Re: [PATCH v4 2/4] dt-bindings: mmc: sdhci-of-dwcmhsc: Add Sophgo SG2042 support

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On 2024/6/21 0:15, Jisheng Zhang wrote:
On Tue, Jun 18, 2024 at 04:38:30PM +0800, Chen Wang wrote:
From: Chen Wang <unicorn_wang@xxxxxxxxxxx>

SG2042 use Synopsys dwcnshc IP for SD/eMMC controllers.

SG2042 defines 3 clocks for SD/eMMC controllers.
- AXI_EMMC/AXI_SD for aclk/hclk(Bus interface clocks in DWC_mshc)
   and blck(Core Base Clock in DWC_mshc), these 3 clocks share one
   source, so reuse existing "core".
No, this seems not correct. This should be the "bus" clk, and your above
sentence "aclk/hclk(Bus interface clocks in DWC_mshc)" implies this clk is
for bus

- 100K_EMMC/100K_SD for cqetmclk(Timer clocks in DWC_mshc), so reuse
   existing "timer" which was added for rockchip specified.
- EMMC_100M/SD_100M for cclk(Card clocks in DWC_mshc), add new "card".
I think this is "core" clk, no? Plz check which internal clks' clock
source is the so called EMMC_100M/SD_100M.

hi, Jisheng,

Just want to double-confirm, corresponding to the definition of clock in the dwc-mshc specification, what's the "core" clock in the snps,dwcmshc-sdhci.yaml?

I get following clock definitions in user-guide of dwc-mshc specification, in section 1.8 "Speed and Clock Requirements"

- 1.8.1 Bus Interface Clocks,which are aclk and m_hclk/hclk
- 1.8.2 Timer Clocks,which are tmclk,cqetmclk
- 1.8.3 Card Clocks, whichi is cclk
- 1.8.4 Core Base Clock,which is bclk

I used to think "core" is "Core Base Clock".

[......]





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