Re: [PATCH v5 0/9] Raspberry Pi 4 USB firmware initialization rework

From: Greg KH <gregkh@linuxfoundation.org>
To: Florian Fainelli <f.fainelli@gmail.com>
Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>,
	robh@kernel.org, wahrenst@gmx.net, p.zabel@pengutronix.de,
	andy.shevchenko@gmail.com, linux-usb@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-rpi-kernel@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	bcm-kernel-feedback-list@broadcom.com, tim.gover@raspberrypi.org,
	linux-pci@vger.kernel.org, helgaas@kernel.org,
	mathias.nyman@linux.intel.com, lorenzo.pieralisi@arm.com
Subject: Re: [PATCH v5 0/9] Raspberry Pi 4 USB firmware initialization rework
Date: Fri, 14 Aug 2020 08:11:05 +0200	[thread overview]
Message-ID: <20200814061105.GG1409566@kroah.com> (raw)
In-Reply-To: <01e4b87c-d287-fd72-9f9c-545539127a50@gmail.com>

On Thu, Aug 13, 2020 at 12:17:49PM -0700, Florian Fainelli wrote:
> 
> 
> On 8/13/2020 3:01 AM, Nicolas Saenz Julienne wrote:
> > Hi everyone.
> > 
> > On Mon, 2020-06-29 at 18:18 +0200, Nicolas Saenz Julienne wrote:
> > > On the Raspberry Pi 4, after a PCI reset, VL805's firmware may either be
> > > loaded directly from an EEPROM or, if not present, by the SoC's
> > > co-processor, VideoCore. This series reworks how we handle this.
> > > 
> > > The previous solution makes use of PCI quirks and exporting platform
> > > specific functions. Albeit functional it feels pretty shoehorned. This
> > > proposes an alternative way of handling the triggering of the xHCI chip
> > > initialization trough means of a reset controller.
> > > 
> > > The benefits are pretty evident: less platform churn in core xHCI code,
> > > and no explicit device dependency management in pcie-brcmstb.
> > > 
> > > Note that patch #1 depends on another series[1], that was just applied
> > > into the clk maintainer's tree.
> > > 
> > > The series is based on v5.8-rc3
> > > 
> > > v3: https://www.spinics.net/lists/arm-kernel/msg813612.html
> > > v2: https://lkml.org/lkml/2020/6/9/875
> > > v1: https://lore.kernel.org/linux-usb/20200608192701.18355-1-nsaenzjulienne@suse.de/T/#t
> > > 
> > > [1] https://lore.kernel.org/linux-clk/159304773261.62212.983376627029743900@swboyd.mtv.corp.google.com/T/#t
> > > 
> > > ---
> > 
> > We were waiting on a dependency to be merged upstream to get this. They are now
> > in, so could we move things forward?
> > 
> > I can take the device tree patches, I guess philipp can take the reset
> > controller code. But I'm not so sure who should be taking the PCI/USB
> > counterparts.
> 
> Should we route everything through the USB tree since that is where the
> changes that do require synchronization with other subsystems and DTS is
> needed the most?
> -- 
> Florian

That's fine with me, if everyone else is ok with it :)