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Adrian-Ken Rueegsegger 7ce8464b3a hw_x86_64: Enable FPU support * Enable the use of the FXSAVE and FXRSTOR instructions, see Intel SDM Vol. 3C, section 2.5. * The state of the x87 floating point unit (FPU) is loaded and saved on demand. * Make the cr0 control register accessible in the Cpu class. This is in preparation of the upcoming FPU management. * Access to the FPU is disabled by setting the Task Switch flag in the cr0 register. * Access to the FPU is enabled by clearing the Task Switch flag in the cr0 register. * Implement FPU initialization * Add is_fpu_enabled helper function * Add pointer to CPU lazy state to CPU class * Init FPU when finishing kernel initialization * Add function to retry FPU instruction: Similar to the ARM mechanism to retry undefined instructions, implement a function for retrying an FPU instruction. If a floating-point instruction causes an #NM exception due to the FPU being disabled, it can be retried after the correct FPU state is restored, saving the current state and enabling the FPU in the process. * Disable FPU when switching to different user context: This enables lazy save/restore of the FPU since trying to execute a floating point instruction when the FPU is disabled will cause a #NM exception. * Declare constant for #NM exception * Retry FPU instruction on #NM exception * Assure alignment of FXSAVE area: The FXSAVE area is 512-byte memory region that must be 16-byte aligned. As it turns out the alignment attribute is not honored in all cases so add a workaround to assure the alignment constraint is met by manually rounding the start of the FXSAVE area to the next 16-byte boundary if necessary.		2015-03-27 11:53:31 +01:00
doc	Remove repos/qt4, fix #1451	2015-03-19 08:57:20 +01:00
repos	hw_x86_64: Enable FPU support	2015-03-27 11:53:31 +01:00
tool	hw: Use properly sized asm type in boot_modules.s	2015-03-27 11:53:16 +01:00
.gitignore	gdb: save generated files in the build directory	2015-03-13 12:17:26 +01:00
LICENSE	Imported Genode release 11.11	2011-12-22 16:19:25 +01:00
README	Move repositories to 'repos/' subdirectory	2014-05-14 16:08:00 +02:00
VERSION	version: 15.02	2015-02-27 11:57:59 +01:00

README

                      =================================
                      Genode Operating System Framework
                      =================================


This is the source tree of the reference implementation of the Genode OS
architecture. For a general overview about the architecture, please refer to
the project's official website:

:Official project website for the Genode OS Framework:

  [http://genode.org/documentation/general-overview]

The current implementation can be compiled for 8 different kernels: Linux,
L4ka::Pistachio, L4/Fiasco, OKL4, NOVA, Fiasco.OC, Codezero, and a custom
kernel for running Genode directly on ARM-based hardware. Whereas the Linux
version serves us as development vehicle and enables us to rapidly develop the
generic parts of the system, the actual target platforms of the framework are
microkernels. There is no "perfect" microkernel - and neither should there be
one. If a microkernel pretended to be fit for all use cases, it wouldn't be
"micro". Hence, all microkernels differ in terms of their respective features,
complexity, and supported hardware architectures.

Genode allows the use of each of the kernels listed above with a rich set of
device drivers, protocol stacks, libraries, and applications in a uniform way.
For developers, the framework provides an easy way to target multiple different
kernels instead of tying the development to a particular kernel technology. For
kernel developers, Genode contributes advanced workloads, stress-testing their
kernel, and enabling a variety of application use cases that would not be
possible otherwise. For users and system integrators, it enables the choice of
the kernel that fits best with the requirements at hand for the particular
usage scenario.


Directory overview
##################

The source tree is composed of the following subdirectories:

:'doc':

  This directory contains general documentation. Please consider the following
  document for a quick guide to get started with the framework:

  ! doc/getting_started.txt

  If you are curious about the ready-to-use components that come with the
  framework, please review the components overview:

  ! doc/components.txt

:'repos':

  This directory contains the so-called source-code repositories of Genode.
  Please refer to the README file in the 'repos' directory to learn more
  about the roles of the individual repositories.

:'tool':

  Source-code management tools and scripts. Please refer to the README file
  contained in the directory.


Contact
#######

The best way to get in touch with Genode developers and users is the project's
mailing list. Please feel welcome to join in!

:Genode Mailing Lists:

  [http://genode.org/community/mailing-lists]