From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Date: Thu, 06 Jun 2013 16:53:43 +0000 Subject: Re: [PATCH 01/06] ARM: shmobile: Introduce SHMOBILE_FIXUP() helper Message-Id: <201306061853.44135.arnd@arndb.de> List-Id: References: <20130605073410.15758.37563.sendpatchset@w520> <20130605073418.15758.93704.sendpatchset@w520> <20130605192019.GG18614@n2100.arm.linux.org.uk> In-Reply-To: <20130605192019.GG18614@n2100.arm.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org On Wednesday 05 June 2013, Russell King - ARM Linux wrote: > On Wed, Jun 05, 2013 at 04:34:18PM +0900, Magnus Damm wrote: > > From: Magnus Damm > > > > Introduce SHMOBILE_FIXUP() as a helper function to > > allow boards to specify their memory base and size. > > No. I really don't like this idea (we've had people doing this in the > past and I went around removing all that crap, and adding command line > options into the defconfig files for those boards.) > > I also fail to understand why in 2013, some 11 years after ATAG stuff > was created, people still can't get pass correct information into > the kernel. > > It's exactly this kind of issue which makes me believe that stuff like > ACPI, UEFI and DT are doomed to fail on ARM because this kind of problem > constantly crops up time and time again. People have seem to have this > total inability to get the pre-kernel environment right. I think the problem in this case is that the pre-boot environment is essentially nothing but mask rom jumping into head-shmobile.S, which is something nobody else does. My understanding is that you can also put a regular u-boot, kexec or some other boot loader into the same place and get a running system with correct ATAGS or DT information. It's debatable whether booting the kernel directly without an upgradable boot loader is a good idea, but since Renesas have come to depend on this and it's been supported by Linux for ages (both on ARM and SH), I would certainly not ask them to remove support for that. What I think we can do however is move all that configuration into one place of the kernel that is fairly separate from everything else. head-shmobile.S already contains most of the special case, so how about adding a configuration option that enables both the head-shmobile.S code and contains the configuration for that in a submenu? Arnd From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Thu, 6 Jun 2013 18:53:43 +0200 Subject: [PATCH 01/06] ARM: shmobile: Introduce SHMOBILE_FIXUP() helper In-Reply-To: <20130605192019.GG18614@n2100.arm.linux.org.uk> References: <20130605073410.15758.37563.sendpatchset@w520> <20130605073418.15758.93704.sendpatchset@w520> <20130605192019.GG18614@n2100.arm.linux.org.uk> Message-ID: <201306061853.44135.arnd@arndb.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wednesday 05 June 2013, Russell King - ARM Linux wrote: > On Wed, Jun 05, 2013 at 04:34:18PM +0900, Magnus Damm wrote: > > From: Magnus Damm > > > > Introduce SHMOBILE_FIXUP() as a helper function to > > allow boards to specify their memory base and size. > > No. I really don't like this idea (we've had people doing this in the > past and I went around removing all that crap, and adding command line > options into the defconfig files for those boards.) > > I also fail to understand why in 2013, some 11 years after ATAG stuff > was created, people still can't get pass correct information into > the kernel. > > It's exactly this kind of issue which makes me believe that stuff like > ACPI, UEFI and DT are doomed to fail on ARM because this kind of problem > constantly crops up time and time again. People have seem to have this > total inability to get the pre-kernel environment right. I think the problem in this case is that the pre-boot environment is essentially nothing but mask rom jumping into head-shmobile.S, which is something nobody else does. My understanding is that you can also put a regular u-boot, kexec or some other boot loader into the same place and get a running system with correct ATAGS or DT information. It's debatable whether booting the kernel directly without an upgradable boot loader is a good idea, but since Renesas have come to depend on this and it's been supported by Linux for ages (both on ARM and SH), I would certainly not ask them to remove support for that. What I think we can do however is move all that configuration into one place of the kernel that is fairly separate from everything else. head-shmobile.S already contains most of the special case, so how about adding a configuration option that enables both the head-shmobile.S code and contains the configuration for that in a submenu? Arnd