On Wed, May 24, 2023 at 05:00:02PM +0800, Xingyu Wu wrote:
> On 2023/5/23 19:28, Conor Dooley wrote:
> > On Tue, May 23, 2023 at 01:10:06PM +0200, Torsten Duwe wrote:
> >> On Tue, 23 May 2023 09:28:39 +0100
> >> Conor Dooley <conor.doo...@microchip.com> wrote:
> >>
> >> > On Tue, May 23, 2023 at 10:56:43AM +0800, Xingyu Wu wrote:
> >> > > On 2023/5/19 22:16, Conor Dooley wrote:
> >> > > > On Fri, May 19, 2023 at 03:57:33PM +0200, Torsten Duwe wrote:
> >> > > >> On Fri, May 12, 2023 at 10:20:30AM +0800, Xingyu Wu wrote:
> >> > > >> [...]
> >>
> >> > > >> > +/* PLL clocks */
> >> > > >> > +#define JH7110_CLK_PLL0_OUT 0
> >> > > >> > +#define JH7110_CLK_PLL1_OUT 1
> >> > > >> > +#define JH7110_CLK_PLL2_OUT 2
> >> > > >>
> >> > > >> In U-Boot commit 58c9c60b Yanhong Wang added:
> >> > > >>
> >> > > >> +
> >> > > >> +#define JH7110_SYSCLK_PLL0_OUT 190
> >> > > >> +#define JH7110_SYSCLK_PLL1_OUT 191
> >> > > >> +#define JH7110_SYSCLK_PLL2_OUT 192
> >> > > >> +
> >> > > >> +#define JH7110_SYSCLK_END 193
> >> [...]
> >> > > > Ohh, that's not good.. If you pass the U-Boot dtb to Linux it
> >> > > > won't understand the numbering. The headers are part of the
> >> > > > dt-binding :/
> >>
> >> In fact, the clock index >= 190 makes linux hang on boot, waiting with
> >> EPROBE_DEFER for every device's clock, because the sysclk driver errors
> >> out with EINVAL (jh7110_sysclk_get()).
> >
> > Yup, that's about what I expected to happen.
> >
> >> > > Because PLL driver is separated from SYSCRG drivers in Linux, the
> >> > > numbering starts from 0. But in Uboot, the PLL driver is included
> >> > > in the SYSCRG driver, and the number follows the SYSCRG.
> >> >
> >> > Unfortunately, how you choose to construct your drivers has nothing to
> >> > do with this.
> >> > These defines/numbers appear in the dts and are part of the DT ABI.
> >> > The same dts is supposed to work for Linux & U-Boot.
> >>
> >> The JH7110 has 6 blocks of 64k iomem in that functional area:
> >> {SYS,STG,AON} x {CRG,SYSCON}. None of these has 190 clocks.
> >> The good news: the current DTS, as proposed here and in U-Boot master,
> >> provides nodes for all 6 entities. The bad news is that the clock
> >> assignments to those nodes and their numbering is messed up.
> >>
> >> AFAICT PLL{0,1,2} _are_ generated in SYS_SYSCON and thus U-Boot gets it
> >> wrong, in addition to the erroneous DTS.
> >
> > The numbers are kinda hocus-pocus anyway, they are just made up since the
> > clock numbering usually isn't something with a nice TRM to go and
> > reference (unlike interrupts which usually are documented in that way).
> > It is very helpful to make them aligned some register/bit positions or,
> > but that is not required.
> > IOW U-Boot is not wrong per se to use 190 instead of 0, but it is wrong
> > to have different numbers in both places.
> >
> > It sounds like you're saying that (and I have not looked) the U-Boot dts
> > actually has structural difference w.r.t. what provides which clock?
> > If so, that'll need to be fixed independently of the numbering problem.
> >
> > Otherwise Xingyu & Yanhong should coordinate on which is the "correct"
> > way of doing things & do it in both places.
> >
>
> Oh, unfortunately, the 7110 can not support to mix the uboot dtb and linux
> dtb up.What does "cannot support" mean? It's normal and desirable for the same dtb to be usable for both. The Linux kernel's dt-bindings are used for multiple projects, not just Linux - it'd be silly for U-Boot, FreeBSD etc etc to go off and each have their open set of (incompatible) bindings. > If boot the Linux and should use the linux dtb instead of the uboot dtb. > Because all clock ids and reset ids in Linux and Uboot are different include > PLL, and some modules can work in Linux but not in uboot. What do you mean by "modules"? It is fine for either Linux or U-Boot to not have drivers for particular peripherals - for example, there might be no driver for your camera related bits in U-Boot, or for controlling DRAM in Linux. The description of the hardware should not change though, as the hardware has not. > I suggest to boot Linux with its own linux dtb. I suggest to make sure that you can use the same dtb for both. Thanks, Conor.
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