Re: [PATCH v2 3/9] spi: mtk-snfi: Add optional nfi_hclk which needed for MT7986

From: AngeloGioacchino Del Regno
Date: Wed Dec 07 2022 - 05:08:56 EST


Il 07/12/22 02:42, Xiangsheng Hou (侯祥胜) ha scritto:
Hi Angelo,

On Mon, 2022-12-05 at 15:21 +0100, AngeloGioacchino Del Regno wrote:
Il 05/12/22 07:57, Xiangsheng Hou ha scritto:
Add optional nfi_hclk which needed for MT7986.

Signed-off-by: Xiangsheng Hou <xiangsheng.hou@xxxxxxxxxxxx>

Is there any operation for which you need NFI_HCLK enabled, but at
the same time
PAD_CLK and/or NFI_CLK can be disabled?

No, for the new IP design on MT7986, will need the
PAD_CLK/NFI_CLK/NFI_HCLK enabled at the same time.

If NFI_HCLK and NFI_CLK must always be ON at the same time, adding
this clock to
spi-mtk-snfi.c is *not* an optimal way of doing things: you can, at
this point,
set NFI_HCLK as parent of NFI_CLK in the MT7986 clock driver instead,
without
making any addition to this driver at all.

For some IC, there may have only NFI_CLK/PAD_CLK, and have no NFI_HCLK,
this rely on IC design.


I've just checked clk-mt7986-infracfg and we can't reparent NFI1_CK, nor SPINFI1_CK
as they have xxxx_sel parents already, which are not common with the HCK.

You're right, the addition of the nfi_hclk clock is needed, which means that for
this commit, you get my


Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>


P.S.: Thanks for clarifying!

Regards,
Angelo