On 12/06/12 08:58, Vipin Kumar wrote:
On 12/6/2012 12:17 PM, Igor Grinberg wrote:
On 12/06/12 08:30, Vipin Kumar wrote:
Few pen drives take longer than usual for enumeration. The u-boot unlike linux does not depend on interrupts and works in polling and timeout mode.
This patch increases this timeout to increase the set of usb sticks that can be enumerated by u-boot
Signed-off-by: Vipin Kumarvipin.kumar@st.com
common/usb_hub.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-)
diff --git a/common/usb_hub.c b/common/usb_hub.c index e4a1201..24de9b7 100644 --- a/common/usb_hub.c +++ b/common/usb_hub.c @@ -393,17 +393,34 @@ static int usb_hub_configure(struct usb_device *dev) "" : "no "); usb_hub_power_on(hub);
- mdelay(1500);
a 1.5 seconds? This looks like a huge overkill... Even for broken usb sticks...
Yes, but we are not talking about performance in u-boot. And since we are working in a polling mode, we only have 1 chance to detect the pen-drive
Of course we _do care_ about performance and 1.5 seconds is huge and not justified impact. Where is this value come from? Any real justification? Or just: lets make it huge... Also, as I understand from your commit message, this is needed only for broken pens... Why should all others suffer?
If this is really needed, I think you can do better then this. For example instead of waiting 1.5 seconds no meter what each time, make it a busy/wait loop (like you do below) and expire after a timeout.
for (i = 0; i< dev->maxchild; i++) { ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1); unsigned short portstatus, portchange;int ret;ulong start = get_timer(0);do {ret = usb_get_port_status(dev, i + 1, portsts);if (ret< 0) {USB_HUB_PRINTF("get_port_status failed\n");break;}portstatus = le16_to_cpu(portsts->wPortStatus);portchange = le16_to_cpu(portsts->wPortChange);if ((portchange& USB_PORT_STAT_C_CONNECTION)&&(portstatus& USB_PORT_STAT_CONNECTION))break;
if (usb_get_port_status(dev, i + 1, portsts)< 0) {USB_HUB_PRINTF("get_port_status failed\n");
mdelay(100);} while (get_timer(start)< CONFIG_SYS_HZ * 10);if (ret< 0) continue;
}portstatus = le16_to_cpu(portsts->wPortStatus);portchange = le16_to_cpu(portsts->wPortChange); USB_HUB_PRINTF("Port %d Status %X Change %X\n", i + 1, portstatus, portchange);