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diff --git a/doc/supplements/i386/cpumodel.texi b/doc/supplements/i386/cpumodel.texi deleted file mode 100644 index d10ccf85f7..0000000000 --- a/doc/supplements/i386/cpumodel.texi +++ /dev/null @@ -1,96 +0,0 @@ -@c -@c COPYRIGHT (c) 1988-1998. -@c On-Line Applications Research Corporation (OAR). -@c All rights reserved. -@c -@c $Id$ -@c - -@ifinfo -@node CPU Model Dependent Features, CPU Model Dependent Features Introduction, Preface, Top -@end ifinfo -@chapter CPU Model Dependent Features -@ifinfo -@menu -* CPU Model Dependent Features Introduction:: -* CPU Model Dependent Features CPU Model Name:: -* CPU Model Dependent Features bswap Instruction:: -* CPU Model Dependent Features Floating Point Unit:: -@end menu -@end ifinfo - -@ifinfo -@node CPU Model Dependent Features Introduction, CPU Model Dependent Features CPU Model Name, CPU Model Dependent Features, CPU Model Dependent Features -@end ifinfo -@section Introduction - -Microprocessors are generally classified into -families with a variety of CPU models or implementations within -that family. Within a processor family, there is a high level -of binary compatibility. This family may be based on either an -architectural specification or on maintaining compatibility with -a popular processor. Recent microprocessor families such as the -SPARC or PA-RISC are based on an architectural specification -which is independent or any particular CPU model or -implementation. Older families such as the M68xxx and the iX86 -evolved as the manufacturer strived to produce higher -performance processor models which maintained binary -compatibility with older models. - -RTEMS takes advantage of the similarity of the -various models within a CPU family. Although the models do vary -in significant ways, the high level of compatibility makes it -possible to share the bulk of the CPU dependent executive code -across the entire family. Each processor family supported by -RTEMS has a list of features which vary between CPU models -within a family. For example, the most common model dependent -feature regardless of CPU family is the presence or absence of a -floating point unit or coprocessor. When defining the list of -features present on a particular CPU model, one simply notes -that floating point hardware is or is not present and defines a -single constant appropriately. Conditional compilation is -utilized to include the appropriate source code for this CPU -model's feature set. It is important to note that this means -that RTEMS is thus compiled using the appropriate feature set -and compilation flags optimal for this CPU model used. The -alternative would be to generate a binary which would execute on -all family members using only the features which were always -present. - -This chapter presents the set of features which vary -across i386 implementations and are of importance to RTEMS. -The set of CPU model feature macros are defined in the file -c/src/exec/score/cpu/i386/i386.h based upon the particular CPU -model defined on the compilation command line. - -@ifinfo -@node CPU Model Dependent Features CPU Model Name, CPU Model Dependent Features bswap Instruction, CPU Model Dependent Features Introduction, CPU Model Dependent Features -@end ifinfo -@section CPU Model Name - -The macro CPU_MODEL_NAME is a string which designates -the name of this CPU model. For example, for the Intel i386 without an -i387 coprocessor, this macro is set to the string "i386 with i387". - -@ifinfo -@node CPU Model Dependent Features bswap Instruction, CPU Model Dependent Features Floating Point Unit, CPU Model Dependent Features CPU Model Name, CPU Model Dependent Features -@end ifinfo -@section bswap Instruction - -The macro I386_HAS_BSWAP is set to 1 to indicate that -this CPU model has the @code{bswap} instruction which -endian swaps a thirty-two bit quantity. This instruction -appears to be present in all CPU models -i486's and above. - - -@ifinfo -@node CPU Model Dependent Features Floating Point Unit, Calling Conventions, CPU Model Dependent Features bswap Instruction , CPU Model Dependent Features -@end ifinfo -@section Floating Point Unit - -The macro I386_HAS_FPU is set to 1 to indicate that -this CPU model has a hardware floating point unit and 0 -otherwise. The hardware floating point may be on-chip (as in the -case of an i486DX or Pentium) or as a coprocessor (as in the case of -an i386/i387 combination). |