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

Lukasz Majewski
2014-01-31T12:16:26Z

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

Change-Id: Id7f60b96cc5804038a2b4050fb6ddc96414cab5d
Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Cc: Marek Vasut <marex@denx.de>
---
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 eaa3a20..274b68c 100644
--- a/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c
+++ b/drivers/usb/gadget/s3c_udc_otg_xfer_dma.c
@@ -101,18 +101,17 @@ 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