Re: [PATCH v5 6/7] PCI: dwc: al: Add support for DW based driver type

From: "Chocron, Jonathan" <jonnyc@amazon.com>
To: "helgaas@kernel.org" <helgaas@kernel.org>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"robh+dt@kernel.org" <robh+dt@kernel.org>,
	"jingoohan1@gmail.com" <jingoohan1@gmail.com>,
	"Woodhouse, David" <dwmw@amazon.co.uk>,
	"Hanoch, Uri" <hanochu@amazon.com>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"lorenzo.pieralisi@arm.com" <lorenzo.pieralisi@arm.com>,
	"gustavo.pimentel@synopsys.com" <gustavo.pimentel@synopsys.com>,
	"Wasserstrom, Barak" <barakw@amazon.com>,
	"Saidi, Ali" <alisaidi@amazon.com>,
	"mark.rutland@arm.com" <mark.rutland@arm.com>,
	"andrew.murray@arm.com" <andrew.murray@arm.com>,
	"Hawa, Hanna" <hhhawa@amazon.com>,
	"Shenhar, Talel" <talel@amazon.com>,
	"Krupnik, Ronen" <ronenk@amazon.com>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	"benh@kernel.crashing.org" <benh@kernel.crashing.org>,
	"Chocron, Jonathan" <jonnyc@amazon.com>
Subject: Re: [PATCH v5 6/7] PCI: dwc: al: Add support for DW based driver type
Date: Thu, 12 Sep 2019 12:55:04 +0000	[thread overview]
Message-ID: <a8903f853cd37c23d3325e69b25e9e86942f5322.camel@amazon.com> (raw)
In-Reply-To: <20190907165557.GO103977@google.com>

On Sat, 2019-09-07 at 11:55 -0500, Bjorn Helgaas wrote:
> s/Add support for DW based driver type/Add Amazon Annapurna Labs PCIe
> controller driver/
> 
Ack.

> On Thu, Sep 05, 2019 at 05:01:43PM +0300, Jonathan Chocron wrote:
> > This driver is DT based and utilizes the DesignWare APIs.
> > 
> > It allows using a smaller ECAM range for a larger bus range -
> > usually an entire bus uses 1MB of address space, but the driver
> > can use it for a larger number of buses. This is achieved by using
> > a HW
> > mechanism which allows changing the BUS part of the "final"
> > outgoing
> > config transaction. There are 2 HW regs, one which is basically a
> > bitmask determining which bits to take from the AXI transaction
> > itself
> > and another which holds the complementary part programmed by the
> > driver.
> > 
> > All link initializations are handled by the boot FW.
> > 
> > Signed-off-by: Jonathan Chocron <jonnyc@amazon.com>
> > Reviewed-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
> > Reviewed-by: Andrew Murray <andrew.murray@arm.com>
> > ---
> >  drivers/pci/controller/dwc/Kconfig   |  12 +
> >  drivers/pci/controller/dwc/pcie-al.c | 365
> > +++++++++++++++++++++++++++
> >  2 files changed, 377 insertions(+)
> > 
> > diff --git a/drivers/pci/controller/dwc/Kconfig
> > b/drivers/pci/controller/dwc/Kconfig
> > index 4fada2e93285..0ba988b5b5bc 100644
> > --- a/drivers/pci/controller/dwc/Kconfig
> > +++ b/drivers/pci/controller/dwc/Kconfig
> > @@ -256,4 +256,16 @@ config PCIE_UNIPHIER
> >  	  Say Y here if you want PCIe controller support on UniPhier
> > SoCs.
> >  	  This driver supports LD20 and PXs3 SoCs.
> >  
> > +config PCIE_AL
> > +	bool "Amazon Annapurna Labs PCIe controller"
> > +	depends on OF && (ARM64 || COMPILE_TEST)
> > +	depends on PCI_MSI_IRQ_DOMAIN
> > +	select PCIE_DW_HOST
> > +	help
> > +	  Say Y here to enable support of the Amazon's Annapurna Labs
> > PCIe
> > +	  controller IP on Amazon SoCs. The PCIe controller uses the
> > DesignWare
> > +	  core plus Annapurna Labs proprietary hardware wrappers. This
> > is
> > +	  required only for DT-based platforms. ACPI platforms with the
> > +	  Annapurna Labs PCIe controller don't need to enable this.
> 
> Interesting.  How do you deal with the funky ECAM space on ACPI
> platforms?  Oh, never mind, I see, it's the pcie-al.c ECAM ops quirk
> that's already in the tree.
> 
> Bjorn