<div dir="auto"><div dir="auto"><div dir="auto">Hey,</div><div dir="auto">I believe this patch can be merged as is. According to Sricharan R. [1]:</div><div dir="auto"><span style="font-family:sans-serif;font-size:12.8px">"</span><span style="font-family:sans-serif;font-size:12.8px">It is [sleep clk] derived from a 48M wifi refclk</span><br style="font-family:sans-serif;font-size:12.8px"><br style="font-family:sans-serif;font-size:12.8px"><span style="font-family:sans-serif;font-size:12.8px">48M wifi ref clk -> [/2 divider] -> [/750 divider] -> sleep_clk (32000)"</span></div></div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto">[1] <a href="https://patchwork.kernel.org/comment/22721613/">https://patchwork.kernel.org/comment/22721613/</a><br></div><div dir="auto"><br></div><div class="gmail_quote"><div dir="ltr" class="gmail_attr">пт, 17 мая 2019 г., 11:16 Павел <<a href="mailto:be.dissent@gmail.com" rel="noreferrer noreferrer noreferrer" target="_blank">be.dissent@gmail.com</a>>:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="auto"><div><br></div><div dir="auto"><br><div class="gmail_quote" dir="auto"><div dir="ltr" class="gmail_attr">чт, 16 мая 2019 г., 15:22 Sven Eckelmann <<a href="mailto:sven@narfation.org" rel="noreferrer noreferrer noreferrer noreferrer" target="_blank">sven@narfation.org</a>>:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Tuesday, 14 May 2019 15:42:18 CEST Pavel Kubelun wrote:<br>
> +--- a/arch/arm/boot/dts/qcom-ipq4019.dtsi<br>
> ++++ b/arch/arm/boot/dts/qcom-ipq4019.dtsi<br>
> +@@ -141,9 +141,9 @@<br>
> + };<br>
> + <br>
> + clocks {<br>
> +- sleep_clk: sleep_clk {<br>
> ++ sleep_clk: gcc_sleep_clk_src {<br>
> + compatible = "fixed-clock";<br>
> +- clock-frequency = <32768>;<br>
> ++ clock-frequency = <32000>;<br>
> + #clock-cells = <0>;<br>
> + };<br>
<br>
On Thursday, 16 May 2019 13:18:14 CEST Павел wrote:<br>
[...]<br>
> > And maybe some of these guys also know how to find the ipq40xx clock<br>
> > controller reference or hardware reference. Because I was only able to<br>
> > verify<br>
> > for IPQ8072 that it had a 32.768 KHz sleep clock. But the<br>
> ><br>
> <br>
> If you are completely sure about that, then I guess that they have<br>
> (un)intentionally messed with the clock in QSDK, because they state that<br>
> ipq807x has the same 32000 khz crystal.<br>
> <a href="https://source.codeaurora.org/quic/qsdk/oss/kernel/linux-msm/tree/arch/arm64/boot/dts/qcom/qcom-ipq807x-soc.dtsi?h=eggplant#n2055" rel="noreferrer noreferrer noreferrer noreferrer noreferrer noreferrer" target="_blank">https://source.codeaurora.org/quic/qsdk/oss/kernel/linux-msm/tree/arch/arm64/boot/dts/qcom/qcom-ipq807x-soc.dtsi?h=eggplant#n2055</a><br>
<br>
Confidence is the wrong word. I can only state that this is written in <br>
80-YA727-13 Rev. D (IPQ8072.AP.HK07). Same for other devices like <br>
IPQ8078 AP.HK02, IPQ8074 AP.HK01, ...<br>
<br>
But I found in the same document that they call it the "32 KHz sleep clock in" <br>
in one section and and in another table "32.768 KHz sleep clock input to the <br>
IPQ8072" (next to the name "...32K..."). So it is now to the reader to find <br>
out what they meant here in which reference document. So maybe they also meant <br>
32.768 KHz when in the IPQ4019 Watchdog document when they wrote 32 Khz sleep <br>
clock... who knows.<br></blockquote></div></div><div dir="auto"><br></div><div dir="auto"><div style="font-family:sans-serif" dir="auto">Okay, here what I've found in oem firmware (Zyxel nbg6617)</div><div dir="auto" style="font-family:sans-serif"><br></div><div dir="auto" style="font-family:sans-serif">There are 2 clocks related to timer in oem firmware:</div><div dir="auto" style="font-family:sans-serif">1. gcc_sleep_clk_src - 32.000</div><div dir="auto" style="font-family:sans-serif"> ^---USB3 sleep clock</div><div dir="auto" style="font-family:sans-serif"> ^---USB2 sleep clock</div><div dir="auto" style="font-family:sans-serif">2. wifi_rtc_clk_src - 32.768</div><div dir="auto" style="font-family:sans-serif"> ^---wcnssN sleep clock<br></div><div dir="auto" style="font-family:sans-serif"> ^---wcnssN sleep clock<br></div><div dir="auto" style="font-family:sans-serif"><br></div><div dir="auto" style="font-family:sans-serif">In upstream we don't have wifi_rtc clk and all mentioned childs are connected to sleep clk.</div><div dir="auto" style="font-family:sans-serif"><br></div><div dir="auto" style="font-family:sans-serif">So sleep clock at 32000 rate looks like some kind of a workaround and not to break wifi they introduced a separate clock for that, the one that really represents the hardware.</div><div dir="auto" style="font-family:sans-serif"><br></div><div dir="auto" style="font-family:sans-serif">I'll drop the sleep clock rate change in the next version of patchset since we don't need that kind of workaround for now.</div></div><div dir="auto"><br></div><div dir="auto"><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<br>
My gut feeling (sorry, not an HW guy) tell me that they are just using a <br>
32.768 KHz clock (from a standard 32.768 KHz oscillator) in all these products <br>
and just shortened it to 32K at some point in the document. And now Gopinath <br>
Sekar wrote 32000 instead of 32768. But I absolutely don't know what actually <br>
is there in HW.<br>
<br>
Kind regards,<br>
Sven<br>
<br>
[1] <a href="https://source.codeaurora.org/quic/qsdk/oss/kernel/linux-msm/commit/?id=d92ec59973484acc86dd24b67f10f8911b4b4b7d" rel="noreferrer noreferrer noreferrer noreferrer noreferrer noreferrer" target="_blank">https://source.codeaurora.org/quic/qsdk/oss/kernel/linux-msm/commit/?id=d92ec59973484acc86dd24b67f10f8911b4b4b7d</a></blockquote></div></div></div>
</blockquote></div></div>