[U-Boot] [PATCH] arch: ifc: update the IFC IP input clock

[Prabhakar Kushwaha]

> -----Original Message-----
> From: Scott Wood
> Sent: Friday, September 09, 2016 6:05 AM
> To: Prabhakar Kushwaha <prabhakar.kushwaha at nxp.com>; york sun
> <york.sun at nxp.com>; u-boot at lists.denx.de
> Subject: Re: [PATCH] arch: ifc: update the IFC IP input clock
> 
> On 09/08/2016 07:05 PM, Prabhakar Kushwaha wrote:
> >
> >> -----Original Message-----
> >> From: york sun
> >> Sent: Thursday, September 08, 2016 9:22 PM
> >> To: Prabhakar Kushwaha <prabhakar.kushwaha at nxp.com>; u-
> >> boot at lists.denx.de; Scott Wood <scott.wood at nxp.com>
> >> Subject: Re: [PATCH] arch: ifc: update the IFC IP input clock
> >>
> >> On 09/08/2016 02:33 AM, Prabhakar Kushwaha wrote:
> >>
> >> <snip>
> >>
> >>>>> So better to print IP clock to avoid any confusion.
> >>>>> IFC output clock will be printed when it is actually being used during
> >>>> synchronous NOR, syn NAND.
> >>>>
> >>>> I am not against changing it to internal clock. But what are you going
> >>>> to print on the console? I think it is confusing to say IFC or local bus
> >>>> internal clock speed. Please also check how this clock is used and make
> >>>> sure arch.lbc_clk is still correct, after passing to Linux.
> >>>>
> >>> arch.lbc_clk is only being used for eLBC for device tree fixup.
> >>> And I checked the Linux eLBC driver. Looks like it is not using used.
> >>>
> >>
> >> If this clock is not used, can we drop it completely?
> >>
> >
> > From my point of view Yes.
> >
> > Scott, Please advice
> 
> Well, there is that patch from Matt Weber that is trying to guess the
> IFC frequency in order to use NWAIT...  Not sure if we'll end up
> actually using NWAIT 
(Prabhakar, can you answer my question of whether
> there is a better opcode to use with RNDOUT?) or ever sending a real
> RNDOUT, or if we'll ever care about these newer NAND chips on eLBC, but
> if U-Boot is currently writing the clock frequency into the device tree
> I don't see why we'd rip it out.
> 

IFC frequency means IP clock or IP output clock?

If IP clock then other patch for eLBC still valid.  
If there is possibility of this frequency may require for future flash. I agree we should keep device tree fix-up code for eLBC. 

For IFC: Code needs to be added for device tree fixup for PowerPC, ARM SoC. 
It is missing for now :(

Regarding RDNOUT, let me check and come back on the mail thread.

--prabhakar