diff options
author | Joel Sherrill <joel.sherrill@OARcorp.com> | 2006-08-23 19:11:14 +0000 |
---|---|---|
committer | Joel Sherrill <joel.sherrill@OARcorp.com> | 2006-08-23 19:11:14 +0000 |
commit | 83fb86f32b73942be758c22423c0bfe506fd4ff6 (patch) | |
tree | d51a136781eaccf67bfb2addfbe5330d9aed4791 /doc/supplements/i386/intr_NOTIMES.t | |
parent | 2006-08-23 Joel Sherrill <joel@OARcorp.com> (diff) | |
download | rtems-83fb86f32b73942be758c22423c0bfe506fd4ff6.tar.bz2 |
2006-08-23 Joel Sherrill <joel@OARcorp.com>
* Makefile.am, configure.ac, FAQ/stamp-vti, FAQ/version.texi,
common/cpright.texi: Merging CPU Supplements into a single document.
As part of this removed the obsolete and impossible to maintain size
and timing information.
* cpu_supplement/.cvsignore, cpu_supplement/Makefile.am,
cpu_supplement/arm.t, cpu_supplement/i386.t, cpu_supplement/m68k.t,
cpu_supplement/mips.t, cpu_supplement/powerpc.t,
cpu_supplement/preface.texi, cpu_supplement/sh.t,
cpu_supplement/sparc.t, cpu_supplement/tic4x.t: New files.
* supplements/.cvsignore, supplements/Makefile.am,
supplements/supplement.am, supplements/arm/.cvsignore,
supplements/arm/BSP_TIMES, supplements/arm/ChangeLog,
supplements/arm/Makefile.am, supplements/arm/arm.texi,
supplements/arm/bsp.t, supplements/arm/callconv.t,
supplements/arm/cpumodel.t, supplements/arm/cputable.t,
supplements/arm/fatalerr.t, supplements/arm/intr_NOTIMES.t,
supplements/arm/memmodel.t, supplements/arm/preface.texi,
supplements/arm/timeBSP.t, supplements/c4x/.cvsignore,
supplements/c4x/BSP_TIMES, supplements/c4x/ChangeLog,
supplements/c4x/Makefile.am, supplements/c4x/bsp.t,
supplements/c4x/c4x.texi, supplements/c4x/callconv.t,
supplements/c4x/cpumodel.t, supplements/c4x/cputable.t,
supplements/c4x/fatalerr.t, supplements/c4x/intr_NOTIMES.t,
supplements/c4x/memmodel.t, supplements/c4x/preface.texi,
supplements/c4x/timeBSP.t, supplements/i386/.cvsignore,
supplements/i386/ChangeLog, supplements/i386/FORCE386_TIMES,
supplements/i386/Makefile.am, supplements/i386/bsp.t,
supplements/i386/callconv.t, supplements/i386/cpumodel.t,
supplements/i386/cputable.t, supplements/i386/fatalerr.t,
supplements/i386/i386.texi, supplements/i386/intr_NOTIMES.t,
supplements/i386/memmodel.t, supplements/i386/preface.texi,
supplements/i386/timeFORCE386.t, supplements/m68k/.cvsignore,
supplements/m68k/ChangeLog, supplements/m68k/MVME136_TIMES,
supplements/m68k/Makefile.am, supplements/m68k/bsp.t,
supplements/m68k/callconv.t, supplements/m68k/cpumodel.t,
supplements/m68k/cputable.t, supplements/m68k/fatalerr.t,
supplements/m68k/intr_NOTIMES.t, supplements/m68k/m68k.texi,
supplements/m68k/memmodel.t, supplements/m68k/preface.texi,
supplements/m68k/timeMVME136.t, supplements/m68k/timedata.t,
supplements/mips/.cvsignore, supplements/mips/BSP_TIMES,
supplements/mips/ChangeLog, supplements/mips/Makefile.am,
supplements/mips/bsp.t, supplements/mips/callconv.t,
supplements/mips/cpumodel.t, supplements/mips/cputable.t,
supplements/mips/fatalerr.t, supplements/mips/intr_NOTIMES.t,
supplements/mips/memmodel.t, supplements/mips/mips.texi,
supplements/mips/preface.texi, supplements/mips/timeBSP.t,
supplements/powerpc/.cvsignore, supplements/powerpc/ChangeLog,
supplements/powerpc/DMV177_TIMES, supplements/powerpc/Makefile.am,
supplements/powerpc/PSIM_TIMES, supplements/powerpc/bsp.t,
supplements/powerpc/callconv.t, supplements/powerpc/cpumodel.t,
supplements/powerpc/cputable.t, supplements/powerpc/fatalerr.t,
supplements/powerpc/intr_NOTIMES.t, supplements/powerpc/memmodel.t,
supplements/powerpc/powerpc.texi, supplements/powerpc/preface.texi,
supplements/powerpc/timeDMV177.t, supplements/powerpc/timePSIM.t,
supplements/sh/.cvsignore, supplements/sh/BSP_TIMES,
supplements/sh/ChangeLog, supplements/sh/Makefile.am,
supplements/sh/bsp.t, supplements/sh/callconv.t,
supplements/sh/cpumodel.t, supplements/sh/cputable.t,
supplements/sh/fatalerr.t, supplements/sh/intr_NOTIMES.t,
supplements/sh/memmodel.t, supplements/sh/preface.texi,
supplements/sh/sh.texi, supplements/sh/timeBSP.t,
supplements/sparc/.cvsignore, supplements/sparc/ChangeLog,
supplements/sparc/ERC32_TIMES, supplements/sparc/Makefile.am,
supplements/sparc/bsp.t, supplements/sparc/callconv.t,
supplements/sparc/cpumodel.t, supplements/sparc/cputable.t,
supplements/sparc/fatalerr.t, supplements/sparc/intr_NOTIMES.t,
supplements/sparc/memmodel.t, supplements/sparc/preface.texi,
supplements/sparc/sparc.texi, supplements/sparc/timeERC32.t,
supplements/template/.cvsignore, supplements/template/BSP_TIMES,
supplements/template/ChangeLog, supplements/template/Makefile.am,
supplements/template/bsp.t, supplements/template/callconv.t,
supplements/template/cpumodel.t, supplements/template/cputable.t,
supplements/template/fatalerr.t, supplements/template/intr_NOTIMES.t,
supplements/template/memmodel.t, supplements/template/preface.texi,
supplements/template/template.texi, supplements/template/timeBSP.t: Removed.
Diffstat (limited to 'doc/supplements/i386/intr_NOTIMES.t')
-rw-r--r-- | doc/supplements/i386/intr_NOTIMES.t | 168 |
1 files changed, 0 insertions, 168 deletions
diff --git a/doc/supplements/i386/intr_NOTIMES.t b/doc/supplements/i386/intr_NOTIMES.t deleted file mode 100644 index 1db03127ec..0000000000 --- a/doc/supplements/i386/intr_NOTIMES.t +++ /dev/null @@ -1,168 +0,0 @@ -@c -@c COPYRIGHT (c) 1988-2002. -@c On-Line Applications Research Corporation (OAR). -@c All rights reserved. -@c -@c $Id$ -@c - -@chapter Interrupt Processing - -@section Introduction - -Different types of processors respond to the -occurrence of an interrupt in their own unique fashion. In -addition, each processor type provides a control mechanism to -allow the proper handling of an interrupt. The processor -dependent response to the interrupt modifies the execution state -and results in the modification of the execution stream. This -modification usually requires that an interrupt handler utilize -the provided control mechanisms to return to the normal -processing stream. Although RTEMS hides many of the processor -dependent details of interrupt processing, it is important to -understand how the RTEMS interrupt manager is mapped onto the -processor's unique architecture. Discussed in this chapter are -the the processor's response and control mechanisms as they -pertain to RTEMS. - -@section Vectoring of Interrupt Handler - -Although the i386 supports multiple privilege levels, -RTEMS and all user software executes at privilege level 0. This -decision was made by the RTEMS designers to enhance -compatibility with processors which do not provide sophisticated -protection facilities like those of the i386. This decision -greatly simplifies the discussion of i386 processing, as one -need only consider interrupts without privilege transitions. - -Upon receipt of an interrupt the i386 automatically -performs the following actions: - -@itemize @bullet -@item pushes the EFLAGS register - -@item pushes the far address of the interrupted instruction - -@item vectors to the interrupt service routine (ISR). -@end itemize - -A nested interrupt is processed similarly by the -i386. - -@section Interrupt Stack Frame - -The structure of the Interrupt Stack Frame for the -i386 which is placed on the interrupt stack by the processor in -response to an interrupt is as follows: - -@ifset use-ascii -@example -@group - +----------------------+ - | Old EFLAGS Register | ESP+8 - +----------+-----------+ - | UNUSED | Old CS | ESP+4 - +----------+-----------+ - | Old EIP | ESP - +----------------------+ -@end group -@end example -@end ifset - -@ifset use-tex -@sp 1 -@tex -\centerline{\vbox{\offinterlineskip\halign{ -\strut\vrule#& -\hbox to 1.00in{\enskip\hfil#\hfil}& -\vrule#& -\hbox to 1.00in{\enskip\hfil#\hfil}& -\vrule#& -\hbox to 0.75in{\enskip\hfil#\hfil} -\cr -\multispan{4}\hrulefill\cr -& \multispan{3} Old EFLAGS Register\quad&&ESP+8\cr -\multispan{4}\hrulefill\cr -&UNUSED &&Old CS &&ESP+4\cr -\multispan{4}\hrulefill\cr -& \multispan{3} Old EIP && ESP\cr -\multispan{4}\hrulefill\cr -}}\hfil} -@end tex -@end ifset - -@ifset use-html -@html -<CENTER> - <TABLE COLS=3 WIDTH="40%" BORDER=2> -<TR><TD ALIGN=center COLSPAN=2><STRONG>Old EFLAGS Register</STRONG></TD> - <TD ALIGN=center>0x0</TD></TR> -<TR><TD ALIGN=center><STRONG>UNUSED</STRONG></TD> - <TD ALIGN=center><STRONG>Old CS</STRONG></TD> - <TD ALIGN=center>0x2</TD></TR> -<TR><TD ALIGN=center COLSPAN=2><STRONG>Old EIP</STRONG></TD> - <TD ALIGN=center>0x4</TD></TR> - </TABLE> -</CENTER> -@end html -@end ifset - -@section Interrupt Levels - -Although RTEMS supports 256 interrupt levels, the -i386 only supports two -- enabled and disabled. Interrupts are -enabled when the interrupt-enable flag (IF) in the extended -flags (EFLAGS) is set. Conversely, interrupt processing is -inhibited when the IF is cleared. During a non-maskable -interrupt, all other interrupts, including other non-maskable -ones, are inhibited. - -RTEMS interrupt levels 0 and 1 such that level zero -(0) indicates that interrupts are fully enabled and level one -that interrupts are disabled. All other RTEMS interrupt levels -are undefined and their behavior is unpredictable. - -@section Disabling of Interrupts by RTEMS - -During the execution of directive calls, critical -sections of code may be executed. When these sections are -encountered, RTEMS disables interrupts before the execution of -this section and restores them to the previous level upon -completion of the section. RTEMS has been optimized to insure -that interrupts are disabled for less than RTEMS_MAXIMUM_DISABLE_PERIOD -microseconds on a RTEMS_MAXIMUM_DISABLE_PERIOD_MHZ Mhz i386 with zero -wait states. These numbers will vary based the number of wait states -and processor speed present on the target board. [NOTE: The maximum -period with interrupts disabled within RTEMS was last calculated for -Release RTEMS_RELEASE_FOR_MAXIMUM_DISABLE_PERIOD.] - -Non-maskable interrupts (NMI) cannot be disabled, and -ISRs which execute at this level MUST NEVER issue RTEMS system -calls. If a directive is invoked, unpredictable results may -occur due to the inability of RTEMS to protect its critical -sections. However, ISRs that make no system calls may safely -execute as non-maskable interrupts. - -@section Interrupt Stack - -The i386 family does not support a dedicated hardware -interrupt stack. On this processor, RTEMS allocates and manages -a dedicated interrupt stack. As part of vectoring a non-nested -interrupt service routine, RTEMS switches from the stack of the -interrupted task to a dedicated interrupt stack. When a -non-nested interrupt returns, RTEMS switches back to the stack -of the interrupted stack. The current stack pointer is not -altered by RTEMS on nested interrupt. - -Without a dedicated interrupt stack, every task in -the system MUST have enough stack space to accommodate the worst -case stack usage of that particular task and the interrupt -service routines COMBINED. By supporting a dedicated interrupt -stack, RTEMS significantly lowers the stack requirements for -each task. - -RTEMS allocates the dedicated interrupt stack from -the Workspace Area. The amount of memory allocated for the -interrupt stack is determined by the interrupt_stack_size field -in the CPU Configuration Table. - |