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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/m68k/ifpsp060/ilsp.doc | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/m68k/ifpsp060/ilsp.doc')
-rw-r--r-- | arch/m68k/ifpsp060/ilsp.doc | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/arch/m68k/ifpsp060/ilsp.doc b/arch/m68k/ifpsp060/ilsp.doc new file mode 100644 index 000000000000..f6fae6d900ae --- /dev/null +++ b/arch/m68k/ifpsp060/ilsp.doc @@ -0,0 +1,150 @@ +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +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. +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +68060 INTEGER SOFTWARE PACKAGE (Library version) +------------------------------------------------- + +The file ilsp.s contains the "Library version" of the +68060 Integer Software Package. Routines included in this +module can be used to emulate 64-bit divide and multiply, +and the "cmp2" instruction. These instructions are not +implemented in hardware on the 68060 and normally take +exception vector #61 "Unimplemented Integer Instruction". + +By re-compiling a program that uses these instructions, and +making subroutine calls in place of the unimplemented +instructions, a program can avoid the overhead associated with +taking the exception. + +Release file format: +-------------------- +The file ilsp.sa is essentially a hexadecimal image of the +release package. This is the ONLY format which will be supported. +The hex image was created by assembling the source code and +then converting the resulting binary output image into an +ASCII text file. The hexadecimal numbers are listed +using the Motorola Assembly Syntax assembler directive "dc.l" +(define constant longword). The file can be converted to other +assembly syntaxes by using any word processor with a global +search and replace function. + +To assist in assembling and linking this module with other modules, +the installer should add a symbolic label to the top of the file. +This will allow calling routines to access the entry points +of this package. + +The source code ilsp.s has also been included but only for +documentation purposes. + +Release file structure: +----------------------- +The file ilsp.sa contains an "Entry-Point" section and a +code section. The ILSP has no "Call-Out" section. The first section +is the "Entry-Point" section. In order to access a function in the +package, a program must "bsr" or "jsr" to the location listed +below in "68060ILSP Entry Points" that corresponds to the desired +function. A branch instruction located at the selected entry point +within the package will then enter the correct emulation code routine. + +The entry point addresses at the beginning of the package will remain +fixed so that a program calling the routines will not have to be +re-compiled with every new 68060ILSP release. + +For example, to use a 64-bit multiply instruction, +do a "bsr" or "jsr" to the entry point defined by +the 060ILSP entry table. A compiler generated code sequence +for unsigned multiply could look like: + +# mulu.l <ea>,Dh:Dl +# mulu.l _multiplier,%d1:%d0 + + subq.l &0x8,%sp # make room for result on stack + pea (%sp) # pass: result addr on stack + mov.l %d0,-(%sp) # pass: multiplicand on stack + mov.l _multiplier,-(%sp) # pass: multiplier on stack + bsr.l _060LISP_TOP+0x18 # branch to multiply routine + add.l &0xc,%sp # clear arguments from stack + mov.l (%sp)+,%d1 # load result[63:32] + mov.l (%sp)+,%d0 # load result[31:0] + +For a divide: + +# divu.l <ea>,Dr:Dq +# divu.l _divisor,%d1:%d0 + + subq.l &0x8,%sp # make room for result on stack + pea (%sp) # pass: result addr on stack + mov.l %d0,-(%sp) # pass: dividend hi on stack + mov.l %d1,-(%sp) # pass: dividend hi on stack + mov.l _divisor,-(%sp) # pass: divisor on stack + bsr.l _060LISP_TOP+0x08 # branch to divide routine + add.l &0xc,%sp # clear arguments from stack + mov.l (%sp)+,%d1 # load remainder + mov.l (%sp)+,%d0 # load quotient + +The library routines also return the correct condition code +register value. If this is important, then the caller of the library +routine must make sure that the value isn't lost while popping +other items off of the stack. + +An example of using the "cmp2" instruction is as follows: + +# cmp2.l <ea>,Rn +# cmp2.l _bounds,%d0 + + pea _bounds # pass ptr to bounds + mov.l %d0,-(%sp) # pass Rn + bsr.l _060LSP_TOP_+0x48 # branch to "cmp2" routine + mov.w %cc,_tmp # save off condition codes + addq.l &0x8,%sp # clear arguments from stack + +Exception reporting: +-------------------- +If the instruction being emulated is a divide and the source +operand is a zero, then the library routine, as its last +instruction, executes an implemented divide using a zero +source operand so that an "Integer Divide-by-Zero" exception +will be taken. Although the exception stack frame will not +point to the correct instruction, the user will at least be able +to record that such an event occurred if desired. + +68060ILSP entry points: +----------------------- +_060ILSP_TOP: +0x000: _060LSP__idivs64_ +0x008: _060LSP__idivu64_ + +0x010: _060LSP__imuls64_ +0x018: _060LSP__imulu64_ + +0x020: _060LSP__cmp2_Ab_ +0x028: _060LSP__cmp2_Aw_ +0x030: _060LSP__cmp2_Al_ +0x038: _060LSP__cmp2_Db_ +0x040: _060LSP__cmp2_Dw_ +0x048: _060LSP__cmp2_Dl_ |