* [PATCH v2] arm64: dts: imx8mp: use correct clock for eqos timestamping counter
@ 2023-07-21 3:51 ` Johannes Zink
0 siblings, 0 replies; 5+ messages in thread
From: Johannes Zink @ 2023-07-21 3:51 UTC (permalink / raw)
To: Rob Herring, Krzysztof Kozlowski, Conor Dooley, Shawn Guo,
Sascha Hauer, Pengutronix Kernel Team, Fabio Estevam,
NXP Linux Team
Cc: patchwork-jzi, devicetree, linux-arm-kernel, linux-kernel, Johannes Zink
The i.MX8MP Reference Manual rev 1 06/2021, section 11.7.2.5 "Timestamp
Support" indicates the PTP timestamp clock expects a typical frequency
of 125MHz.
As this also improves the precision of the measured timestamps: assign
appropriate 125MHz Clock parent. As no one except the timestamping
counter uses this clock, there are no side-effects of this change in
other peripherals.
Signed-off-by: Johannes Zink <j.zink@pengutronix.de>
---
Changes in v2:
- not only set assigned-clock-parents but alkso assigned-clock-rates for
IMX8MP_CLK_ENET_QOS_TIMER to 125MHz (found by Fabio's review -
thanks!)
- Link to v1: https://lore.kernel.org/r/20230719-imx8mp_enet_qos_use_125mhz_clock-v1-1-782c9ac6e121@pengutronix.de
---
Changes:
v1 -> v2: Worked in Fabio's Feedback - Thank you for your review!
- not only set assigned clock parent to 125MHz but also
set the assigned clock rate of IMX8MP_CLK_ENET_QOS_TIMER
to 125MHz
---
arch/arm64/boot/dts/freescale/imx8mp.dtsi | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
index 6f2f50e1639c..84ecf07affb3 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
@@ -1334,9 +1334,9 @@ eqos: ethernet@30bf0000 {
<&clk IMX8MP_CLK_ENET_QOS_TIMER>,
<&clk IMX8MP_CLK_ENET_QOS>;
assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_266M>,
- <&clk IMX8MP_SYS_PLL2_100M>,
+ <&clk IMX8MP_SYS_PLL2_125M>,
<&clk IMX8MP_SYS_PLL2_125M>;
- assigned-clock-rates = <0>, <100000000>, <125000000>;
+ assigned-clock-rates = <0>, <125000000>, <125000000>;
nvmem-cells = <ð_mac2>;
nvmem-cell-names = "mac-address";
intf_mode = <&gpr 0x4>;
---
base-commit: ba345b77fae7054d0cbd033283c47033e45db6d8
change-id: 20230719-imx8mp_enet_qos_use_125mhz_clock-1c4611c979ba
Best regards,
--
Johannes Zink <j.zink@pengutronix.de>
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v2] arm64: dts: imx8mp: use correct clock for eqos timestamping counter
@ 2023-07-21 3:51 ` Johannes Zink
0 siblings, 0 replies; 5+ messages in thread
From: Johannes Zink @ 2023-07-21 3:51 UTC (permalink / raw)
To: Rob Herring, Krzysztof Kozlowski, Conor Dooley, Shawn Guo,
Sascha Hauer, Pengutronix Kernel Team, Fabio Estevam,
NXP Linux Team
Cc: patchwork-jzi, devicetree, linux-arm-kernel, linux-kernel, Johannes Zink
The i.MX8MP Reference Manual rev 1 06/2021, section 11.7.2.5 "Timestamp
Support" indicates the PTP timestamp clock expects a typical frequency
of 125MHz.
As this also improves the precision of the measured timestamps: assign
appropriate 125MHz Clock parent. As no one except the timestamping
counter uses this clock, there are no side-effects of this change in
other peripherals.
Signed-off-by: Johannes Zink <j.zink@pengutronix.de>
---
Changes in v2:
- not only set assigned-clock-parents but alkso assigned-clock-rates for
IMX8MP_CLK_ENET_QOS_TIMER to 125MHz (found by Fabio's review -
thanks!)
- Link to v1: https://lore.kernel.org/r/20230719-imx8mp_enet_qos_use_125mhz_clock-v1-1-782c9ac6e121@pengutronix.de
---
Changes:
v1 -> v2: Worked in Fabio's Feedback - Thank you for your review!
- not only set assigned clock parent to 125MHz but also
set the assigned clock rate of IMX8MP_CLK_ENET_QOS_TIMER
to 125MHz
---
arch/arm64/boot/dts/freescale/imx8mp.dtsi | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
index 6f2f50e1639c..84ecf07affb3 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
@@ -1334,9 +1334,9 @@ eqos: ethernet@30bf0000 {
<&clk IMX8MP_CLK_ENET_QOS_TIMER>,
<&clk IMX8MP_CLK_ENET_QOS>;
assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_266M>,
- <&clk IMX8MP_SYS_PLL2_100M>,
+ <&clk IMX8MP_SYS_PLL2_125M>,
<&clk IMX8MP_SYS_PLL2_125M>;
- assigned-clock-rates = <0>, <100000000>, <125000000>;
+ assigned-clock-rates = <0>, <125000000>, <125000000>;
nvmem-cells = <ð_mac2>;
nvmem-cell-names = "mac-address";
intf_mode = <&gpr 0x4>;
---
base-commit: ba345b77fae7054d0cbd033283c47033e45db6d8
change-id: 20230719-imx8mp_enet_qos_use_125mhz_clock-1c4611c979ba
Best regards,
--
Johannes Zink <j.zink@pengutronix.de>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v2] arm64: dts: imx8mp: use correct clock for eqos timestamping counter
2023-07-21 3:51 ` Johannes Zink
@ 2023-07-22 1:49 ` Fabio Estevam
-1 siblings, 0 replies; 5+ messages in thread
From: Fabio Estevam @ 2023-07-22 1:49 UTC (permalink / raw)
To: Johannes Zink
Cc: Rob Herring, Krzysztof Kozlowski, Conor Dooley, Shawn Guo,
Sascha Hauer, Pengutronix Kernel Team, NXP Linux Team,
patchwork-jzi, devicetree, linux-arm-kernel, linux-kernel
On Fri, Jul 21, 2023 at 12:51 AM Johannes Zink <j.zink@pengutronix.de> wrote:
>
> The i.MX8MP Reference Manual rev 1 06/2021, section 11.7.2.5 "Timestamp
> Support" indicates the PTP timestamp clock expects a typical frequency
> of 125MHz.
>
> As this also improves the precision of the measured timestamps: assign
> appropriate 125MHz Clock parent. As no one except the timestamping
> counter uses this clock, there are no side-effects of this change in
> other peripherals.
>
> Signed-off-by: Johannes Zink <j.zink@pengutronix.de>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] arm64: dts: imx8mp: use correct clock for eqos timestamping counter
@ 2023-07-22 1:49 ` Fabio Estevam
0 siblings, 0 replies; 5+ messages in thread
From: Fabio Estevam @ 2023-07-22 1:49 UTC (permalink / raw)
To: Johannes Zink
Cc: Rob Herring, Krzysztof Kozlowski, Conor Dooley, Shawn Guo,
Sascha Hauer, Pengutronix Kernel Team, NXP Linux Team,
patchwork-jzi, devicetree, linux-arm-kernel, linux-kernel
On Fri, Jul 21, 2023 at 12:51 AM Johannes Zink <j.zink@pengutronix.de> wrote:
>
> The i.MX8MP Reference Manual rev 1 06/2021, section 11.7.2.5 "Timestamp
> Support" indicates the PTP timestamp clock expects a typical frequency
> of 125MHz.
>
> As this also improves the precision of the measured timestamps: assign
> appropriate 125MHz Clock parent. As no one except the timestamping
> counter uses this clock, there are no side-effects of this change in
> other peripherals.
>
> Signed-off-by: Johannes Zink <j.zink@pengutronix.de>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] arm64: dts: imx8mp: use correct clock for eqos timestamping counter
2023-07-22 1:49 ` Fabio Estevam
(?)
@ 2023-07-24 12:42 ` Johannes Zink
-1 siblings, 0 replies; 5+ messages in thread
From: Johannes Zink @ 2023-07-24 12:42 UTC (permalink / raw)
To: Fabio Estevam
Cc: devicetree, Conor Dooley, Krzysztof Kozlowski, Sascha Hauer,
linux-kernel, Rob Herring, NXP Linux Team,
Pengutronix Kernel Team, Shawn Guo, linux-arm-kernel,
patchwork-jzi
Hi everyone,
On 7/22/23 03:49, Fabio Estevam wrote:
> On Fri, Jul 21, 2023 at 12:51 AM Johannes Zink <j.zink@pengutronix.de> wrote:
>>
>> The i.MX8MP Reference Manual rev 1 06/2021, section 11.7.2.5 "Timestamp
>> Support" indicates the PTP timestamp clock expects a typical frequency
>> of 125MHz.
>>
>> As this also improves the precision of the measured timestamps: assign
>> appropriate 125MHz Clock parent. As no one except the timestamping
>> counter uses this clock, there are no side-effects of this change in
>> other peripherals.
>>
>> Signed-off-by: Johannes Zink <j.zink@pengutronix.de>
>
> Reviewed-by: Fabio Estevam <festevam@gmail.com>
>
>
please scratch this patch, the PTP Timestamping clock cannot be supplied with a
125MHz clock, there is no 125MHz source in the MUX input and I misinterpreted
the clocksummary when testing this patch.
Sorry for the noise,
Johannes
--
Pengutronix e.K. | Johannes Zink |
Steuerwalder Str. 21 | https://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686| Fax: +49-5121-206917-5555 |
^ permalink raw reply [flat|nested] 5+ messages in thread
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2023-07-21 3:51 [PATCH v2] arm64: dts: imx8mp: use correct clock for eqos timestamping counter Johannes Zink
2023-07-21 3:51 ` Johannes Zink
2023-07-22 1:49 ` Fabio Estevam
2023-07-22 1:49 ` Fabio Estevam
2023-07-24 12:42 ` Johannes Zink
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