ixp4xx: Resurrect IXP4xx support using device tree
authorLinus Walleij <linus.walleij@linaro.org>
Mon, 23 Oct 2023 06:43:07 +0000 (08:43 +0200)
committerChristian Marangi <ansuelsmth@gmail.com>
Wed, 25 Oct 2023 09:28:38 +0000 (11:28 +0200)
This resurrects the support for IXP4xx using device tree
rather than the old (deleted) board files. The final pieces
of IXP4xx board files were deleted in Linux v5.19.

Ext4 root filesystems on CF and USB are supported by the
default config.

We support these three initial targets:

- The Gateworks Avila GW2348 reference design has 64MB of RAM
  and 32MB of flash and also supports USB and CompactFlash.

- The Gateworks Cambria GW2358 reference design has 128MB of
  RAM and 32MB of flash and also supports USB and CompactFlash.

- The old and stable Linksys NSLU2 works fine as well, albeit
  it only has 32MB of RAM so it has been marked as non-default.
  The 8MB of flash can only fit the kernel, so it has been
  patched to boot from exteral media on USB. I have used
  it successfully as a NAS with ksmbd and LUCI web API, see:
  https://dflund.se/~triad/krad/ixp4xx/

Signed-off-by: Howard Harte <hharte@magicandroidapps.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Tomasz Maciej Nowak <tmn505@gmail.com>
target/linux/ixp4xx/Makefile [new file with mode: 0644]
target/linux/ixp4xx/base-files/etc/board.d/02_network [new file with mode: 0644]
target/linux/ixp4xx/base-files/lib/preinit/05_set_ether_mac_ixp4xx [new file with mode: 0644]
target/linux/ixp4xx/config-6.1 [new file with mode: 0644]
target/linux/ixp4xx/image/Makefile [new file with mode: 0644]
target/linux/ixp4xx/patches-6.1/0001-mtd-cfi_cmdset_0001-Byte-swap-OTP-info.patch [new file with mode: 0644]
target/linux/ixp4xx/patches-6.1/301-ARM-dts-ixp4xx-Boot-NSLU2-from-harddrive.patch [new file with mode: 0644]

diff --git a/target/linux/ixp4xx/Makefile b/target/linux/ixp4xx/Makefile
new file mode 100644 (file)
index 0000000..89a1b24
--- /dev/null
@@ -0,0 +1,27 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Copyright (C) 2006-2023 OpenWrt.org
+
+include $(TOPDIR)/rules.mk
+
+ARCH:=armeb
+BOARD:=ixp4xx
+BOARDNAME:=Intel XScale IXP4xx
+FEATURES:=dt squashfs gpio
+CPU_TYPE:=xscale
+
+KERNEL_PATCHVER:=6.1
+
+define Target/Description
+       Build firmware images for the IXP4xx XScale CPU
+endef
+
+KERNELNAME:=zImage dtbs
+
+include $(INCLUDE_DIR)/target.mk
+
+DEFAULT_PACKAGES += fconfig \
+       kmod-usb-ledtrig-usbport \
+       kmod-leds-gpio
+
+$(eval $(call BuildTarget))
diff --git a/target/linux/ixp4xx/base-files/etc/board.d/02_network b/target/linux/ixp4xx/base-files/etc/board.d/02_network
new file mode 100644 (file)
index 0000000..45d7cbc
--- /dev/null
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0-only
+. /lib/functions/uci-defaults.sh
+
+board_config_update
+
+case "$(board_name)" in
+gateworks,gw2348|\
+gateworks,gw2358)
+       ucidef_set_interfaces_lan_wan "eth0" "eth1"
+       ;;
+linksys,nslu2)
+       ucidef_set_interface_lan "eth0" "dhcp"
+       ;;
+*)
+       ucidef_set_interface_lan "eth0" "dhcp"
+       ;;
+esac
+
+board_config_flush
+
+exit 0
diff --git a/target/linux/ixp4xx/base-files/lib/preinit/05_set_ether_mac_ixp4xx b/target/linux/ixp4xx/base-files/lib/preinit/05_set_ether_mac_ixp4xx
new file mode 100644 (file)
index 0000000..9e7ff46
--- /dev/null
@@ -0,0 +1,38 @@
+#!/bin/sh
+. /lib/functions.sh
+. /lib/functions/system.sh
+
+set_from_redboot () {
+       for npe in eth0 eth1 eth2
+       do
+               if ip link show dev $npe > /dev/null 2>&1; then
+                       ip link set dev $npe address $(fconfig -s -r -d /dev/$1 -n npe_"$npe"_esa)
+               fi
+       done
+
+       # Devices with MAC address set blank: set a dummy value.
+       if [ "$(ip link show dev eth0 2>/dev/null | grep -c 00:00:00:00:00:00)" = "1" ]; then
+               ip link set dev eth0 address 00:11:22:33:44:55
+       fi
+       if [ "$(ip link show dev eth1 2>/dev/null | grep -c 00:00:00:00:00:00)" = "1" ]; then
+               ip link set dev eth0 address 00:11:22:33:44:56
+       fi
+}
+
+set_from_sysconf () {
+       ip link set dev eth0 address $(mtd_get_mac_ascii SysConf hw_addr)
+}
+
+set_ether_mac () {
+       RBC="$(grep "RedBoot config" /proc/mtd | cut -d: -f1)"
+       if [ ! -z $RBC ] ; then
+               set_from_redboot $RBC
+       else
+               SYSC="$(grep "SysConf" /proc/mtd | cut -d: -f1)"
+               if [ ! -z $SYSC ] ; then
+                       set_from_sysconf
+               fi
+       fi
+}
+
+boot_hook_add preinit_main set_ether_mac
diff --git a/target/linux/ixp4xx/config-6.1 b/target/linux/ixp4xx/config-6.1
new file mode 100644 (file)
index 0000000..3b47385
--- /dev/null
@@ -0,0 +1,252 @@
+CONFIG_ALIGNMENT_TRAP=y
+CONFIG_ARCH_32BIT_OFF_T=y
+CONFIG_ARCH_HIBERNATION_POSSIBLE=y
+CONFIG_ARCH_IXP4XX=y
+CONFIG_ARCH_KEEP_MEMBLOCK=y
+CONFIG_ARCH_MIGHT_HAVE_PC_PARPORT=y
+CONFIG_ARCH_MULTIPLATFORM=y
+CONFIG_ARCH_MULTI_CPU_AUTO=y
+# CONFIG_ARCH_MULTI_V4 is not set
+# CONFIG_ARCH_MULTI_V4T is not set
+CONFIG_ARCH_MULTI_V4_V5=y
+CONFIG_ARCH_MULTI_V5=y
+CONFIG_ARCH_NR_GPIO=0
+CONFIG_ARCH_OPTIONAL_KERNEL_RWX=y
+CONFIG_ARCH_SELECT_MEMORY_MODEL=y
+CONFIG_ARCH_SPARSEMEM_ENABLE=y
+CONFIG_ARCH_SUSPEND_POSSIBLE=y
+CONFIG_ARM=y
+CONFIG_ARM_APPENDED_DTB=y
+# CONFIG_ARM_ATAG_DTB_COMPAT is not set
+CONFIG_ARM_HAS_GROUP_RELOCS=y
+CONFIG_ARM_L1_CACHE_SHIFT=5
+CONFIG_ARM_PATCH_PHYS_VIRT=y
+CONFIG_ARM_THUMB=y
+CONFIG_ARM_UNWIND=y
+CONFIG_ATA=y
+CONFIG_ATAGS=y
+CONFIG_AUTO_ZRELADDR=y
+CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK=y
+CONFIG_BLK_DEV_SD=y
+CONFIG_BLK_MQ_PCI=y
+CONFIG_CC_HAVE_STACKPROTECTOR_TLS=y
+CONFIG_CC_IMPLICIT_FALLTHROUGH="-Wimplicit-fallthrough=5"
+CONFIG_CC_NO_ARRAY_BOUNDS=y
+CONFIG_CLKSRC_MMIO=y
+CONFIG_CLONE_BACKWARDS=y
+CONFIG_COMMON_CLK=y
+CONFIG_COMPACT_UNEVICTABLE_DEFAULT=1
+CONFIG_COMPAT_32BIT_TIME=y
+CONFIG_CPU_32v5=y
+CONFIG_CPU_ABRT_EV5T=y
+CONFIG_CPU_BIG_ENDIAN=y
+CONFIG_CPU_CACHE_VIVT=y
+CONFIG_CPU_CP15=y
+CONFIG_CPU_CP15_MMU=y
+CONFIG_CPU_ENDIAN_BE32=y
+CONFIG_CPU_PABRT_LEGACY=y
+CONFIG_CPU_THUMB_CAPABLE=y
+CONFIG_CPU_TLB_V4WBI=y
+CONFIG_CPU_USE_DOMAINS=y
+CONFIG_CPU_XSCALE=y
+CONFIG_CRC16=y
+CONFIG_CRYPTO_AUTHENC=m
+CONFIG_CRYPTO_CBC=m
+CONFIG_CRYPTO_CRC32C=y
+CONFIG_CRYPTO_DES=m
+CONFIG_CRYPTO_DEV_IXP4XX=m
+CONFIG_CRYPTO_ECB=m
+CONFIG_CRYPTO_HW=y
+CONFIG_CRYPTO_LIB_BLAKE2S_GENERIC=y
+CONFIG_CRYPTO_LIB_DES=m
+CONFIG_CRYPTO_LIB_SHA1=y
+CONFIG_CRYPTO_LIB_UTILS=y
+CONFIG_CRYPTO_RNG2=y
+CONFIG_DEBUG_BUGVERBOSE=y
+CONFIG_DEBUG_INFO=y
+CONFIG_DEBUG_LL_INCLUDE="debug/8250.S"
+CONFIG_DEBUG_UART_8250=y
+CONFIG_DEBUG_UART_8250_SHIFT=2
+CONFIG_DEBUG_UART_PHYS=0xc8000003
+CONFIG_DEBUG_UART_VIRT=0xfec00003
+CONFIG_DMA_OPS=y
+CONFIG_DTC=y
+CONFIG_EDAC_ATOMIC_SCRUB=y
+CONFIG_EDAC_SUPPORT=y
+CONFIG_EXCLUSIVE_SYSTEM_RAM=y
+CONFIG_EXT4_FS=y
+# CONFIG_FARSYNC is not set
+CONFIG_FIXED_PHY=y
+CONFIG_FIX_EARLYCON_MEM=y
+CONFIG_FORCE_PCI=y
+CONFIG_FS_IOMAP=y
+CONFIG_FS_MBCACHE=y
+CONFIG_FWNODE_MDIO=y
+CONFIG_FW_LOADER_PAGED_BUF=y
+CONFIG_FW_LOADER_SYSFS=y
+CONFIG_GCC11_NO_ARRAY_BOUNDS=y
+CONFIG_GENERIC_ALLOCATOR=y
+CONFIG_GENERIC_ATOMIC64=y
+CONFIG_GENERIC_BUG=y
+CONFIG_GENERIC_CLOCKEVENTS=y
+CONFIG_GENERIC_CPU_AUTOPROBE=y
+CONFIG_GENERIC_EARLY_IOREMAP=y
+CONFIG_GENERIC_IDLE_POLL_SETUP=y
+CONFIG_GENERIC_IRQ_MULTI_HANDLER=y
+CONFIG_GENERIC_IRQ_SHOW=y
+CONFIG_GENERIC_IRQ_SHOW_LEVEL=y
+CONFIG_GENERIC_LIB_DEVMEM_IS_ALLOWED=y
+CONFIG_GENERIC_PCI_IOMAP=y
+CONFIG_GENERIC_SCHED_CLOCK=y
+CONFIG_GENERIC_SMP_IDLE_THREAD=y
+CONFIG_GENERIC_STRNCPY_FROM_USER=y
+CONFIG_GENERIC_STRNLEN_USER=y
+CONFIG_GLOB=y
+CONFIG_GPIOLIB_IRQCHIP=y
+CONFIG_GPIO_CDEV=y
+CONFIG_GPIO_GENERIC=y
+CONFIG_GPIO_GW_PLD=y
+CONFIG_GPIO_IXP4XX=y
+CONFIG_HARDIRQS_SW_RESEND=y
+CONFIG_HAS_DMA=y
+CONFIG_HAS_IOMEM=y
+CONFIG_HAS_IOPORT_MAP=y
+CONFIG_HDLC=y
+CONFIG_HWMON=y
+CONFIG_HWMON_VID=y
+CONFIG_HW_RANDOM=y
+CONFIG_HW_RANDOM_IXP4XX=y
+CONFIG_HZ_FIXED=0
+CONFIG_HZ_PERIODIC=y
+CONFIG_I2C=y
+CONFIG_I2C_ALGOBIT=y
+CONFIG_I2C_BOARDINFO=y
+CONFIG_I2C_CHARDEV=y
+CONFIG_I2C_GPIO=y
+CONFIG_I2C_IOP3XX=y
+CONFIG_INITRAMFS_SOURCE=""
+CONFIG_INTEL_IXP4XX_EB=y
+CONFIG_IRQCHIP=y
+CONFIG_IRQSTACKS=y
+CONFIG_IRQ_DOMAIN=y
+CONFIG_IRQ_DOMAIN_HIERARCHY=y
+CONFIG_IRQ_FORCED_THREADING=y
+CONFIG_IRQ_WORK=y
+# CONFIG_IWMMXT is not set
+CONFIG_IXP4XX_ETH=y
+CONFIG_IXP4XX_HSS=y
+CONFIG_IXP4XX_IRQ=y
+CONFIG_IXP4XX_NPE=y
+CONFIG_IXP4XX_QMGR=y
+CONFIG_IXP4XX_TIMER=y
+CONFIG_IXP4XX_WATCHDOG=y
+CONFIG_JBD2=y
+CONFIG_LEDS_GPIO=y
+CONFIG_LEGACY_PTYS=y
+CONFIG_LEGACY_PTY_COUNT=256
+CONFIG_LIBFDT=y
+CONFIG_LOCK_DEBUGGING_SUPPORT=y
+CONFIG_MDIO_BUS=y
+CONFIG_MDIO_DEVICE=y
+CONFIG_MDIO_DEVRES=y
+CONFIG_MEMFD_CREATE=y
+CONFIG_MFD_SYSCON=y
+CONFIG_MIGRATION=y
+CONFIG_MODULES_USE_ELF_REL=y
+CONFIG_MTD_CFI_ADV_OPTIONS=y
+# CONFIG_MTD_CFI_GEOMETRY is not set
+CONFIG_MTD_OTP=y
+CONFIG_MTD_PHYSMAP=y
+CONFIG_MTD_PHYSMAP_IXP4XX=y
+CONFIG_MTD_REDBOOT_PARTS=y
+CONFIG_MTD_SPLIT_FIRMWARE=y
+CONFIG_MTD_SPLIT_FIRMWARE_NAME="linux"
+CONFIG_NEED_DMA_MAP_STATE=y
+CONFIG_NEED_KUSER_HELPERS=y
+CONFIG_NEED_PER_CPU_KM=y
+CONFIG_NET_DSA=y
+CONFIG_NET_DSA_MV88E6060=y
+CONFIG_NET_PTP_CLASSIFY=y
+CONFIG_NET_SELFTESTS=y
+CONFIG_NET_VENDOR_XSCALE=y
+CONFIG_NLS=y
+CONFIG_NVMEM=y
+CONFIG_NVMEM_SYSFS=y
+CONFIG_OF=y
+CONFIG_OF_ADDRESS=y
+CONFIG_OF_EARLY_FLATTREE=y
+CONFIG_OF_FLATTREE=y
+CONFIG_OF_GPIO=y
+CONFIG_OF_IRQ=y
+CONFIG_OF_KOBJ=y
+CONFIG_OF_MDIO=y
+# CONFIG_OLD_SIGACTION is not set
+# CONFIG_OLD_SIGSUSPEND3 is not set
+CONFIG_PAGE_OFFSET=0xC0000000
+CONFIG_PAGE_POOL=y
+CONFIG_PAGE_SIZE_LESS_THAN_256KB=y
+CONFIG_PAGE_SIZE_LESS_THAN_64KB=y
+CONFIG_PATA_IXP4XX_CF=y
+CONFIG_PCI=y
+CONFIG_PCI_DOMAINS=y
+CONFIG_PCI_DOMAINS_GENERIC=y
+CONFIG_PCI_IXP4XX=y
+CONFIG_PERF_USE_VMALLOC=y
+CONFIG_PGTABLE_LEVELS=2
+CONFIG_PHYLIB=y
+CONFIG_POWER_RESET=y
+CONFIG_POWER_RESET_GPIO=y
+CONFIG_PREEMPT_NONE_BUILD=y
+CONFIG_PTP_1588_CLOCK_OPTIONAL=y
+CONFIG_RANDSTRUCT_NONE=y
+CONFIG_RATIONAL=y
+CONFIG_REALTEK_PHY=y
+CONFIG_REGMAP=y
+CONFIG_REGMAP_I2C=y
+CONFIG_REGMAP_MMIO=y
+CONFIG_RUST_IS_AVAILABLE=y
+CONFIG_SCSI=y
+CONFIG_SCSI_COMMON=y
+# CONFIG_SERIAL_8250_EXAR is not set
+# CONFIG_SERIAL_8250_FSL is not set
+# CONFIG_SERIAL_8250_PCI is not set
+# CONFIG_SERIAL_8250_PERICOM is not set
+CONFIG_SERIAL_MCTRL_GPIO=y
+CONFIG_SERIAL_OF_PLATFORM=y
+CONFIG_SG_POOL=y
+CONFIG_SOFTIRQ_ON_OWN_STACK=y
+CONFIG_SPARSE_IRQ=y
+CONFIG_SPLIT_PTLOCK_CPUS=999999
+CONFIG_SRCU=y
+CONFIG_SWPHY=y
+CONFIG_SYS_SUPPORTS_APM_EMULATION=y
+CONFIG_THREAD_INFO_IN_TASK=y
+CONFIG_TICK_CPU_ACCOUNTING=y
+CONFIG_TIMER_OF=y
+CONFIG_TIMER_PROBE=y
+CONFIG_TINY_SRCU=y
+CONFIG_UNCOMPRESS_INCLUDE="debug/uncompress.h"
+CONFIG_UNWINDER_ARM=y
+CONFIG_USB=y
+CONFIG_USB_COMMON=y
+CONFIG_USB_EHCI_BIG_ENDIAN_DESC=y
+CONFIG_USB_EHCI_BIG_ENDIAN_MMIO=y
+CONFIG_USB_EHCI_HCD=y
+CONFIG_USB_EHCI_HCD_PLATFORM=y
+CONFIG_USB_EHCI_PCI=y
+CONFIG_USB_OHCI_HCD=y
+CONFIG_USB_OHCI_HCD_PCI=y
+# CONFIG_USB_OHCI_HCD_PLATFORM is not set
+CONFIG_USB_PCI=y
+CONFIG_USB_STORAGE=y
+CONFIG_USB_SUPPORT=y
+CONFIG_USB_UHCI_HCD=y
+CONFIG_USE_OF=y
+CONFIG_VM_EVENT_COUNTERS=y
+CONFIG_WAN=y
+CONFIG_WATCHDOG_CORE=y
+CONFIG_WATCHDOG_NOWAYOUT=y
+CONFIG_XZ_DEC_ARM=y
+CONFIG_XZ_DEC_BCJ=y
+CONFIG_ZBOOT_ROM_BSS=0x0
+CONFIG_ZBOOT_ROM_TEXT=0x0
diff --git a/target/linux/ixp4xx/image/Makefile b/target/linux/ixp4xx/image/Makefile
new file mode 100644 (file)
index 0000000..0bcabe2
--- /dev/null
@@ -0,0 +1,77 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Copyright (C) 2006-2021 OpenWrt.org
+
+include $(TOPDIR)/rules.mk
+include $(INCLUDE_DIR)/image.mk
+
+# Cook a Linksys NSLU2 etc image
+define Build/linksys-ixp425-image
+       touch $@.null-initrd
+       $(TOPDIR)/scripts/slugimage.pl -L $(STAGING_DIR_IMAGE)/apex/apex-$(1)-armeb.bin -k $@ -r $@.null-initrd -p -o $@.new
+       mv $@.new $@
+endef
+
+# Build sysupgrade image
+define BuildFirmware/Generic
+       dd if=$(KDIR)/zImage of=$(KDIR)/zImage.pad bs=64k conv=sync; \
+       dd if=$(KDIR)/root.$(1) of=$(KDIR)/root.$(1).pad bs=128k conv=sync; \
+       sh $(TOPDIR)/scripts/combined-image.sh \
+               $(KDIR)/zImage.pad \
+               $(KDIR)/root.$(1).pad \
+               $(BIN_DIR)/$(IMG_PREFIX)-$(patsubst jffs2-%,jffs2,$(patsubst squashfs-%,squashfs,$(1)))-sysupgrade.bin
+endef
+
+define Image/Build
+       $(call Image/Build/$(1),$(1))
+       $(call BuildFirmware/Generic,$(1))
+endef
+
+define Device/Default
+       PROFILES := Default
+       KERNEL_DEPENDS = $$(wildcard $(DTS_DIR)/$$(DEVICE_DTS).dts)
+       KERNEL_NAME := zImage
+       KERNEL := kernel-bin | append-dtb
+       BLOCKSIZE := 128k
+endef
+
+define Device/gateworks_avila
+       DEVICE_VENDOR := Gateworks
+       DEVICE_MODEL := Avila GW2348-4
+       DEVICE_PACKAGES := ixp4xx-microcode-ethernet kmod-rtc-ds1672 kmod-eeprom-at24 kmod-hwmon-ad7418
+       DEVICE_DTS := intel-ixp42x-gateworks-gw2348
+       KERNEL := kernel-bin | append-dtb
+       IMAGES := kernel.bin rootfs.bin
+       IMAGE/kernel.bin := append-kernel
+       IMAGE/rootfs.bin := append-rootfs | pad-rootfs | pad-to 128k
+endef
+TARGET_DEVICES += gateworks_avila
+
+define Device/gateworks_cambria
+       DEVICE_VENDOR := Gateworks
+       DEVICE_MODEL := Cambria GW2358-4
+       DEVICE_PACKAGES := ixp4xx-microcode-ethernet kmod-rtc-ds1672 kmod-eeprom-at24 kmod-hwmon-ad7418
+       DEVICE_DTS := intel-ixp43x-gateworks-gw2358
+       KERNEL := kernel-bin | append-dtb
+       IMAGES := kernel.bin rootfs.bin
+       IMAGE/kernel.bin := append-kernel
+       IMAGE/rootfs.bin := append-rootfs | pad-rootfs | pad-to 128k
+endef
+TARGET_DEVICES += gateworks_cambria
+
+define Device/linksys_nslu2
+       DEVICE_VENDOR := Linksys
+       DEVICE_MODEL := NSLU2
+       # USB2 is compiled in and needs no package
+       DEVICE_PACKAGES := ixp4xx-microcode-ethernet kmod-rtc-x1205
+       # Only 32 MB of RAM so not building by default
+       DEFAULT := n
+       DEVICE_DTS := intel-ixp42x-linksys-nslu2
+       KERNEL := kernel-bin | append-dtb
+       IMAGES := factory.bin
+       # This has to boot from harddisk so just append the kernel
+       IMAGE/factory.bin := append-kernel | linksys-ixp425-image "nslu2"
+endef
+TARGET_DEVICES += linksys_nslu2
+
+$(eval $(call BuildImage))
diff --git a/target/linux/ixp4xx/patches-6.1/0001-mtd-cfi_cmdset_0001-Byte-swap-OTP-info.patch b/target/linux/ixp4xx/patches-6.1/0001-mtd-cfi_cmdset_0001-Byte-swap-OTP-info.patch
new file mode 100644 (file)
index 0000000..1c5e44b
--- /dev/null
@@ -0,0 +1,74 @@
+From 4e242d6e08ad1d85b832e158cd0eafcb8f3f76a1 Mon Sep 17 00:00:00 2001
+From: Linus Walleij <linus.walleij@linaro.org>
+Date: Tue, 30 May 2023 22:40:31 +0200
+Subject: [PATCH v3] mtd: cfi_cmdset_0001: Byte swap OTP info
+
+Currently the offset into the device when looking for OTP
+bits can go outside of the address of the MTD NOR devices,
+and if that memory isn't readable, bad things happen
+on the IXP4xx (added prints that illustrate the problem before
+the crash):
+
+cfi_intelext_otp_walk walk OTP on chip 0 start at reg_prot_offset 0x00000100
+ixp4xx_copy_from copy from 0x00000100 to 0xc880dd78
+cfi_intelext_otp_walk walk OTP on chip 0 start at reg_prot_offset 0x12000000
+ixp4xx_copy_from copy from 0x12000000 to 0xc880dd78
+8<--- cut here ---
+Unable to handle kernel paging request at virtual address db000000
+[db000000] *pgd=00000000
+(...)
+
+This happens in this case because the IXP4xx is big endian and
+the 32- and 16-bit fields in the struct cfi_intelext_otpinfo are not
+properly byteswapped. Compare to how the code in read_pri_intelext()
+byteswaps the fields in struct cfi_pri_intelext.
+
+Adding a small byte swapping loop for the OTP in read_pri_intelext()
+and the crash goes away.
+
+The problem went unnoticed for many years until I enabled
+CONFIG_MTD_OTP on the IXP4xx as well, triggering the bug.
+
+Cc: Nicolas Pitre <npitre@baylibre.com>
+Cc: stable@vger.kernel.org
+Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
+---
+ChangeLog v2->v3:
+- Move the byte swapping to a small loop in read_pri_intelext()
+  so all bytes are swapped as we reach cfi_intelext_otp_walk().
+ChangeLog v1->v2:
+- Drill deeper and discover a big endian compatibility issue.
+---
+ drivers/mtd/chips/cfi_cmdset_0001.c | 20 ++++++++++++++++++--
+ 1 file changed, 18 insertions(+), 2 deletions(-)
+
+--- a/drivers/mtd/chips/cfi_cmdset_0001.c
++++ b/drivers/mtd/chips/cfi_cmdset_0001.c
+@@ -421,9 +421,25 @@ read_pri_intelext(struct map_info *map,
+               extra_size = 0;
+               /* Protection Register info */
+-              if (extp->NumProtectionFields)
++              if (extp->NumProtectionFields) {
++                      struct cfi_intelext_otpinfo *otp =
++                              (struct cfi_intelext_otpinfo *)&extp->extra[0];
++
+                       extra_size += (extp->NumProtectionFields - 1) *
+-                                    sizeof(struct cfi_intelext_otpinfo);
++                              sizeof(struct cfi_intelext_otpinfo);
++
++                      if (extp_size >= sizeof(*extp) + extra_size) {
++                              int i;
++
++                              /* Do some byteswapping if necessary */
++                              for (i = 0; i < extp->NumProtectionFields - 1; i++) {
++                                      otp->ProtRegAddr = le32_to_cpu(otp->ProtRegAddr);
++                                      otp->FactGroups = le16_to_cpu(otp->FactGroups);
++                                      otp->UserGroups = le16_to_cpu(otp->UserGroups);
++                                      otp++;
++                              }
++                      }
++              }
+       }
+       if (extp->MinorVersion >= '1') {
diff --git a/target/linux/ixp4xx/patches-6.1/301-ARM-dts-ixp4xx-Boot-NSLU2-from-harddrive.patch b/target/linux/ixp4xx/patches-6.1/301-ARM-dts-ixp4xx-Boot-NSLU2-from-harddrive.patch
new file mode 100644 (file)
index 0000000..ffd69a7
--- /dev/null
@@ -0,0 +1,24 @@
+From 2792791a19f90b0141ed2e781599ba0a42a8cfd5 Mon Sep 17 00:00:00 2001
+From: Linus Walleij <linus.walleij@linaro.org>
+Date: Mon, 29 May 2023 23:32:44 +0200
+Subject: [PATCH] ARM: dts: ixp4xx: Boot NSLU2 from harddrive
+
+This enforces harddrive boot on the NSLU2. The flash is too small
+to hold any rootfs these days.
+
+Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
+---
+ arch/arm/boot/dts/intel-ixp42x-linksys-nslu2.dts | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/arch/arm/boot/dts/intel-ixp42x-linksys-nslu2.dts
++++ b/arch/arm/boot/dts/intel-ixp42x-linksys-nslu2.dts
+@@ -21,7 +21,7 @@
+       };
+       chosen {
+-              bootargs = "console=ttyS0,115200n8 root=/dev/mtdblock2 rw rootfstype=squashfs,jffs2 rootwait";
++              bootargs = "console=ttyS0,115200n8 root=/dev/sda1 rw rootwait";
+               stdout-path = "uart0:115200n8";
+       };