Re: [PATCH v5 12/20] memory: mtk-smi: Add gals support

[Yong Wu]

Hi Matthias,

   Gentle ping about this and the other mtk-smi part in this patchset.

   The memory part don't have its specific maintainer, normally we need
SoC maintain's help. Thus, For this file(memory/mtk-smi.c), your review
is needed before Joerg accept it.

    Appreciate in advance.

On Tue, 2019-01-01 at 11:55 +0800, Yong Wu wrote:
> In some SoCs like mt8183, SMI add GALS(Global Async Local Sync) module
> which can help synchronize for the modules in different clock frequency.
> It can be seen as a "asynchronous fifo". This is a example diagram:
> 
>             M4U
>              |
>          ----------
>          |        |
>      gals0-rx   gals1-rx
>          |        |
>          |        |
>      gals0-tx   gals1-tx
>          |        |
>         ------------
>          SMI Common
>         ------------
>              |
>   +-----+--------+-----+- ...
>   |     |        |     |
>   |  gals-rx  gals-rx  |
>   |     |        |     |
>   |     |        |     |
>   |  gals-tx  gals-tx  |
>   |     |        |     |
> larb1 larb2   larb3  larb4
> 
> GALS only help transfer the command/data while it doesn't have the
> configuring register, thus it has the special "smi" clock and doesn't
> have the "apb" clock. From the diagram above, we add "gals0" and
> "gals1" clocks for smi-common and add a "gals" clock for smi-larb.
> 
> This patch adds gals clock supporting in the SMI. Note that some larbs
> may still don't have the "gals" clock like larb1 and larb4 above.
> 
> This is also a preparing patch for mt8183 which has GALS.
> 
> Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
> ---
>  drivers/memory/mtk-smi.c | 36 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 36 insertions(+)
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