[PATCH v3 0/7] usb: dwc3: Calculate REFCLKPER et. al. from reference clock

[PATCH v3 0/7] usb: dwc3: Calculate REFCLKPER et. al. from reference clock

[Sean Anderson]

This is a rework of patches 3-5 of [1]. It attempts to correctly program
REFCLKPER and REFCLK_FLADJ based on the reference clock frequency. Since
we no longer need a special property duplicating this configuration,
snps,ref-clock-period-ns is deprecated.

Please test this! Patches 3/4 in this series have the effect of
programming REFCLKPER and REFCLK_FLADJ on boards which already configure
the "ref" clock. I have build tested, but not much else.

[1] https://lore.kernel.org/linux-usb/20220114044230.2677283-1-robert.hancock@calian.com/

Changes in v3:
- Define each variable on its own line
- Rebase onto linux/master
- Update comment to notes some things mentioned during review

Changes in v2:
- Add snps,ref-clock-frequency-hz property for ACPI
- Also program GFLADJ.240MHZDECR
- Document clock members
- Don't program GFLADJ if the version is < 2.50a

Sean Anderson (7):
  dt-bindings: usb: dwc3: Deprecate snps,ref-clock-period-ns
  usb: dwc3: Get clocks individually
  usb: dwc3: Calculate REFCLKPER based on reference clock
  usb: dwc3: Program GFLADJ
  usb: dwc3: Add snps,ref-clock-frequency-hz property for ACPI
  arm64: dts: zynqmp: Move USB clocks to dwc3 node
  arm64: dts: ipq6018: Use reference clock to set dwc3 period

 .../devicetree/bindings/usb/snps,dwc3.yaml    |   7 +-
 arch/arm64/boot/dts/qcom/ipq6018.dtsi         |   3 +-
 .../arm64/boot/dts/xilinx/zynqmp-clk-ccf.dtsi |   4 +-
 arch/arm64/boot/dts/xilinx/zynqmp.dtsi        |   4 +-
 drivers/usb/dwc3/core.c                       | 117 +++++++++++++++---
 drivers/usb/dwc3/core.h                       |  17 ++-
 6 files changed, 125 insertions(+), 27 deletions(-)

-- 
2.25.1

[PATCH v3 1/7] dt-bindings: usb: dwc3: Deprecate snps,ref-clock-period-ns

[Sean Anderson]

This property is redundant because we can determine the correct value for
REFCLKPER based on the "ref" clock. Deprecate it, and encourage users to
provide a clock instead. This also restricts the minimum and maximum to the
values documented in the register reference [1].

[1] https://www.xilinx.com/html_docs/registers/ug1087/usb3_xhci___guctl.html

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
---

(no changes since v1)

 Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
index d29ffcd27472..4f2b0913ad9f 100644
--- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
+++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
@@ -263,8 +263,11 @@ properties:
       Value for REFCLKPER field of GUCTL register for reference clock period in
       nanoseconds, when the hardware set default does not match the actual
       clock.
-    minimum: 1
-    maximum: 0x3ff
+
+      This binding is deprecated. Instead, provide an appropriate reference clock.
+    minimum: 8
+    maximum: 62
+    deprecated: true
 
   snps,rx-thr-num-pkt-prd:
     description:
-- 
2.25.1

Re: [PATCH v3 1/7] dt-bindings: usb: dwc3: Deprecate snps,ref-clock-period-ns

[Rob Herring]

On Thu, 27 Jan 2022 15:06:30 -0500, Sean Anderson wrote:
> This property is redundant because we can determine the correct value for
> REFCLKPER based on the "ref" clock. Deprecate it, and encourage users to
> provide a clock instead. This also restricts the minimum and maximum to the
> values documented in the register reference [1].
> 
> [1] https://www.xilinx.com/html_docs/registers/ug1087/usb3_xhci___guctl.html
> 
> Signed-off-by: Sean Anderson <sean.anderson@seco.com>
> ---
> 
> (no changes since v1)
> 
>  Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

[PATCH v3 6/7] arm64: dts: zynqmp: Move USB clocks to dwc3 node

[Sean Anderson]

These clocks are not used by the dwc3-xilinx driver except to
enable/disable them. Move them to the dwc3 node so its driver can use
them to configure the reference clock period.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Reviewed-by: Robert Hancock <robert.hancock@calian.com>
Tested-by: Robert Hancock <robert.hancock@calian.com>
---

(no changes since v1)

 arch/arm64/boot/dts/xilinx/zynqmp-clk-ccf.dtsi | 4 ++--
 arch/arm64/boot/dts/xilinx/zynqmp.dtsi         | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/boot/dts/xilinx/zynqmp-clk-ccf.dtsi b/arch/arm64/boot/dts/xilinx/zynqmp-clk-ccf.dtsi
index 1e0b1bca7c94..8493dd7d5f1f 100644
--- a/arch/arm64/boot/dts/xilinx/zynqmp-clk-ccf.dtsi
+++ b/arch/arm64/boot/dts/xilinx/zynqmp-clk-ccf.dtsi
@@ -223,11 +223,11 @@ &uart1 {
 	clocks = <&zynqmp_clk UART1_REF>, <&zynqmp_clk LPD_LSBUS>;
 };
 
-&usb0 {
+&dwc3_0 {
 	clocks = <&zynqmp_clk USB0_BUS_REF>, <&zynqmp_clk USB3_DUAL_REF>;
 };
 
-&usb1 {
+&dwc3_1 {
 	clocks = <&zynqmp_clk USB1_BUS_REF>, <&zynqmp_clk USB3_DUAL_REF>;
 };
 
diff --git a/arch/arm64/boot/dts/xilinx/zynqmp.dtsi b/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
index 74e66443e4ce..ba68fb8529ee 100644
--- a/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
+++ b/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
@@ -811,7 +811,6 @@ usb0: usb@ff9d0000 {
 			status = "disabled";
 			compatible = "xlnx,zynqmp-dwc3";
 			reg = <0x0 0xff9d0000 0x0 0x100>;
-			clock-names = "bus_clk", "ref_clk";
 			power-domains = <&zynqmp_firmware PD_USB_0>;
 			resets = <&zynqmp_reset ZYNQMP_RESET_USB0_CORERESET>,
 				 <&zynqmp_reset ZYNQMP_RESET_USB0_HIBERRESET>,
@@ -825,6 +824,7 @@ dwc3_0: usb@fe200000 {
 				interrupt-parent = <&gic>;
 				interrupt-names = "dwc_usb3", "otg";
 				interrupts = <0 65 4>, <0 69 4>;
+				clock-names = "bus_early", "ref";
 				#stream-id-cells = <1>;
 				iommus = <&smmu 0x860>;
 				snps,quirk-frame-length-adjustment = <0x20>;
@@ -838,7 +838,6 @@ usb1: usb@ff9e0000 {
 			status = "disabled";
 			compatible = "xlnx,zynqmp-dwc3";
 			reg = <0x0 0xff9e0000 0x0 0x100>;
-			clock-names = "bus_clk", "ref_clk";
 			power-domains = <&zynqmp_firmware PD_USB_1>;
 			resets = <&zynqmp_reset ZYNQMP_RESET_USB1_CORERESET>,
 				 <&zynqmp_reset ZYNQMP_RESET_USB1_HIBERRESET>,
@@ -852,6 +851,7 @@ dwc3_1: usb@fe300000 {
 				interrupt-parent = <&gic>;
 				interrupt-names = "dwc_usb3", "otg";
 				interrupts = <0 70 4>, <0 74 4>;
+				clock-names = "bus_early", "ref";
 				#stream-id-cells = <1>;
 				iommus = <&smmu 0x861>;
 				snps,quirk-frame-length-adjustment = <0x20>;
-- 
2.25.1

[PATCH v3 7/7] arm64: dts: ipq6018: Use reference clock to set dwc3 period

[Sean Anderson]

Instead of manually setting snps,ref-clock-period-ns, we can let the
driver calculate it automatically from the "ref" clock. I haven't
reviewed this board's schematics, so please let me know if this is the
wrong 24MHz clock to use.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
---

(no changes since v1)

 arch/arm64/boot/dts/qcom/ipq6018.dtsi | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/ipq6018.dtsi b/arch/arm64/boot/dts/qcom/ipq6018.dtsi
index 66ec5615651d..a614b9f73e2c 100644
--- a/arch/arm64/boot/dts/qcom/ipq6018.dtsi
+++ b/arch/arm64/boot/dts/qcom/ipq6018.dtsi
@@ -743,12 +743,13 @@ dwc_0: usb@8A00000 {
 				interrupts = <GIC_SPI 140 IRQ_TYPE_LEVEL_HIGH>;
 				phys = <&qusb_phy_0>, <&usb0_ssphy>;
 				phy-names = "usb2-phy", "usb3-phy";
+				clocks = <&xo>;
+				clock-names = "ref";
 				tx-fifo-resize;
 				snps,is-utmi-l1-suspend;
 				snps,hird-threshold = /bits/ 8 <0x0>;
 				snps,dis_u2_susphy_quirk;
 				snps,dis_u3_susphy_quirk;
-				snps,ref-clock-period-ns = <0x32>;
 				dr_mode = "host";
 			};
 		};
-- 
2.25.1