From mboxrd@z Thu Jan 1 00:00:00 1970 From: nicolas.pitre@linaro.org (Nicolas Pitre) Date: Sat, 28 Nov 2015 12:34:23 -0500 (EST) Subject: [PATCH 5/5] arm: boot: store ATAGs structure into DT "/chosen/linux,atags" entry In-Reply-To: <20151128123328.GC30871@n2100.arm.linux.org.uk> References: <20150713131902.GH26485@atomide.com> <20151127132722.GA30871@n2100.arm.linux.org.uk> <20151127195148.GB30871@n2100.arm.linux.org.uk> <11537945.4HX4Y84tjV@wuerfel> <20151128123328.GC30871@n2100.arm.linux.org.uk> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, 28 Nov 2015, Russell King - ARM Linux wrote: > On Fri, Nov 27, 2015 at 06:28:50PM -0500, Nicolas Pitre wrote: > > On Fri, 27 Nov 2015, Arnd Bergmann wrote: > > > > > I don't mind creating the /proc/atags compatibility hack from the kernel > > > for a DT based N700 kernel, as long as we limit it as much as we can > > > to the machines that need it. Leaving a board file for the N700 in place > > > that contains the procfs code (and not much more) seems reasonable > > > here, as we are talking about a board specific hack and the whole point > > > appears to be running unmodified user space. > > > > > > Regarding how to get the data into the kernel in the first place, my > > > preferred choice would still be to have an intermediate bootloader > > > such as pxa-impedance-matcher, but I won't complain if others are > > > happy enough about putting it into the ATAGS compat code we already > > > have, as long as it's limited to the boards we know need it. > > > > Assuming you have a N700 board file for special procfs code, then why > > not getting at the atags in memory where the bootloader has put them > > directly from that same board file? This way it'll really be limited to > > the board we know needs it and the special exception will be contained > > to that one file. Amongst the machine specific hooks, there is one that > > gets invoked early during boot before those atags are overwritten. > > I've already suggested that. Good. And Arnd likes the idea too. So we might be converging at last which is a good thing. Nicolas