first boot on armv7 / Turris Omnia

Presently either you run this from U-Boot or you figure out for
yourself how to kexecboot into a recovery system :-)

THOUGHTS.txt

@@ -2436,3 +2436,258 @@ Sun Sep 17 16:44:31 BST 2023
 Can we figure out which bits of the old doc are missing from the new
 one and just transplant those? Then we can merge it sooner
 instead of blocking on writig all the new stuff
+
+Mon Sep 25 16:58:51 BST 2023
+
+jffs2 on mt300a isn't finding root partition in initramfs, and it
+seems to be because MTD_SPLIT_UIMAGE_FW isn't working
+
+[    0.426792] spi spi0.0: force spi mode3
+[    0.431305] spi-nor spi0.0: w25q128 (16384 Kbytes)
+[    0.436322] 5 fixed-partitions partitions found on MTD device spi0.0
+[    0.442875] OF: Bad cell count for /palmbus@10000000/spi@b00/flash@0/partitions
+[    0.450400] OF: Bad cell count for /palmbus@10000000/spi@b00/flash@0/partitions
+[    0.458208] OF: Bad cell count for /palmbus@10000000/spi@b00/flash@0/partitions
+[    0.465751] OF: Bad cell count for /palmbus@10000000/spi@b00/flash@0/partitions
+[    0.473522] Creating 5 MTD partitions on "spi0.0":
+[    0.478466] 0x000000000000-0x000000030000 : "u-boot"
+[    0.484447] 0x000000030000-0x000000040000 : "u-boot-env"
+[    0.490888] 0x000000040000-0x000000050000 : "factory"
+[    0.497110] 0x000000050000-0x000000fd0000 : "firmware"
+[    0.596423] 0x000000ff0000-0x000001000000 : "art"
+[    0.611508] gsw: setting port4 to ephy mode
+
+with squashfs root it's the same but for the extra split partitions:
+
+[    0.468715] Creating 5 MTD partitions on "spi0.0":
+[    0.473653] 0x000000000000-0x000000030000 : "u-boot"
+[    0.479652] 0x000000030000-0x000000040000 : "u-boot-env"
+[    0.486085] 0x000000040000-0x000000050000 : "factory"
+[    0.492318] 0x000000050000-0x000000fd0000 : "firmware"
+[    0.499304] 2 uimage-fw partitions found on MTD device firmware
+[    0.505457] Creating 2 MTD partitions on "firmware":
+[    0.510543] 0x000000000000-0x000000260000 : "kernel"
+[    0.516616] 0x000000260000-0x000000f80000 : "rootfs"
+[    0.522570] mtd: device 5 (rootfs) set to be root filesystem
+[    0.528565] 0x000000ff0000-0x000001000000 : "art"
+
+turns out this is because the device thinks it has 4k erase block size
+because MTD_SPI_NOR_USE_4K_SECTORS was set, and that was causing
+mtdsplit to look in the wrong place for a root filesystem
+
+Mon Sep 25 18:50:05 BST 2023
+
+No, that wasn't it. Turned out to be an endianness-dependent check for
+JFFS2 magic in mtdsplit.
+
+setenv serverip 10.0.0.1
+setenv ipaddr 10.0.0.8
+tftp 0xa00000 result/uimage
+bootm 0xa00000
+
+Fri Sep 29 20:50:39 BST 2023
+
+setenv bootargs 'liminix mtdparts=phram0:M(rootfs) phram.phram=phram0,0x40411f28,4194304,65536 memmap=4194304$0x40411f28 root=/dev/mtdblock0 console=ttyAMA0,115200 earlycon'
+
+setenv serverip 10.0.0.1
+setenv ipaddr 10.0.0.5
+setenv bootargs 'liminix console=ttyS0,115200  panic=10 oops=panic earlycon=uart8250,mmio32,0x11002000 root=/dev/mtdblock0'
+tftp 0x4007ff28 result/uimage ;  tftp 0x40432f28 result/rootfs
+bootm 0x4007ff28
+
+setenv bootargs 'liminix console=ttyS0,115200  panic=1 oops=panic earlycon  root=/dev/mtdblock0'
+
+md 0x42ff0000
+
+Cannot find regmap for /infracfg@10000000: -524.
+
+# "console=ttyAMA0,38400 panic=10 oops=panic init=/bin/init loglevel=8 root=/dev/mtdblock0 rootfstype=squashfs fw_devlink=off"
+
+
+40812468: 69726553 203a6c61 41424d41 304c5020    Serial: AMBA PL0
+40812478: 55203131 20545241 76697264 3c0a7265    11 UART driver.<
+40812488: 61723e33 706f6f6d 61203a73 6165726c    3>ramoops: alrea
+40812498: 69207964 6974696e 7a696c61 3c0a6465    dy initialized.<
+408124a8: 61723e34 706f6f6d 70203a73 65626f72    4>ramoops: probe
+408124b8: 20666f20 66663234 30303030 6d61722e     of 42ff0000.ram
+408124c8: 73706f6f 69616620 2064656c 68746977    oops failed with
+408124d8: 72726520 2d20726f 3c0a3232 61433e33     error -22.<3>Ca
+408124e8: 746f6e6e 6e696620 65722064 70616d67    nnot find regmap
+408124f8: 726f6620 6e692f20 63617266 31406766     for /infracfg@1
+40812508: 30303030 3a303030 32352d20 333c0a34    0000000: -524.<3
+40812518: 6e61433e 20746f6e 646e6966 67657220    >Cannot find reg
+MT7622>
+40812528: 2070616d 20726f66 666e692f 66636172    map for /infracf
+40812538: 30314067 30303030 203a3030 3432352d    g@10000000: -524
+40812548: 3e333c0a 6e6e6143 6620746f 20646e69    .<3>Cannot find
+40812558: 6d676572 66207061 2f20726f 72666e69    regmap for /infr
+40812568: 67666361 30303140 30303030 2d203a30    acfg@10000000: -
+40812578: 0a343235 433e333c 6f6e6e61 69662074    524.<3>Cannot fi
+40812588: 7220646e 616d6765 6f662070 702f2072    nd regmap for /p
+40812598: 63697265 31406766 32303030 3a303030    ericfg@10002000:
+408125a8: 32352d20 313c0a34 616e553e 20656c62     -524.<1>Unable
+408125b8: 68206f74 6c646e61 656b2065 6c656e72    to handle kernel
+408125c8: 67617020 20676e69 75716572 20747365     paging request
+408125d8: 76207461 75747269 61206c61 65726464    at virtual addre
+408125e8: 66207373 66666666 66666666 66666666    ss fffffffffffff
+408125f8: 0a656666 4d3e313c 61206d65 74726f62    ffe.<1>Mem abort
+
+
+CONFIG_SERIAL_8250_FSL=y
+CONFIG_SERIAL_8250_MT6577=y
+CONFIG_SERIAL_8250_NR_UARTS=3
+CONFIG_SERIAL_8250_RUNTIME_UARTS=3
+CONFIG_SERIAL_DEV_BUS=y
+CONFIG_SERIAL_DEV_CTRL_TTYPORT=y
+CONFIG_SERIAL_MCTRL_GPIO=y
+CONFIG_SERIAL_OF_PLATFORM=y
+
+Mon Oct  2 10:17:04 BST 2023
+
+We have a bootable aarch64 kernel for the Belkin, but it does not
+understand the memmap= parameter we're using to protect the
+phram image from being used as general memory.
+
+One option is to add a reserved-memory stanza in the device tree,
+using u-boot "fdt" command, but we don't know the fdt address in u-boot
+because it doesn't have any commands to parse the image and set
+variables pointing at the sub-components. (There's iminfo, but it's
+onyl human-readable)
+
+Second option is to amend the dtb in the tftpboot module: this
+would mean regenerating the uimage
+
+Third option: for tftpboot do we _have_ to use FIT? maybe we could
+grab the fdt as a separate tftp transaction
+
+we need to apply kernel patch 9401911f2d9f89035f7acebab16e72d43d1282fb
+to avoid using ioremap on sysem ram which is not allowed on arm
+
+
+Tue Oct  3 14:15:38 BST 2023
+
+Progress on Liminix ARM support. The device I'm starting with is
+the Belkin RT3200 (also known as [Linksys E8450](https://openwrt.org/toh/linksys/e8450)) which seems to be a featureful piece of kit, and whioch I snagged for a
+very good price on the Bay of E
+
+# Where are we right now?
+
+* we can TFTP boot it to userland
+* ethernet works
+
+## What else needs doing?
+
+* it has dual band wifi with many interesting features. I've built the
+
+* we're only running in RAM, probably need to add some kernel config
+  to support the flash
+* initramfs support is not yet implemented
+* the flash is NAND flash and it's quite large compared with the
+  existing Liminix devices, so we're going to add UBIFS which will
+  use it better than  JFFS2 does
+* all this work is on a branch and needs to be cleaned up a lot before
+   I'm letting it into main
+
+## What have we found?
+
+There are some significant differences between this and the MIPS
+devices (yes, other than an entirely different architecture), mostly
+to do with "legacy boot" support or the lack thereof. For example:
+
+* there aren't any options like `MIPS_RAW_APPENDED_DTB` to glom
+  together a kernel and device tree (FDT), because the bootloader is
+  expected to be able to provide a FDT following "standards".
+  U-Boot will do this, provided that we use the newer "FIT" Uimage
+  format which allows a kernel and DTB and initrd to be combined in
+  the same container.  (Sadly we can't use FIT everywhere because a
+  lot of MIPS devices use really old forks of U-Boot that don't
+  understand it)
+
+* for tftpboot, on MIPS we use the `memmap` kernel command line option
+  to reserve some RAM for the root filesystem. On Arm there's no such
+  option, so we have to add a
+  [reserved-memory](https://github.com/torvalds/linux/blob/master/Documentation/devicetree/bindings/reserved-memory/reserved-memory.yaml)
+  node in the device tree instead. Which means, given that we _only_
+  want to do this when tftp booting (the memory is wasted
+  otherwise), we have to rewrite the device tree in that
+  scenario.
+
+* then it turns out that phram doesn't (didn't) work anyway, because
+  it calls ioremap() and [you can't use ioremap on system memory on ARM](https://lwn.net/Articles/409689/). In newer kernels this is
+  fixed: there is a [conditional](https://github.com/torvalds/linux/blob/master/drivers/mtd/devices/phram.c#L127) here to use whichever of ioremap or
+  memremap is appropriate for the memory passed to phram, but it looks
+  non-trivial to backport so I've gone for a [much less sophisticated approach](https://gti.telent.net/dan/liminix/commit/f7cd9c2b6e6c99a228e066b09e3febcf71c63fa1#diff-d8e355f1b2dcde7378ebb40c92cdd2ce3125753c)
+
+* we're using [DSA](https://www.kernel.org/doc/Documentation/networking/dsa/dsa.txt) instead of the OpenWrt [swconfig](https://openwrt.org/docs/techref/swconfig) program. There was actually surprisingly little work needed to adjust to this.
+
+
+Other than that, it was mostly the usual process of "did the kernel
+crash silently, or has it just been unable to open a console device?".
+In this regard, *one neat trick*: even though U-Boot on this device
+doesn't support pstore, we can use it anyway if we don't do compression.
+Enable
+
+```
+        PSTORE = "y";
+        PSTORE_RAM = "y";
+        PSTORE_CONSOLE = "y";
+        PSTORE_DEFLATE_COMPRESS = "n";
+```
+
+then boot with `panic=3 oops=panic`, then when it resets use the
+U_Boot `md` command to see what happened:
+
+```
+MT7622> md 0x42ff0000
+42ff0000: 43474244 00000000 00000ff4 3d3d3d3d    DBGC........====
+42ff0010: 39342e31 36373031 500a442d 63696e61    1.491076-D.Panic
+42ff0020: 50203123 31747261 3e363c0a 20505050    #1 Part1.<6>PPP
+42ff0030: 20445342 706d6f43 73736572 206e6f69    BSD Compression
+[....]
+42ff0ca0: 20676e69 73756e75 6b206465 656e7265    ing unused kerne
+42ff0cb0: 656d206c 79726f6d 3731203a 0a4b3832    l memory: 1728K.
+42ff0cc0: 523e363c 2f206e75 74696e69 20736120    <6>Run /init as
+42ff0cd0: 74696e69 6f727020 73736563 3e373c0a    init process.<7>
+```
+
+Wed Oct  4 21:08:44 BST 2023
+
+By randomly including chinks of the openwrt config we have made it
+find the mt7915e on the pcie bus. I just don't yet know which bit of
+the openwrt config it was.
+
+It doesn't actually work yet though. 5GHz wifi gets calibration data
+from the flash, so it is not going to work unless (1) we reflash the
+firmware partition, or (2) we find another way to provide it
+calibration data.
+
+https://forum.openwrt.org/t/belkin-rt3200-linksys-e8450-wifi-ax-discussion/94302/401
+
+Sat Oct  7 22:56:40 BST 2023
+
+We're almost ready to merge the rt3200 support (it's not finished
+but it mostly won't break mips) except for the uimage module
+which needs all that FIT stuff, and the tftpboot contortions
+to amend the dtb for memmap
+
+For legacy uimage
+
+1) add commandline params to dtb
+2) objcopy fdt into vmlinux.elf
+3) strip to raw image and compress
+4) mkimage
+
+
+For FIT uimage
+
+1) add commandline params to dtb
+2) strip to raw image and compress
+3) create its file
+4) mkimage
+
+Do we still want to handle the no-dtb case? what about
+standards-compliant boot, where u-boot is providing the dtb? No option
+to provide a commandline in that case, but maybe also no need to.
+
+For tftpboot, am undecided. We could use the dtb rewriting thing
+everywhere, in the interest of consistency.

devices/belkin-rt3200/default.nix

@@ -0,0 +1,205 @@
+{
+  description = ''
+    Belkin RT-3200 / Linksys E8450
+    ******************************
+
+    This device is based on a 64 bit Mediatek MT7622 ARM platform,
+    and is "work in progress" in Liminix.
+
+    The factory flash image contains ECC errors that make it incompatible
+    with Liminix: you need to use the `OpenWrt UBI Installer <https://github.com/dangowrt/owrt-ubi-installer>`_ to rewrite the partition layout before
+    you can flash Liminix onto it (or even use it with "tftpboot",
+    if you want the wireless to work).
+
+    - MediaTek MT7622BV (1350MHz)
+    - 128MB NAND flash
+    - 512MB	RAM
+    - b/g/n wireless using MediaTek MT7622BV (MT7615E driver)
+    - a/n/ac/ax wireless using  MediaTek MT7915E
+  '';
+
+  system = {
+    crossSystem = {
+      config = "aarch64-unknown-linux-musl";
+    };
+  };
+
+  module = {pkgs, config, lib, ... }:
+    let firmware = pkgs.stdenv.mkDerivation {
+          name = "wlan-firmware";
+          phases = ["installPhase"];
+          installPhase = ''
+            mkdir $out
+            cp ${pkgs.linux-firmware}/lib/firmware/mediatek/{mt7915,mt7615,mt7622}* $out
+          '';
+        };
+    in {
+    imports = [ ../../modules/arch/aarch64.nix ];
+    kernel = {
+      src = pkgs.pkgsBuildBuild.fetchurl {
+        name = "linux.tar.gz";
+        url = "https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.15.71.tar.gz";
+        hash = "sha256-yhO2cXIeIgUxkSZf/4aAsF11uxyh+UUZu6D1h92vCD8=";
+      };
+      extraPatchPhase = ''
+          ${pkgs.openwrt.applyPatches.mediatek}
+      '';
+      config = {
+        PCI = "y";
+        ARCH_MEDIATEK = "y";
+        # ARM_MEDIATEK_CPUFREQ = "y";
+
+        # needed for "Cannot find regmap for /infracfg@10000000"
+        MFD_SYSCON = "y";
+        MTK_INFRACFG = "y";
+
+        MTK_PMIC_WRAP = "y";
+        MTK_EFUSE="y";
+        # MTK_HSDMA="y";
+        MTK_SCPSYS="y";
+        MTK_SCPSYS_PM_DOMAINS="y";
+        # MTK_THERMAL="y";
+        MTK_TIMER="y";
+
+        COMMON_CLK_MT7622 = "y";
+        COMMON_CLK_MT7622_ETHSYS = "y";
+        COMMON_CLK_MT7622_HIFSYS = "y";
+        COMMON_CLK_MT7622_AUDSYS = "y";
+        PM_CLK="y";
+
+        REGMAP_MMIO = "y";
+        CLKSRC_MMIO = "y";
+        REGMAP = "y";
+
+        MEDIATEK_GE_PHY = "y";
+        # MEDIATEK_MT6577_AUXADC = "y";
+        # MEDIATEK_WATCHDOG = "y";
+        NET_MEDIATEK_SOC = "y";
+        NET_MEDIATEK_SOC_WED = "y";
+        NET_MEDIATEK_STAR_EMAC = "y"; # this enables REGMAP_MMIO
+        NET_VENDOR_MEDIATEK = "y";
+        PCIE_MEDIATEK = "y";
+
+        BLOCK = "y"; # move this to base option
+
+        SPI_MASTER = "y";
+        SPI = "y";
+        SPI_MEM="y";
+        SPI_MTK_NOR="y";
+        SPI_MTK_SNFI = "y";
+
+        MTD = "y";
+        MTD_BLOCK = "y";
+        MTD_RAW_NAND = "y";
+        MTD_NAND_MTK = "y";
+        MTD_NAND_MTK_BMT = "y";      # Bad-block Management Table
+        MTD_NAND_ECC_MEDIATEK= "y";
+        MTD_NAND_ECC_SW_HAMMING= "y";
+        MTD_SPI_NAND= "y";
+        MTD_OF_PARTS = "y";
+        MTD_NAND_CORE= "y";
+        MTD_SPI_NOR= "y";
+        MTD_SPLIT_FIRMWARE= "y";
+        MTD_SPLIT_FIT_FW= "y";
+
+
+        MMC = "y";
+        MMC_BLOCK = "y";
+        MMC_CQHCI = "y";
+        MMC_MTK = "y";
+
+        # Distributed Switch Architecture is needed
+        # to make the ethernet ports visible
+        NET_DSA="y";
+        NET_DSA_MT7530="y";
+        NET_DSA_TAG_MTK="y";
+
+        PSTORE = "y";
+        PSTORE_RAM = "y";
+        PSTORE_CONSOLE = "y";
+        PSTORE_DEFLATE_COMPRESS = "n";
+
+        SERIAL_8250 = "y";
+        SERIAL_8250_CONSOLE = "y";
+        SERIAL_8250_MT6577="y";
+        # SERIAL_8250_NR_UARTS="3";
+        # SERIAL_8250_RUNTIME_UARTS="3";
+        SERIAL_OF_PLATFORM="y";
+      };
+    };
+    boot = {
+      commandLine = [ "console=ttyS0,115200" ];
+      tftp.loadAddress =  "0x4007ff28";
+      imageFormat = "fit";
+    };
+    filesystem =
+      let inherit (pkgs.pseudofile) dir symlink;
+           in
+             dir {
+               lib = dir {
+                 firmware = dir {
+                   mediatek = symlink firmware;
+                 };
+               };
+             };
+
+    hardware =
+      let
+        openwrt = pkgs.openwrt;
+        mac80211 =  pkgs.mac80211.override {
+          drivers = [
+            "mt7615e"
+            "mt7915e"
+          ];
+          klibBuild = config.system.outputs.kernel.modulesupport;
+        };
+      in {
+        ubi = {
+          minIOSize = "2048";
+          eraseBlockSize = "126976";
+          maxLEBcount = "1024"; # guessing
+        };
+
+        defaultOutput = "flashimage";
+        # the kernel expects this to be on a 2MB boundary. U-Boot
+        # (I don't know why) has a default of 0x41080000, which isn't.
+        # We put it at the 32MB mark so that tftpboot can put its rootfs
+        # image and DTB underneath, but maybe this is a terrible waste of
+        # RAM unless the kernel is able to reuse it later. Oh well
+        loadAddress = "0x42000000";
+        entryPoint  = "0x42000000";
+        rootDevice = "ubi0:liminix";
+        dts = {
+          src = "${openwrt.src}/target/linux/mediatek/dts/mt7622-linksys-e8450-ubi.dts";
+          includes =  [
+            "${openwrt.src}/target/linux/mediatek/dts"
+            "${config.system.outputs.kernel.modulesupport}/arch/arm64/boot/dts/mediatek/"
+          ];
+        };
+
+        flash.eraseBlockSize = "65536"; # this is probably wrong
+        networkInterfaces =
+          let
+            inherit (config.system.service.network) link;
+            inherit (config.system.service) bridge;
+          in rec {
+            wan = link.build { ifname = "wan"; };
+            lan1 = link.build { ifname = "lan1"; };
+            lan2 = link.build { ifname = "lan2"; };
+            lan3 = link.build { ifname = "lan3"; };
+            lan4 = link.build { ifname = "lan4"; };
+            lan = lan3;
+
+            wlan = link.build {
+              ifname = "wlan0";
+              dependencies = [ mac80211 ];
+            };
+            wlan5 = link.build {
+              ifname = "wlan1";
+              dependencies = [ mac80211 ];
+            };
+          };
+      };
+
+  };
+}

devices/gl-ar750/default.nix

@@ -175,7 +175,6 @@
           CONSOLE_LOGLEVEL_QUIET = "4";
 
           NET = "y";
-          NETDEVICES = "y";
           ETHERNET = "y";
           NET_VENDOR_ATHEROS = "y";
           AG71XX = "y";             # ethernet (qca,qca9530-eth)

devices/gl-mt300a/default.nix

@@ -159,7 +159,6 @@
           CONSOLE_LOGLEVEL_QUIET = "4";
 
           NET = "y";
-          NETDEVICES = "y";
           ETHERNET = "y";
           NET_VENDOR_RALINK = "y";
           NET_RALINK_MDIO = "y";

devices/gl-mt300n-v2/default.nix

@@ -143,7 +143,6 @@
           REGULATOR_FIXED_VOLTAGE = "y";
 
           NET = "y";
-          NETDEVICES = "y";
           ETHERNET = "y";
 
           PHYLIB = "y";

devices/qemu-aarch64/default.nix

@@ -34,7 +34,6 @@
         VIRTIO_PCI = "y";
         BLOCK = "y";
         VIRTIO_BLK = "y";
-        NETDEVICES = "y";
         VIRTIO_NET = "y";
 
         SERIAL_EARLYCON_ARM_SEMIHOST = "y"; # earlycon=smh
@@ -42,6 +41,9 @@
         SERIAL_AMBA_PL011_CONSOLE = "y";
       };
     };
+    boot.commandLine = [
+      "console=ttyAMA0,38400"
+    ];
     hardware =
       let
         mac80211 =  pkgs.mac80211.override {

devices/qemu/default.nix

@@ -60,7 +60,6 @@
         VIRTIO_PCI = "y";
         BLOCK = "y";
         VIRTIO_BLK = "y";
-        NETDEVICES = "y";
         VIRTIO_NET = "y";
 
         SERIAL_8250= "y";

devices/turris-omnia/default.nix

@@ -0,0 +1,111 @@
+{
+  description = ''
+    Turris Omnia
+    ************
+  '';
+
+  system = {
+    crossSystem = {
+      config = "armv7l-unknown-linux-musleabihf";
+    };
+  };
+
+  module = {pkgs, config, lib, ... }:
+    let openwrt = pkgs.openwrt; in {
+    imports = [ ../../modules/arch/arm.nix ];
+    kernel = {
+      src = pkgs.pkgsBuildBuild.fetchurl {
+        name = "linux.tar.gz";
+        url = "https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.15.71.tar.gz";
+        hash = "sha256-yhO2cXIeIgUxkSZf/4aAsF11uxyh+UUZu6D1h92vCD8=";
+      };
+      extraPatchPhase = ''
+          ${pkgs.openwrt.applyPatches.mvebu}
+      '';
+      config = {
+        PCI = "y";
+        OF = "y";
+        MEMORY = "y"; # for MVEBU_DEVBUS
+        DMADEVICES = "y"; # for MV_XOR
+        CPU_V7 = "y";
+        ARCH_MULTIPLATFORM = "y";
+        ARCH_MVEBU = "y";
+        ARCH_MULTI_V7= "y";
+        PCI_MVEBU = "y";
+        AHCI_MVEBU = "y";
+        MACH_ARMADA_38X = "y";
+        SMP = "y";
+        NR_CPUS = "4";
+        VFP = "y";
+        NEON= "y";
+
+        # WARNING: unmet direct dependencies detected for ARCH_WANT_LIBATA_LEDS
+        ATA = "y";
+
+        # switch is DSA
+        # CONFIG_NET_DSA_MV88E6060=y
+        #   CONFIG_NET_DSA_MV88E6XXX=y
+        #     CONFIG_NET_DSA_MV88E6XXX_GLOBAL2=y
+
+        #         CONFIG_REGMAP=y
+        # CONFIG_REGMAP_I2C=y
+        # CONFIG_REGMAP_SPI=y
+        # CONFIG_REGMAP_MMIO=y
+
+        PSTORE = "y";
+        PSTORE_RAM = "y";
+        PSTORE_CONSOLE = "y";
+        PSTORE_DEFLATE_COMPRESS = "n";
+
+        SERIAL_8250 = "y";
+        SERIAL_8250_CONSOLE = "y";
+        SERIAL_OF_PLATFORM="y";
+        SERIAL_MVEBU_UART = "y";
+        SERIAL_MVEBU_CONSOLE = "y";
+
+        SERIAL_8250_DMA= "y";
+        SERIAL_8250_DW= "y";
+        SERIAL_8250_EXTENDED= "y";
+        SERIAL_8250_MANY_PORTS= "y";
+        SERIAL_8250_SHARE_IRQ= "y";
+        OF_ADDRESS= "y";
+        OF_MDIO= "y";
+
+        MVEBU_DEVBUS= "y"; # "Device Bus controller ...  flash devices such as NOR, NAND, SRAM, and FPGA"
+        MVMDIO= "y";
+        MVNETA= "y";
+        MVNETA_BM= "y";
+        MVNETA_BM_ENABLE= "y";
+        MVPP2= "y";
+        MV_XOR= "y";
+      };
+    };
+    boot = {
+      commandLine = [ "console=ttyS0,115200" ];
+      imageFormat = "fit";
+    };
+
+    hardware = {
+        defaultOutput = "flashimage";
+        loadAddress = "0x00008000";
+        entryPoint = "0x00008000";
+        rootDevice = "/dev/mtdblock0";
+        dts = {
+          src = "${config.system.outputs.kernel.modulesupport}/arch/arm/boot/dts/armada-385-turris-omnia.dts";
+          includes =  [
+            # "${openwrt.src}/target/linux/mediatek/dts"
+            "${config.system.outputs.kernel.modulesupport}/arch/arm/boot/dts/"
+          ];
+        };
+
+        networkInterfaces =
+          let
+            inherit (config.system.service.network) link;
+            inherit (config.system.service) bridge;
+          in rec {
+            lan = link.build { ifname = "eth0"; };
+          };
+      };
+
+  };
+}

modules/arch/aarch64.nix

@@ -6,14 +6,11 @@
       CPU_BIG_ENDIAN= "n";
       # CMDLINE_FROM_BOOTLOADER availability is conditional
       # on CMDLINE being set to something non-empty
-      CMDLINE="\"console=ttyAMA0\"";
+      CMDLINE="\"empty=false\"";
       CMDLINE_FROM_BOOTLOADER = "y";
 
       OF = "y";
       # USE_OF = "y";
     };
-    boot.commandLine = [
-      "console=ttyAMA0,38400"
-    ];
   };
 }

modules/base.nix

@@ -39,7 +39,7 @@ in {
     };
     rootfsType =  mkOption {
       default = "squashfs";
-      type = types.enum ["squashfs" "jffs2"];
+      type = types.enum ["squashfs" "jffs2" "ubifs"];
     };
     boot = {
       commandLine = mkOption {
@@ -47,6 +47,10 @@ in {
         default = [];
         description = "Kernel command line";
       };
+      imageFormat = mkOption {
+        type = types.enum ["fit" "uimage"];
+        default = "uimage";
+      };
       tftp = {
         loadAddress = mkOption {
           type = types.str;

modules/kernel.nix

@@ -64,6 +64,8 @@ in {
         PACKET = "y";           # for ppp, tcpdump ...
         SYSVIPC= "y";
 
+        NETDEVICES = "y";       # even PPP needs this
+
         # disabling this option causes the kernel to use an "empty"
         # initramfs instead: it has a /dev/console node and not much
         # else.  Note that pid 1 is started *before* the root

modules/outputs.nix

@@ -78,6 +78,7 @@ in
       uimage = liminix.builders.uimage {
         commandLine = concatStringsSep " " config.boot.commandLine;
         inherit (config.hardware) loadAddress entryPoint;
+        inherit (config.boot) imageFormat;
         inherit kernel;
         inherit dtb;
       };

modules/standard.nix

@@ -7,5 +7,6 @@
     ./kexecboot.nix
     ./flashimage.nix
     ./jffs2.nix
+    ./ubifs.nix
   ];
 }

modules/tftpboot.nix

@@ -42,27 +42,39 @@ in {
           ln -s ${o.manifest} manifest
           ln -s ${o.kernel.headers} build
           ln -s ${o.uimage} uimage
-          ln -s ${o.boot-scr} boot.scr
+          ln -s ${o.boot-scr}/dtb dtb
+          ln -s ${o.boot-scr}/script boot.scr
        '';
 
       boot-scr =
         let
           inherit (pkgs.lib.trivial) toHexString;
           o = config.system.outputs;
+          cmdline = concatStringsSep " " config.boot.commandLine;
         in
-          pkgs.buildPackages.runCommand "boot-scr" {} ''
+          pkgs.buildPackages.runCommand "boot-scr" { nativeBuildInputs = [ pkgs.pkgsBuildBuild.dtc ];  } ''
             uimageSize=$(($(stat -L -c %s ${o.uimage}) + 0x1000 &(~0xfff)))
-            rootfsStart=0x$(printf %x $((${cfg.loadAddress} + 0x100000 + $uimageSize)))
+            rootfsStart=0x$(printf %x $((${cfg.loadAddress} + 0x100000 + $uimageSize   &(~0xfffff) )))
             rootfsBytes=$(($(stat -L -c %s ${o.rootfs}) + 0x100000 &(~0xfffff)))
             rootfsBytes=$(($rootfsBytes + ${toString cfg.freeSpaceBytes} ))
-            cmd="mtdparts=phram0:''${rootfsMb}M(rootfs) phram.phram=phram0,''${rootfsStart},''${rootfsBytes},${config.hardware.flash.eraseBlockSize} memmap=''${rootfsBytes}\$''${rootfsStart} root=/dev/mtdblock0";
+            rootfsMb=$(($rootfsBytes >> 20))
+            cmd="mtdparts=phram0:''${rootfsMb}M(rootfs) phram.phram=phram0,''${rootfsStart},''${rootfsBytes},${config.hardware.flash.eraseBlockSize} root=/dev/mtdblock0";
 
-            cat > $out << EOF
+            dtbStart=$(printf %x $((${cfg.loadAddress} + $rootfsBytes + 0x100000 + $uimageSize )))
+
+            mkdir $out
+            cat ${o.dtb} > $out/dtb
+            fdtput -p -t s $out/dtb /reserved-memory/phram-rootfs compatible phram
+            fdtput -p -t lx $out/dtb /reserved-memory/phram-rootfs reg 0 $rootfsStart 0 $(printf %x $rootfsBytes)
+
+            dtbBytes=$(($(stat -L -c %s $out/dtb) + 0x1000 &(~0xfff)))
+
+            cat > $out/script << EOF
             setenv serverip ${cfg.serverip}
             setenv ipaddr ${cfg.ipaddr}
-            setenv bootargs 'liminix $cmd'
-            tftp 0x$(printf %x ${cfg.loadAddress}) result/uimage ; tftp 0x$(printf %x $rootfsStart) result/rootfs
-            bootm 0x$(printf %x ${cfg.loadAddress})
+            setenv bootargs 'liminix ${cmdline} $cmd'
+            tftpboot 0x$(printf %x ${cfg.loadAddress}) result/uimage ; tftpboot 0x$(printf %x $rootfsStart) result/rootfs ; tftpboot 0x$dtbStart result/dtb
+            bootm 0x$(printf %x ${cfg.loadAddress}) - 0x$dtbStart
             EOF
           '';
     };

modules/ubifs.nix

@@ -0,0 +1,50 @@
+{
+  config
+, pkgs
+, lib
+, ...
+}:
+let
+  inherit (lib) mkIf mkOption types;
+in
+{
+  imports = [
+    ./initramfs.nix
+  ];
+  options.hardware.ubi = {
+    minIOSize = mkOption { type = types.str; };
+    eraseBlockSize = mkOption { type = types.str; }; # LEB
+    maxLEBcount = mkOption { type = types.str; }; # LEB
+  };
+
+  config = mkIf (config.rootfsType == "ubifs") {
+    kernel.config = {
+      MTD_UBI="y";
+
+      UBIFS_FS = "y";
+      UBIFS_FS_SECURITY = "n";
+    };
+    boot.initramfs.enable = true;
+    system.outputs = rec {
+      systemConfiguration =
+        pkgs.systemconfig config.filesystem.contents;
+      rootfs =
+        let
+          inherit (pkgs.pkgsBuildBuild) runCommand mtdutils;
+          cfg = config.hardware.ubi;
+        in runCommand "mkfs.ubifs" {
+          depsBuildBuild = [ mtdutils ];
+        } ''
+          mkdir -p $TMPDIR/empty/nix/store/ $TMPDIR/empty/secrets $TMPDIR/empty/boot
+          cp ${systemConfiguration}/bin/activate $TMPDIR/empty/activate
+          ln -s ${pkgs.s6-init-bin}/bin/init $TMPDIR/empty/init
+          cp ${config.system.outputs.uimage} $TMPDIR/empty/boot/uimage
+          mkdir -p $TMPDIR/empty/nix/store
+          for path in $(cat ${systemConfiguration}/etc/nix-store-paths) ; do
+            (cd $TMPDIR/empty && cp -a $path .$path)
+          done
+          mkfs.ubifs -x favor_lzo -c ${cfg.maxLEBcount} -m ${cfg.minIOSize} -e ${cfg.eraseBlockSize}  -y -r $TMPDIR/empty --output $out  --squash-uids -o $out
+        '';
+    };
+  };
+}

modules/ubimage.nix

@@ -0,0 +1,112 @@
+{
+  config
+, pkgs
+, lib
+, ...
+}:
+let
+  inherit (lib) mkIf mkEnableOption mkOption types concatStringsSep;
+  loadaddr = config.boot.tftp.loadAddress;
+  cfg = config.boot.tftp;
+  instructions = pkgs.writeText "INSTALL.md" ''
+
+# First-time installation
+
+First-time installation of a UBIFS Liminix system presently can only
+be done from the U-Boot command line (or from a ramdisk-based recovery
+system: see "kexecboot" but we don't have detailed instructions for
+this process yet).
+
+These steps were tested on a Belkin RT3200 (also known as Linksys
+E8450).  Other devices may be set up differently, so use them as
+inspiration and don't just paste them blindly. Consult the Liminix
+manual for how to connect a serial cable to your device and get into
+U-Boot
+
+1) determine which MTD device is being used for UBI and the partition name:
+
+    uboot>  ubi part
+    Device 0: ubi0, MTD partition ubi
+
+In this case the important value is `ubi0`
+
+2) list the available volumes and create a new one on which to install Liminix
+
+    uboot> ubi info l
+    [ copious output scrolls past ]
+
+Expect there to be existing volumes and for some or all of them to be
+important. Unless you know what you're doing, don't remove anything
+whose name suggests it's related to uboot, or any kind of backup or
+recovery partition. To see how much space is free:
+
+    uboot> ubi info
+    [ ... ]
+    UBI: available PEBs:             823
+
+Now we can make our new root volume
+
+    uboot> ubi create liminix -
+
+3) transfer the root filesystem from the build system and write it
+to the new volume
+
+    uboot> setenv serverip ${cfg.serverip}
+    uboot> setenv ipaddr ${cfg.ipaddr}
+    uboot> tftpboot ${loadaddr} result/rootfs
+    uboot> ubi write ${loadaddr} liminix $filesize
+
+Now we have the root filesystem installed on the device. You
+can even mount it and poke around using `ubifsmount ubi0:liminix;
+ubifsls  /`
+
+4) optional: before you configure the device to boot into Liminix
+automatically, you can try booting it by hand to see if it works:
+
+    uboot> ubifsmount ubi0:liminix
+    uboot> ubifsload ${loadaddr} boot/uimage
+    uboot> bootm ${loadaddr}
+
+Once you've done this and you're happy with it, reset the device to
+U-Boot. You don't need to recreate the volume but you do need to
+repeat step 3.
+
+5) Instructions for configuring autoboot are likely to be very
+device-dependent. On the Linksys E8450/Belkin RT3200, the environment
+variable `boot_production` governs what happens on a normal boot, so
+you could do
+
+    uboot> setenv boot_production 'led $bootled_pwr on ; ubifsmount ubi0:liminix; ubifsload ${loadaddr} boot/uimage; bootm  ${loadaddr}'
+
+On other devices, some detective work may be needed. Try running
+`printenv` and look for likely commands, try looking at the existing
+boot process, maybe even try looking for documentation for that device.
+
+6) Now you can reboot the device into Liminix
+
+    uboot> reset
+
+'';
+in {
+  options.system.outputs = {
+    ubimage = mkOption {
+      type = types.package;
+      description = ''
+        UBIFS image and instructions to install it
+      '';
+    };
+  };
+
+  config = mkIf (config.rootfsType == "ubifs") {
+    system.outputs = {
+      ubimage =
+        let o = config.system.outputs; in
+        pkgs.runCommand "ubimage" {} ''
+          mkdir $out
+          cd $out
+          ln -s ${o.rootfs} rootfs
+          ln -s ${instructions} INSTALL
+       '';
+    };
+  };
+}

pkgs/kernel/default.nix

@@ -11,12 +11,7 @@
 let
   writeConfig = import ./write-kconfig.nix { inherit lib writeText; };
   kconfigFile = writeConfig "kconfig" config;
-  arch = if stdenv.isMips
-         then "mips"
-         else if stdenv.isAarch64
-         then "arm64"
-         else throw "unknown arch";
-
+  arch = stdenv.hostPlatform.linuxArch;
   inherit lib; in
 stdenv.mkDerivation rec {
   name = "kernel";
@@ -54,6 +49,7 @@ stdenv.mkDerivation rec {
 
   patches = [
     ./cmdline-cookie.patch
+    ./phram-allow-cached-mappings.patch
   ];
 
   # this is here to work around what I think is a bug in nixpkgs
@@ -81,7 +77,7 @@ stdenv.mkDerivation rec {
     export KBUILD_OUTPUT=`pwd`
     cp ${kconfigFile} .config
     cp ${kconfigFile} .config.orig
-    make V=1 olddefconfig
+    make olddefconfig
   '';
 
   checkConfigurationPhase = ''

pkgs/kernel/kernel_fdt.its

@@ -1,6 +1,6 @@
 /dts-v1/;
 
-//  used on aarch64 to provide a U-bootable image that combines
+//  used on arm/aarch64 to provide a U-bootable image that combines
 //  kernel and fdt
 
 / {
@@ -12,7 +12,7 @@
             description = "Vanilla Linux kernel";
             // data = /incbin/("./vmlinux.bin.gz");
             type = "kernel";
-            arch = "arm64";
+            // arch = "arm64";
             os = "linux";
             // compression = "gzip";
             // load = <00000000>;
@@ -28,7 +28,7 @@
             description = "Flattened Device Tree blob";
             // data = /incbin/("./target.dtb");
             type = "flat_dt";
-            arch = "arm64";
+            // arch = "arm64";
             compression = "none";
             hash-1 {
                     algo = "crc32";

pkgs/kernel/phram-allow-cached-mappings.patch

@@ -0,0 +1,47 @@
+From bb7e7aeb3d832059e33b1e76eb85d4680f77abf2 Mon Sep 17 00:00:00 2001
+From: Ben Hutchings <ben@decadent.org.uk>
+Date: Fri, 3 Jun 2016 01:08:36 +0100
+Subject: [PATCH] phram: Use memremap() to allow mapping of system RAM
+
+Using memremap() instead of ioremap() allows mapping a disk image in
+system RAM that has somehow been reserved.  It should fall back
+to ioremap() where necessary.
+
+Entirely untested, and I'm not convinced this is a good idea at all.
+---
+ drivers/mtd/devices/phram.c | 7 ++++---
+ 1 file changed, 4 insertions(+), 3 deletions(-)
+
+diff --git a/drivers/mtd/devices/phram.c b/drivers/mtd/devices/phram.c
+index 8b66e52ca3cc..0ea254e2ba51 100644
+--- a/drivers/mtd/devices/phram.c
++++ b/drivers/mtd/devices/phram.c
+@@ -88,7 +88,7 @@ static void unregister_devices(void)
+ 
+ 	list_for_each_entry_safe(this, safe, &phram_list, list) {
+ 		mtd_device_unregister(&this->mtd);
+-		iounmap(this->mtd.priv);
++		memunmap(this->mtd.priv);
+ 		kfree(this->mtd.name);
+ 		kfree(this);
+ 	}
+@@ -104,7 +104,8 @@ static int register_device(char *name, phys_addr_t start, size_t len)
+ 		goto out0;
+ 
+ 	ret = -EIO;
+-	new->mtd.priv = ioremap(start, len);
++	new->mtd.priv = memremap(start, len,
++				 MEMREMAP_WB | MEMREMAP_WT | MEMREMAP_WC);
+ 	if (!new->mtd.priv) {
+ 		pr_err("ioremap failed\n");
+ 		goto out1;
+@@ -134,7 +135,7 @@ static int register_device(char *name, phys_addr_t start, size_t len)
+ 	return 0;
+ 
+ out2:
+-	iounmap(new->mtd.priv);
++	memunmap(new->mtd.priv);
+ out1:
+ 	kfree(new);
+ out0:
+

pkgs/kernel/uimage.nix

@@ -7,21 +7,27 @@
 } :
 let
   objcopy = "${stdenv.cc.bintools.targetPrefix}objcopy";
+  arch = stdenv.hostPlatform.linuxArch;
+  stripAndZip = ''
+    ${objcopy} -O binary -R .reginfo -R .notes -R .note -R .comment -R .mdebug -R .note.gnu.build-id -S vmlinux.elf vmlinux.bin
+    rm -f vmlinux.bin.lzma ; lzma -k -z  vmlinux.bin
+  '';
 in {
   kernel
 , commandLine
 , entryPoint
 , extraName ? ""                # e.g. socFamily
 , loadAddress
+, imageFormat
 , dtb ? null
-} :
-stdenv.mkDerivation {
+} : stdenv.mkDerivation {
   name = "kernel.image";
   phases = [
     "preparePhase"
-    (if dtb != null then "dtbPhase" else ":")
-    "buildPhase"
-    "installPhase" ];
+    (if commandLine != null then assert dtb != null; "mungeDtbPhase" else ":")
+    (if imageFormat == "fit" then "buildPhaseFIT" else "buildPhaseUImage")
+    "installPhase"
+  ];
   nativeBuildInputs = [
     lzma
     dtc
@@ -31,35 +37,43 @@ stdenv.mkDerivation {
   preparePhase = ''
     cp ${kernel} vmlinux.elf; chmod +w vmlinux.elf
   '';
-  dtbPhase = ''
+  mungeDtbPhase = ''
     dtc -I dtb -O dts -o tmp.dts ${dtb}
     echo '/{ chosen { bootargs = ${builtins.toJSON commandLine}; }; };'  >> tmp.dts
     dtc -I dts -O dtb -o tmp.dtb tmp.dts
   '';
 
-  buildPhase =
-    let arch =
-          # per output of "mkimage -A list". I *think* these
-          # are the same as the kernel arch convention, but
-          # maybe that's coincidence
-          if stdenv.isMips
-          then "mips"
-          else if stdenv.isAarch64
-          then "arm64"
-          else throw "unknown arch";
-    in ''
-      ${objcopy} -O binary -R .reginfo -R .notes -R .note -R .comment -R .mdebug -R .note.gnu.build-id -S vmlinux.elf vmlinux.bin
-      rm -f vmlinux.bin.lzma ; lzma -k -z  vmlinux.bin
-      cat ${./kernel_fdt.its} > mkimage.its
-      echo '/ { images { kernel { data = /incbin/("./vmlinux.bin.lzma"); }; }; };' >> mkimage.its
-      echo '/ { images { kernel { load = <${loadAddress}>; }; }; };' >> mkimage.its
-      echo '/ { images { kernel { entry = <${entryPoint}>; }; }; };' >> mkimage.its
-      echo '/ { images { kernel { compression = "lzma"; }; }; };' >> mkimage.its
-      echo '/ { images { fdt-1 { data = /incbin/("./tmp.dtb"); }; }; }; ' >> mkimage.its
-      mkimage -f mkimage.its mkimage.itb
-      mkimage -l mkimage.itb
-    '';
+  buildPhaseUImage = ''
+    test -f tmp.dtb && ${objcopy} --update-section .appended_dtb=tmp.dtb vmlinux.elf || ${objcopy} --add-section .appended_dtb=tmp.dtb vmlinux.elf
+    ${stripAndZip}
+    mkimage -A ${arch} -O linux -T kernel -C lzma -a ${loadAddress} -e ${entryPoint} -n '${lib.toUpper arch} Liminix Linux ${extraName}' -d vmlinux.bin.lzma kernel.uimage
+  '';
+
+  buildPhaseFIT = ''
+    ${stripAndZip}
+    cat ${./kernel_fdt.its} > mkimage.its
+    cat << _VARS  >> mkimage.its
+    / {
+        images {
+            kernel {
+                data = /incbin/("./vmlinux.bin.lzma");
+                load = <${loadAddress}>;
+                entry = <${entryPoint}>;
+                arch = "${arch}";
+                compression = "lzma";
+            };
+            fdt-1 {
+                data = /incbin/("./tmp.dtb");
+                arch = "${arch}";
+            };
+        };
+    };
+    _VARS
+    mkimage -f mkimage.its kernel.uimage
+    mkimage -l kernel.uimage
+  '';
+
   installPhase = ''
-    cp mkimage.itb $out
+    cp kernel.uimage $out
   '';
 }

pkgs/openwrt/default.nix

@@ -34,4 +34,5 @@ in {
   applyPatches.ath79 = doPatch "ath79";
   applyPatches.ramips = doPatch "ramips";
   applyPatches.mediatek = doPatch "mediatek"; # aarch64
+  applyPatches.mvebu = doPatch "mvebu"; # arm
 }

pkgs/preinit/Makefile

@@ -0,0 +1,4 @@
+CFLAGS+=-Os -fno-stack-protector -fpic -fPIC
+LDFLAGS=-static
+
+preinit: preinit.o parseopts.o

pkgs/preinit/default.nix

@@ -15,7 +15,6 @@ stdenv.mkDerivation {
 
 #  NIX_DEBUG=2;
   hardeningDisable = [ "all" ];
-  CFLAGS = "-Os -static -DPREINIT_USE_LIBC  -fno-stack-protector -fpic -fPIC -I ./ -I ${kernel}/tools/include/nolibc";
 
   postBuild = ''
     $STRIP  --remove-section=.note --remove-section=.comment preinit

pkgs/preinit/parseopts.c

@@ -0,0 +1,97 @@
+#include <string.h>
+#include <unistd.h>
+
+static int begins_with(char * str, char * prefix)
+{
+	while(*prefix) {
+		if(*str == '\0') return 0;
+		if(*str != *prefix) return 0;
+		str++;
+		prefix++;
+	}
+	return 1;
+}
+
+
+void parseopts(char * cmdline, char **root, char **rootfstype) {
+    *root = 0;
+    *rootfstype = 0;
+
+    for(char *p = cmdline; *p; p++) {
+	if(begins_with(p, "root=")) {
+	    *root = p + strlen("root=");
+	    while(*p && (*p != ' ')) p++;
+	    
+	    if(*p) {
+		*p = '\0';
+		p++;
+	    };
+	};
+	if(begins_with(p, "rootfstype=")) {
+	    *rootfstype = p + strlen("rootfstype=");
+	    while(*p && (*p != ' ')) p++;
+	    if(*p) {
+		*p = '\0';
+		p++;
+	    };
+	};
+    };
+}
+
+#ifdef TESTS
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#define die(fmt, ...) do { printf(fmt, __VA_ARGS__); exit(1); } while(0)
+#define S(x) #x
+#define expect_equal(actual, expected) \
+    if(!actual || strcmp(actual, expected)) die("%d: expected \"%s\", got \"%s\"", __LINE__, expected, actual);
+
+
+int main()
+{
+    char * root = "/dev/hda1";
+    char * rootfstype = "xiafs";
+    char *buf;
+
+    // finds root= and rootfstype= options
+    buf = strdup("liminix console=ttyS0,115200 panic=10 oops=panic init=/bin/init loglevel=8 root=/dev/ubi0_4 rootfstype=ubifs fw_devlink=off mtdparts=phram0:18M(rootfs) phram.phram=phram0,0x40400000,18874368,65536 root=/dev/mtdblock0 foo");
+    parseopts(buf, &root, &rootfstype);
+    expect_equal(root, "/dev/mtdblock0");
+    expect_equal(rootfstype, "ubifs");
+
+    // in case of duplicates, chooses the latter
+    // also: works if the option is end of string
+    buf = strdup("liminix console=ttyS0,115200 panic=10 oops=panic init=/bin/init loglevel=8 root=/dev/ubi0_4 rootfstype=ubifs fw_devlink=off mtdparts=phram0:18M(rootfs) phram.phram=phram0,0x40400000,18874368,65536 root=/dev/mtdblock0");
+    parseopts(buf, &root, &rootfstype);
+    expect_equal(root, "/dev/mtdblock0");
+    expect_equal(rootfstype, "ubifs");
+
+    // options may appear in either order
+    buf = strdup("liminix fw_devlink=off root=/dev/hda1 rootfstype=ubifs  foo");
+    parseopts(buf, &root, &rootfstype);
+    expect_equal(root, "/dev/hda1");
+    expect_equal(rootfstype, "ubifs");
+
+    buf = strdup("liminix rootfstype=ubifs fw_devlink=off root=/dev/hda1 foo");
+    parseopts(buf, &root, &rootfstype);
+    expect_equal(rootfstype, "ubifs");
+    expect_equal(root, "/dev/hda1");
+
+    // provides NULL for missing options
+    buf = strdup("liminix rufustype=ubifs fw_devlink=off foot=/dev/hda1");
+    parseopts(buf, &root, &rootfstype);
+    if(rootfstype) die("expected null rootfstype, got \"%s\"", rootfstype);
+    if(root) die("expected null root, got \"%s\"", root);
+
+    // provides empty strings for empty options
+    buf = strdup("liminix rootfstype= fw_devlink=off root= /dev/hda1");
+    parseopts(buf, &root, &rootfstype);
+    if(strlen(rootfstype)) die("expected empty rootfstype, got \"%s\"", rootfstype);
+    if(strlen(root)) die("expected null root, got \"%s\"", root);
+
+}
+
+
+#endif

pkgs/preinit/preinit.c

@@ -1,37 +1,36 @@
-#ifdef PREINIT_USE_LIBC
 #include <string.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <sys/mount.h>
 #include <sys/wait.h>
 #include <string.h>
-#else
-#include <nolibc.h>
-#endif
-#include <asm/setup.h>
+
+#include <asm/setup.h>		/* for COMMAND_LINE_SIZE */
+
+void parseopts(char * cmdline, char **root, char **rootfstype);
 
 #define ERR(x) write(2, x, strlen(x))
 #define AVER(c) do { if(c < 0) ERR("failed: "  #c); } while(0)
 
 static int begins_with(char * str, char * prefix)
 {
-	while(*prefix) {
-		if(*str == '\0') return 0;
-		if(*str != *prefix) return 0;
-		str++;
-		prefix++;
-	}
-	return 1;
+    while(*prefix) {
+	if(*str == '\0') return 0;
+	if(*str != *prefix) return 0;
+	str++;
+	prefix++;
+    }
+    return 1;
 }
 
-static void fork_exec(char * command, char *args[])
+static int fork_exec(char * command, char *args[])
 {
-	int fork_pid = fork();
-	AVER(fork_pid);
-	if(fork_pid > 0)
-		wait(NULL);
-	else
-		AVER(execve(command, args, NULL));
+    int fork_pid = fork();
+    AVER(fork_pid);
+    if(fork_pid > 0)
+	wait(NULL);
+    else
+	return execve(command, args, NULL);
 }
 
 char banner[]  = "Running pre-init...\n";
@@ -39,52 +38,45 @@ char buf[COMMAND_LINE_SIZE];
 
 int main(int argc, char *argv[], char *envp[])
 {
-#ifndef PREINIT_USE_LIBC
-        asm("la $gp, _gp\nsw $gp,16($sp)");
-#endif	
-	char *rootdevice = 0;
-	char *p = buf;
-	write(1, banner, strlen(banner));
+    char *rootdevice = 0;
+    char *rootfstype = 0;
+    char *p = buf;
+    write(1, banner, strlen(banner));
 
-	mount("none", "/proc", "proc", 0, NULL);
+    mount("none", "/proc", "proc", 0, NULL);
 
-	int cmdline = open("/proc/cmdline", O_RDONLY, 0);
+    int cmdline = open("/proc/cmdline", O_RDONLY, 0);
 
-	if(cmdline>=0) {
-		int len = read(cmdline, buf, sizeof buf - 1);
-		buf[len]='\0';
-		write(1, "cmdline ", 8);
-		write(1, buf, len);
-	};
+    if(cmdline>=0) {
+	int len = read(cmdline, buf, sizeof buf - 1);
+	buf[len]='\0';
+	write(1, "cmdline ", 8);
+	write(1, buf, len);
+    };
 
-	while(*p) {
-		if(begins_with(p, "root=")) {
-			rootdevice = p + 5;
-			while(*p && (*p != ' ')) p++;
-			*p= '\0';
-		}
-		while(*p && (*p != ' ')) p++;
-		p++;
-	}
+    parseopts(buf, &rootdevice, &rootfstype);
+	
+    if(rootdevice) {
+	if(!rootfstype) rootfstype = "jffs2"; /* backward compatibility */
+	write(1, "rootdevice ", 11);
+	write(1, rootdevice, strlen(rootdevice));
+	write(1, " (", 2);
+	write(1, rootfstype, strlen(rootfstype));
+	write(1, ")\n", 1);
 
-	if(rootdevice) {
-		write(1, "rootdevice ", 11);
-		write(1, rootdevice, strlen(rootdevice));
-		write(1, "\n", 1);
+	AVER(mount(rootdevice, "/target/persist", rootfstype, 0, NULL));
+	AVER(mount("/target/persist/nix", "/target/nix",
+		   "bind", MS_BIND, NULL));
 
-		AVER(mount(rootdevice, "/target/persist", "jffs2", 0, NULL));
-		AVER(mount("/target/persist/nix", "/target/nix",
-			   "bind", MS_BIND, NULL));
+	char *exec_args[] = { "activate",  "/target", NULL };
+	AVER(fork_exec("/target/persist/activate", exec_args));
+	AVER(chdir("/target"));
 
-		char *exec_args[] = { "activate",  "/target", NULL };
-		fork_exec("/target/persist/activate", exec_args);
-		AVER(chdir("/target"));
+	AVER(mount("/target", "/", "bind", MS_BIND | MS_REC, NULL));
+	AVER(chroot(".")); 
 
-		AVER(mount("/target", "/", "bind", MS_BIND | MS_REC, NULL));
-		AVER(chroot(".")); 
-		argv[0] = "init";
-		argv[1] = NULL;
-
-		AVER(execve("/persist/init", argv, envp));
-	}
+	argv[0] = "init";
+	argv[1] = NULL;
+	AVER(execve("/persist/init", argv, envp));
+    }
 }

pkgs/preinit/shell.nix

@@ -0,0 +1,5 @@
+with import <nixpkgs> {};
+mkShell {
+  name = "preinit-env";
+  src = ./.;
+}

pkgs/systemconfig/default.nix

@@ -68,7 +68,7 @@ in attrset:
     src = ./.;
 
     CFLAGS = "-Os";
-    LDFLAGS  = "-static";
+    LDFLAGS  = "-static -Xlinker -static";
 
     postConfigure = ''
       cp ${makedevs} makedevs.c

pkgs/tufted/tftp.lua

@@ -195,19 +195,22 @@ function tftp:handle_RRQ(socket, host, port, source, options)
                 ]]
                 yield(false, true)
             end
-            socket:sendto(self.DATA(data, tid), host, port)
-            --[[  Now check for an ACK.
-                RFC1350 requires that for every packet sent, an ACK is received
-                before the next packet can be sent.
-            ]]
+
             local acked
             local retried = 0
             local timeout = time() + timeout_secs
             local timedout = false
             repeat
+                socket:sendto(self.DATA(data, tid), host, port)
+                --[[  Now check for an ACK.
+                   RFC1350 requires that for every packet sent, an ACK is received
+                   before the next packet can be sent.
+                ]]
                 yield(true, false) -- we need to wait until the socket is readable again
                 local ack, ackhost, ackport = socket:recvfrom(ACKSIZE)
-                if ackhost ~= host or ackport ~= port or self.parse_ACK(ack) ~= tid then
+                local ack_sequence = self.parse_ACK(ack)
+
+                if ackhost ~= host or ackport ~= port then
                    --[[https://tools.ietf.org/html/rfc1350#page-5
                        "If a source TID does not match, the packet should be
                        discarded as erroneously sent from somewhere else.
@@ -216,13 +219,21 @@ function tftp:handle_RRQ(socket, host, port, source, options)
                    ]]
                    socket:sendto(err(ERR_UNKNOWN_ID), ackhost, ackport)
                    yield(true, false)
-                else
-                    acked = true
-                end
+		elseif ack_sequence ~= tid then
+		   -- this looks confusing, but the local variable
+		   -- "tid" here is actually block number (aka
+		   -- sequence number), not tid at all.
+		   log(("ack received for old block %d (expecting %d)"):format(ack_sequence, tid))
+		   acked = false
+		else
+		   acked = true
+		end
+
+		if not acked then log("resending") end
                 retried = retried + 1
                 timedout = time() > timeout
-            until acked or retried > ACK_RETRIES or timedout
-            if timedout or retried > ACK_RETRIES then
+            until acked or retried > ACK_RETRIES
+            if retried > ACK_RETRIES then
                 --There doesn't seem to be a standard error for timeout.
                 socket:sendto(err("Ack timeout"), host, port)
                 error("Timeout waiting for ACK")