diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/arm/nwfpe/README | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/Documentation/arm/nwfpe/README')
-rw-r--r-- | kernel/Documentation/arm/nwfpe/README | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/kernel/Documentation/arm/nwfpe/README b/kernel/Documentation/arm/nwfpe/README new file mode 100644 index 000000000..771871de0 --- /dev/null +++ b/kernel/Documentation/arm/nwfpe/README @@ -0,0 +1,70 @@ +This directory contains the version 0.92 test release of the NetWinder +Floating Point Emulator. + +The majority of the code was written by me, Scott Bambrough It is +written in C, with a small number of routines in inline assembler +where required. It was written quickly, with a goal of implementing a +working version of all the floating point instructions the compiler +emits as the first target. I have attempted to be as optimal as +possible, but there remains much room for improvement. + +I have attempted to make the emulator as portable as possible. One of +the problems is with leading underscores on kernel symbols. Elf +kernels have no leading underscores, a.out compiled kernels do. I +have attempted to use the C_SYMBOL_NAME macro wherever this may be +important. + +Another choice I made was in the file structure. I have attempted to +contain all operating system specific code in one module (fpmodule.*). +All the other files contain emulator specific code. This should allow +others to port the emulator to NetBSD for instance relatively easily. + +The floating point operations are based on SoftFloat Release 2, by +John Hauser. SoftFloat is a software implementation of floating-point +that conforms to the IEC/IEEE Standard for Binary Floating-point +Arithmetic. As many as four formats are supported: single precision, +double precision, extended double precision, and quadruple precision. +All operations required by the standard are implemented, except for +conversions to and from decimal. We use only the single precision, +double precision and extended double precision formats. The port of +SoftFloat to the ARM was done by Phil Blundell, based on an earlier +port of SoftFloat version 1 by Neil Carson for NetBSD/arm32. + +The file README.FPE contains a description of what has been implemented +so far in the emulator. The file TODO contains a information on what +remains to be done, and other ideas for the emulator. + +Bug reports, comments, suggestions should be directed to me at +<scottb@netwinder.org>. General reports of "this program doesn't +work correctly when your emulator is installed" are useful for +determining that bugs still exist; but are virtually useless when +attempting to isolate the problem. Please report them, but don't +expect quick action. Bugs still exist. The problem remains in isolating +which instruction contains the bug. Small programs illustrating a specific +problem are a godsend. + +Legal Notices +------------- + +The NetWinder Floating Point Emulator is free software. Everything Rebel.com +has written is provided under the GNU GPL. See the file COPYING for copying +conditions. Excluded from the above is the SoftFloat code. John Hauser's +legal notice for SoftFloat is included below. + +------------------------------------------------------------------------------- +SoftFloat Legal Notice + +SoftFloat was written by John R. Hauser. This work was made possible in +part by the International Computer Science Institute, located at Suite 600, +1947 Center Street, Berkeley, California 94704. Funding was partially +provided by the National Science Foundation under grant MIP-9311980. The +original version of this code was written as part of a project to build +a fixed-point vector processor in collaboration with the University of +California at Berkeley, overseen by Profs. Nelson Morgan and John Wawrzynek. + +THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort +has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT +TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO +PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY +AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE. +------------------------------------------------------------------------------- |