On Tue, Mar 15, 2016 at 8:59 PM, Stefan Roese <s...@denx.de> wrote: > This patch changes the USB port scanning procedure and timeout > handling in the following ways: > > a) > The power-on delay in usb_hub_power_on() is now reduced to a value of > max(100ms, "hub->desc.bPwrOn2PwrGood * 2"). The code does not wait > using mdelay, instead usb_hub_power_on() will wait before querying > the device in the scanning loop later. The total timeout for this > hub, which is 1 second + "hub->desc.bPwrOn2PwrGood * 2" is calculated > and will be used in the following per-port scanning loop as the timeout > to detect active USB devices on this hub. > > b) > Don't delay the minimum delay (for power to stabilize) in > usb_hub_power_on(). Instead skip querying these devices in the scannig > loop until the delay time is reached. > > c) > The ports are now scanned in a quasi parallel way. The current code did > wait for each (unconnected) port to reach its timeout and only then > continue with the next port. This patch now changes this to scan all > ports of all USB hubs quasi simultaneously. For this, all ports are added > to a scanning list. This list is scanned until all ports are ready > by either a) reaching the connection timeout (calculated earlier), or > by b) detecting a USB device. This results in a faster USB scan time as > the recursive scanning of USB hubs connected to the hub that's currently > being scanned will start earlier. > > One small functional change to the original code is, that ports with > overcurrent detection will now get rescanned multiple times > (PORT_OVERCURRENT_MAX_SCAN_COUNT). > > Without this patch: > starting USB... > USB0: USB EHCI 1.00 > scanning bus 0 for devices... 9 USB Device(s) found > > time: 20.163 seconds > > With this patch: > starting USB... > USB0: USB EHCI 1.00 > scanning bus 0 for devices... 9 USB Device(s) found > > time: 1.822 seconds > > So ~18.3 seconds of USB scanning time reduction. > > Signed-off-by: Stefan Roese <s...@denx.de> > Acked-by: Hans de Goede <hdego...@redhat.com> > Tested-by: Stephen Warren <swar...@nvidia.com> > > --- > > Changes in v5: > - Removed superfluous debug output from usb_scan_port() > - Replaced usb_hub_power_on() with usb_set_port_feature() in case > of overcurrent detection. This is whats really needed here. > - Added a per-port overcurrent counter and stop re-scanning of > a device that exceeds the PORT_OVERCURRENT_MAX_SCAN_COUNT > - Moved list_del() to end of loop in usb_scan_port() > - Moved timeout / delay variables from USB dev to hub struct > as they are hub specific > - Moved state_get_skip_delays() to usb_hub_power_on() so that > the timeouts are not set there > > Changes in v4: > - Moved check for query_delay into usb_scan_port() as suggested by Hans > - Correct list handling (drop INIT_LIST_HEAD) > - Added some missing free() calls > - Changed connect_timeout calculation as suggested by Stephen > - Moved usb_scan_list to other globals to be cleaned up in a later patch > - Added timeout check for non-functional ports (usb_get_port_status > return error > - Reverted if logic in loop to remove an indentation level > - Moved debug() output > - Removed unnecessary if when already connected > - Added Hans's Acked-by > - Added Stephen's Tested-by > - Minor rewording / fixes of the commit text > > Changes in v3: > - Introduced scanning list containing all USB devices of one USB > controller that need to get scanned > - Don't delay in usb_hub_power_on(). Instead skip querying these devices > until the delay time is reached. > > Changes in v2: > - Remove static USB port configuration patch (for now) > > common/usb_hub.c | 317 > ++++++++++++++++++++++++++++++++++++++----------------- > include/usb.h | 4 + > 2 files changed, 227 insertions(+), 94 deletions(-) >
Tested-by: Bin Meng <bmeng...@gmail.com> _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot