Re: [PATCH net-next 1/7] dt-binding: ti: am65x: document common platform time sync cpts module
From: Grygorii Strashko
Date: Tue May 05 2020 - 11:01:25 EST
On 05/05/2020 07:04, Rob Herring wrote:
On Fri, May 01, 2020 at 11:50:05PM +0300, Grygorii Strashko wrote:
Document device tree bindings for TI AM654/J721E SoC The Common Platform
Time Sync (CPTS) module. The CPTS module is used to facilitate host control
of time sync operations. Main features of CPTS module are:
- selection of multiple external clock sources
- 64-bit timestamp mode in ns with ppm and nudge adjustment.
- control of time sync events via interrupt or polling
- hardware timestamp of ext. events (HWx_TS_PUSH)
- periodic generator function outputs (TS_GENFx)
- PPS in combination with timesync router
- Depending on integration it enables compliance with the IEEE 1588-2008
standard for a precision clock synchronization protocol, Ethernet Enhanced
Scheduled Traffic Operations (CPTS_ESTFn) and PCIe Subsystem Precision Time
Measurement (PTM).
Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
---
.../bindings/net/ti,k3-am654-cpsw-nuss.yaml | 7 +
.../bindings/net/ti,k3-am654-cpts.yaml | 152 ++++++++++++++++++
2 files changed, 159 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml
diff --git a/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml b/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml
index 78bf511e2892..0f3fde45e200 100644
--- a/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml
+++ b/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml
@@ -144,6 +144,13 @@ patternProperties:
description:
CPSW MDIO bus.
+ "^cpts$":
ok
Fixed strings go under 'properties'.
+ type: object
+ allOf:
+ - $ref: "ti,am654-cpts.yaml#"
+ description:
+ CPSW Common Platform Time Sync (CPTS) module.
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml b/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml
new file mode 100644
index 000000000000..1b535d41e5c6
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml
@@ -0,0 +1,152 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/ti,am654-cpts.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: The TI AM654x/J721E Common Platform Time Sync (CPTS) module Device Tree Bindings
+
+maintainers:
+ - Grygorii Strashko <grygorii.strashko@xxxxxx>
+ - Sekhar Nori <nsekhar@xxxxxx>
+
+description: |+
+ The TI AM654x/J721E CPTS module is used to facilitate host control of time
+ sync operations.
+ Main features of CPTS module are
+ - selection of multiple external clock sources
+ - Software control of time sync events via interrupt or polling
+ - 64-bit timestamp mode in ns with PPM and nudge adjustment.
+ - hardware timestamp push inputs (HWx_TS_PUSH)
+ - timestamp counter compare output (TS_COMP)
+ - timestamp counter bit output (TS_SYNC)
+ - periodic Generator function outputs (TS_GENFx)
+ - Ethernet Enhanced Scheduled Traffic Operations (CPTS_ESTFn) (TSN)
+ - external hardware timestamp push inputs (HWx_TS_PUSH) timestamping
+
+ Depending on integration it enables compliance with the IEEE 1588-2008
+ standard for a precision clock synchronization protocol, Ethernet Enhanced
+ Scheduled Traffic Operations (CPTS_ESTFn) and PCIe Subsystem Precision Time
+ Measurement (PTM).
+
+ TI AM654x/J721E SoCs has several similar CPTS modules integrated into the
+ different parts of the system which could be synchronized with each other
+ - Main CPTS
+ - MCU CPSW CPTS with IEEE 1588-2008 support
+ - PCIe subsystem CPTS for PTM support
+
+ Depending on CPTS module integration and when CPTS is integral part of
+ another module (MCU CPSW for example) "compatible" and "reg" can
+ be omitted - parent module is fully responsible for CPTS enabling and
+ configuration.
That's fine, but you should still have compatible and reg.
I'll add reg as below. But compatible is an issue, because
k3-am654-cpsw-nuss call of_platform_populate() to create mdio device.
But for CPTS I do not want to create device as k3-am654-cpsw-nuss uses direct
function calls to CPTS.
Will it be correct to switch to of_platform_device_create() instead of
of_platform_populate()?
+
+properties:
+ $nodename:
+ pattern: "^cpts(@.*|-[0-9a-f])*$"
+
+ compatible:
+ oneOf:
+ - const: ti,am65-cpts
+ - const: ti,j721e-cpts
+
+ reg:
+ maxItems: 1
+ description:
+ The physical base address and size of CPTS IO range
Wrong indentation.
+
+ reg-names:
+ items:
+ - const: cpts
Don't really need *-names when there's only one and you haven't picked
very meaningful names.
Could I keep it if you don't mind?
+
+ clocks:
+ description: CPTS reference clock
+
+ clock-names:
+ items:
+ - const: cpts
+
+ interrupts-extended:
Use 'interrupts' here, the tooling will fixup things to allow both.
[...]
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+ cpts@310d0000 {
+ compatible = "ti,am65-cpts";
+ reg = <0x0 0x310d0000 0x0 0x400>;
+ reg-names = "cpts";
+ clocks = <&main_cpts_mux>;
+ clock-names = "cpts";
+ interrupts-extended = <&k3_irq 163 0 IRQ_TYPE_LEVEL_HIGH>;
+ interrupt-names = "cpts";
+ ti,cpts-periodic-outputs = <6>;
+ ti,cpts-ext-ts-inputs = <8>;
+
+ main_cpts_mux: refclk-mux {
+ #clock-cells = <0>;
+ clocks = <&k3_clks 118 5>, <&k3_clks 118 11>,
+ <&k3_clks 157 91>, <&k3_clks 157 77>,
+ <&k3_clks 157 102>, <&k3_clks 157 80>,
+ <&k3_clks 120 3>, <&k3_clks 121 3>;
+ assigned-clocks = <&main_cpts_mux>;
+ assigned-clock-parents = <&k3_clks 118 11>;
+ };
+ };
+ - |
+
+ cpts {
+ clocks = <&k3_clks 18 2>;
+ clock-names = "cpts";
+ interrupts-extended = <&gic500 GIC_SPI 858 IRQ_TYPE_LEVEL_HIGH>;
+ interrupt-names = "cpts";
+ ti,cpts-ext-ts-inputs = <4>;
+ ti,cpts-periodic-outputs = <2>;
How is this example accessed?
I'll move it in .../bindings/net/ti,k3-am654-cpsw-nuss.yaml as below
--- a/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml
+++ b/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml
@@ -143,7 +143,7 @@ patternProperties:
description:
CPSW MDIO bus.
- "^cpts$":
+ "^cpts(@.*|-[0-9a-f])*$":
type: object
allOf:
- $ref: "ti,am654-cpts.yaml#"
@@ -170,6 +170,8 @@ examples:
#include <dt-bindings/pinctrl/k3.h>
#include <dt-bindings/soc/ti,sci_pm_domain.h>
#include <dt-bindings/net/ti-dp83867.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
mcu_cpsw: ethernet@46000000 {
compatible = "ti,am654-cpsw-nuss";
@@ -228,4 +230,14 @@ examples:
ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>;
};
};
+
+ cpts@3d000 {
+ reg = <0x0 0x3d000 0x0 0x400>;
+ clocks = <&k3_clks 18 2>;
+ clock-names = "cpts";
+ interrupts-extended = <&gic500 GIC_SPI 858 IRQ_TYPE_LEVEL_HIGH>;
+ interrupt-names = "cpts";
+ ti,cpts-ext-ts-inputs = <4>;
+ ti,cpts-periodic-outputs = <2>;
+ };
};
diff --git a/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml b/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml
index 1b535d41e5c6..1f7fdbab3191 100644
--- a/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml
+++ b/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml
@@ -140,13 +140,3 @@ examples:
assigned-clock-parents = <&k3_clks 118 11>;
};
};
- - |
-
- cpts {
- clocks = <&k3_clks 18 2>;
- clock-names = "cpts";
- interrupts-extended = <&gic500 GIC_SPI 858 IRQ_TYPE_LEVEL_HIGH>;
- interrupt-names = "cpts";
- ti,cpts-ext-ts-inputs = <4>;
- ti,cpts-periodic-outputs = <2>;
- };
--
Best regards,
grygorii