Messages in this thread | | | Date | Wed, 2 Nov 2022 21:49:49 -0500 | From | Bjorn Andersson <> | Subject | Re: [PATCH v1] clk: qcom: gcc-sc8280xp: add cxo as parent for gcc_ufs_ref_clkref_clk |
| |
On Wed, Nov 02, 2022 at 10:26:13AM +0100, Johan Hovold wrote: > On Wed, Nov 02, 2022 at 02:15:26PM +0530, Shazad Hussain wrote: > > On 11/2/2022 1:43 PM, Johan Hovold wrote: > > > > Right, but if the PHYs really requires CX and it is not an ancestor of > > > the refclk then this should be described by the binding (and not be > > > hidden away in the clock driver). > > > This makes sense, will be posting v2 post for the same. > > I assume this should use the Fixes tag then ! > > Yeah, I guess to you can add a fixes tag for the commits adding support > for sc8280xp to the UFS PHY binding and driver. > > But please do check with the hardware documentation first so we get this > right this time. > > I've already asked Bjorn to see what he can dig out as it is still not > clear how the two "card" refclocks (GCC_UFS_CARD_CLKREF_CLK and > GCC_UFS_1_CARD_CLKREF_CLK) are supposed to be used. >
We've come full circle and Shazad's patch came from that discussion :)
In line with the downstream dts, we have GCC_UFS{,_1}_CARD_CLKREF_CLK providing a reference clock to the two phys. Then GCC_UFS_REF_CLKREF_CLK feeds the UFS refclock pads (both of them), which connect to the memory device(s).
In other words, GCC_UFS{,_1}_CARD_CLKREF_CLK should be "ref" in respective phy.
GCC_UFS_REF_CLKREF_CLK is the clock to the devices, but as we don't represent the memory device explicitly it seems suitable to use as "ref_clk" in the ufshc nodes - which would then match the special handling of the "link clock" in the UFS driver.
All three clocks are sourced off the CXO pad, so I would like this patch to cover at least all of these. And
Fixes: d65d005f9a6c ("clk: qcom: add sc8280xp GCC driver")
seems to be in order for such patch.
@Johan, would you mind writing a dts patch flipping the clocks around and Shazad can update this patch?
Regards, Bjorn
| |