Re: [PATCH 0/3] ARM: dts: bcm2711-rpi-cm4-io: Enable xHCI host

[Phil Elwell <phil@raspberrypi.com>]

On Mon, 27 Nov 2023 at 11:08, Stefan Wahren <wahrenst@gmx.net> wrote:
>
> Hi Justin,
>
> [add Phil]
>
> Am 27.11.23 um 07:02 schrieb Justin Chen:
> >
> >
> > On 11/25/23 6:56 PM, Stefan Wahren wrote:
> >> In contrast to the Raspberry Pi 4, the Compute Module 4 or the IO board
> >> does not have a VL805 USB 3.0 host controller, which is connected via
> >> PCIe. Instead, the BCM2711 on the Compute Module provides the built-in
> >> xHCI.
> >>
> >
> > Does this work? I maintain this built-in xHCI controller internally. I
> > wasn't aware the Compute Module uses this block.
> i successful tested this with a CM4 (arm 32 bit,
> multi_v7_lpae_defconfig) with eMMC. Before this series the USB devices
> (mouse, keyboard) connected to the host interface didn't work. After
> comparing vendor DTS with mainline i noticed the missing xHCI block [1].
> Unfortunately i wasn't able to get further information from the public
> datasheets. I don't know if the VideoCore does some magic tricks on the
> xHCI or i missed some downstream xHCI changes.
>
> > This block is held in reset and needs a bit toggled to get things
> > going. Florian, just to confirm, this is our "brcm,xhci-brcm-v2" block
> > correct?
> >
> > Justin
>
> [1]  -
> https://github.com/raspberrypi/linux/blob/rpi-6.1.y/arch/arm/boot/dts/bcm2711-rpi-ds.dtsi#L119

What's the question here? Does the XHCI block present in the
raspberrypi/linux dtsi file really exist? Yes it does.

Phil