[PATCH RFC v2 11/11] PoC: arm64: dts: imx93-11x11-frdm: add multiple vdevs

[Francesco Valla]

Add rings and buffers for multiple virtio devices exposed by the
firmware running on the Cortex-M33 processor which is part of the i.MX93.
It is expected that such firmware exposes, through its resource table,
the following vdevs:

  - vdev0: rpmsg
  - vdev1: entropy
  - vdev2: gpio
  - vdev3: i2c
  - vdev4: spi
  - vdev5: can

The order in which the devices are contained inside the resource table
is critical, since it is used both to associate vrings and buffers to a
vdev and to map additional dt nodes to them.

All vdev buffers except the one for the rpmsg bus are declared as
restricted-dma-pool, because the corresponding drivers need bounce
buffering for the communication to work correctly.

Nodes for the gpio and i2c vdevs with example children devices are
included.

NOTE: this is a Proof-Of-Concept, not meant to be integrated!

Signed-off-by: Francesco Valla <francesco at valla.it>

---

Notable diff from RFC v1: the rsc-table node has been re-introduced to
focus on the changes that are truly in scope for the series. I still
believe something is off with the current implementation, but I'll
tackle it separately.
---
 arch/arm64/boot/dts/freescale/imx93-11x11-frdm.dts | 188 +++++++++++++++++++++
 1 file changed, 188 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx93-11x11-frdm.dts b/arch/arm64/boot/dts/freescale/imx93-11x11-frdm.dts
index 6e8351d12016..84324b02c45d 100644
--- a/arch/arm64/boot/dts/freescale/imx93-11x11-frdm.dts
+++ b/arch/arm64/boot/dts/freescale/imx93-11x11-frdm.dts
@@ -137,3 +137,191 @@ MX93_PAD_SD3_DATA3__GPIO3_IO25		0x31e
 		>;
 	};
 };
+
+/* Multi-vdev PoC */
+
+#include <dt-bindings/input/linux-event-codes.h>
+
+/ {
+	reserved-memory {
+		rsc_table: rsc-table at 2021e000 {
+			reg = <0 0x2021e000 0 0x1000>;
+			no-map;
+		};
+
+		/* vdev0: rpmsg */
+		vdev0vring0: vdev0vring0 at a4000000 {
+			reg = <0 0xa4000000 0 0x8000>;
+			no-map;
+		};
+
+		vdev0vring1: vdev0vring1 at a4008000 {
+			reg = <0 0xa4008000 0 0x8000>;
+			no-map;
+		};
+
+		vdev0buffer: vdev0buffer at a4020000 {
+			compatible = "shared-dma-pool";
+			reg = <0 0xa4020000 0 0x100000>;
+			no-map;
+		};
+
+		/* vdev1: entropy */
+		vdev1vring0: vdev1vring0 at a4010000 {
+			reg = <0 0xa4010000 0 0x1000>;
+			no-map;
+		};
+
+		/delete-node/ vdev1vring1 at a4018000;
+
+		vdev1buffer: vdev1buffer at a4120000 {
+			compatible = "restricted-dma-pool";
+			reg = <0 0xa4120000 0 0x10000>;
+		};
+
+		/* vdev2: GPIO */
+		vdev2vring0: vdev2vring0 at a4011000 {
+			reg = <0 0xa4011000 0 0x2000>;
+			no-map;
+		};
+
+		vdev2vring1: vdev2vring1 at a4013000 {
+			reg = <0 0xa4013000 0 0x2000>;
+			no-map;
+		};
+
+		vdev2buffer: vdev2buffer at a4130000 {
+			compatible = "restricted-dma-pool";
+			reg = <0 0xa4130000 0 0x20000>;
+		};
+
+		/* vdev3: I2C */
+		vdev3vring0: vdev3vring0 at a4015000 {
+			reg = <0 0xa4015000 0 0x2000>;
+			no-map;
+		};
+
+		vdev3buffer: vdev3buffer at a4150000 {
+			compatible = "restricted-dma-pool";
+			reg = <0 0xa4150000 0 0x20000>;
+		};
+
+		/* vdev4: SPI */
+		vdev4vring0: vdev4vring0 at a4017000 {
+			reg = <0 0xa4017000 0 0x4000>;
+			no-map;
+		};
+
+		vdev4buffer: vdev4buffer at a4170000 {
+			compatible = "restricted-dma-pool";
+			reg = <0 0xa4170000 0 0x90000>;
+		};
+
+		/* vdev5: CAN */
+		vdev5vring0: vdev5vring0 at a401b000 {
+			reg = <0 0xa401b000 0 0x2000>;
+			no-map;
+		};
+
+		vdev5vring1: vdev5vring1 at a401d000 {
+			reg = <0 0xa401d000 0 0x2000>;
+			no-map;
+		};
+
+		vdev5vring2: vdev5vring2 at a401f000 {
+			reg = <0 0xa401f000 0 0x1000>;
+			no-map;
+		};
+
+		vdev5buffer: vdev5buffer at a4200000 {
+			compatible = "restricted-dma-pool";
+			reg = <0 0xa4200000 0 0x80000>;
+		};
+	};
+
+	gpio-keys-virtio {
+		compatible = "gpio-keys";
+
+		button-v1 {
+			label = "Button V1";
+			linux,code = <BTN_3>;
+			gpios = <&v_gpio 23 GPIO_ACTIVE_LOW>;
+		};
+
+		button-v2 {
+			label = "Button V2";
+			linux,code = <BTN_4>;
+			gpios = <&v_gpio 24 GPIO_ACTIVE_LOW>;
+		};
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		led {
+			gpios = <&v_gpio 18 GPIO_ACTIVE_HIGH>;
+			label = "LED V";
+		};
+	};
+};
+
+&cm33 {
+	memory-region = <&vdev0buffer>, <&vdev0vring0>, <&vdev0vring1>,
+			<&vdev1vring0>, <&vdev2vring0>, <&vdev2vring1>,
+			<&vdev3vring0>, <&vdev4vring0>, <&vdev5vring0>,
+			<&vdev5vring1>, <&vdev5vring2>, <&rsc_table>;
+
+	virtio {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		/* vdev1: entropy */
+		vdev at 1 {
+			reg = <1>;
+			memory-region = <&vdev1buffer>;
+		};
+
+		/* vdev2: GPIO */
+		vdev at 2 {
+			reg = <2>;
+			memory-region = <&vdev2buffer>;
+
+			v_gpio: gpio {
+				compatible = "virtio,device29";
+				gpio-controller;
+				#gpio-cells = <2>;
+				interrupt-controller;
+				#interrupt-cells = <2>;
+			};
+		};
+
+		/* vdev3: I2C */
+		vdev at 3 {
+			reg = <3>;
+			memory-region = <&vdev3buffer>;
+
+			i2c {
+				compatible = "virtio,device22";
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				eeprom at 50 {
+					compatible = "atmel,24c1025";
+					reg = <0x50>;
+				};
+			};
+		};
+
+		/* vdev4: SPI */
+		vdev at 4 {
+			reg = <4>;
+			memory-region = <&vdev4buffer>;
+		};
+
+		/* vdev5: CAN */
+		vdev at 5 {
+			reg = <5>;
+			memory-region = <&vdev5buffer>;
+		};
+	};
+};

-- 
2.56.0