econet: Add basic USB support with Mass Storage

The EN751221 has an XHCI that is compatible with MT7621.
While there is setup logic in the vendor code for both
EN751221 and MT7621, but MT7621 does not use it in mainline
or OpenWRT, and it appears to work correctly with EN751221.

Include SCSI / Mass Storage because many EcoNet devices
contain a builtin USB SD-Card reader.

Signed-off-by: Caleb James DeLisle <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/20050
[Remove usb storage kmod from smartfiber_xp8421-b]
Signed-off-by: Hauke Mehrtens <[email protected]>

package/kernel/linux/modules/usb.mk

@@ -1845,6 +1845,7 @@ define KernelPackage/usb3
 	+TARGET_bcm53xx:kmod-usb-bcma \
 	+TARGET_bcm53xx:kmod-phy-bcm-ns-usb3 \
 	+TARGET_ramips_mt7621:kmod-usb-xhci-mtk \
+	+TARGET_econet_en751221:kmod-usb-xhci-mtk \
 	+TARGET_mediatek:kmod-usb-xhci-mtk
   KCONFIG:= \
 	CONFIG_USB_PCI=y \

target/linux/econet/Makefile

@@ -7,7 +7,7 @@ include $(TOPDIR)/rules.mk
 ARCH:=mips
 BOARD:=econet
 BOARDNAME:=EcoNet EN75xx MIPS
-FEATURES:=dt source-only squashfs nand
+FEATURES:=dt source-only squashfs nand usb
 SUBTARGETS:=en751221
 
 KERNEL_PATCHVER:=6.12
@@ -19,4 +19,7 @@ endef
 # include the profiles
 include $(INCLUDE_DIR)/target.mk
 
+# nand-utils is used by base-files/sbin/en75_chboot
+DEFAULT_PACKAGES += nand-utils
+
 $(eval $(call BuildTarget))

target/linux/econet/dts/en751221.dtsi

@@ -56,6 +56,20 @@
 		econet,shadow-interrupts = <7 2>, <8 3>, <13 12>, <30 29>;
 	};
 
+    usb: usb@1fb90000 {
+            compatible = "mediatek,mt8173-xhci", "mediatek,mtk-xhci";
+            reg = <0x1fb90000 0x4000>,
+                  <0x1fa80700 0x100>;
+            reg-names = "mac", "ippc";
+
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            interrupt-parent = <&intc>;
+            interrupts = <17>;
+            usb3-lpm-capable;
+    };
+
 	uart: serial@1fbf0000 {
 		compatible = "ns16550";
 		reg = <0x1fbf0000 0x30>;

target/linux/econet/en751221/config-6.12

@@ -39,6 +39,8 @@ CONFIG_CRYPTO_LZO=y
 CONFIG_CRYPTO_ZSTD=y
 CONFIG_DEBUG_INFO=y
 CONFIG_DEBUG_ZBOOT=y
+CONFIG_DMA_NEED_SYNC=y
+CONFIG_DMA_NONCOHERENT=y
 CONFIG_DTB_ECONET_NONE=y
 # CONFIG_DTB_ECONET_SMARTFIBER_XP8421_B is not set
 CONFIG_DTC=y
@@ -110,6 +112,7 @@ CONFIG_MTD_UBI=y
 CONFIG_MTD_UBI_BEB_LIMIT=13
 CONFIG_MTD_UBI_BLOCK=y
 CONFIG_MTD_UBI_WL_THRESHOLD=4096
+CONFIG_NEED_DMA_MAP_STATE=y
 CONFIG_NEED_SRCU_NMI_SAFE=y
 CONFIG_NET_EGRESS=y
 CONFIG_NET_FLOW_LIMIT=y
@@ -168,6 +171,7 @@ CONFIG_TIMER_PROBE=y
 CONFIG_TREE_RCU=y
 CONFIG_TREE_SRCU=y
 CONFIG_UBIFS_FS=y
+CONFIG_USB_SUPPORT=y
 CONFIG_USE_GENERIC_EARLY_PRINTK_8250=y
 CONFIG_USE_OF=y
 CONFIG_XPS=y

target/linux/econet/image/en751221.mk

@@ -4,6 +4,7 @@ define Device/smartfiber_xp8421-b
   DEVICE_DTS := en751221_smartfiber_xp8421-b
   IMAGES := tclinux.trx
   IMAGE/tclinux.trx := append-kernel | lzma | tclinux-trx
+  DEVICE_PACKAGES := kmod-usb3
 endef
 TARGET_DEVICES += smartfiber_xp8421-b
 

target/linux/econet/patches-6.12/310-usb-enable-econet-usb.patch

@@ -0,0 +1,21 @@
+--- a/arch/mips/Kconfig
++++ b/arch/mips/Kconfig
+@@ -392,6 +392,7 @@ config ECONET
+ 	bool "EcoNet MIPS family"
+ 	select BOOT_RAW
+ 	select CPU_BIG_ENDIAN
++	select DMA_NONCOHERENT
+ 	select DEBUG_ZBOOT if DEBUG_KERNEL
+ 	select EARLY_PRINTK_8250
+ 	select ECONET_EN751221_TIMER
+--- a/drivers/usb/host/Kconfig
++++ b/drivers/usb/host/Kconfig
+@@ -71,7 +71,7 @@ config USB_XHCI_HISTB
+ config USB_XHCI_MTK
+ 	tristate "xHCI support for MediaTek SoCs"
+ 	select MFD_SYSCON
+-	depends on (MIPS && SOC_MT7621) || ARCH_MEDIATEK || COMPILE_TEST
++	depends on (MIPS && SOC_MT7621) || ECONET || ARCH_MEDIATEK || COMPILE_TEST
+ 	help
+ 	  Say 'Y' to enable the support for the xHCI host controller
+ 	  found in MediaTek SoCs.