Add UniPhier platform specific glue layer to support USB3 Host mode
on Synopsys DWC3 IP.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Marek Vasut <marex@denx.de>

Update the codes to conform with xHCI spec chapter 6.2.3.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

Per xHCI spec, 'Error Count' should be set to 0 for isoch endpoints.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

The 'Max Burst Size' indicates to the xHC the maximum number of
consecutive USB transactions that should be executed per scheduling
opportunity. This is a “zero-based” value, where 0 to 15 represents
burst sizes of 1 to 16, but at present this is always set to zero.
Let's program the required value according to real needs.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

USB endpoint reports the period between consecutive requests to send
or receive data as bInverval in its endpoint descriptor. So far this
is ignored by xHCI driver and the 'Interval' field in xHC's endpoint
context is always programmed to zero which means 1ms for low speed
or full speed , or 125us for high speed or super speed. We should
honor the interval by getting it from endpoint descriptor.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

In xhci_check_maxpacket(), the control endpoint 0 max packet size
is wrongly taken from the interface's endpoint descriptor. However
the default endpoint 0 does not come with an endpoint descriptor
hence is not included in the interface structure. Change to use
epmaxpacketin[0] instead.

The other bug in this routine is that when setting max packet size
to the xHC endpoint 0 context, it does not clear its previous value
at all before programming a new one.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

xHCI uses normal TRBs for both bulk and interrupt. This adds the
missing interrupt transfer support to xHCI so that devices like
USB keyboard that uses interrupt transfer can work.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

At present xHCI driver assumes LS/FS devices are attached directly
to a HS hub. If they are connected to a LS/FS hub, the driver will
fail to perform the USB enumeration process on such devices.

This is fixed by looking from the device itself all the way up to
the HS hub where the TT that serves the device is located.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

With the root hub unbinding in usb_stop(), there is no need to do
a Sandbox-specific reset operation. usb_emul_reset() is no longer
used anywhere, drop it.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>