linux-stable-rt/arch/m68k/ifpsp060/CHANGES

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MOTOROLA MICROPROCESSOR & MEMORY TECHNOLOGY GROUP
M68000 Hi-Performance Microprocessor Division
M68060 Software Package
Production Release P1.00 -- October 10, 1994
M68060 Software Package Copyright © 1993, 1994 Motorola Inc. All rights reserved.
THE SOFTWARE is provided on an "AS IS" basis and without warranty.
To the maximum extent permitted by applicable law,
MOTOROLA DISCLAIMS ALL WARRANTIES WHETHER EXPRESS OR IMPLIED,
INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
and any warranty against infringement with regard to the SOFTWARE
(INCLUDING ANY MODIFIED VERSIONS THEREOF) and any accompanying written materials.
To the maximum extent permitted by applicable law,
IN NO EVENT SHALL MOTOROLA BE LIABLE FOR ANY DAMAGES WHATSOEVER
(INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS PROFITS,
BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR OTHER PECUNIARY LOSS)
ARISING OF THE USE OR INABILITY TO USE THE SOFTWARE.
Motorola assumes no responsibility for the maintenance and support of the SOFTWARE.
You are hereby granted a copyright license to use, modify, and distribute the SOFTWARE
so long as this entire notice is retained without alteration in any modified and/or
redistributed versions, and that such modified versions are clearly identified as such.
No licenses are granted by implication, estoppel or otherwise under any patents
or trademarks of Motorola, Inc.
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CHANGES SINCE LAST RELEASE:
---------------------------
1) "movep" emulation where data was being read from memory
was reading the intermediate bytes. Emulation now only
reads the required bytes.
2) "flogn", "flog2", and "flog10" of "1" was setting the
Inexact FPSR bit. Emulation now does not set Inexact for
this case.
3) For an opclass three FP instruction where the effective addressing
mode was pre-decrement or post-increment and the address register
was A0 or A1, the address register was not being updated as a result
of the operation. This has been corrected.
4) Beta B.2 version had the following erratum:
Scenario:
---------
If {i,d}mem_{read,write}_{byte,word,long}() returns
a failing value to the 68060SP, the package ignores
this return value and continues with program execution
as if it never received a failing value.
Effect:
-------
For example, if a user executed "fsin.x ADDR,fp0" where
ADDR should cause a "segmentation violation", the memory read
requested by the package should return a failing value
to the package. Since the package currently ignores this
return value, the user program will continue to the
next instruction, and the result created in fp0 will be
undefined.
Fix:
----
This has been fixed in the current release.
Notes:
------
Upon receiving a non-zero (failing) return value from
a {i,d}mem_{read,write}_{byte,word,long}() "call-out",
the package creates a 16-byte access error stack frame
from the current exception stack frame and exits
through the "call-out" _real_access(). This is the process
as described in the MC68060 User's Manual.
For instruction read access errors, the info stacked is:
SR = SR at time of exception
PC = PC of instruction being emulated
VOFF = $4008 (stack frame format type)
ADDRESS = PC of instruction being emulated
FSLW = FAULT STATUS LONGWORD
The valid FSLW bits are:
bit 27 = 1 (misaligned bit)
bit 24 = 1 (read)
bit 23 = 0 (write)
bit 22:21 = 10 (SIZE = word)
bit 20:19 = 00 (TT)
bit 18:16 = x10 (TM; x = 1 for supervisor mode)
bit 15 = 1 (IO)
bit 0 = 1 (Software Emulation Error)
all other bits are EQUAL TO ZERO and can be set by the _real_access()
"call-out" stub by the user as appropriate. The MC68060 User's Manual
stated that ONLY "bit 0" would be set. The 060SP attempts to set a few
other bits.
For data read/write access errors, the info stacked is:
SR = SR at time of exception
PC = PC of instruction being emulated
VOFF = $4008 (stack frame format type)
ADDRESS = Address of source or destination operand
FSLW = FAULT STATUS LONGWORD
The valid FSLW bits are:
bit 27 = 0 (misaligned bit)
bit 24 = x (read; 1 if read, 0 if write)
bit 23 = x (write; 1 if write, 0 if read)
bit 22:21 = xx (SIZE; see MC68060 User's Manual)
bit 20:19 = 00 (TT)
bit 18:16 = x01 (TM; x = 1 for supervisor mode)
bit 15 = 0 (IO)
bit 0 = 1 (Software Emulation Error)
all other bits are EQUAL TO ZERO and can be set by the _real_access()
"call-out" stub by the user as appropriate. The MC68060 User's Manual
stated that ONLY "bit 0" would be set. The 060SP attempts to set a few
other bits.