From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Subject: Re: [PATCH] arm64: dts: marvell: armada-37xx: reserve memory for ATF Date: Mon, 23 Apr 2018 14:49:40 +0200 Message-ID: <20180423144940.64fa884d@windsurf> References: <20180421140342.25082-1-miquel.raynal@bootlin.com> <20180421161859.22d1ed18@windsurf> <20180423103127.5b9ac041@xps13> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180423103127.5b9ac041@xps13> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Miquel Raynal Cc: Mark Rutland , Andrew Lunn , Jason Cooper , devicetree@vger.kernel.org, Antoine Tenart , Catalin Marinas , Gregory Clement , Will Deacon , Maxime Chevallier , Nadav Haklai , Rob Herring , Victor Gu , linux-arm-kernel@lists.infradead.org, Sebastian Hesselbarth List-Id: devicetree@vger.kernel.org Hello, On Mon, 23 Apr 2018 10:31:27 +0200, Miquel Raynal wrote: > > Shouldn't this be done automatically by the bootloader, before passing > > the DTB to the kernel ? > > I am working with a 2017.09 mainline U-Boot. > > I did not know the bootloader was supposedly in charge of that. I thought it should be the case, but I indeed see nothing in U-Boot that does that, except for OMAP2 platforms. > But what if it fails doing it? Well if something fails in the boot process, the platform fails to boot. I find this question a bit weird/silly. It's like "and what if the user used the wrong DT for the wrong platform ?" > Fixing the bootloader is one thing, I assume very few people would > update it. Is it worth keeping this in Linux DT? The issue I see with having this in the Linux DT is that depending on the bootloader, the memory area that is used to keep the PSCI firmware may very well be different. It's really not a property of the HW itself, but a pure software choice of the bootloader. For example, are you sure the mainline U-Boot puts the PSCI firmware at the same place as the vendor U-Boot ? What are other platforms doing to solve this problem ? Best regards, Thomas -- Thomas Petazzoni, CTO, Bootlin (formerly Free Electrons) Embedded Linux and Kernel engineering https://bootlin.com From mboxrd@z Thu Jan 1 00:00:00 1970 From: thomas.petazzoni@bootlin.com (Thomas Petazzoni) Date: Mon, 23 Apr 2018 14:49:40 +0200 Subject: [PATCH] arm64: dts: marvell: armada-37xx: reserve memory for ATF In-Reply-To: <20180423103127.5b9ac041@xps13> References: <20180421140342.25082-1-miquel.raynal@bootlin.com> <20180421161859.22d1ed18@windsurf> <20180423103127.5b9ac041@xps13> Message-ID: <20180423144940.64fa884d@windsurf> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hello, On Mon, 23 Apr 2018 10:31:27 +0200, Miquel Raynal wrote: > > Shouldn't this be done automatically by the bootloader, before passing > > the DTB to the kernel ? > > I am working with a 2017.09 mainline U-Boot. > > I did not know the bootloader was supposedly in charge of that. I thought it should be the case, but I indeed see nothing in U-Boot that does that, except for OMAP2 platforms. > But what if it fails doing it? Well if something fails in the boot process, the platform fails to boot. I find this question a bit weird/silly. It's like "and what if the user used the wrong DT for the wrong platform ?" > Fixing the bootloader is one thing, I assume very few people would > update it. Is it worth keeping this in Linux DT? The issue I see with having this in the Linux DT is that depending on the bootloader, the memory area that is used to keep the PSCI firmware may very well be different. It's really not a property of the HW itself, but a pure software choice of the bootloader. For example, are you sure the mainline U-Boot puts the PSCI firmware at the same place as the vendor U-Boot ? What are other platforms doing to solve this problem ? Best regards, Thomas -- Thomas Petazzoni, CTO, Bootlin (formerly Free Electrons) Embedded Linux and Kernel engineering https://bootlin.com