[PATCH v2 3/3] arm64: dts: renesas: r8a779g3: Describe split PCIe clock on V4H Sparrow Hawk

[Marek Vasut]

The V4H Sparrow Hawk board supplies PCIe controller input clock and PCIe
bus clock from separate outputs of Renesas 9FGV0441 clock generator chip.
Describe this split bus configuration in the board DT. The topology looks
as follows:

 ____________                    _____________
| R-Car PCIe |                  | PCIe device |
|            |                  |             |
|    PCIe RX<|==================|>PCIe TX     |
|    PCIe TX<|==================|>PCIe RX     |
|            |                  |             |
|   PCIe CLK<|======..  ..======|>PCIe CLK    |
'------------'      ||  ||      '-------------'
                    ||  ||
 ____________       ||  ||
|  9FGV0441  |      ||  ||
|            |      ||  ||
|   CLK DIF0<|======''  ||
|   CLK DIF1<|==========''
|   CLK DIF2<|
|   CLK DIF3<|
'------------'

Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
---
Cc: Bartosz Golaszewski <brgl at bgdev.pl>
Cc: Bjorn Helgaas <bhelgaas at google.com>
Cc: Conor Dooley <conor+dt at kernel.org>
Cc: Geert Uytterhoeven <geert+renesas at glider.be>
Cc: Krzysztof Kozlowski <krzk+dt at kernel.org>
Cc: Magnus Damm <magnus.damm at gmail.com>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam at linaro.org>
Cc: Rob Herring <robh at kernel.org>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh at renesas.com>
Cc: devicetree at vger.kernel.org
Cc: linux-kernel at vger.kernel.org
Cc: linux-pci at vger.kernel.org
Cc: linux-renesas-soc at vger.kernel.org
---
V2: Use pciec0_rp/pciec1_rp phandles to refer to root port moved to core r8a779g0.dtsi
---
 .../dts/renesas/r8a779g3-sparrow-hawk.dts     | 31 +++++++++++++++++--
 1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk.dts b/arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk.dts
index b8698e07add56..9ba23129e65ec 100644
--- a/arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk.dts
+++ b/arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk.dts
@@ -130,6 +130,13 @@ mini_dp_con_in: endpoint {
 		};
 	};
 
+	/* Page 26 / PCIe.0/1 CLK */
+	pcie_refclk: clk-x8 {
+		compatible = "fixed-clock";
+		#clock-cells = <0>;
+		clock-frequency = <25000000>;
+	};
+
 	reg_1p2v: regulator-1p2v {
 		compatible = "regulator-fixed";
 		regulator-name = "fixed-1.2V";
@@ -404,6 +411,14 @@ i2c0_mux2: i2c at 2 {
 			reg = <2>;
 			#address-cells = <1>;
 			#size-cells = <0>;
+
+			/* Page 26 / PCIe.0/1 CLK */
+			pcie_clk: clk at 68 {
+				compatible = "renesas,9fgv0441";
+				reg = <0x68>;
+				clocks = <&pcie_refclk>;
+				#clock-cells = <1>;
+			};
 		};
 
 		i2c0_mux3: i2c at 3 {
@@ -487,26 +502,38 @@ msiof1_snd_endpoint: endpoint {
 
 /* Page 26 / 2230 Key M M.2 */
 &pcie0_clkref {
-	clock-frequency = <100000000>;
+	status = "disabled";
 };
 
 &pciec0 {
+	clocks = <&cpg CPG_MOD 624>, <&pcie_clk 0>;
 	reset-gpios = <&gpio2 2 GPIO_ACTIVE_LOW>;
 	status = "okay";
 };
 
+&pciec0_rp {
+	clocks = <&pcie_clk 1>;
+	vpcie3v3-supply = <&reg_3p3v>;
+};
+
 /* Page 25 / PCIe to USB */
 &pcie1_clkref {
-	clock-frequency = <100000000>;
+	status = "disabled";
 };
 
 &pciec1 {
+	clocks = <&cpg CPG_MOD 625>, <&pcie_clk 2>;
 	/* uPD720201 is PCIe Gen2 x1 device */
 	num-lanes = <1>;
 	reset-gpios = <&gpio2 0 GPIO_ACTIVE_LOW>;
 	status = "okay";
 };
 
+&pciec1_rp {
+	clocks = <&pcie_clk 3>;
+	vpcie3v3-supply = <&reg_3p3v>;
+};
+
 &pfc {
 	pinctrl-0 = <&scif_clk_pins>;
 	pinctrl-names = "default";
-- 
2.47.2