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[PATCH v3 3/3] arm64: dts: meson-g12-common: Use the G12A UART compatible string

Martin Blumenstingl posted 3 patches 2 years, 6 months ago
[PATCH v3 3/3] arm64: dts: meson-g12-common: Use the G12A UART compatible string
Posted by Martin Blumenstingl 2 years, 6 months ago 
Switch meson-12-common.dtsi to use the Meson G12A specific UART
compatible string. This enables the "divide XTAL by 2" divider which
improves support for UART attached Bluetooth modules (for example
RTL8822CS) running at a baud rate of 1500000. Without dividing XTAL
(24MHz) by 2 a baud rate of 1500000 cannot be generated cleanly and the
resulting jitter breaks communication with the module.

Tested-by: Christian Hewitt <christianshewitt@gmail.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
Greg, please don't take this through your tree. I included this patch
to show the overall goal of this series. If Neil won't take this as
part of another series then I'll send it separately.

Changes from v1 -> v2:
- keep meson-gx-uart as fallback compatible string

Changes from v2 -> v3:
- none


 arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
index 123a56f7f818..904bcd4d2acf 100644
--- a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
@@ -2046,7 +2046,8 @@ pwm_AO_cd: pwm@2000 {
 			};
 
 			uart_AO: serial@3000 {
-				compatible = "amlogic,meson-gx-uart",
+				compatible = "amlogic,meson-g12a-uart",
+					     "amlogic,meson-gx-uart",
 					     "amlogic,meson-ao-uart";
 				reg = <0x0 0x3000 0x0 0x18>;
 				interrupts = <GIC_SPI 193 IRQ_TYPE_EDGE_RISING>;
@@ -2056,7 +2057,8 @@ uart_AO: serial@3000 {
 			};
 
 			uart_AO_B: serial@4000 {
-				compatible = "amlogic,meson-gx-uart",
+				compatible = "amlogic,meson-g12a-uart",
+					     "amlogic,meson-gx-uart",
 					     "amlogic,meson-ao-uart";
 				reg = <0x0 0x4000 0x0 0x18>;
 				interrupts = <GIC_SPI 197 IRQ_TYPE_EDGE_RISING>;
@@ -2293,7 +2295,8 @@ clk_msr: clock-measure@18000 {
 			};
 
 			uart_C: serial@22000 {
-				compatible = "amlogic,meson-gx-uart";
+				compatible = "amlogic,meson-g12a-uart",
+					     "amlogic,meson-gx-uart";
 				reg = <0x0 0x22000 0x0 0x18>;
 				interrupts = <GIC_SPI 93 IRQ_TYPE_EDGE_RISING>;
 				clocks = <&xtal>, <&clkc CLKID_UART2>, <&xtal>;
@@ -2302,7 +2305,8 @@ uart_C: serial@22000 {
 			};
 
 			uart_B: serial@23000 {
-				compatible = "amlogic,meson-gx-uart";
+				compatible = "amlogic,meson-g12a-uart",
+					     "amlogic,meson-gx-uart";
 				reg = <0x0 0x23000 0x0 0x18>;
 				interrupts = <GIC_SPI 75 IRQ_TYPE_EDGE_RISING>;
 				clocks = <&xtal>, <&clkc CLKID_UART1>, <&xtal>;
@@ -2311,7 +2315,8 @@ uart_B: serial@23000 {
 			};
 
 			uart_A: serial@24000 {
-				compatible = "amlogic,meson-gx-uart";
+				compatible = "amlogic,meson-g12a-uart",
+					     "amlogic,meson-gx-uart";
 				reg = <0x0 0x24000 0x0 0x18>;
 				interrupts = <GIC_SPI 26 IRQ_TYPE_EDGE_RISING>;
 				clocks = <&xtal>, <&clkc CLKID_UART0>, <&xtal>;
-- 
2.39.2
Re: [PATCH v3 3/3] arm64: dts: meson-g12-common: Use the G12A UART compatible string
Posted by neil.armstrong@linaro.org 2 years, 6 months ago 
On 07/03/2023 23:26, Martin Blumenstingl wrote:
> Switch meson-12-common.dtsi to use the Meson G12A specific UART
> compatible string. This enables the "divide XTAL by 2" divider which
> improves support for UART attached Bluetooth modules (for example
> RTL8822CS) running at a baud rate of 1500000. Without dividing XTAL
> (24MHz) by 2 a baud rate of 1500000 cannot be generated cleanly and the
> resulting jitter breaks communication with the module.
> 
> Tested-by: Christian Hewitt <christianshewitt@gmail.com>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
> Greg, please don't take this through your tree. I included this patch
> to show the overall goal of this series. If Neil won't take this as
> part of another series then I'll send it separately.

Actually I'm ok if Greg takes the whole patchset, including this one, via
the tty tree.

Neil

> 
> Changes from v1 -> v2:
> - keep meson-gx-uart as fallback compatible string
> 
> Changes from v2 -> v3:
> - none
> 
> 
>   arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi | 15 ++++++++++-----
>   1 file changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
> index 123a56f7f818..904bcd4d2acf 100644
> --- a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
> +++ b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
> @@ -2046,7 +2046,8 @@ pwm_AO_cd: pwm@2000 {
>   			};
>   
>   			uart_AO: serial@3000 {
> -				compatible = "amlogic,meson-gx-uart",
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart",
>   					     "amlogic,meson-ao-uart";
>   				reg = <0x0 0x3000 0x0 0x18>;
>   				interrupts = <GIC_SPI 193 IRQ_TYPE_EDGE_RISING>;
> @@ -2056,7 +2057,8 @@ uart_AO: serial@3000 {
>   			};
>   
>   			uart_AO_B: serial@4000 {
> -				compatible = "amlogic,meson-gx-uart",
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart",
>   					     "amlogic,meson-ao-uart";
>   				reg = <0x0 0x4000 0x0 0x18>;
>   				interrupts = <GIC_SPI 197 IRQ_TYPE_EDGE_RISING>;
> @@ -2293,7 +2295,8 @@ clk_msr: clock-measure@18000 {
>   			};
>   
>   			uart_C: serial@22000 {
> -				compatible = "amlogic,meson-gx-uart";
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart";
>   				reg = <0x0 0x22000 0x0 0x18>;
>   				interrupts = <GIC_SPI 93 IRQ_TYPE_EDGE_RISING>;
>   				clocks = <&xtal>, <&clkc CLKID_UART2>, <&xtal>;
> @@ -2302,7 +2305,8 @@ uart_C: serial@22000 {
>   			};
>   
>   			uart_B: serial@23000 {
> -				compatible = "amlogic,meson-gx-uart";
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart";
>   				reg = <0x0 0x23000 0x0 0x18>;
>   				interrupts = <GIC_SPI 75 IRQ_TYPE_EDGE_RISING>;
>   				clocks = <&xtal>, <&clkc CLKID_UART1>, <&xtal>;
> @@ -2311,7 +2315,8 @@ uart_B: serial@23000 {
>   			};
>   
>   			uart_A: serial@24000 {
> -				compatible = "amlogic,meson-gx-uart";
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart";
>   				reg = <0x0 0x24000 0x0 0x18>;
>   				interrupts = <GIC_SPI 26 IRQ_TYPE_EDGE_RISING>;
>   				clocks = <&xtal>, <&clkc CLKID_UART0>, <&xtal>;
Re: [PATCH v3 3/3] arm64: dts: meson-g12-common: Use the G12A UART compatible string
Posted by Greg KH 2 years, 6 months ago 
On Wed, Mar 08, 2023 at 01:21:21PM +0100, neil.armstrong@linaro.org wrote:
> On 07/03/2023 23:26, Martin Blumenstingl wrote:
> > Switch meson-12-common.dtsi to use the Meson G12A specific UART
> > compatible string. This enables the "divide XTAL by 2" divider which
> > improves support for UART attached Bluetooth modules (for example
> > RTL8822CS) running at a baud rate of 1500000. Without dividing XTAL
> > (24MHz) by 2 a baud rate of 1500000 cannot be generated cleanly and the
> > resulting jitter breaks communication with the module.
> > 
> > Tested-by: Christian Hewitt <christianshewitt@gmail.com>
> > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> > ---
> > Greg, please don't take this through your tree. I included this patch
> > to show the overall goal of this series. If Neil won't take this as
> > part of another series then I'll send it separately.
> 
> Actually I'm ok if Greg takes the whole patchset, including this one, via
> the tty tree.

Ok, I'll take them all, thanks.

greg k-h
Re: [PATCH v3 3/3] arm64: dts: meson-g12-common: Use the G12A UART compatible string
Posted by neil.armstrong@linaro.org 2 years, 6 months ago 
On 07/03/2023 23:26, Martin Blumenstingl wrote:
> Switch meson-12-common.dtsi to use the Meson G12A specific UART
> compatible string. This enables the "divide XTAL by 2" divider which
> improves support for UART attached Bluetooth modules (for example
> RTL8822CS) running at a baud rate of 1500000. Without dividing XTAL
> (24MHz) by 2 a baud rate of 1500000 cannot be generated cleanly and the
> resulting jitter breaks communication with the module.
> 
> Tested-by: Christian Hewitt <christianshewitt@gmail.com>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
> Greg, please don't take this through your tree. I included this patch
> to show the overall goal of this series. If Neil won't take this as
> part of another series then I'll send it separately.
> 
> Changes from v1 -> v2:
> - keep meson-gx-uart as fallback compatible string
> 
> Changes from v2 -> v3:
> - none
> 
> 
>   arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi | 15 ++++++++++-----
>   1 file changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
> index 123a56f7f818..904bcd4d2acf 100644
> --- a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
> +++ b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
> @@ -2046,7 +2046,8 @@ pwm_AO_cd: pwm@2000 {
>   			};
>   
>   			uart_AO: serial@3000 {
> -				compatible = "amlogic,meson-gx-uart",
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart",
>   					     "amlogic,meson-ao-uart";
>   				reg = <0x0 0x3000 0x0 0x18>;
>   				interrupts = <GIC_SPI 193 IRQ_TYPE_EDGE_RISING>;
> @@ -2056,7 +2057,8 @@ uart_AO: serial@3000 {
>   			};
>   
>   			uart_AO_B: serial@4000 {
> -				compatible = "amlogic,meson-gx-uart",
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart",
>   					     "amlogic,meson-ao-uart";
>   				reg = <0x0 0x4000 0x0 0x18>;
>   				interrupts = <GIC_SPI 197 IRQ_TYPE_EDGE_RISING>;
> @@ -2293,7 +2295,8 @@ clk_msr: clock-measure@18000 {
>   			};
>   
>   			uart_C: serial@22000 {
> -				compatible = "amlogic,meson-gx-uart";
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart";
>   				reg = <0x0 0x22000 0x0 0x18>;
>   				interrupts = <GIC_SPI 93 IRQ_TYPE_EDGE_RISING>;
>   				clocks = <&xtal>, <&clkc CLKID_UART2>, <&xtal>;
> @@ -2302,7 +2305,8 @@ uart_C: serial@22000 {
>   			};
>   
>   			uart_B: serial@23000 {
> -				compatible = "amlogic,meson-gx-uart";
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart";
>   				reg = <0x0 0x23000 0x0 0x18>;
>   				interrupts = <GIC_SPI 75 IRQ_TYPE_EDGE_RISING>;
>   				clocks = <&xtal>, <&clkc CLKID_UART1>, <&xtal>;
> @@ -2311,7 +2315,8 @@ uart_B: serial@23000 {
>   			};
>   
>   			uart_A: serial@24000 {
> -				compatible = "amlogic,meson-gx-uart";
> +				compatible = "amlogic,meson-g12a-uart",
> +					     "amlogic,meson-gx-uart";
>   				reg = <0x0 0x24000 0x0 0x18>;
>   				interrupts = <GIC_SPI 26 IRQ_TYPE_EDGE_RISING>;
>   				clocks = <&xtal>, <&clkc CLKID_UART0>, <&xtal>;

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

Patchew 2.1-devel-b67e4c2

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