* [PATCH v2 0/3] meson-uart: Use "divide XTAL by 2" bit on G12A
@ 2023-03-06 19:42 ` Martin Blumenstingl
0 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt,
Martin Blumenstingl
This series improves support for UART attached Bluetooth modules on
Amlogic Meson G12A and newer SoCs. These SoCs also support the "divide
XTAL by 2" bit which (greatly) reduces jitter when generating baud
rates such as 1500000 (which is used by the Bluetooth part of the
RTL8822CS SDIO WiFi and UART Bluetooth combo chip).
Without this the baud rate calculation is based on the XTAL clock
(running at 24MHz) divided by 3 (meaning: 8MHz). 8MHz cannot be divided
with integer division to a 1500000 baud rate. Using the "divide XTAL
by 2" bit however means that we can achieve 1500000 cleanly, without any
jitter.
In future we should allow dynamic switching of these UART controller
internal dividers to pick the best divider automatically for the
requested baud rate. This however still requires the new compatible
string - which is added by this series - to enable the "divide XTAL
by 2" logic on SoCs that support it (G12A and newer).
Changes since v1 at [1]:
- make meson-gx-uart a valid fallback compatible string for the newer
meson-g12a-uart
- rebased on top of v6.3-rc1
[0] https://lore.kernel.org/linux-bluetooth/3B9D4DB2-D2CD-44FE-817A-F6EA8A0AD734@gmail.com/
[1] https://lore.kernel.org/lkml/20230222210425.626474-1-martin.blumenstingl@googlemail.com/
Martin Blumenstingl (3):
dt-bindings: serial: amlogic,meson-uart: Add compatible string for
G12A
tty: serial: meson: Add a new compatible string for the G12A SoC
arm64: dts: meson-g12-common: Use the G12A UART compatible string
.../bindings/serial/amlogic,meson-uart.yaml | 28 +++++++++++++------
.../boot/dts/amlogic/meson-g12-common.dtsi | 15 ++++++----
drivers/tty/serial/meson_uart.c | 8 ++++--
3 files changed, 35 insertions(+), 16 deletions(-)
--
2.39.2
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH v2 0/3] meson-uart: Use "divide XTAL by 2" bit on G12A
@ 2023-03-06 19:42 ` Martin Blumenstingl
0 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: neil.armstrong, Martin Blumenstingl, gregkh, linux-kernel,
robh+dt, krzysztof.kozlowski+dt, jirislaby, linux-arm-kernel
This series improves support for UART attached Bluetooth modules on
Amlogic Meson G12A and newer SoCs. These SoCs also support the "divide
XTAL by 2" bit which (greatly) reduces jitter when generating baud
rates such as 1500000 (which is used by the Bluetooth part of the
RTL8822CS SDIO WiFi and UART Bluetooth combo chip).
Without this the baud rate calculation is based on the XTAL clock
(running at 24MHz) divided by 3 (meaning: 8MHz). 8MHz cannot be divided
with integer division to a 1500000 baud rate. Using the "divide XTAL
by 2" bit however means that we can achieve 1500000 cleanly, without any
jitter.
In future we should allow dynamic switching of these UART controller
internal dividers to pick the best divider automatically for the
requested baud rate. This however still requires the new compatible
string - which is added by this series - to enable the "divide XTAL
by 2" logic on SoCs that support it (G12A and newer).
Changes since v1 at [1]:
- make meson-gx-uart a valid fallback compatible string for the newer
meson-g12a-uart
- rebased on top of v6.3-rc1
[0] https://lore.kernel.org/linux-bluetooth/3B9D4DB2-D2CD-44FE-817A-F6EA8A0AD734@gmail.com/
[1] https://lore.kernel.org/lkml/20230222210425.626474-1-martin.blumenstingl@googlemail.com/
Martin Blumenstingl (3):
dt-bindings: serial: amlogic,meson-uart: Add compatible string for
G12A
tty: serial: meson: Add a new compatible string for the G12A SoC
arm64: dts: meson-g12-common: Use the G12A UART compatible string
.../bindings/serial/amlogic,meson-uart.yaml | 28 +++++++++++++------
.../boot/dts/amlogic/meson-g12-common.dtsi | 15 ++++++----
drivers/tty/serial/meson_uart.c | 8 ++++--
3 files changed, 35 insertions(+), 16 deletions(-)
--
2.39.2
_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH v2 0/3] meson-uart: Use "divide XTAL by 2" bit on G12A
@ 2023-03-06 19:42 ` Martin Blumenstingl
0 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt,
Martin Blumenstingl
This series improves support for UART attached Bluetooth modules on
Amlogic Meson G12A and newer SoCs. These SoCs also support the "divide
XTAL by 2" bit which (greatly) reduces jitter when generating baud
rates such as 1500000 (which is used by the Bluetooth part of the
RTL8822CS SDIO WiFi and UART Bluetooth combo chip).
Without this the baud rate calculation is based on the XTAL clock
(running at 24MHz) divided by 3 (meaning: 8MHz). 8MHz cannot be divided
with integer division to a 1500000 baud rate. Using the "divide XTAL
by 2" bit however means that we can achieve 1500000 cleanly, without any
jitter.
In future we should allow dynamic switching of these UART controller
internal dividers to pick the best divider automatically for the
requested baud rate. This however still requires the new compatible
string - which is added by this series - to enable the "divide XTAL
by 2" logic on SoCs that support it (G12A and newer).
Changes since v1 at [1]:
- make meson-gx-uart a valid fallback compatible string for the newer
meson-g12a-uart
- rebased on top of v6.3-rc1
[0] https://lore.kernel.org/linux-bluetooth/3B9D4DB2-D2CD-44FE-817A-F6EA8A0AD734@gmail.com/
[1] https://lore.kernel.org/lkml/20230222210425.626474-1-martin.blumenstingl@googlemail.com/
Martin Blumenstingl (3):
dt-bindings: serial: amlogic,meson-uart: Add compatible string for
G12A
tty: serial: meson: Add a new compatible string for the G12A SoC
arm64: dts: meson-g12-common: Use the G12A UART compatible string
.../bindings/serial/amlogic,meson-uart.yaml | 28 +++++++++++++------
.../boot/dts/amlogic/meson-g12-common.dtsi | 15 ++++++----
drivers/tty/serial/meson_uart.c | 8 ++++--
3 files changed, 35 insertions(+), 16 deletions(-)
--
2.39.2
_______________________________________________
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] 15+ messages in thread
* [PATCH v2 1/3] dt-bindings: serial: amlogic,meson-uart: Add compatible string for G12A
2023-03-06 19:42 ` Martin Blumenstingl
(?)
@ 2023-03-06 19:42 ` Martin Blumenstingl
-1 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt,
Martin Blumenstingl
Amlogic G12A SoCs gained a new "divide XTAL by 2" bit. Everything else
(we know about) is identical to the UART IP on GX (GXBB/GXL/GXM) SoCs.
Add a new compatible string for this SoC so this new bit can be managed
accordingly while keeping "amlogic,meson-gx-uart" as fallback compatible
string.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
Changes from v1 -> v2:
- make meson-gx-uart a valid compatible string for meson-g12a-uart
.../bindings/serial/amlogic,meson-uart.yaml | 28 +++++++++++++------
1 file changed, 19 insertions(+), 9 deletions(-)
diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
index 3cbdde85ed71..f3af0da8edaf 100644
--- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
+++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
@@ -26,21 +26,31 @@ properties:
compatible:
oneOf:
- description: Always-on power domain UART controller
- items:
+ oneOf:
+ - items:
+ - enum:
+ - amlogic,meson6-uart
+ - amlogic,meson8-uart
+ - amlogic,meson8b-uart
+ - amlogic,meson-gx-uart
+ - amlogic,meson-s4-uart
+ - const: amlogic,meson-ao-uart
+ - items:
+ - const: amlogic,meson-g12a-uart
+ - const: amlogic,meson-gx-uart
+ - const: amlogic,meson-ao-uart
+ - description: Everything-Else power domain UART controller
+ oneOf:
- enum:
- amlogic,meson6-uart
- amlogic,meson8-uart
- amlogic,meson8b-uart
- amlogic,meson-gx-uart
+ - amlogic,meson-g12a-uart
- amlogic,meson-s4-uart
- - const: amlogic,meson-ao-uart
- - description: Everything-Else power domain UART controller
- enum:
- - amlogic,meson6-uart
- - amlogic,meson8-uart
- - amlogic,meson8b-uart
- - amlogic,meson-gx-uart
- - amlogic,meson-s4-uart
+ - items:
+ - const: amlogic,meson-g12a-uart
+ - const: amlogic,meson-gx-uart
reg:
maxItems: 1
--
2.39.2
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 1/3] dt-bindings: serial: amlogic,meson-uart: Add compatible string for G12A
@ 2023-03-06 19:42 ` Martin Blumenstingl
0 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: neil.armstrong, Martin Blumenstingl, gregkh, linux-kernel,
robh+dt, krzysztof.kozlowski+dt, jirislaby, linux-arm-kernel
Amlogic G12A SoCs gained a new "divide XTAL by 2" bit. Everything else
(we know about) is identical to the UART IP on GX (GXBB/GXL/GXM) SoCs.
Add a new compatible string for this SoC so this new bit can be managed
accordingly while keeping "amlogic,meson-gx-uart" as fallback compatible
string.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
Changes from v1 -> v2:
- make meson-gx-uart a valid compatible string for meson-g12a-uart
.../bindings/serial/amlogic,meson-uart.yaml | 28 +++++++++++++------
1 file changed, 19 insertions(+), 9 deletions(-)
diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
index 3cbdde85ed71..f3af0da8edaf 100644
--- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
+++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
@@ -26,21 +26,31 @@ properties:
compatible:
oneOf:
- description: Always-on power domain UART controller
- items:
+ oneOf:
+ - items:
+ - enum:
+ - amlogic,meson6-uart
+ - amlogic,meson8-uart
+ - amlogic,meson8b-uart
+ - amlogic,meson-gx-uart
+ - amlogic,meson-s4-uart
+ - const: amlogic,meson-ao-uart
+ - items:
+ - const: amlogic,meson-g12a-uart
+ - const: amlogic,meson-gx-uart
+ - const: amlogic,meson-ao-uart
+ - description: Everything-Else power domain UART controller
+ oneOf:
- enum:
- amlogic,meson6-uart
- amlogic,meson8-uart
- amlogic,meson8b-uart
- amlogic,meson-gx-uart
+ - amlogic,meson-g12a-uart
- amlogic,meson-s4-uart
- - const: amlogic,meson-ao-uart
- - description: Everything-Else power domain UART controller
- enum:
- - amlogic,meson6-uart
- - amlogic,meson8-uart
- - amlogic,meson8b-uart
- - amlogic,meson-gx-uart
- - amlogic,meson-s4-uart
+ - items:
+ - const: amlogic,meson-g12a-uart
+ - const: amlogic,meson-gx-uart
reg:
maxItems: 1
--
2.39.2
_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 1/3] dt-bindings: serial: amlogic,meson-uart: Add compatible string for G12A
@ 2023-03-06 19:42 ` Martin Blumenstingl
0 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt,
Martin Blumenstingl
Amlogic G12A SoCs gained a new "divide XTAL by 2" bit. Everything else
(we know about) is identical to the UART IP on GX (GXBB/GXL/GXM) SoCs.
Add a new compatible string for this SoC so this new bit can be managed
accordingly while keeping "amlogic,meson-gx-uart" as fallback compatible
string.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
Changes from v1 -> v2:
- make meson-gx-uart a valid compatible string for meson-g12a-uart
.../bindings/serial/amlogic,meson-uart.yaml | 28 +++++++++++++------
1 file changed, 19 insertions(+), 9 deletions(-)
diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
index 3cbdde85ed71..f3af0da8edaf 100644
--- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
+++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
@@ -26,21 +26,31 @@ properties:
compatible:
oneOf:
- description: Always-on power domain UART controller
- items:
+ oneOf:
+ - items:
+ - enum:
+ - amlogic,meson6-uart
+ - amlogic,meson8-uart
+ - amlogic,meson8b-uart
+ - amlogic,meson-gx-uart
+ - amlogic,meson-s4-uart
+ - const: amlogic,meson-ao-uart
+ - items:
+ - const: amlogic,meson-g12a-uart
+ - const: amlogic,meson-gx-uart
+ - const: amlogic,meson-ao-uart
+ - description: Everything-Else power domain UART controller
+ oneOf:
- enum:
- amlogic,meson6-uart
- amlogic,meson8-uart
- amlogic,meson8b-uart
- amlogic,meson-gx-uart
+ - amlogic,meson-g12a-uart
- amlogic,meson-s4-uart
- - const: amlogic,meson-ao-uart
- - description: Everything-Else power domain UART controller
- enum:
- - amlogic,meson6-uart
- - amlogic,meson8-uart
- - amlogic,meson8b-uart
- - amlogic,meson-gx-uart
- - amlogic,meson-s4-uart
+ - items:
+ - const: amlogic,meson-g12a-uart
+ - const: amlogic,meson-gx-uart
reg:
maxItems: 1
--
2.39.2
_______________________________________________
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] 15+ messages in thread
* [PATCH v2 2/3] tty: serial: meson: Add a new compatible string for the G12A SoC
2023-03-06 19:42 ` Martin Blumenstingl
(?)
@ 2023-03-06 19:42 ` Martin Blumenstingl
-1 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt,
Martin Blumenstingl
Amlogic Meson G12A (and later) SoCs also have the "divide XTAL by 2" bit
as the S4 UART controllers. Add a new compatible string for these SoCs
and enable the has_xtal_div2 flag for them.
Tested-by: Christian Hewitt <christianshewitt@gmail.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
Changes from v1 -> v2:
- none
drivers/tty/serial/meson_uart.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 74110017988a..2501db5a7aaf 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -779,7 +779,7 @@ static int meson_uart_remove(struct platform_device *pdev)
return 0;
}
-static struct meson_uart_data s4_uart_data = {
+static struct meson_uart_data meson_g12a_uart_data = {
.has_xtal_div2 = true,
};
@@ -788,9 +788,13 @@ static const struct of_device_id meson_uart_dt_match[] = {
{ .compatible = "amlogic,meson8-uart" },
{ .compatible = "amlogic,meson8b-uart" },
{ .compatible = "amlogic,meson-gx-uart" },
+ {
+ .compatible = "amlogic,meson-g12a-uart",
+ .data = (void *)&meson_g12a_uart_data,
+ },
{
.compatible = "amlogic,meson-s4-uart",
- .data = (void *)&s4_uart_data,
+ .data = (void *)&meson_g12a_uart_data,
},
{ /* sentinel */ },
};
--
2.39.2
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 2/3] tty: serial: meson: Add a new compatible string for the G12A SoC
@ 2023-03-06 19:42 ` Martin Blumenstingl
0 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: neil.armstrong, Martin Blumenstingl, gregkh, linux-kernel,
robh+dt, krzysztof.kozlowski+dt, jirislaby, linux-arm-kernel
Amlogic Meson G12A (and later) SoCs also have the "divide XTAL by 2" bit
as the S4 UART controllers. Add a new compatible string for these SoCs
and enable the has_xtal_div2 flag for them.
Tested-by: Christian Hewitt <christianshewitt@gmail.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
Changes from v1 -> v2:
- none
drivers/tty/serial/meson_uart.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 74110017988a..2501db5a7aaf 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -779,7 +779,7 @@ static int meson_uart_remove(struct platform_device *pdev)
return 0;
}
-static struct meson_uart_data s4_uart_data = {
+static struct meson_uart_data meson_g12a_uart_data = {
.has_xtal_div2 = true,
};
@@ -788,9 +788,13 @@ static const struct of_device_id meson_uart_dt_match[] = {
{ .compatible = "amlogic,meson8-uart" },
{ .compatible = "amlogic,meson8b-uart" },
{ .compatible = "amlogic,meson-gx-uart" },
+ {
+ .compatible = "amlogic,meson-g12a-uart",
+ .data = (void *)&meson_g12a_uart_data,
+ },
{
.compatible = "amlogic,meson-s4-uart",
- .data = (void *)&s4_uart_data,
+ .data = (void *)&meson_g12a_uart_data,
},
{ /* sentinel */ },
};
--
2.39.2
_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 2/3] tty: serial: meson: Add a new compatible string for the G12A SoC
@ 2023-03-06 19:42 ` Martin Blumenstingl
0 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt,
Martin Blumenstingl
Amlogic Meson G12A (and later) SoCs also have the "divide XTAL by 2" bit
as the S4 UART controllers. Add a new compatible string for these SoCs
and enable the has_xtal_div2 flag for them.
Tested-by: Christian Hewitt <christianshewitt@gmail.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
Changes from v1 -> v2:
- none
drivers/tty/serial/meson_uart.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 74110017988a..2501db5a7aaf 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -779,7 +779,7 @@ static int meson_uart_remove(struct platform_device *pdev)
return 0;
}
-static struct meson_uart_data s4_uart_data = {
+static struct meson_uart_data meson_g12a_uart_data = {
.has_xtal_div2 = true,
};
@@ -788,9 +788,13 @@ static const struct of_device_id meson_uart_dt_match[] = {
{ .compatible = "amlogic,meson8-uart" },
{ .compatible = "amlogic,meson8b-uart" },
{ .compatible = "amlogic,meson-gx-uart" },
+ {
+ .compatible = "amlogic,meson-g12a-uart",
+ .data = (void *)&meson_g12a_uart_data,
+ },
{
.compatible = "amlogic,meson-s4-uart",
- .data = (void *)&s4_uart_data,
+ .data = (void *)&meson_g12a_uart_data,
},
{ /* sentinel */ },
};
--
2.39.2
_______________________________________________
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] 15+ messages in thread
* [PATCH v2 3/3] arm64: dts: meson-g12-common: Use the G12A UART compatible string
2023-03-06 19:42 ` Martin Blumenstingl
(?)
@ 2023-03-06 19:42 ` Martin Blumenstingl
-1 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt,
Martin Blumenstingl
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
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
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 3/3] arm64: dts: meson-g12-common: Use the G12A UART compatible string
@ 2023-03-06 19:42 ` Martin Blumenstingl
0 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: neil.armstrong, Martin Blumenstingl, gregkh, linux-kernel,
robh+dt, krzysztof.kozlowski+dt, jirislaby, linux-arm-kernel
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
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
_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 3/3] arm64: dts: meson-g12-common: Use the G12A UART compatible string
@ 2023-03-06 19:42 ` Martin Blumenstingl
0 siblings, 0 replies; 15+ messages in thread
From: Martin Blumenstingl @ 2023-03-06 19:42 UTC (permalink / raw
To: linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt,
Martin Blumenstingl
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
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
_______________________________________________
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] 15+ messages in thread
* Re: [PATCH v2 1/3] dt-bindings: serial: amlogic,meson-uart: Add compatible string for G12A
2023-03-06 19:42 ` Martin Blumenstingl
(?)
@ 2023-03-07 8:47 ` Krzysztof Kozlowski
-1 siblings, 0 replies; 15+ messages in thread
From: Krzysztof Kozlowski @ 2023-03-07 8:47 UTC (permalink / raw
To: Martin Blumenstingl, linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt
On 06/03/2023 20:42, Martin Blumenstingl wrote:
> Amlogic G12A SoCs gained a new "divide XTAL by 2" bit. Everything else
> (we know about) is identical to the UART IP on GX (GXBB/GXL/GXM) SoCs.
> Add a new compatible string for this SoC so this new bit can be managed
> accordingly while keeping "amlogic,meson-gx-uart" as fallback compatible
> string.
>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
> Changes from v1 -> v2:
> - make meson-gx-uart a valid compatible string for meson-g12a-uart
>
>
> .../bindings/serial/amlogic,meson-uart.yaml | 28 +++++++++++++------
> 1 file changed, 19 insertions(+), 9 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> index 3cbdde85ed71..f3af0da8edaf 100644
> --- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> +++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> @@ -26,21 +26,31 @@ properties:
> compatible:
> oneOf:
> - description: Always-on power domain UART controller
> - items:
> + oneOf:
> + - items:
> + - enum:
> + - amlogic,meson6-uart
> + - amlogic,meson8-uart
> + - amlogic,meson8b-uart
> + - amlogic,meson-gx-uart
> + - amlogic,meson-s4-uart
> + - const: amlogic,meson-ao-uart
> + - items:
> + - const: amlogic,meson-g12a-uart
> + - const: amlogic,meson-gx-uart
> + - const: amlogic,meson-ao-uart
> + - description: Everything-Else power domain UART controller
> + oneOf:
> - enum:
> - amlogic,meson6-uart
> - amlogic,meson8-uart
> - amlogic,meson8b-uart
> - amlogic,meson-gx-uart
> + - amlogic,meson-g12a-uart
> - amlogic,meson-s4-uart
> - - const: amlogic,meson-ao-uart
> - - description: Everything-Else power domain UART controller
> - enum:
> - - amlogic,meson6-uart
> - - amlogic,meson8-uart
> - - amlogic,meson8b-uart
> - - amlogic,meson-gx-uart
> - - amlogic,meson-s4-uart
> + - items:
> + - const: amlogic,meson-g12a-uart
> + - const: amlogic,meson-gx-uart
Difficult to review... You claim you add only g12a which seems like is
happening there but with some other changes. I see g12a three times and
a lot of reshuffling. I also see multiple oneOf, so something is clearly
wrong. oneOf is only one.
Best regards,
Krzysztof
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v2 1/3] dt-bindings: serial: amlogic,meson-uart: Add compatible string for G12A
@ 2023-03-07 8:47 ` Krzysztof Kozlowski
0 siblings, 0 replies; 15+ messages in thread
From: Krzysztof Kozlowski @ 2023-03-07 8:47 UTC (permalink / raw
To: Martin Blumenstingl, linux-amlogic, devicetree
Cc: neil.armstrong, gregkh, linux-kernel, robh+dt,
krzysztof.kozlowski+dt, jirislaby, linux-arm-kernel
On 06/03/2023 20:42, Martin Blumenstingl wrote:
> Amlogic G12A SoCs gained a new "divide XTAL by 2" bit. Everything else
> (we know about) is identical to the UART IP on GX (GXBB/GXL/GXM) SoCs.
> Add a new compatible string for this SoC so this new bit can be managed
> accordingly while keeping "amlogic,meson-gx-uart" as fallback compatible
> string.
>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
> Changes from v1 -> v2:
> - make meson-gx-uart a valid compatible string for meson-g12a-uart
>
>
> .../bindings/serial/amlogic,meson-uart.yaml | 28 +++++++++++++------
> 1 file changed, 19 insertions(+), 9 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> index 3cbdde85ed71..f3af0da8edaf 100644
> --- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> +++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> @@ -26,21 +26,31 @@ properties:
> compatible:
> oneOf:
> - description: Always-on power domain UART controller
> - items:
> + oneOf:
> + - items:
> + - enum:
> + - amlogic,meson6-uart
> + - amlogic,meson8-uart
> + - amlogic,meson8b-uart
> + - amlogic,meson-gx-uart
> + - amlogic,meson-s4-uart
> + - const: amlogic,meson-ao-uart
> + - items:
> + - const: amlogic,meson-g12a-uart
> + - const: amlogic,meson-gx-uart
> + - const: amlogic,meson-ao-uart
> + - description: Everything-Else power domain UART controller
> + oneOf:
> - enum:
> - amlogic,meson6-uart
> - amlogic,meson8-uart
> - amlogic,meson8b-uart
> - amlogic,meson-gx-uart
> + - amlogic,meson-g12a-uart
> - amlogic,meson-s4-uart
> - - const: amlogic,meson-ao-uart
> - - description: Everything-Else power domain UART controller
> - enum:
> - - amlogic,meson6-uart
> - - amlogic,meson8-uart
> - - amlogic,meson8b-uart
> - - amlogic,meson-gx-uart
> - - amlogic,meson-s4-uart
> + - items:
> + - const: amlogic,meson-g12a-uart
> + - const: amlogic,meson-gx-uart
Difficult to review... You claim you add only g12a which seems like is
happening there but with some other changes. I see g12a three times and
a lot of reshuffling. I also see multiple oneOf, so something is clearly
wrong. oneOf is only one.
Best regards,
Krzysztof
_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v2 1/3] dt-bindings: serial: amlogic,meson-uart: Add compatible string for G12A
@ 2023-03-07 8:47 ` Krzysztof Kozlowski
0 siblings, 0 replies; 15+ messages in thread
From: Krzysztof Kozlowski @ 2023-03-07 8:47 UTC (permalink / raw
To: Martin Blumenstingl, linux-amlogic, devicetree
Cc: linux-kernel, linux-arm-kernel, jirislaby, neil.armstrong,
krzysztof.kozlowski+dt, robh+dt, gregkh, Christian Hewitt
On 06/03/2023 20:42, Martin Blumenstingl wrote:
> Amlogic G12A SoCs gained a new "divide XTAL by 2" bit. Everything else
> (we know about) is identical to the UART IP on GX (GXBB/GXL/GXM) SoCs.
> Add a new compatible string for this SoC so this new bit can be managed
> accordingly while keeping "amlogic,meson-gx-uart" as fallback compatible
> string.
>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
> Changes from v1 -> v2:
> - make meson-gx-uart a valid compatible string for meson-g12a-uart
>
>
> .../bindings/serial/amlogic,meson-uart.yaml | 28 +++++++++++++------
> 1 file changed, 19 insertions(+), 9 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> index 3cbdde85ed71..f3af0da8edaf 100644
> --- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> +++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
> @@ -26,21 +26,31 @@ properties:
> compatible:
> oneOf:
> - description: Always-on power domain UART controller
> - items:
> + oneOf:
> + - items:
> + - enum:
> + - amlogic,meson6-uart
> + - amlogic,meson8-uart
> + - amlogic,meson8b-uart
> + - amlogic,meson-gx-uart
> + - amlogic,meson-s4-uart
> + - const: amlogic,meson-ao-uart
> + - items:
> + - const: amlogic,meson-g12a-uart
> + - const: amlogic,meson-gx-uart
> + - const: amlogic,meson-ao-uart
> + - description: Everything-Else power domain UART controller
> + oneOf:
> - enum:
> - amlogic,meson6-uart
> - amlogic,meson8-uart
> - amlogic,meson8b-uart
> - amlogic,meson-gx-uart
> + - amlogic,meson-g12a-uart
> - amlogic,meson-s4-uart
> - - const: amlogic,meson-ao-uart
> - - description: Everything-Else power domain UART controller
> - enum:
> - - amlogic,meson6-uart
> - - amlogic,meson8-uart
> - - amlogic,meson8b-uart
> - - amlogic,meson-gx-uart
> - - amlogic,meson-s4-uart
> + - items:
> + - const: amlogic,meson-g12a-uart
> + - const: amlogic,meson-gx-uart
Difficult to review... You claim you add only g12a which seems like is
happening there but with some other changes. I see g12a three times and
a lot of reshuffling. I also see multiple oneOf, so something is clearly
wrong. oneOf is only one.
Best regards,
Krzysztof
_______________________________________________
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] 15+ messages in thread
end of thread, other threads:[~2023-03-07 9:46 UTC | newest]
Thread overview: 15+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-03-06 19:42 [PATCH v2 0/3] meson-uart: Use "divide XTAL by 2" bit on G12A Martin Blumenstingl
2023-03-06 19:42 ` Martin Blumenstingl
2023-03-06 19:42 ` Martin Blumenstingl
2023-03-06 19:42 ` [PATCH v2 1/3] dt-bindings: serial: amlogic,meson-uart: Add compatible string for G12A Martin Blumenstingl
2023-03-06 19:42 ` Martin Blumenstingl
2023-03-06 19:42 ` Martin Blumenstingl
2023-03-07 8:47 ` Krzysztof Kozlowski
2023-03-07 8:47 ` Krzysztof Kozlowski
2023-03-07 8:47 ` Krzysztof Kozlowski
2023-03-06 19:42 ` [PATCH v2 2/3] tty: serial: meson: Add a new compatible string for the G12A SoC Martin Blumenstingl
2023-03-06 19:42 ` Martin Blumenstingl
2023-03-06 19:42 ` Martin Blumenstingl
2023-03-06 19:42 ` [PATCH v2 3/3] arm64: dts: meson-g12-common: Use the G12A UART compatible string Martin Blumenstingl
2023-03-06 19:42 ` Martin Blumenstingl
2023-03-06 19:42 ` Martin Blumenstingl
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