freebsd-skq/sys/i386/isa/vector.s
jhb 2463f40fc3 Introduce a standard name for the lock protecting an interrupt controller
and it's associated state variables: icu_lock with the name "icu".  This
renames the imen_mtx for x86 SMP, but also uses the lock to protect
access to the 8259 PIC on x86 UP.  This also adds an appropriate lock to
the various Alpha chipsets which fixes problems with Alpha SMP machines
dropping interrupts with an SMP kernel.
2001-12-20 23:48:31 +00:00

109 lines
3.4 KiB
ArmAsm

/*
* from: vector.s, 386BSD 0.1 unknown origin
* $FreeBSD$
*/
/*
* modified for PC98 by Kakefuda
*/
#include "opt_auto_eoi.h"
#include <i386/isa/icu.h>
#ifdef PC98
#include <pc98/pc98/pc98.h>
#else
#include <i386/isa/isa.h>
#endif
#include <i386/isa/intr_machdep.h>
#define FAST_INTR_HANDLER_USES_ES 1
#ifdef FAST_INTR_HANDLER_USES_ES
#define ACTUALLY_PUSHED 1
#define MAYBE_MOVW_AX_ES movw %ax,%es
#define MAYBE_POPL_ES popl %es
#define MAYBE_PUSHL_ES pushl %es
#else
/*
* We can usually skip loading %es for fastintr handlers. %es should
* only be used for string instructions, and fastintr handlers shouldn't
* do anything slow enough to justify using a string instruction.
*/
#define ACTUALLY_PUSHED 0
#define MAYBE_MOVW_AX_ES
#define MAYBE_POPL_ES
#define MAYBE_PUSHL_ES
#endif
.data
ALIGN_DATA
/*
* Interrupt counters and names for export to vmstat(8) and friends.
*
* XXX this doesn't really belong here; everything except the labels
* for the endpointers is almost machine-independent.
*/
.globl intrcnt, eintrcnt
intrcnt:
.space INTRCNT_COUNT * 4
eintrcnt:
.globl intrnames, eintrnames
intrnames:
.space INTRCNT_COUNT * 16
eintrnames:
.text
/*
* Macros for interrupt interrupt entry, call to handler, and exit.
*
* XXX - the interrupt frame is set up to look like a trap frame. This is
* usually a waste of time. The only interrupt handlers that want a frame
* are the clock handler (it wants a clock frame), the npx handler (it's
* easier to do right all in assembler). The interrupt return routine
* needs a trap frame for rare AST's (it could easily convert the frame).
* The direct costs of setting up a trap frame are two pushl's (error
* code and trap number), an addl to get rid of these, and pushing and
* popping the call-saved regs %esi, %edi and %ebp twice, The indirect
* costs are making the driver interface nonuniform so unpending of
* interrupts is more complicated and slower (call_driver(unit) would
* be easier than ensuring an interrupt frame for all handlers. Finally,
* there are some struct copies in the npx handler and maybe in the clock
* handler that could be avoided by working more with pointers to frames
* instead of frames.
*
* XXX - should we do a cld on every system entry to avoid the requirement
* for scattered cld's?
*
* Coding notes for *.s:
*
* If possible, avoid operations that involve an operand size override.
* Word-sized operations might be smaller, but the operand size override
* makes them slower on on 486's and no faster on 386's unless perhaps
* the instruction pipeline is depleted. E.g.,
*
* Use movl to seg regs instead of the equivalent but more descriptive
* movw - gas generates an irelevant (slower) operand size override.
*
* Use movl to ordinary regs in preference to movw and especially
* in preference to movz[bw]l. Use unsigned (long) variables with the
* top bits clear instead of unsigned short variables to provide more
* opportunities for movl.
*
* If possible, use byte-sized operations. They are smaller and no slower.
*
* Use (%reg) instead of 0(%reg) - gas generates larger code for the latter.
*
* If the interrupt frame is made more flexible, INTR can push %eax first
* and decide the ipending case with less overhead, e.g., by avoiding
* loading segregs.
*/
#ifdef APIC_IO
#include "i386/isa/apic_vector.s"
#else
#include "i386/isa/icu_vector.s"
#endif /* APIC_IO */