[v2,1/1] arm64: dts: qcom: ipq6018: fix clock rates for GCC_USB0_MOCK_UTMI_CLK

Message ID 20231203154030.532880-1-amadeus@jmu.edu.cn
State New
Headers
Series [v2,1/1] arm64: dts: qcom: ipq6018: fix clock rates for GCC_USB0_MOCK_UTMI_CLK |

Commit Message

Chukun Pan Dec. 3, 2023, 3:40 p.m. UTC
  The clock provided by XO is 24MHz, not 20MHz.

Fixes: 5726079cd486 ("arm64: dts: ipq6018: Use reference clock to set dwc3 period")
Signed-off-by: Chukun Pan <amadeus@jmu.edu.cn>
---
Changes in v2:
* No changes, resend due to error link to other threads.

 arch/arm64/boot/dts/qcom/ipq6018.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

Comments

Krzysztof Kozlowski Dec. 3, 2023, 4:33 p.m. UTC | #1
On 03/12/2023 16:40, Chukun Pan wrote:
> The clock provided by XO is 24MHz, not 20MHz.

That does not look like XO, but GCC_USB0_MOCK_UTMI_CLK

> 
> Fixes: 5726079cd486 ("arm64: dts: ipq6018: Use reference clock to set dwc3 period")
> Signed-off-by: Chukun Pan <amadeus@jmu.edu.cn>
Best regards,
Krzysztof
  
Chukun Pan Dec. 5, 2023, 3:02 a.m. UTC | #2
> That does not look like XO, but GCC_USB0_MOCK_UTMI_CLK

I don't have the datasheet, but the reference clock (XO) is 24MHz, 
and I receive the following warning:
clk: couldn't set gcc_usb0_mock_utmi_clk clk rate to 20000000 (-22), current rate: 24000000

Thanks,
Chukun
  
Krzysztof Kozlowski Dec. 5, 2023, 7:02 a.m. UTC | #3
On 05/12/2023 04:02, Chukun Pan wrote:
>> That does not look like XO, but GCC_USB0_MOCK_UTMI_CLK
> 
> I don't have the datasheet, but the reference clock (XO) is 24MHz, 
> and I receive the following warning:
> clk: couldn't set gcc_usb0_mock_utmi_clk clk rate to 20000000 (-22), current rate: 24000000

Referencing XO in commit  msg is confusing. Anyway, answer to such error
is not necessarily change the clock rate. What if it must be 20 MHz? You
just ignore such requirement...

Best regards,
Krzysztof
  
Chukun Pan Dec. 6, 2023, 3:01 a.m. UTC | #4
> Referencing XO in commit  msg is confusing. Anyway, answer to such error
> is not necessarily change the clock rate. What if it must be 20 MHz? You
> just ignore such requirement..

The downstream QSDK kernel [1] and GCC_USB1_MOCK_UTMI_CLK are both 24MHz.
Judging from these commit [1][2], I think they forgot to make changes here.

1. https://git.codelinaro.org/clo/qsdk/oss/kernel/linux-ipq-5.4/-/commit/486c8485f59
2. https://github.com/torvalds/linux/commit/d1c10ab1494f09eb12fa6e58fc78bb28d44922ae

Thanks,
Chukun
  

Patch

diff --git a/arch/arm64/boot/dts/qcom/ipq6018.dtsi b/arch/arm64/boot/dts/qcom/ipq6018.dtsi
index 2399d16f147e..d114c8096347 100644
--- a/arch/arm64/boot/dts/qcom/ipq6018.dtsi
+++ b/arch/arm64/boot/dts/qcom/ipq6018.dtsi
@@ -621,7 +621,7 @@  usb3: usb@8af8800 {
 					  <&gcc GCC_USB0_MOCK_UTMI_CLK>;
 			assigned-clock-rates = <133330000>,
 					       <133330000>,
-					       <20000000>;
+					       <24000000>;
 
 			resets = <&gcc GCC_USB0_BCR>;
 			status = "disabled";