move all output modules to subdirectory, trash standard.nix

standard.nix isn't, is the essence here. Not all devices support flashimage as it is currently defined - some have diskimage, some have neither
2023-12-10 15:23:12 +00:00
parent 53fed8839a
commit c81e7c4d35
12 changed files with 28 additions and 20 deletions
--- a/modules/outputs/tftpboot.nix
+++ b/modules/outputs/tftpboot.nix
@@ -0,0 +1,98 @@
+{
+  config
+, pkgs
+, lib
+, ...
+}:
+let
+  inherit (lib) mkOption types concatStringsSep;
+  cfg = config.boot.tftp;
+in {
+  imports = [ ../ramdisk.nix ];
+  options.boot.tftp.freeSpaceBytes = mkOption {
+    type = types.int;
+    default = 0;
+  };
+  options.system.outputs = {
+    tftpboot = mkOption {
+      type = types.package;
+      description = ''
+        tftpboot
+        ********
+
+        This output is intended for developing on a new device.
+        It assumes you have a serial connection and a
+        network connection to the device and that your
+        build machine is running a TFTP server.
+
+        The output is a directory containing kernel and
+        root filesystem image, and a script :file:`boot.scr` of U-Boot
+        commands that will load the images into memory and
+        run them directly,
+        instead of first writing them to flash. This saves
+        time and erase cycles.
+
+        It uses the Linux `phram <https://github.com/torvalds/linux/blob/master/drivers/mtd/devices/phram.c>`_ driver to emulate a flash device using a segment of physical RAM.
+      '';
+    };
+    boot-scr = mkOption {
+      type = types.package;
+      internal = true;
+      description = ''
+        U-Boot commands to load and boot a kernel and rootfs over TFTP.
+        Copy-paste into the device boot monitor
+      '';
+    };
+  };
+  config = {
+    boot.ramdisk.enable = true;
+
+    system.outputs = rec {
+      tftpboot =
+        let o = config.system.outputs; in
+        pkgs.runCommand "tftpboot" {} ''
+          mkdir $out
+          cd $out
+          ln -s ${o.rootfs} rootfs
+          ln -s ${o.kernel} vmlinux
+          ln -s ${o.manifest} manifest
+          ln -s ${o.kernel.headers} build
+          ln -s ${o.uimage} uimage
+          ln -s ${o.boot-scr}/dtb dtb
+          ln -s ${o.boot-scr}/script boot.scr
+       '';
+
+      boot-scr =
+        let
+          inherit (pkgs.lib.trivial) toHexString;
+          o = config.system.outputs;
+          cmdline = concatStringsSep " " config.boot.commandLine;
+        in
+          pkgs.buildPackages.runCommand "boot-scr" { nativeBuildInputs = [ pkgs.pkgsBuildBuild.dtc ];  } ''
+            uimageSize=$(($(stat -L -c %s ${o.uimage}) + 0x1000 &(~0xfff)))
+            rootfsStart=0x$(printf %x $((${toString cfg.loadAddress} + 0x100000 + $uimageSize   &(~0xfffff) )))
+            rootfsBytes=$(($(stat -L -c %s ${o.rootfs}) + 0x100000 &(~0xfffff)))
+            rootfsBytes=$(($rootfsBytes + ${toString cfg.freeSpaceBytes} ))
+            rootfsMb=$(($rootfsBytes >> 20))
+            cmd="mtdparts=phram0:''${rootfsMb}M(rootfs) phram.phram=phram0,''${rootfsStart},''${rootfsBytes},${toString config.hardware.flash.eraseBlockSize} root=/dev/mtdblock0";
+
+            dtbStart=$(printf %x $((${toString 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 ${cmdline} $cmd'
+            tftpboot 0x${lib.toHexString cfg.loadAddress} result/uimage ; tftpboot 0x$(printf %x $rootfsStart) result/rootfs ; tftpboot 0x$dtbStart result/dtb
+            bootm 0x${lib.toHexString cfg.loadAddress} - 0x$dtbStart
+            EOF
+          '';
+    };
+  };
+}