arm64: dts: ti: am62-lp-sk: Add overlay for NAND expansion card

The NAND expansion card (PROC143E1) connects over the User/MCU/PRU
Expansion port on the am62-lp-sk EVM.

The following pins are shared between McASP1 and GPMC-NAND so
both cannot work simultaneously.

Pin name	McASP1 function		GPMC function
========	===============		=============
J17		MCASP1_AXR0		GPMC0_WEN
P21		MCASP1_AFSX		GPMC0_WAIT0
K17		MCASP1_ACLKX		GPMC0_BE0N_CLE
K20		MCASP1_AXR2		GPMC0_ADVN_ALE

The factory default sets the pins for McASP1 use. (i.e.
Resistor Array RA1 installed, RA4 not installed).

For NAND use, RA1 has to be removed and RA4 must be
installed.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
Link: https://lore.kernel.org/r/20240622-am62lp-sk-nand-v1-2-caee496eaf42@kernel.org
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>

Author: rogerq

arch/arm64/boot/dts/ti/Makefile

@@ -25,6 +25,7 @@ dtb-$(CONFIG_ARCH_K3) += k3-am625-verdin-wifi-yavia.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am625-phyboard-lyra-1-4-ghz-opp.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-am62x-phyboard-lyra-gpio-fan.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-am62-lp-sk.dtb
+dtb-$(CONFIG_ARCH_K3) += k3-am62-lp-sk-nand.dtbo
 
 # Boards with AM62Ax SoC
 dtb-$(CONFIG_ARCH_K3) += k3-am62a7-sk.dtb

arch/arm64/boot/dts/ti/k3-am62-lp-sk-nand.dtso

@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022-2024 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+/dts-v1/;
+/plugin/;
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/interrupt-controller/irq.h>
+#include "k3-pinctrl.h"
+
+&mcasp1 {
+	status = "disabled";
+};
+
+&main_pmx0 {
+	gpmc0_pins_default: gpmc0-pins-default {
+		pinctrl-single,pins = <
+			AM62X_IOPAD(0x003c, PIN_INPUT, 0) /* (K19) GPMC0_AD0 */
+			AM62X_IOPAD(0x0040, PIN_INPUT, 0) /* (L19) GPMC0_AD1 */
+			AM62X_IOPAD(0x0044, PIN_INPUT, 0) /* (L20) GPMC0_AD2 */
+			AM62X_IOPAD(0x0048, PIN_INPUT, 0) /* (L21) GPMC0_AD3 */
+			AM62X_IOPAD(0x004c, PIN_INPUT, 0) /* (M21) GPMC0_AD4 */
+			AM62X_IOPAD(0x0050, PIN_INPUT, 0) /* (L17) GPMC0_AD5 */
+			AM62X_IOPAD(0x0054, PIN_INPUT, 0) /* (L18) GPMC0_AD6 */
+			AM62X_IOPAD(0x0058, PIN_INPUT, 0) /* (M20) GPMC0_AD7 */
+			AM62X_IOPAD(0x0098, PIN_INPUT, 0) /* (P21) GPMC0_WAIT0 */
+			AM62X_IOPAD(0x00a8, PIN_OUTPUT, 0) /* (J18) GPMC0_CSn0 */
+			AM62X_IOPAD(0x0084, PIN_OUTPUT, 0) /* (K20) GPMC0_ADVn_ALE */
+			AM62X_IOPAD(0x0088, PIN_OUTPUT, 0) /* (K21) GPMC0_OEn_REn */
+			AM62X_IOPAD(0x008c, PIN_OUTPUT, 0) /* (J17) GPMC0_WEn */
+			AM62X_IOPAD(0x0090, PIN_OUTPUT, 0) /* (K17) GPMC0_BE0n_CLE */
+			AM62X_IOPAD(0x00a0, PIN_OUTPUT, 0) /* (J20) GPMC0_WPn */
+		>;
+	};
+};
+
+&elm0 {
+	status = "okay";
+};
+
+&gpmc0 {
+	status = "okay";
+	pinctrl-names = "default";
+	pinctrl-0 = <&gpmc0_pins_default>;
+	#address-cells = <2>;
+	#size-cells = <1>;
+
+	nand@0,0 {
+		compatible = "ti,am64-nand";
+		reg = <0 0 64>;		/* device IO registers */
+		interrupt-parent = <&gpmc0>;
+		interrupts = <0 IRQ_TYPE_NONE>, /* fifoevent */
+			     <1 IRQ_TYPE_NONE>;	/* termcount */
+		rb-gpios = <&gpmc0 0 GPIO_ACTIVE_HIGH>;	/* gpmc_wait0 */
+		ti,nand-xfer-type = "prefetch-polled";
+		ti,nand-ecc-opt = "bch8";	/* BCH8: Bootrom limitation */
+		ti,elm-id = <&elm0>;
+		nand-bus-width = <8>;
+		gpmc,device-width = <1>;
+		gpmc,sync-clk-ps = <0>;
+		gpmc,cs-on-ns = <0>;
+		gpmc,cs-rd-off-ns = <40>;
+		gpmc,cs-wr-off-ns = <40>;
+		gpmc,adv-on-ns = <0>;
+		gpmc,adv-rd-off-ns = <25>;
+		gpmc,adv-wr-off-ns = <25>;
+		gpmc,we-on-ns = <0>;
+		gpmc,we-off-ns = <20>;
+		gpmc,oe-on-ns = <3>;
+		gpmc,oe-off-ns = <30>;
+		gpmc,access-ns = <30>;
+		gpmc,rd-cycle-ns = <40>;
+		gpmc,wr-cycle-ns = <40>;
+		gpmc,bus-turnaround-ns = <0>;
+		gpmc,cycle2cycle-delay-ns = <0>;
+		gpmc,clk-activation-ns = <0>;
+		gpmc,wr-access-ns = <40>;
+		gpmc,wr-data-mux-bus-ns = <0>;
+
+		partitions {
+			compatible = "fixed-partitions";
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			partition@0 {
+				label = "NAND.tiboot3";
+				reg = <0x00000000 0x00200000>;	/* 2M */
+			};
+			partition@200000 {
+				label = "NAND.tispl";
+				reg = <0x00200000 0x00200000>;	/* 2M */
+			};
+			partition@400000 {
+				label = "NAND.tiboot3.backup";	/* 2M */
+				reg = <0x00400000 0x00200000>;	/* BootROM looks at 4M */
+			};
+			partition@600000 {
+				label = "NAND.u-boot";
+				reg = <0x00600000 0x00400000>;	/* 4M */
+			};
+			partition@a00000 {
+				label = "NAND.u-boot-env";
+				reg = <0x00a00000 0x00040000>;	/* 256K */
+			};
+			partition@a40000 {
+				label = "NAND.u-boot-env.backup";
+				reg = <0x00a40000 0x00040000>;	/* 256K */
+			};
+			partition@a80000 {
+				label = "NAND.file-system";
+				reg = <0x00a80000 0x3f580000>;
+			};
+		};
+	};
+};

arch/arm64/boot/dts/ti/k3-am62-lp-sk.dts

@@ -228,3 +228,7 @@
 &tlv320aic3106 {
 	DVDD-supply = <&buck2_reg>;
 };
+
+&gpmc0 {
+	ranges = <0 0 0x00 0x51000000 0x01000000>; /* CS0 space. Min partition = 16MB */
+};