Simplified much more the expressions for cross building and multiplatform.

I introduce the new nixpkgs parameter "platform", defaulting to "pc",
which was before defined as an attribute of nixpkgs.

I made the crossSystem nixpkgs attribute set parameter contain its own 'platform'.

This allows cross-building a kernel for a given crossSystem.platform in a non-PC
platform.

The actual native platform can be taken from stdenv.platform, and this way we also
avoid the constant passing of 'platform' to packages for platform-dependant builds
(kernel, initrd, ...).

I will update nixos accordingly to these changes, for non-PC platforms to work.

I think we are gaining on flexibility and clearness. I could cross build succesfully
an ultrasparc kernel and a mipsel kernel on PC. But since this change, I should be able
to do this also in non-PC.

Before this change, there was no possibility of distinguishing the "target platform" or
the "native build platform" when cross building, being the single "platform" attribute
always interpreted as target platform.

The platform is a quite relevant attribute set, as it determines the linuxHeaders used
(in the case, by now the only one supported, of linux targets).

The platform attributes are quite linux centric still. Let's hope for more generality to come.

svn path=/nixpkgs/trunk/; revision=20273

5 files changed, 437 insertions, 408 deletions

diff --git a/pkgs/build-support/kernel/make-initrd.nix b/pkgs/build-support/kernel/make-initrd.nix
index 9626857769621..f2cf894b86301 100644
--- a/pkgs/build-support/kernel/make-initrd.nix
+++ b/pkgs/build-support/kernel/make-initrd.nix
@@ -12,15 +12,19 @@
 # `contents = {object = ...; symlink = /init;}' is a typical
 # argument.
 
-{stdenv, perl, cpio, contents, platform}:
+{stdenv, perl, cpio, contents, ubootChooser}:
 
+let
+  inputsFun = ubootName : [perl cpio]
+    ++ stdenv.lib.optional (ubootName != null) [ ubootChooser ubootName ];
+  makeUInitrdFun = ubootName : (ubootName != null);
+in
 stdenv.mkDerivation {
   name = "initrd";
   builder = ./make-initrd.sh;
-  buildInputs = [perl cpio]
-    ++ stdenv.lib.optional (platform.uboot != null) [ platform.uboot ];
+  buildNativeInputs = inputsFun stdenv.platform.uboot;
 
-  makeUInitrd = if (platform.uboot != null) then true else false;
+  makeUInitrd = makeUInitrdFun stdenv.platform.uboot;
 
   # !!! should use XML.
   objects = map (x: x.object) contents;
@@ -31,4 +35,9 @@ stdenv.mkDerivation {
   exportReferencesGraph =
     map (x: [("closure-" + baseNameOf x.symlink) x.object]) contents;
   pathsFromGraph = ./paths-from-graph.pl;
+
+  crossAttrs = {
+    buildNativeInputs = inputsFun stdenv.cross.platform.uboot;
+    makeUInitrd = makeUInitrdFun stdenv.cross.platform.uboot;
+  };
 }
diff --git a/pkgs/os-specific/linux/kernel/linux-2.6.32.nix b/pkgs/os-specific/linux/kernel/linux-2.6.32.nix
index 30d2d3700536a..062c5256399a5 100644
--- a/pkgs/os-specific/linux/kernel/linux-2.6.32.nix
+++ b/pkgs/os-specific/linux/kernel/linux-2.6.32.nix
@@ -1,6 +1,201 @@
-args @ { stdenv, fetchurl, platform, userModeLinux ? false, extraConfig ? ""
+args @ { stdenv, fetchurl, userModeLinux ? false, extraConfig ? ""
 , ... }:
 
+let
+  configWithPlatform = kernelPlatform :
+    ''
+      # Don't include any debug features.
+      DEBUG_KERNEL n
+
+      # Support drivers that need external firmware.
+      STANDALONE n
+
+      # Make /proc/config.gz available.
+      IKCONFIG_PROC y
+
+      # Optimize with -O2, not -Os.
+      CC_OPTIMIZE_FOR_SIZE n
+
+      # Enable the kernel's built-in memory tester.
+      MEMTEST y
+
+      # Include the CFQ I/O scheduler in the kernel, rather than as a
+      # module, so that the initrd gets a good I/O scheduler.
+      IOSCHED_CFQ y
+
+      # Disable some expensive (?) features.
+      FTRACE n
+      KPROBES n
+      NUMA? n
+      PM_TRACE_RTC n
+
+      # Enable various subsystems.
+      ACCESSIBILITY y # Accessibility support
+      AUXDISPLAY y # Auxiliary Display support
+      DONGLE y # Serial dongle support
+      HIPPI y
+      MTD_COMPLEX_MAPPINGS y # needed for many devices
+      NET_POCKET y # enable pocket and portable adapters
+      SCSI_LOWLEVEL y # enable lots of SCSI devices
+      SCSI_LOWLEVEL_PCMCIA y
+      SPI y # needed for many devices
+      SPI_MASTER y
+      WAN y
+
+      # Networking options.
+      IP_PNP n
+      IPV6_PRIVACY y
+      NETFILTER_ADVANCED y
+      IP_VS_PROTO_TCP y
+      IP_VS_PROTO_UDP y
+      IP_VS_PROTO_ESP y
+      IP_VS_PROTO_AH y
+      IP_DCCP_CCID3 n # experimental
+      CLS_U32_PERF y
+      CLS_U32_MARK y
+
+      # Wireless networking.
+      IPW2100_MONITOR y # support promiscuous mode
+      IPW2200_MONITOR y # support promiscuous mode
+      IWLWIFI_LEDS? y
+      IWLWIFI_SPECTRUM_MEASUREMENT y
+      IWL3945_SPECTRUM_MEASUREMENT y
+      IWL4965 y # Intel Wireless WiFi 4965AGN
+      IWL5000 y # Intel Wireless WiFi 5000AGN
+      HOSTAP_FIRMWARE y # Support downloading firmware images with Host AP driver
+      HOSTAP_FIRMWARE_NVRAM y
+
+      # Some settings to make sure that fbcondecor works - in particular,
+      # disable tileblitting and the drivers that need it.
+
+      # Enable various FB devices.
+      FB y
+      FB_EFI y
+      FB_NVIDIA_I2C y # Enable DDC Support
+      FB_RIVA_I2C y
+      FB_ATY_CT y # Mach64 CT/VT/GT/LT (incl. 3D RAGE) support
+      FB_ATY_GX y # Mach64 GX support
+      FB_SAVAGE_I2C y
+      FB_SAVAGE_ACCEL y
+      FB_SIS_300 y
+      FB_SIS_315 y
+      FB_3DFX_ACCEL y
+      FB_GEODE y
+
+      # Video configuration
+      # The intel drivers already require KMS
+      DRM_I915_KMS y
+
+      # Sound.
+      SND_AC97_POWER_SAVE y # AC97 Power-Saving Mode
+      SND_HDA_INPUT_BEEP y # Support digital beep via input layer
+      SND_USB_CAIAQ_INPUT y
+      PSS_MIXER y # Enable PSS mixer (Beethoven ADSP-16 and other compatible)
+
+      # USB serial devices.
+      USB_SERIAL_GENERIC y # USB Generic Serial Driver
+      USB_SERIAL_KEYSPAN_MPR y # include firmware for various USB serial devices
+      USB_SERIAL_KEYSPAN_USA28 y
+      USB_SERIAL_KEYSPAN_USA28X y
+      USB_SERIAL_KEYSPAN_USA28XA y
+      USB_SERIAL_KEYSPAN_USA28XB y
+      USB_SERIAL_KEYSPAN_USA19 y
+      USB_SERIAL_KEYSPAN_USA18X y
+      USB_SERIAL_KEYSPAN_USA19W y
+      USB_SERIAL_KEYSPAN_USA19QW y
+      USB_SERIAL_KEYSPAN_USA19QI y
+      USB_SERIAL_KEYSPAN_USA49W y
+      USB_SERIAL_KEYSPAN_USA49WLC y
+
+      # Filesystem options - in particular, enable extended attributes and
+      # ACLs for all filesystems that support them.
+      EXT2_FS_XATTR y # Ext2 extended attributes
+      EXT2_FS_POSIX_ACL y # Ext2 POSIX Access Control Lists
+      EXT2_FS_SECURITY y # Ext2 Security Labels
+      EXT2_FS_XIP y # Ext2 execute in place support
+      EXT4_FS_POSIX_ACL y
+      EXT4_FS_SECURITY y
+      REISERFS_FS_XATTR y
+      REISERFS_FS_POSIX_ACL y
+      REISERFS_FS_SECURITY y
+      JFS_POSIX_ACL y
+      JFS_SECURITY y
+      XFS_QUOTA y
+      XFS_POSIX_ACL y
+      XFS_RT y # XFS Realtime subvolume support
+      OCFS2_DEBUG_MASKLOG n
+      OCFS2_FS_POSIX_ACL y
+      BTRFS_FS_POSIX_ACL y
+      UBIFS_FS_XATTR y
+      UBIFS_FS_ADVANCED_COMPR y
+      NFSD_V2_ACL y
+      NFSD_V3 y
+      NFSD_V3_ACL y
+      NFSD_V4 y
+      CIFS_XATTR y
+      CIFS_POSIX y
+
+      # Security related features.
+      STRICT_DEVMEM y # Filter access to /dev/mem
+      SECURITY_SELINUX_BOOTPARAM_VALUE 0 # disable SELinux by default
+
+      # Misc. options.
+      8139TOO_8129 y
+      8139TOO_PIO n # PIO is slower
+      AIC79XX_DEBUG_ENABLE n
+      AIC7XXX_DEBUG_ENABLE n
+      AIC94XX_DEBUG n
+      B43_PCMCIA y
+      BLK_DEV_BSG n
+      BLK_DEV_CMD640_ENHANCED y # CMD640 enhanced support
+      BLK_DEV_IDEACPI y # IDE ACPI support
+      BLK_DEV_INTEGRITY y
+      BSD_PROCESS_ACCT_V3 y
+      BT_HCIUART_BCSP y
+      BT_HCIUART_H4 y # UART (H4) protocol support
+      BT_HCIUART_LL y
+      BT_RFCOMM_TTY y # RFCOMM TTY support
+      CPU_FREQ_DEBUG n
+      CRASH_DUMP n
+      DMAR? n # experimental
+      DVB_DYNAMIC_MINORS y # we use udev
+      FUSION y # Fusion MPT device support
+      IDE_GD_ATAPI y # ATAPI floppy support
+      IRDA_ULTRA y # Ultra (connectionless) protocol
+      JOYSTICK_IFORCE_232 y # I-Force Serial joysticks and wheels
+      JOYSTICK_IFORCE_USB y # I-Force USB joysticks and wheels
+      JOYSTICK_XPAD_FF y # X-Box gamepad rumble support
+      JOYSTICK_XPAD_LEDS y # LED Support for Xbox360 controller 'BigX' LED
+      KALLSYMS_EXTRA_PASS n
+      LDM_PARTITION y # Windows Logical Disk Manager (Dynamic Disk) support
+      LEDS_TRIGGER_IDE_DISK y # LED IDE Disk Trigger
+      LOGIRUMBLEPAD2_FF y # Logitech Rumblepad 2 force feedback
+      LOGO n # not needed
+      MEDIA_ATTACH y
+      MEGARAID_NEWGEN y
+      MICROCODE_AMD y
+      MODVERSIONS y
+      MOUSE_PS2_ELANTECH y # Elantech PS/2 protocol extension
+      MTRR_SANITIZER y
+      NET_FC y # Fibre Channel driver support
+      PCI_LEGACY y
+      PPP_MULTILINK y # PPP multilink support
+      REGULATOR y # Voltage and Current Regulator Support
+      SCSI_LOGGING y # SCSI logging facility
+      SERIAL_8250 y # 8250/16550 and compatible serial support
+      SLIP_COMPRESSED y # CSLIP compressed headers
+      SLIP_SMART y
+      THERMAL_HWMON y # Hardware monitoring support
+      USB_DEBUG n
+      USB_EHCI_ROOT_HUB_TT y # Root Hub Transaction Translators
+      X86_CHECK_BIOS_CORRUPTION y
+      X86_MCE y
+
+      ${if kernelPlatform ? kernelExtraConfig then kernelPlatform.kernelExtraConfig else ""}
+      ${extraConfig}
+    '';
+in
+
 import ./generic.nix (
 
   rec {
@@ -11,200 +206,16 @@ import ./generic.nix (
       sha256 = "1g6hs7j5kmifb3phbnckdmrnxd0cpqrijnnbry86z26npsh9my7l";
     };
 
-    features.iwlwifi = true;
+    config = configWithPlatform stdenv.platform;
+
+    platform = stdenv.platform;
 
-    config =
-      ''
-        # Don't include any debug features.
-        DEBUG_KERNEL n
-
-        # Support drivers that need external firmware.
-        STANDALONE n
-
-        # Make /proc/config.gz available.
-        IKCONFIG_PROC y
-
-        # Optimize with -O2, not -Os.
-        CC_OPTIMIZE_FOR_SIZE n
-
-        # Enable the kernel's built-in memory tester.
-        MEMTEST y
-
-        # Include the CFQ I/O scheduler in the kernel, rather than as a
-        # module, so that the initrd gets a good I/O scheduler.
-        IOSCHED_CFQ y
-
-        # Disable some expensive (?) features.
-        FTRACE n
-        KPROBES n
-        NUMA? n
-        PM_TRACE_RTC n
-
-        # Enable various subsystems.
-        ACCESSIBILITY y # Accessibility support
-        AUXDISPLAY y # Auxiliary Display support
-        DONGLE y # Serial dongle support
-        HIPPI y
-        MTD_COMPLEX_MAPPINGS y # needed for many devices
-        NET_POCKET y # enable pocket and portable adapters
-        SCSI_LOWLEVEL y # enable lots of SCSI devices
-        SCSI_LOWLEVEL_PCMCIA y
-        SPI y # needed for many devices
-        SPI_MASTER y
-        WAN y
-
-        # Networking options.
-        IP_PNP n
-        IPV6_PRIVACY y
-        NETFILTER_ADVANCED y
-        IP_VS_PROTO_TCP y
-        IP_VS_PROTO_UDP y
-        IP_VS_PROTO_ESP y
-        IP_VS_PROTO_AH y
-        IP_DCCP_CCID3 n # experimental
-        CLS_U32_PERF y
-        CLS_U32_MARK y
-
-        # Wireless networking.
-        IPW2100_MONITOR y # support promiscuous mode
-        IPW2200_MONITOR y # support promiscuous mode
-        IWLWIFI_LEDS? y
-        IWLWIFI_SPECTRUM_MEASUREMENT y
-        IWL3945_SPECTRUM_MEASUREMENT y
-        IWL4965 y # Intel Wireless WiFi 4965AGN
-        IWL5000 y # Intel Wireless WiFi 5000AGN
-        HOSTAP_FIRMWARE y # Support downloading firmware images with Host AP driver
-        HOSTAP_FIRMWARE_NVRAM y
-
-        # Some settings to make sure that fbcondecor works - in particular,
-        # disable tileblitting and the drivers that need it.
-
-        # Enable various FB devices.
-        FB y
-        FB_EFI y
-        FB_NVIDIA_I2C y # Enable DDC Support
-        FB_RIVA_I2C y
-        FB_ATY_CT y # Mach64 CT/VT/GT/LT (incl. 3D RAGE) support
-        FB_ATY_GX y # Mach64 GX support
-        FB_SAVAGE_I2C y
-        FB_SAVAGE_ACCEL y
-        FB_SIS_300 y
-        FB_SIS_315 y
-        FB_3DFX_ACCEL y
-        FB_GEODE y
-
-        # Video configuration
-        # The intel drivers already require KMS
-        DRM_I915_KMS y
-
-        # Sound.
-        SND_AC97_POWER_SAVE y # AC97 Power-Saving Mode
-        SND_HDA_INPUT_BEEP y # Support digital beep via input layer
-        SND_USB_CAIAQ_INPUT y
-        PSS_MIXER y # Enable PSS mixer (Beethoven ADSP-16 and other compatible)
-
-        # USB serial devices.
-        USB_SERIAL_GENERIC y # USB Generic Serial Driver
-        USB_SERIAL_KEYSPAN_MPR y # include firmware for various USB serial devices
-        USB_SERIAL_KEYSPAN_USA28 y
-        USB_SERIAL_KEYSPAN_USA28X y
-        USB_SERIAL_KEYSPAN_USA28XA y
-        USB_SERIAL_KEYSPAN_USA28XB y
-        USB_SERIAL_KEYSPAN_USA19 y
-        USB_SERIAL_KEYSPAN_USA18X y
-        USB_SERIAL_KEYSPAN_USA19W y
-        USB_SERIAL_KEYSPAN_USA19QW y
-        USB_SERIAL_KEYSPAN_USA19QI y
-        USB_SERIAL_KEYSPAN_USA49W y
-        USB_SERIAL_KEYSPAN_USA49WLC y
-
-        # Filesystem options - in particular, enable extended attributes and
-        # ACLs for all filesystems that support them.
-        EXT2_FS_XATTR y # Ext2 extended attributes
-        EXT2_FS_POSIX_ACL y # Ext2 POSIX Access Control Lists
-        EXT2_FS_SECURITY y # Ext2 Security Labels
-        EXT2_FS_XIP y # Ext2 execute in place support
-        EXT4_FS_POSIX_ACL y
-        EXT4_FS_SECURITY y
-        REISERFS_FS_XATTR y
-        REISERFS_FS_POSIX_ACL y
-        REISERFS_FS_SECURITY y
-        JFS_POSIX_ACL y
-        JFS_SECURITY y
-        XFS_QUOTA y
-        XFS_POSIX_ACL y
-        XFS_RT y # XFS Realtime subvolume support
-        OCFS2_DEBUG_MASKLOG n
-        OCFS2_FS_POSIX_ACL y
-        BTRFS_FS_POSIX_ACL y
-        UBIFS_FS_XATTR y
-        UBIFS_FS_ADVANCED_COMPR y
-        NFSD_V2_ACL y
-        NFSD_V3 y
-        NFSD_V3_ACL y
-        NFSD_V4 y
-        CIFS_XATTR y
-        CIFS_POSIX y
-
-        # Security related features.
-        STRICT_DEVMEM y # Filter access to /dev/mem
-        SECURITY_SELINUX_BOOTPARAM_VALUE 0 # disable SELinux by default
-
-        # Misc. options.
-        8139TOO_8129 y
-        8139TOO_PIO n # PIO is slower
-        AIC79XX_DEBUG_ENABLE n
-        AIC7XXX_DEBUG_ENABLE n
-        AIC94XX_DEBUG n
-        B43_PCMCIA y
-        BLK_DEV_BSG n
-        BLK_DEV_CMD640_ENHANCED y # CMD640 enhanced support
-        BLK_DEV_IDEACPI y # IDE ACPI support
-        BLK_DEV_INTEGRITY y
-        BSD_PROCESS_ACCT_V3 y
-        BT_HCIUART_BCSP y
-        BT_HCIUART_H4 y # UART (H4) protocol support
-        BT_HCIUART_LL y
-        BT_RFCOMM_TTY y # RFCOMM TTY support
-        CPU_FREQ_DEBUG n
-        CRASH_DUMP n
-        DMAR? n # experimental
-        DVB_DYNAMIC_MINORS y # we use udev
-        FUSION y # Fusion MPT device support
-        IDE_GD_ATAPI y # ATAPI floppy support
-        IRDA_ULTRA y # Ultra (connectionless) protocol
-        JOYSTICK_IFORCE_232 y # I-Force Serial joysticks and wheels
-        JOYSTICK_IFORCE_USB y # I-Force USB joysticks and wheels
-        JOYSTICK_XPAD_FF y # X-Box gamepad rumble support
-        JOYSTICK_XPAD_LEDS y # LED Support for Xbox360 controller 'BigX' LED
-        KALLSYMS_EXTRA_PASS n
-        LDM_PARTITION y # Windows Logical Disk Manager (Dynamic Disk) support
-        LEDS_TRIGGER_IDE_DISK y # LED IDE Disk Trigger
-        LOGIRUMBLEPAD2_FF y # Logitech Rumblepad 2 force feedback
-        LOGO n # not needed
-        MEDIA_ATTACH y
-        MEGARAID_NEWGEN y
-        MICROCODE_AMD y
-        MODVERSIONS y
-        MOUSE_PS2_ELANTECH y # Elantech PS/2 protocol extension
-        MTRR_SANITIZER y
-        NET_FC y # Fibre Channel driver support
-        PCI_LEGACY y
-        PPP_MULTILINK y # PPP multilink support
-        REGULATOR y # Voltage and Current Regulator Support
-        SCSI_LOGGING y # SCSI logging facility
-        SERIAL_8250 y # 8250/16550 and compatible serial support
-        SLIP_COMPRESSED y # CSLIP compressed headers
-        SLIP_SMART y
-        THERMAL_HWMON y # Hardware monitoring support
-        USB_DEBUG n
-        USB_EHCI_ROOT_HUB_TT y # Root Hub Transaction Translators
-        X86_CHECK_BIOS_CORRUPTION y
-        X86_MCE y
-
-        ${if platform ? kernelExtraConfig then platform.kernelExtraConfig else ""}
-        ${extraConfig}
-      '';
+    crossAttrs = {
+      config = configWithPlatform stdenv.cross.platform;
+      platform = stdenv.cross.platform;
+    };
+
+    features.iwlwifi = true;
   }
 
   // removeAttrs args ["extraConfig"]
diff --git a/pkgs/os-specific/linux/kernel/linux-2.6.33.nix b/pkgs/os-specific/linux/kernel/linux-2.6.33.nix
index 46eb32e1ca636..050ba98f740b5 100644
--- a/pkgs/os-specific/linux/kernel/linux-2.6.33.nix
+++ b/pkgs/os-specific/linux/kernel/linux-2.6.33.nix
@@ -1,6 +1,199 @@
-args @ { stdenv, fetchurl, platform, userModeLinux ? false, extraConfig ? ""
+args @ { stdenv, fetchurl, userModeLinux ? false, extraConfig ? ""
 , ... }:
 
+let
+  configWithPlatform = kernelPlatform :
+    ''
+      # Don't include any debug features.
+      DEBUG_KERNEL n
+
+      # Support drivers that need external firmware.
+      STANDALONE n
+
+      # Make /proc/config.gz available.
+      IKCONFIG_PROC y
+
+      # Optimize with -O2, not -Os.
+      CC_OPTIMIZE_FOR_SIZE n
+
+      # Enable the kernel's built-in memory tester.
+      MEMTEST y
+
+      # Include the CFQ I/O scheduler in the kernel, rather than as a
+      # module, so that the initrd gets a good I/O scheduler.
+      IOSCHED_CFQ y
+
+      # Disable some expensive (?) features.
+      FTRACE n
+      KPROBES n
+      NUMA? n
+      PM_TRACE_RTC n
+
+      # Enable various subsystems.
+      ACCESSIBILITY y # Accessibility support
+      AUXDISPLAY y # Auxiliary Display support
+      DONGLE y # Serial dongle support
+      HIPPI y
+      MTD_COMPLEX_MAPPINGS y # needed for many devices
+      NET_POCKET y # enable pocket and portable adapters
+      SCSI_LOWLEVEL y # enable lots of SCSI devices
+      SCSI_LOWLEVEL_PCMCIA y
+      SPI y # needed for many devices
+      SPI_MASTER y
+      WAN y
+
+      # Networking options.
+      IP_PNP n
+      IPV6_PRIVACY y
+      NETFILTER_ADVANCED y
+      IP_VS_PROTO_TCP y
+      IP_VS_PROTO_UDP y
+      IP_VS_PROTO_ESP y
+      IP_VS_PROTO_AH y
+      IP_DCCP_CCID3 n # experimental
+      CLS_U32_PERF y
+      CLS_U32_MARK y
+
+      # Wireless networking.
+      IPW2100_MONITOR y # support promiscuous mode
+      IPW2200_MONITOR y # support promiscuous mode
+      IWLWIFI_SPECTRUM_MEASUREMENT y
+      IWL3945_SPECTRUM_MEASUREMENT y
+      IWL4965 y # Intel Wireless WiFi 4965AGN
+      IWL5000 y # Intel Wireless WiFi 5000AGN
+      HOSTAP_FIRMWARE y # Support downloading firmware images with Host AP driver
+      HOSTAP_FIRMWARE_NVRAM y
+
+      # Some settings to make sure that fbcondecor works - in particular,
+      # disable tileblitting and the drivers that need it.
+
+      # Enable various FB devices.
+      FB y
+      FB_EFI y
+      FB_NVIDIA_I2C y # Enable DDC Support
+      FB_RIVA_I2C y
+      FB_ATY_CT y # Mach64 CT/VT/GT/LT (incl. 3D RAGE) support
+      FB_ATY_GX y # Mach64 GX support
+      FB_SAVAGE_I2C y
+      FB_SAVAGE_ACCEL y
+      FB_SIS_300 y
+      FB_SIS_315 y
+      FB_3DFX_ACCEL y
+      FB_GEODE y
+
+      # Video configuration
+      # The intel drivers already require KMS
+      DRM_I915_KMS y
+
+      # Sound.
+      SND_AC97_POWER_SAVE y # AC97 Power-Saving Mode
+      SND_HDA_INPUT_BEEP y # Support digital beep via input layer
+      SND_USB_CAIAQ_INPUT y
+      PSS_MIXER y # Enable PSS mixer (Beethoven ADSP-16 and other compatible)
+
+      # USB serial devices.
+      USB_SERIAL_GENERIC y # USB Generic Serial Driver
+      USB_SERIAL_KEYSPAN_MPR y # include firmware for various USB serial devices
+      USB_SERIAL_KEYSPAN_USA28 y
+      USB_SERIAL_KEYSPAN_USA28X y
+      USB_SERIAL_KEYSPAN_USA28XA y
+      USB_SERIAL_KEYSPAN_USA28XB y
+      USB_SERIAL_KEYSPAN_USA19 y
+      USB_SERIAL_KEYSPAN_USA18X y
+      USB_SERIAL_KEYSPAN_USA19W y
+      USB_SERIAL_KEYSPAN_USA19QW y
+      USB_SERIAL_KEYSPAN_USA19QI y
+      USB_SERIAL_KEYSPAN_USA49W y
+      USB_SERIAL_KEYSPAN_USA49WLC y
+
+      # Filesystem options - in particular, enable extended attributes and
+      # ACLs for all filesystems that support them.
+      EXT2_FS_XATTR y # Ext2 extended attributes
+      EXT2_FS_POSIX_ACL y # Ext2 POSIX Access Control Lists
+      EXT2_FS_SECURITY y # Ext2 Security Labels
+      EXT2_FS_XIP y # Ext2 execute in place support
+      EXT4_FS_POSIX_ACL y
+      EXT4_FS_SECURITY y
+      REISERFS_FS_XATTR y
+      REISERFS_FS_POSIX_ACL y
+      REISERFS_FS_SECURITY y
+      JFS_POSIX_ACL y
+      JFS_SECURITY y
+      XFS_QUOTA y
+      XFS_POSIX_ACL y
+      XFS_RT y # XFS Realtime subvolume support
+      OCFS2_DEBUG_MASKLOG n
+      BTRFS_FS_POSIX_ACL y
+      UBIFS_FS_XATTR y
+      UBIFS_FS_ADVANCED_COMPR y
+      NFSD_V2_ACL y
+      NFSD_V3 y
+      NFSD_V3_ACL y
+      NFSD_V4 y
+      CIFS_XATTR y
+      CIFS_POSIX y
+
+      # Security related features.
+      STRICT_DEVMEM y # Filter access to /dev/mem
+      SECURITY_SELINUX_BOOTPARAM_VALUE 0 # disable SELinux by default
+
+      # Misc. options.
+      8139TOO_8129 y
+      8139TOO_PIO n # PIO is slower
+      AIC79XX_DEBUG_ENABLE n
+      AIC7XXX_DEBUG_ENABLE n
+      AIC94XX_DEBUG n
+      B43_PCMCIA y
+      BLK_DEV_BSG n
+      BLK_DEV_CMD640_ENHANCED y # CMD640 enhanced support
+      BLK_DEV_IDEACPI y # IDE ACPI support
+      BLK_DEV_INTEGRITY y
+      BSD_PROCESS_ACCT_V3 y
+      BT_HCIUART_BCSP y
+      BT_HCIUART_H4 y # UART (H4) protocol support
+      BT_HCIUART_LL y
+      BT_RFCOMM_TTY y # RFCOMM TTY support
+      CPU_FREQ_DEBUG n
+      CRASH_DUMP n
+      DMAR? n # experimental
+      DVB_DYNAMIC_MINORS y # we use udev
+      FUSION y # Fusion MPT device support
+      IDE_GD_ATAPI y # ATAPI floppy support
+      IRDA_ULTRA y # Ultra (connectionless) protocol
+      JOYSTICK_IFORCE_232 y # I-Force Serial joysticks and wheels
+      JOYSTICK_IFORCE_USB y # I-Force USB joysticks and wheels
+      JOYSTICK_XPAD_FF y # X-Box gamepad rumble support
+      JOYSTICK_XPAD_LEDS y # LED Support for Xbox360 controller 'BigX' LED
+      KALLSYMS_EXTRA_PASS n
+      LDM_PARTITION y # Windows Logical Disk Manager (Dynamic Disk) support
+      LEDS_TRIGGER_IDE_DISK y # LED IDE Disk Trigger
+      LOGIRUMBLEPAD2_FF y # Logitech Rumblepad 2 force feedback
+      LOGO n # not needed
+      MEDIA_ATTACH y
+      MEGARAID_NEWGEN y
+      MICROCODE_AMD y
+      MODVERSIONS y
+      MOUSE_PS2_ELANTECH y # Elantech PS/2 protocol extension
+      MTRR_SANITIZER y
+      NET_FC y # Fibre Channel driver support
+      PCI_LEGACY y
+      PPP_MULTILINK y # PPP multilink support
+      REGULATOR y # Voltage and Current Regulator Support
+      SCSI_LOGGING y # SCSI logging facility
+      SERIAL_8250 y # 8250/16550 and compatible serial support
+      SLIP_COMPRESSED y # CSLIP compressed headers
+      SLIP_SMART y
+      THERMAL_HWMON y # Hardware monitoring support
+      USB_DEBUG n
+      USB_EHCI_ROOT_HUB_TT y # Root Hub Transaction Translators
+      X86_CHECK_BIOS_CORRUPTION y
+      X86_MCE y
+
+      ${if kernelPlatform ? kernelExtraConfig then kernelPlatform.kernelExtraConfig else ""}
+      ${extraConfig}
+    '';
+in
+
 import ./generic.nix (
 
   rec {
@@ -11,198 +204,16 @@ import ./generic.nix (
       sha256 = "1inmam21w13nyf5imgdb5palhiap41zcxf9k32i4ck1w7gg3gqk3";
     };
 
-    features.iwlwifi = true;
+    config = configWithPlatform stdenv.platform;
+
+    platform = stdenv.platform;
 
-    config =
-      ''
-        # Don't include any debug features.
-        DEBUG_KERNEL n
-
-        # Support drivers that need external firmware.
-        STANDALONE n
-
-        # Make /proc/config.gz available.
-        IKCONFIG_PROC y
-
-        # Optimize with -O2, not -Os.
-        CC_OPTIMIZE_FOR_SIZE n
-
-        # Enable the kernel's built-in memory tester.
-        MEMTEST y
-
-        # Include the CFQ I/O scheduler in the kernel, rather than as a
-        # module, so that the initrd gets a good I/O scheduler.
-        IOSCHED_CFQ y
-
-        # Disable some expensive (?) features.
-        FTRACE n
-        KPROBES n
-        NUMA? n
-        PM_TRACE_RTC n
-
-        # Enable various subsystems.
-        ACCESSIBILITY y # Accessibility support
-        AUXDISPLAY y # Auxiliary Display support
-        DONGLE y # Serial dongle support
-        HIPPI y
-        MTD_COMPLEX_MAPPINGS y # needed for many devices
-        NET_POCKET y # enable pocket and portable adapters
-        SCSI_LOWLEVEL y # enable lots of SCSI devices
-        SCSI_LOWLEVEL_PCMCIA y
-        SPI y # needed for many devices
-        SPI_MASTER y
-        WAN y
-
-        # Networking options.
-        IP_PNP n
-        IPV6_PRIVACY y
-        NETFILTER_ADVANCED y
-        IP_VS_PROTO_TCP y
-        IP_VS_PROTO_UDP y
-        IP_VS_PROTO_ESP y
-        IP_VS_PROTO_AH y
-        IP_DCCP_CCID3 n # experimental
-        CLS_U32_PERF y
-        CLS_U32_MARK y
-
-        # Wireless networking.
-        IPW2100_MONITOR y # support promiscuous mode
-        IPW2200_MONITOR y # support promiscuous mode
-        IWLWIFI_SPECTRUM_MEASUREMENT y
-        IWL3945_SPECTRUM_MEASUREMENT y
-        IWL4965 y # Intel Wireless WiFi 4965AGN
-        IWL5000 y # Intel Wireless WiFi 5000AGN
-        HOSTAP_FIRMWARE y # Support downloading firmware images with Host AP driver
-        HOSTAP_FIRMWARE_NVRAM y
-
-        # Some settings to make sure that fbcondecor works - in particular,
-        # disable tileblitting and the drivers that need it.
-
-        # Enable various FB devices.
-        FB y
-        FB_EFI y
-        FB_NVIDIA_I2C y # Enable DDC Support
-        FB_RIVA_I2C y
-        FB_ATY_CT y # Mach64 CT/VT/GT/LT (incl. 3D RAGE) support
-        FB_ATY_GX y # Mach64 GX support
-        FB_SAVAGE_I2C y
-        FB_SAVAGE_ACCEL y
-        FB_SIS_300 y
-        FB_SIS_315 y
-        FB_3DFX_ACCEL y
-        FB_GEODE y
-
-        # Video configuration
-        # The intel drivers already require KMS
-        DRM_I915_KMS y
-
-        # Sound.
-        SND_AC97_POWER_SAVE y # AC97 Power-Saving Mode
-        SND_HDA_INPUT_BEEP y # Support digital beep via input layer
-        SND_USB_CAIAQ_INPUT y
-        PSS_MIXER y # Enable PSS mixer (Beethoven ADSP-16 and other compatible)
-
-        # USB serial devices.
-        USB_SERIAL_GENERIC y # USB Generic Serial Driver
-        USB_SERIAL_KEYSPAN_MPR y # include firmware for various USB serial devices
-        USB_SERIAL_KEYSPAN_USA28 y
-        USB_SERIAL_KEYSPAN_USA28X y
-        USB_SERIAL_KEYSPAN_USA28XA y
-        USB_SERIAL_KEYSPAN_USA28XB y
-        USB_SERIAL_KEYSPAN_USA19 y
-        USB_SERIAL_KEYSPAN_USA18X y
-        USB_SERIAL_KEYSPAN_USA19W y
-        USB_SERIAL_KEYSPAN_USA19QW y
-        USB_SERIAL_KEYSPAN_USA19QI y
-        USB_SERIAL_KEYSPAN_USA49W y
-        USB_SERIAL_KEYSPAN_USA49WLC y
-
-        # Filesystem options - in particular, enable extended attributes and
-        # ACLs for all filesystems that support them.
-        EXT2_FS_XATTR y # Ext2 extended attributes
-        EXT2_FS_POSIX_ACL y # Ext2 POSIX Access Control Lists
-        EXT2_FS_SECURITY y # Ext2 Security Labels
-        EXT2_FS_XIP y # Ext2 execute in place support
-        EXT4_FS_POSIX_ACL y
-        EXT4_FS_SECURITY y
-        REISERFS_FS_XATTR y
-        REISERFS_FS_POSIX_ACL y
-        REISERFS_FS_SECURITY y
-        JFS_POSIX_ACL y
-        JFS_SECURITY y
-        XFS_QUOTA y
-        XFS_POSIX_ACL y
-        XFS_RT y # XFS Realtime subvolume support
-        OCFS2_DEBUG_MASKLOG n
-        BTRFS_FS_POSIX_ACL y
-        UBIFS_FS_XATTR y
-        UBIFS_FS_ADVANCED_COMPR y
-        NFSD_V2_ACL y
-        NFSD_V3 y
-        NFSD_V3_ACL y
-        NFSD_V4 y
-        CIFS_XATTR y
-        CIFS_POSIX y
-
-        # Security related features.
-        STRICT_DEVMEM y # Filter access to /dev/mem
-        SECURITY_SELINUX_BOOTPARAM_VALUE 0 # disable SELinux by default
-
-        # Misc. options.
-        8139TOO_8129 y
-        8139TOO_PIO n # PIO is slower
-        AIC79XX_DEBUG_ENABLE n
-        AIC7XXX_DEBUG_ENABLE n
-        AIC94XX_DEBUG n
-        B43_PCMCIA y
-        BLK_DEV_BSG n
-        BLK_DEV_CMD640_ENHANCED y # CMD640 enhanced support
-        BLK_DEV_IDEACPI y # IDE ACPI support
-        BLK_DEV_INTEGRITY y
-        BSD_PROCESS_ACCT_V3 y
-        BT_HCIUART_BCSP y
-        BT_HCIUART_H4 y # UART (H4) protocol support
-        BT_HCIUART_LL y
-        BT_RFCOMM_TTY y # RFCOMM TTY support
-        CPU_FREQ_DEBUG n
-        CRASH_DUMP n
-        DMAR? n # experimental
-        DVB_DYNAMIC_MINORS y # we use udev
-        FUSION y # Fusion MPT device support
-        IDE_GD_ATAPI y # ATAPI floppy support
-        IRDA_ULTRA y # Ultra (connectionless) protocol
-        JOYSTICK_IFORCE_232 y # I-Force Serial joysticks and wheels
-        JOYSTICK_IFORCE_USB y # I-Force USB joysticks and wheels
-        JOYSTICK_XPAD_FF y # X-Box gamepad rumble support
-        JOYSTICK_XPAD_LEDS y # LED Support for Xbox360 controller 'BigX' LED
-        KALLSYMS_EXTRA_PASS n
-        LDM_PARTITION y # Windows Logical Disk Manager (Dynamic Disk) support
-        LEDS_TRIGGER_IDE_DISK y # LED IDE Disk Trigger
-        LOGIRUMBLEPAD2_FF y # Logitech Rumblepad 2 force feedback
-        LOGO n # not needed
-        MEDIA_ATTACH y
-        MEGARAID_NEWGEN y
-        MICROCODE_AMD y
-        MODVERSIONS y
-        MOUSE_PS2_ELANTECH y # Elantech PS/2 protocol extension
-        MTRR_SANITIZER y
-        NET_FC y # Fibre Channel driver support
-        PCI_LEGACY y
-        PPP_MULTILINK y # PPP multilink support
-        REGULATOR y # Voltage and Current Regulator Support
-        SCSI_LOGGING y # SCSI logging facility
-        SERIAL_8250 y # 8250/16550 and compatible serial support
-        SLIP_COMPRESSED y # CSLIP compressed headers
-        SLIP_SMART y
-        THERMAL_HWMON y # Hardware monitoring support
-        USB_DEBUG n
-        USB_EHCI_ROOT_HUB_TT y # Root Hub Transaction Translators
-        X86_CHECK_BIOS_CORRUPTION y
-        X86_MCE y
-
-        ${if platform ? kernelExtraConfig then platform.kernelExtraConfig else ""}
-        ${extraConfig}
-      '';
+    crossAttrs = {
+      config = configWithPlatform stdenv.cross.platform;
+      platform = stdenv.cross.platform;
+    };
+
+    features.iwlwifi = true;
   }
 
   // removeAttrs args ["extraConfig"]
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index bec3c8aeaefa9..f8da366d72d28 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -35,6 +35,7 @@
   config ? null
 
 , crossSystem ? null
+, platform ? (import ./platforms.nix).pc
 }:
 
 
@@ -180,7 +181,7 @@ let
     allPackages = args: import ./all-packages.nix ({ inherit config; } // args);
   };
 
-  defaultStdenv = allStdenvs.stdenv;
+  defaultStdenv = allStdenvs.stdenv // { inherit platform; };
 
   stdenvCross = makeStdenvCross defaultStdenv crossSystem (binutilsCross crossSystem)
     (gccCrossStageFinal crossSystem);
@@ -291,7 +292,7 @@ let
   };
 
   makeInitrd = {contents}: import ../build-support/kernel/make-initrd.nix {
-    inherit stdenv perl cpio contents platform;
+    inherit stdenv perl cpio contents ubootChooser;
   };
 
   makeWrapper = makeSetupHook ../build-support/make-wrapper/make-wrapper.sh;
@@ -326,11 +327,7 @@ let
     inherit pkgs lib;
   };
 
-  platforms = import ./platforms.nix {
-    inherit system pkgs;
-  };
-
-  platform = platforms.pc;
+  platforms = import ./platforms.nix;
 
   ### TOOLS
 
@@ -5845,7 +5842,8 @@ let
   linuxHeaders = linuxHeaders_2_6_28;
 
   linuxHeadersCross = cross : forceBuildDrv (import ../os-specific/linux/kernel-headers/2.6.32.nix {
-    inherit stdenv fetchurl cross perl platform;
+    inherit stdenv fetchurl cross perl;
+    platform = cross.platform;
   });
 
   linuxHeaders_2_6_18 = import ../os-specific/linux/kernel-headers/2.6.18.5.nix {
@@ -5903,12 +5901,11 @@ let
   };
 
   linux_2_6_32 = makeOverridable (import ../os-specific/linux/kernel/linux-2.6.32.nix) {
-    inherit fetchurl stdenv perl mktemp module_init_tools;
+    inherit fetchurl stdenv perl mktemp module_init_tools ubootChooser;
     kernelPatches =
       [ kernelPatches.fbcondecor_2_6_31
         kernelPatches.sec_perm_2_6_24
       ];
-    inherit platform;
   };
 
   linux_2_6_32_zen4 = makeOverridable (import ../os-specific/linux/zen-kernel/2.6.32-zen4.nix) {
@@ -5928,12 +5925,11 @@ let
   };
 
   linux_2_6_33 = makeOverridable (import ../os-specific/linux/kernel/linux-2.6.33.nix) {
-    inherit fetchurl stdenv perl mktemp module_init_tools;
+    inherit fetchurl stdenv perl mktemp module_init_tools ubootChooser;
     kernelPatches =
       [ kernelPatches.fbcondecor_2_6_33
         kernelPatches.sec_perm_2_6_24
       ];
-    inherit platform;
   };
 
   /* Linux kernel modules are inherently tied to a specific kernel.  So
@@ -6347,7 +6343,11 @@ let
     inherit (xlibs) libX11 xproto;
   };*/
 
-  uboot = makeOverridable (import ../misc/uboot) {
+  ubootChooser = name : if (name == "upstream") then ubootUpstream
+    else if (name == "sheevaplug") then ubootSheevaplug
+    else throw "Unknown uboot";
+
+  ubootUpstream  = makeOverridable (import ../misc/uboot) {
     inherit fetchurl stdenv unzip platform;
   };
 
diff --git a/pkgs/top-level/platforms.nix b/pkgs/top-level/platforms.nix
index 9cd209a755225..4b1fb3152873d 100644
--- a/pkgs/top-level/platforms.nix
+++ b/pkgs/top-level/platforms.nix
@@ -1,7 +1,5 @@
-{ system, pkgs}:
-with pkgs;
 rec {
-  pc = assert system == "i686-linux" || system == "x86_64-linux"; {
+  pc = {
     name = "pc";
     uboot = null;
     kernelBaseConfig = "defconfig";
@@ -60,7 +58,7 @@ rec {
         IP_PNP y
       '';
     kernelTarget = "uImage";
-    uboot = ubootSheevaplug;
+    uboot = "sheevaplug";
     # Only for uboot = uboot :
     ubootConfig = "sheevaplug_config";
   };
@@ -133,7 +131,7 @@ rec {
   integratorCPuboot = integratorCP // {
     name = "integratorCPuboot";
     kernelTarget = "uImage";
-    uboot = uboot;
+    uboot = "upstream";
     ubootConfig = "integratorcp_config";
   };
 }