linux-kernel - Re: [PATCH 2/3] Docs: dt: Add PCI MSI map bindings

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150727091535.GA9169@leverpostej>
Date:	Mon, 27 Jul 2015 10:16:17 +0100
From:	Mark Rutland <mark.rutland@....com>
To:	"Chalamarla, Tirumalesh" <Tirumalesh.Chalamarla@...iumnetworks.com>
Cc:	"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"iommu@...ts.linux-foundation.org" <iommu@...ts.linux-foundation.org>,
	linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
	Will Deacon <Will.Deacon@....com>,
	Marc Zyngier <Marc.Zyngier@....com>,
	Robin Murphy <Robin.Murphy@....com>,
	Lorenzo Pieralisi <Lorenzo.Pieralisi@....com>,
	Arnd Bergmann <arnd@...db.de>,
	"treding@...dia.com" <treding@...dia.com>,
	"Daney, David" <David.Daney@...iumnetworks.com>,
	"majun258@...wei.com" <majun258@...wei.com>,
	"thunder.leizhen@...wei.com" <thunder.leizhen@...wei.com>,
	"laurent.pinchart@...asonboard.com" 
	<laurent.pinchart@...asonboard.com>
Subject: Re: [PATCH 2/3] Docs: dt: Add PCI MSI map bindings

> > +Example (5)
> > +===========
> > +
> > +/ {
> > +	#address-cells = <1>;
> > +	#size-cells = <1>;
> > +
> > +	msi_a: msi-controller@a {
> > +		reg = <0xa 0x1>;
> > +		compatible = "vendor,some-controller";
> > +		msi-controller;
> > +		#msi-cells = <1>;
> > +	};
> > +
> > +	msi_b: msi-controller@b {
> > +		reg = <0xb 0x1>;
> > +		compatible = "vendor,some-controller";
> > +		msi-controller;
> > +		#msi-cells = <1>;
> > +	};
> > +
> > +	msi_c: msi-controller@c {
> > +		reg = <0xc 0x1>;
> > +		compatible = "vendor,some-controller";
> > +		msi-controller;
> > +		#msi-cells = <1>;
> > +	};
> > +
> > +	pci: pci@c {
> > +		reg = <0xf 0x1>;
> > +		compatible = "vendor,pcie-root-complex";
> > +		device_type = "pci";
> > +
> > +		/*
> > +		 * The sideband data provided to MSI controller a is the
> > +		 * RID, but the high bit of the bus number is negated.
> > +		 * The sideband data provided to MSI controller b is the
> > +		 * RID, identity-mapped.
> > +		 * MSI controller c is not addressable.
> > +		 */
> > +		msi-map = <0x0000 &msi_a 0x8000 0x08000>,
> > +			  <0x8000 &msi_a 0x0000 0x08000>,
> > +			  <0x0000 &msi_b 0x0000 0x10000>;
> > +	};
> 
> they can be identical right? like
> 	<0x8000 &msi_a 0x0000 0x08000>,
>  	<0x8000 &msi_b 0x0000 0x08000>;

In general that would be valid, yes.

In this case two entries are required for MSI controller a because the
high bit passed to it is negated. This does not occur for MSI controller
b, so it only requires a single entry to describe the transformation.

Thanks,
Mark.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/