[U-Boot] [PATCH] smsc95xx: Use zero length packets when RX fifo is empty
Using NAKs on empty RX fifo for bulk in transfers is the right choice for a interrupt driven model, but U-Boot uses polling and expects an immediate answer if there is no incoming packet. Using ZLP Bulk In Response (BIR) mode avoids unexpected timeouts in the host controller driver.
As ZLP mode is reset default, there is no need to set it.
Signed-off-by: Stefan Brüns stefan.bruens@rwth-aachen.de --- The current setting results in timeouts in the dwc2 hc driver, if an expected network response is lost. This is often hidden by incoming broadcast packets, as these trigger the completion of the bulk in transfer as well.
drivers/usb/eth/smsc95xx.c | 16 ---------------- 1 file changed, 16 deletions(-)
diff --git a/drivers/usb/eth/smsc95xx.c b/drivers/usb/eth/smsc95xx.c index 6e80184..ae8bc18 100644 --- a/drivers/usb/eth/smsc95xx.c +++ b/drivers/usb/eth/smsc95xx.c @@ -531,22 +531,6 @@ static int smsc95xx_init_common(struct usb_device *udev, struct ueth_data *dev, if (ret < 0) return ret;
- ret = smsc95xx_read_reg(udev, HW_CFG, &read_buf); - if (ret < 0) - return ret; - debug("Read Value from HW_CFG : 0x%08x\n", read_buf); - - read_buf |= HW_CFG_BIR_; - ret = smsc95xx_write_reg(udev, HW_CFG, read_buf); - if (ret < 0) - return ret; - - ret = smsc95xx_read_reg(udev, HW_CFG, &read_buf); - if (ret < 0) - return ret; - debug("Read Value from HW_CFG after writing " - "HW_CFG_BIR_: 0x%08x\n", read_buf); - #ifdef TURBO_MODE if (dev->pusb_dev->speed == USB_SPEED_HIGH) { burst_cap = DEFAULT_HS_BURST_CAP_SIZE / HS_USB_PKT_SIZE;
On Mon, Sep 7, 2015 at 10:12 PM, Stefan Brüns stefan.bruens@rwth-aachen.de wrote:
Using NAKs on empty RX fifo for bulk in transfers is the right choice for a interrupt driven model, but U-Boot uses polling and expects an immediate answer if there is no incoming packet. Using ZLP Bulk In Response (BIR) mode avoids unexpected timeouts in the host controller driver.
As ZLP mode is reset default, there is no need to set it.
Signed-off-by: Stefan Brüns stefan.bruens@rwth-aachen.de
LGTM.
Acked-by: Joe Hershberger joe.hershberger@ni.com
On Tuesday 08 September 2015 08:56:12 Joe Hershberger wrote:
On Mon, Sep 7, 2015 at 10:12 PM, Stefan Brüns
stefan.bruens@rwth-aachen.de wrote:
Using NAKs on empty RX fifo for bulk in transfers is the right choice for a interrupt driven model, but U-Boot uses polling and expects an immediate answer if there is no incoming packet. Using ZLP Bulk In Response (BIR) mode avoids unexpected timeouts in the host controller driver.
As ZLP mode is reset default, there is no need to set it.
Signed-off-by: Stefan Brüns stefan.bruens@rwth-aachen.de
LGTM.
Acked-by: Joe Hershberger joe.hershberger@ni.com
Anything I need to do to get this patch and the other ones I sent recently included into U-boot?
All pending patches were ACKed.
Kind regards,
Stefan
Hi Stefan,
On Sun, Sep 13, 2015 at 11:45 AM, Stefan Bruens stefan.bruens@rwth-aachen.de wrote:
On Tuesday 08 September 2015 08:56:12 Joe Hershberger wrote:
On Mon, Sep 7, 2015 at 10:12 PM, Stefan Brüns
stefan.bruens@rwth-aachen.de wrote:
Using NAKs on empty RX fifo for bulk in transfers is the right choice for a interrupt driven model, but U-Boot uses polling and expects an immediate answer if there is no incoming packet. Using ZLP Bulk In Response (BIR) mode avoids unexpected timeouts in the host controller driver.
As ZLP mode is reset default, there is no need to set it.
Signed-off-by: Stefan Brüns stefan.bruens@rwth-aachen.de
LGTM.
Acked-by: Joe Hershberger joe.hershberger@ni.com
Anything I need to do to get this patch and the other ones I sent recently included into U-boot?
All pending patches were ACKed.
Any that are bugs that affect existing devices will be considered. All enhancements will wait until next time the merge window opens.
See http://www.denx.de/wiki/U-Boot/ReleaseCycle
Cheers, -Joe
On Mon, Sep 7, 2015 at 10:12 PM, Stefan Brüns stefan.bruens@rwth-aachen.de wrote:
Using NAKs on empty RX fifo for bulk in transfers is the right choice for a interrupt driven model, but U-Boot uses polling and expects an immediate answer if there is no incoming packet. Using ZLP Bulk In Response (BIR) mode avoids unexpected timeouts in the host controller driver.
As ZLP mode is reset default, there is no need to set it.
Signed-off-by: Stefan Brüns stefan.bruens@rwth-aachen.de
Applied to u-boot-net/master, thanks! -Joe
participants (3)
-
Joe Hershberger -
Stefan Bruens -
Stefan Brüns