On Wed, Jul 23, 2014 at 5:55 PM, Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote: > Hi, > > On Mon, Jul 21, 2014 at 10:46:06PM +0800, Chen-Yu Tsai wrote: >> Hi, >> >> On Fri, Jul 18, 2014 at 4:07 PM, Maxime Ripard >> <maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote: >> > Hi, >> > >> > On Mon, Jul 14, 2014 at 03:32:13PM +0800, Chen-Yu Tsai wrote: >> >> This patch introduces the driver for the RTC in the Allwinner A31 and >> >> A23 SoCs. >> >> >> >> Unlike the RTC found in A10/A20 SoCs, which was part of the timer, the >> >> RTC in A31/A23 are a separate hardware block, which also contain a few >> >> controls for the RTC block hardware (a regulator and RTC block GPIO pin >> >> latches), while also having separate interrupts for the alarms. >> > >> > Do you plan on supporting those at some point? >> >> I haven't seen any devices use the regulator (which has an output pin). >> I suppose we shouldn't add drivers for things we can't verify. >> As for the GPIO pin latches, I'll have to experiment some more to figure >> out what they do exactly. > > Ok. > >> > It's also worth noting that the first registers are supposed to >> > control the source of the low frequency oscillator in the SoC, which >> > will probably be the most troublesome, since we need these clocks very >> > early on. >> >> That's true. I suppose the bootloader configures this. IIRC I've seen >> code for this in boot0 or boot1 from Allwinner. I can't find the equivalent >> for our sun4i u-boot though. > > Do you know what was the bootloader configuring it to? I checked this some time ago, when I started to look at the sunxi clock code. For all the devices (sun6/7/8i) I've checked, the system is configured to use the external 32.768k oscillator. > I don't really know how we can deal with this in a nice way, but I > guess it's not so urgent. I agree. I will look at the BROM (for sun4/7i) and boot0 (sun6i) for signs of when it is configured. Then we can determine if we need to implement it somewhere. [...] ChenYu -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
