On Tue, Sep 27, 2016 at 06:24:09PM +0000, york sun wrote:
On 09/27/2016 10:51 AM, Tom Rini wrote:
On Tue, Sep 27, 2016 at 05:39:55PM +0000, york sun wrote:
Guys,
I want to discuss to rearrange the current CONFIG_* macros used by Freescale Layerscape SoCs. We have been encouraged to use CONFIG_SYS_* macros to define hardware setting, and other CONFIG_* macros for user setting. Clearly this has changed. Kconfig options are used for most user settings from now on. I am OK with it. But for existing CONFIG_SYS_* macros, we need a plan to either move them out of CONFIG_* name space, or move some to Kconfig, if that makes sense. Since most our CONFIG_SYS_* macros are cross platforms (including armv7 and armv8), if using Kconfig option, do we add another mach-fsl folder to host the Kconfig, or somewhere else? We also have macros cross ARM and PowerPC. So we either move them out of arch/, or duplicate them for both arch.
If we move them to another name space, for example SYS_FSL_*, do we want to move them out of config.h?
Any suggestion/comment?
Well, if something is cross-platform the code is somewhere cross-platform too, yes? For example, if anything DDR related makes sense to stay as CONFIG_SYS_FSL_... it could go in to drivers/ddr/fsl/Kconfig and be visible in both cases. Otherwise <asm/arch/fsl_ddr.h> and SYS_FSL_... (or whatever makes sense, looking at the am33xx and mx6 cases, there's no SYS_ type prefix on the defines, just the IP block names) for the defines.
The benefit of keeping things together is easier to add a different SoC. For example, when we have LS2080A and need to add LS1046A, we pay attention to the difference. If the settings are scattered into IP drivers, it is not that obvious to track.
Looking at am33xx, it doesn't use many Kconfig options, but a lot in hardware*.h files. I need to see if we can do the same way.
It's an imperfect implementation, but yes, between arch/arm/cpu/armv7/omap-common/, am33xx/ and omap*/ we have a large number of IP blocks that have been evolving over time in a similar way to the FSL blocks I suspect. I also suspect there should be a bit more in Kconfig than is there.