Various license header consistency fixes (trivial).

[coreboot.git] / src / devices / Kconfig

diff --git a/src/devices/Kconfig b/src/devices/Kconfig
index 96084f95b2c3806038b2752572c7ce9b8ec0a0ca..42c47bc19ceea4896be079c58c44be3bf93f03d3 100644 (file)
--- a/src/devices/Kconfig
+++ b/src/devices/Kconfig
@@ -6,7 +6,7 @@
 ##
 ## This program is free software; you can redistribute it and/or modify
 ## it under the terms of the GNU General Public License as published by
-## the Free Software Foundation; version 2 of the License
+## the Free Software Foundation; version 2 of the License.
 ##
 ## This program is distributed in the hope that it will be useful,
 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -42,34 +42,71 @@ config PCI_ROM_RUN
          Examples include IDE/SATA controller option ROMs and option ROMs
          for network cards (NICs).
 
-# TODO: Describe YABEL vs. x86emu differences in more detail.
 choice
        prompt "Option ROM execution type"
-       default PCI_OPTION_ROM_RUN_REALMODE
+       default PCI_OPTION_ROM_RUN_YABEL if !ARCH_X86
+       default PCI_OPTION_ROM_RUN_REALMODE if ARCH_X86
        depends on PCI_ROM_RUN || VGA_ROM_RUN
 
 config PCI_OPTION_ROM_RUN_REALMODE
        prompt "Real mode"
        bool
+       depends on ARCH_X86
        help
          If you select this option, PCI option ROMs will be executed
-         natively on the hardware (a 32bit x86 system is required).
+         natively on the CPU in real mode. No CPU emulation is involved,
+         so this is the fastest, but also the least secure option.
+         (only works on x86/x64 systems)
+
+config PCI_OPTION_ROM_RUN_X86EMU
+       prompt "x86emu"
+       bool
+       help
+         If you select this option, the x86emu CPU emulator will be used to
+         execute PCI option ROMs. 
+         When choosing this option, x86emu will pass through all hardware
+         accesses to memory and IO devices to the underlying memory and IO
+         addresses. While this option prevents option ROMs from doing dirty
+         tricks with the CPU (such as installing SMM modules or hypervisors),
+         they can still access all devices in the system.
+         Choosing x86emu, option ROM execution is slower than native execution
+         in real mode, but faster than the full system emulation YABEL
+         This is the default choice for non-x86 systems.
 
 config PCI_OPTION_ROM_RUN_YABEL
        prompt "YABEL"
        bool
        help
-         If you select this option, the YABEL BIOS emulator will be used to
+         If you select this option, the YABEL system emulator will be used to
          execute PCI option ROMs.
+         YABEL consists of two parts: It uses x86emu for the CPU emulation and
+         additionally provides a PC system emulation that filters bad device and
+         memory access (such as PCI config space access to other devices than the
+         initialized one).
+         This option best prevents option ROMs from doing dirty tricks with the 
+         system (such as installing SMM modules or hypervisors), but it is also
+         significantly slower than the other option ROM initialization methods.
 
-config PCI_OPTION_ROM_RUN_X86EMU
-       prompt "x86emu"
+endchoice
+
+config YABEL_PCI_ACCESS_OTHER_DEVICES
+       prompt "Allow option roms to acces other devices"
        bool
+       depends on PCI_OPTION_ROM_RUN_YABEL
        help
-         If you select this option, the x86emu BIOS emulator will be used to
-         execute PCI option ROMs.
+         Per default, YABEL only allows option roms to access the PCI device
+         that they are associated with. However, this causes trouble for some
+         onboard graphics chips whose option rom needs to reconfigure the 
+         north bridge. 
 
-endchoice
+config YABEL_VIRTMEM_LOCATION
+       prompt "Location of YABEL's virtual memory"
+       hex
+       depends on EXPERT
+       default 0x1000000
+       help
+         YABEL requires 1MB memory for its CPU emulation. This memory is
+         normally located at 16MB.
 
 # TODO: Describe better, and/or make a "choice" selection for this.
 config YABEL_DEBUG_FLAGS