Hi Łukasz, Am Montag, 24. Juli 2017, 11:23:05 CEST schrieb Łukasz Majewski: > On 07/24/2017 10:59 AM, Heiko Stübner wrote: > > Am Montag, 24. Juli 2017, 16:38:52 CEST schrieb Andy Yan: > >> Hi Philipp: > >> > >> On 2017年07月21日 18:55, Dr. Philipp Tomsich wrote: > >>>> On 21 Jul 2017, at 04:33, Andy Yan <andy....@rock-chips.com> wrote: > >>>> > >>>> Hi: > >>>> > >>>> On 2017年07月19日 04:35, Philipp Tomsich wrote: > >>>>> Here's a series that has a lot going on, but I didn't want to split it > >>>>> to allow everyone to understand the motivation between some of the > >>>>> changes to the SPL/TPL framework. The short summary of this is > >>>>> "enablement for DRAM init on the RK3368 with everything else that's > >>>>> necessary to do it using OF_PLATDATA in TPL". > >>>>> > >>>>> Enabling the RK3368 created a few more challenges that I'd expected: > >>>>> - I needed different stack locations, text addresses and sizes for > >>>>> > >>>>> TPL and SPL > >>>>> > >>>>> - the TPL stage was to use OF_PLATDATA and SPL was to use full > >>>>> OF_CONTROL > >>>>> - with the RK3368 TPL stage, there was a need to extend the > >>>>> back-to-bootrom > >>>>> > >>>>> support for Rockchip to AArch64 > >>>>> > >>>>> - I wanted to start folding some of the Rockchip specific SPL > >>>>> support > >>>>> > >>>>> (i.e. back-to-bootrom) back into the general SPL framework to > >>>>> allow > >>>>> using it as a general boot method > >>>> > >>>> I have a confusion here: according to the README.TPL, TPL is Third > >>>> Program Loader, which loaded by the SPL. So I think it should run after > >>>> the SPL. But from RK3188 and RK3368 TPL implementation , they all run > >>>> before SPL.Maybe it is my misunderstanding, hope to get some > >>>> guidance.:-)> > >>> > >>> I think you are right and most Rockchip boards have been using this the > >>> wrong way around. > > > > Actually at first I also had the ordering of SPL -> TPL -> uboot for > > rk3188 > > but after discussions with Simon and Tom Rini, the opinion was that TPL > > stands for "tiny" program loader and should run before the full SPL. > > Has something changed since: > > http://www.denx.de/wiki/pub/U-Boot/MiniSummitELCE2013/tpl-presentation.pdf > > I've always thought that we do have SPL -> TPL -> u-boot -> Linux > > If there was a change, then: > > 1. The TPL name is a bit misleading (considering the above > presentation/status) > > 2. IMHO the code running before SPL (to do some _real_ early init) > should be named more descriptive like PreSPL.
I've gone back and looked up the previous discussion. It was part of a thread where we only included Tom later on to clarify spl/tpl usage, so there is no list-reference, but I guess I can just quote the part: ----------------- 8< ------------------- Am Donnerstag, 26. Januar 2017, 12:57:40 CEST schrieben Tom Rini: > On Thu, Jan 26, 2017 at 07:23:25AM -0700, Simon Glass wrote: > > +Tom for question below. > > > > Hi Heiko, > > > > On 17 December 2016 at 15:51, Heiko Stübner <he...@sntech.de> wrote: > > > Hi, > > > > > > Am Samstag, 17. Dezember 2016, 09:57:51 schrieb Simon Glass: > > >> I cannot see the .S code in that tree. If it is a few instructions > > >> then it is fine. But if it is a lot of code I question why it cannot > > >> be written mostly in C? > > > > > > The .S was just my question to Kever how he envisioned this "preloader" > > > being implemented. Right now all my parts are fully C-based. > > > > > >> Using TPL seems OK to me. But from my understanding TPL runs before > > >> SPL. So the sequence should be: TPL -> SPL -> U-Boot. This makes some > > >> sense because SPL is a more full-featured loader, and TPL is just a > > >> mini-loader to get the SPL running. > > > > > > hmm, I think SPL -> TPL -> U-Boot would be the correct order :-) > > > Based on the TPL being the "tertiary program loader" where the SPL only > > > is the "secondary program loader" and based on the slides from 2013 in > > > [0].> > > That seems wrong to me. A secondary load loads the primary loader, > > which surely means that the tertiary should load the secondary, i.e. > > > > I think it should be: > > 2 loads 1 (SPL loads U-Boot) > > 3 loads 2 which loads 1 (TPL loads SPL which loads U-Boot) > > > > The alternative is: > > 2 loads 3 which loads 1 > > > > which seems really odd. > > > > Note that PowerPC appears to use TPL->SPL->U-Boot when I last looked > > at it. Of course I could be wrong. > > Yes, naming is hard. TPL (which is maybe better thought of as Tiny not > Tertiary) loads SPL loads U-Boot. ----------------- 8< ------------------- Heiko _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
