On 13:54-20240326, Andrew Davis wrote:
> As described in the binding document for the "current-speed" property:
>
> "This should only be present in case a driver has no chance to know the
> baud rate of the slave device."
>
> This is not the case for the UART used in K3 devices, the current
> baud-rate can be calculated from the registers. Having this property
I do not understand the explanation above -> how does one do this?
If you are talking of the 8250 divider registers, someone has to program
those - how do you compute the baud rate from registers that aren't
programmed? Note: I am not commenting on the rationale of removing the
property, just trying to understand the assertion above.
> has the effect of actually skipping the baud-rate setup in some drivers
> as it assumes it will already be set to this rate, which may not always
> be the case.
>
> It seems this property's purpose was mistaken as selecting the desired
> baud-rate, which it does not. It would have been wrong to select that
> here anyway as DT is not the place for configuration, especially when
> there are already more standard ways to set serial baud-rates.
>
> Signed-off-by: Andrew Davis <afd@xxxxxx>
> ---
> arch/arm64/boot/dts/ti/k3-am65-main.dtsi | 1 -
> arch/arm64/boot/dts/ti/k3-am65-mcu.dtsi | 1 -
> arch/arm64/boot/dts/ti/k3-am65-wakeup.dtsi | 1 -
> 3 files changed, 3 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
> index ff857117d7193..670557c89f756 100644
> --- a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
> @@ -89,7 +89,6 @@ main_uart0: serial@2800000 {
> reg = <0x00 0x02800000 0x00 0x100>;
> interrupts = <GIC_SPI 192 IRQ_TYPE_LEVEL_HIGH>;
> clock-frequency = <48000000>;
> - current-speed = <115200>;
> power-domains = <&k3_pds 146 TI_SCI_PD_EXCLUSIVE>;
> status = "disabled";
> };
> diff --git a/arch/arm64/boot/dts/ti/k3-am65-mcu.dtsi b/arch/arm64/boot/dts/ti/k3-am65-mcu.dtsi
> index 6ff3ccc39fb44..4f808e5089755 100644
> --- a/arch/arm64/boot/dts/ti/k3-am65-mcu.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-am65-mcu.dtsi
> @@ -43,7 +43,6 @@ mcu_uart0: serial@40a00000 {
> reg = <0x00 0x40a00000 0x00 0x100>;
> interrupts = <GIC_SPI 565 IRQ_TYPE_LEVEL_HIGH>;
> clock-frequency = <96000000>;
> - current-speed = <115200>;
> power-domains = <&k3_pds 149 TI_SCI_PD_EXCLUSIVE>;
> status = "disabled";
> };
> diff --git a/arch/arm64/boot/dts/ti/k3-am65-wakeup.dtsi b/arch/arm64/boot/dts/ti/k3-am65-wakeup.dtsi
> index 37527890ddeaf..eee072e44a42f 100644
> --- a/arch/arm64/boot/dts/ti/k3-am65-wakeup.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-am65-wakeup.dtsi
> @@ -59,7 +59,6 @@ wkup_uart0: serial@42300000 {
> reg = <0x42300000 0x100>;
> interrupts = <GIC_SPI 697 IRQ_TYPE_LEVEL_HIGH>;
> clock-frequency = <48000000>;
> - current-speed = <115200>;
> power-domains = <&k3_pds 150 TI_SCI_PD_EXCLUSIVE>;
> status = "disabled";
> };
> --
> 2.39.2
>
--
Regards,
Nishanth Menon
Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3 1A34 DDB5 849D 1736 249D
