor 0 mmc 0`

Measurement:
Transmission speed: 20.74 MiB/s

Signed-off-by: Lukasz Majewski <l.majewski at samsung.com>
Cc: Marek Vasut <marex at denx.de>

---
Changes for v2:
- Remove Change-Id:
---
 drivers/usb/gadget/s3c_udc_otg_xfer_dma.c |    7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c b/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c
index cbc8734..7c7176b 100644
--- a/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c
+++ b/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c
@@ -97,18 +97,17 @@ static int setdma_rx(struct s3c_ep *ep, struct s3c_request *req)
 	u32 ep_num = ep_index(ep);
 
 	buf = req->req.buf + req->req.actual;
-
-	length = min(req->req.length - req->req.actual, (int)ep->ep.maxpacket);
+	length = min(req->req.length - req->req.actual,
+		     ep_num ? DMA_BUFFER_SIZE : ep->ep.maxpacket);
 
 	ep->len = length;
 	ep->dma_buf = buf;
 
-	if (length == 0)
+	if (ep_num == EP0_CON || length == 0)
 		pktcnt = 1;
 	else
 		pktcnt = (length - 1)/(ep->ep.maxpacket) + 1;
 
-	pktcnt = 1;
 	ctrl =  readl(&reg->out_endp[ep_num].doepctl);
 
 	writel(the_controller->dma_addr[ep_index(ep)+1],
-- 
1.7.10.4



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