From mboxrd@z Thu Jan 1 00:00:00 1970 From: maxime.ripard@free-electrons.com (Maxime Ripard) Date: Sat, 23 May 2015 10:18:47 +0200 Subject: [PATCH v8 14/16] ARM: dts: Introduce STM32F429 MCU In-Reply-To: <1432289231.3929.60.camel@pengutronix.de> References: <1431158038-3813-1-git-send-email-mcoquelin.stm32@gmail.com> <2282066.NWoIT9ZyLc@wuerfel> <13641152.Yt4ZI3oT6L@wuerfel> <1432285588.3929.28.camel@pengutronix.de> <20150522091822.GF8557@lukather> <1432289231.3929.60.camel@pengutronix.de> Message-ID: <20150523081847.GJ8557@lukather> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Philipp, On Fri, May 22, 2015 at 12:07:11PM +0200, Philipp Zabel wrote: > Am Freitag, den 22.05.2015, 11:18 +0200 schrieb Maxime Ripard: > > On Fri, May 22, 2015 at 11:06:28AM +0200, Philipp Zabel wrote: > > > > In the probe function, it would check the number of reg resources. > > > > If a single resource is passed, it would take it, else it would look > > > > the one named "reset". > > > > The driver and bindings would be the same for the two families, and > > > > the bindings would be backward compatible with sunxi ones. > > > > > > > > Philip, Arnd, what do you think? > > > > > > I'm not a fan of describing the register layout in the device tree as > > > detailed as the sunxi bindings do. I'd prefer the reg property to > > > describe the device's register address space with one entry per > > > contiguous block of registers. > > > > That's exactly what we do. > > Sorry, what I mean is 'as detailed as reusing the sunxi bindings for > stm32xx here would do'. I don't know enough about the Allwinner register > layouts to form an opinion. > > The STM32F427xx/STM32F429xx manual, Table 13. "STM32F427xx and > STM32F429xx register boundary addresses" contains this entry: > Bus Boundary address Peripheral > AHB1 0x40023800-0x400238bf RCC > > And that's how I'd expect it to be described by the device tree: > > rcc: rcc at 40023800 { > compatible = "st,stm32-rcc"; > reg = <0x40023800 0xc0>; > }; It's pretty much what we do already. The thing is that our reset controllers are intertwined with our clock ones, so our reset controllers are usually taking only a few registers, and we can't use more than that since we have clocks in the registers around. > Instead of "reg = <0x40023810 0x20>" for the resets. Where in the > address range the reset, clock gate and clock configuration registers > reside could be derived from the compatible value. I agree on that, and if a generic solution was to be made like this, we could definitely use it. Maxime -- Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: