From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Horman Date: Wed, 08 Jul 2015 02:05:15 +0000 Subject: Re: [PATCH] ARM: shmobile: rcar-gen2: CONFIG_ARM_ARCH_TIMER is always set Message-Id: <20150708020511.GB14992@verge.net.au> List-Id: References: <1436277927-20159-1-git-send-email-geert+renesas@glider.be> In-Reply-To: <1436277927-20159-1-git-send-email-geert+renesas@glider.be> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org Hi Magnus, On Wed, Jul 08, 2015 at 10:40:18AM +0900, Magnus Damm wrote: > Hi Simon, > > On Wed, Jul 8, 2015 at 10:16 AM, Simon Horman wrote: > > On Wed, Jul 08, 2015 at 12:34:47AM +0900, Magnus Damm wrote: > >> Hi Geert, > >> > >> On Wed, Jul 8, 2015 at 12:21 AM, Geert Uytterhoeven > >> wrote: > >> > Hi Magnus, > >> > [snip] > >> > HAVE_ARM_ARCH_TIMER used to be user-selectable, but your patch > >> > "ARM: shmobile: Select HAVE_ARM_ARCH_TIMER from Kconfig" made that > >> > unconditional for R-Car Gen2 and APE6 ;-) > >> > >> Ouch - my bad! That's not at all what I intended to do. > >> > >> I only wanted to express that R-Car Gen2 and APE6 come with arch timer > >> hardware, and in such case the user shall be able to select it. If > >> R-Car Gen2 or APE6 isn't selected then there is no point in exposing > >> such choice to the user. But obviously that wasn't what I ended up > >> doing... > >> > >> What would be a sane way to approach this? I think always enabling it > >> may not work for CA7-based SoCs from Renesas that at least used to > >> have setup issues with arch timer... > > > > Given the current arrangement in arch/arm/Kconfig: > > > > config HAVE_ARM_ARCH_TIMER > > bool "Architected timer support" > > depends on CPU_V7 > > select ARM_ARCH_TIMER > > select GENERIC_CLOCKEVENTS > > help > > This option enables support for the ARM architected timer > > > > It seems to me that a good solution would be to (go back to?) > > * not selecting HAVE_ARM_ARCH_TIMER in arch/arm/mach-shmobile/Kconfig and; > > * enabling HAVE_ARM_ARCH_TIMER in defconfigs as appropriate > > That is one idea for sure. > > > Perhaps that can be achieved by dropping/reverting > > * 731bde02f622 ARM: shmobile: Select HAVE_ARM_ARCH_TIMER from Kconfig > > * b46ddcdf484c ARM: shmobile: Drop HAVE_ARM_ARCH_TIMER from defconfig > > > > At this stage I have not sent pull-requests for the above so I would > > be feasible for me to simply drop them if we agree on that. > > >From my side simply dropping seems the easiest way forward. Me too. Lets sit on this for a day or so and see what Geert and others have to say. > This reminds me of the good old "generating kernel configuration from > DT", so in the future if we may be able to do so then that could > perhaps that shmobile_defconfig bit for us. :) > > FWIW, I assumed that your patch would achieve its goal. The arrangement of > > HAVE_ARM_ARCH_TIMER and ARM_ARCH_TIMER seems entirely intuitive to me. But > > I'm reluctant to advise opening that Pandora's box. > > Completely agree, but from my side you need to s/intuitive/counter > intuitive/g. =) Yes, sorry for that editing error.