Hi Tom, On Mon, Dec 10, 2012 at 9:05 AM, Tom Warren <twarren.nvi...@gmail.com> wrote: > Simon, > > On Sat, Dec 8, 2012 at 1:00 PM, Simon Glass <s...@chromium.org> wrote: >> Hi, >> >> On Tue, Dec 4, 2012 at 2:41 PM, Stephen Warren <swar...@wwwdotorg.org> wrote: >>> On 12/04/2012 01:40 PM, Lucas Stach wrote: >>>> Hi Tom, >>>> >>>> Am Dienstag, den 04.12.2012, 13:22 -0700 schrieb Tom Warren: >>>> [...] >>>>> >>>>>> >>>>>>> +#define V_NS16550_CLK 216000000 /* 216MHz >>>>>>> (pllp_out0) */ >>>>>> >>>>>> I thought PLL_P ran at 408MHz on Tegra30? The kernel certainly sets it >>>>>> up that way. >>>>> >>>>> See my previous reply. In the internal U-Boot repo I ported from, PLLP >>>>> was initially set to 216MHz, then sped up to 408MHz. When this first >>>>> round of patches is in, I can address going to 408MHz first thing. >>>>> >>>> Is running the PLL_P at 408MHz something which requires a lot of work? >>>> If not, please do this and fold it into this patchset. It doesn't look >>>> too nice adding things to upstream which have to be changed/removed >>>> immediately after going in. >>> >>> Naively I'd have to agree here; it seems that programming the PLL for >>> the correct rate would probably "just work" right from the outset? After >>> all, if the code runs OK with the higher rate enabled a little later in >>> boot, I see no reason it shouldn't run OK with that exact same rate the >>> whole way through. >> >> From memory, the problem was originally that we wanted to be able to >> configure the PLL speed at run time, because we we using both speeds. >> Since T30 now apparently only uses 408MHz, it should be ok to set it >> once and hard-code it. >> >> Regards, >> Simon >> > Thanks. As I remember it, it was a user-config option for early T30 > boards to run at 216MHz or 408MHz. The 408MHz PLLP change generated a > lot of email traffic on what the best output clocks (pllp_out1 thru 4) > would be for the various periphs, subclocks, etc. > > When I did the original bringup for upstream U-Boot on my (older) > Cardhu, I wanted to start at 216MHz first, then step up to 408MHz when > I was at a stable point. Much like when I rebuilt my Mustang - I took > it out around the block first, to be sure everything was working OK > before I took it on the highway ;) > > I'm running OK at 408MHz on my Cardhu T33. I'll resubmit V3 of the > patchset in the next day or so.
Sounds good, thanks. It would be good to get this in. Regards, Simon > > Thanks, > > Tom >>> >>> _______________________________________________ >>> U-Boot mailing list >>> U-Boot@lists.denx.de >>> http://lists.denx.de/mailman/listinfo/u-boot _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
