freebsd-skq/sys/i386/isa/apic_ipl.s
Steve Passe 886e789627 The last of the encapsolation of cpl/spl/ipending things into a critical
region protected by the simplelock 'cpl_lock'.

Notes:

 - this code is currently controlled on a section by section basis with
   defines in machine/param.h.  All sections are currently enabled.

 - this code is not as clean as I would like, but that can wait till later.

 - the "giant lock" still surrounds most instances of this "cpl region".
   I still have to do the code that arbitrates setting cpl between the
   top and bottom halves of the kernel.

 - the possibility of deadlock exists, I am committing the code at this
   point so as to exercise it and detect any such cases B4 the "giant lock"
   is removed.
1997-08-24 00:05:37 +00:00

503 lines
12 KiB
ArmAsm

/*-
* Copyright (c) 1997, by Steve Passe
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. The name of the developer may NOT be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $Id: apic_ipl.s,v 1.28 1997/08/23 05:15:12 smp Exp smp $
*/
#if defined(SMP) && defined(REAL_AICPL)
#define AICPL_LOCK SCPL_LOCK
#define AICPL_UNLOCK SCPL_UNLOCK
#else /* SMP */
#define AICPL_LOCK
#define AICPL_UNLOCK
#endif /* SMP */
.data
ALIGN_DATA
/* current INTerrupt level */
.globl _cil
_cil: .long 0
/* this allows us to change the 8254 APIC pin# assignment */
.globl _Xintr8254
_Xintr8254:
.long _Xintr7
/* used by this file, microtime.s and clock.c */
.globl _mask8254
_mask8254:
.long 0
/* */
.globl _vec
_vec:
.long vec0, vec1, vec2, vec3, vec4, vec5, vec6, vec7
.long vec8, vec9, vec10, vec11, vec12, vec13, vec14, vec15
.long vec16, vec17, vec18, vec19, vec20, vec21, vec22, vec23
/*
* Note:
* This is the UP equivilant of _imen.
* It is OPAQUE, and must NOT be accessed directly.
* It MUST be accessed along with the IO APIC as a 'critical region'.
* Accessed by:
* INTREN()
* INTRDIS()
* MAYBE_MASK_IRQ
* MAYBE_UNMASK_IRQ
* imen_dump()
*/
.align 2 /* MUST be 32bit aligned */
.globl _apic_imen
_apic_imen:
.long HWI_MASK
/*
*
*/
.text
SUPERALIGN_TEXT
/*
* Interrupt priority mechanism
* -- soft splXX masks with group mechanism (cpl)
* -- h/w masks for currently active or unused interrupts (imen)
* -- ipending = active interrupts currently masked by cpl
*/
ENTRY(splz)
/*
* The caller has restored cpl and checked that (ipending & ~cpl)
* is nonzero. We have to repeat the check since if there is an
* interrupt while we're looking, _doreti processing for the
* interrupt will handle all the unmasked pending interrupts
* because we restored early. We're repeating the calculation
* of (ipending & ~cpl) anyway so that the caller doesn't have
* to pass it, so this only costs one "jne". "bsfl %ecx,%ecx"
* is undefined when %ecx is 0 so we can't rely on the secondary
* btrl tests.
*/
AICPL_LOCK
movl _cpl,%eax
splz_next:
/*
* We don't need any locking here. (ipending & ~cpl) cannot grow
* while we're looking at it - any interrupt will shrink it to 0.
*/
movl %eax,%ecx
notl %ecx /* set bit = unmasked level */
andl _ipending,%ecx /* set bit = unmasked pending INT */
jne splz_unpend
AICPL_UNLOCK
ret
ALIGN_TEXT
splz_unpend:
bsfl %ecx,%ecx
lock
btrl %ecx, _ipending
jnc splz_next
movl ihandlers(,%ecx,4),%edx
testl %edx,%edx
je splz_next /* "can't happen" */
cmpl $NHWI,%ecx
jae splz_swi
AICPL_UNLOCK
/*
* We would prefer to call the intr handler directly here but that
* doesn't work for badly behaved handlers that want the interrupt
* frame. Also, there's a problem determining the unit number.
* We should change the interface so that the unit number is not
* determined at config time.
*/
jmp *_vec(,%ecx,4)
ALIGN_TEXT
splz_swi:
cmpl $SWI_AST,%ecx
je splz_next /* "can't happen" */
pushl %eax
orl imasks(,%ecx,4),%eax
movl %eax,_cpl
AICPL_UNLOCK
call %edx
AICPL_LOCK
popl %eax
movl %eax,_cpl
jmp splz_next
/*
* Fake clock interrupt(s) so that they appear to come from our caller instead
* of from here, so that system profiling works.
* XXX do this more generally (for all vectors; look up the C entry point).
* XXX frame bogusness stops us from just jumping to the C entry point.
*/
/*
* generic vector function for 8254 clock
*/
ALIGN_TEXT
.globl _vec8254
_vec8254:
popl %eax /* return address */
pushfl
pushl $KCSEL
pushl %eax
movl _mask8254, %eax /* lazy masking */
notl %eax
cli
lock /* MP-safe */
andl %eax, iactive
MEXITCOUNT
movl _Xintr8254, %eax
jmp %eax /* XXX might need _Xfastintr# */
/*
* generic vector function for RTC clock
*/
ALIGN_TEXT
vec8:
popl %eax
pushfl
pushl $KCSEL
pushl %eax
cli
lock /* MP-safe */
andl $~IRQ_BIT(8), iactive /* lazy masking */
MEXITCOUNT
jmp _Xintr8 /* XXX might need _Xfastintr8 */
/*
* The 'generic' vector stubs.
*/
#define BUILD_VEC(irq_num) \
ALIGN_TEXT ; \
__CONCAT(vec,irq_num): ; \
popl %eax ; \
pushfl ; \
pushl $KCSEL ; \
pushl %eax ; \
cli ; \
lock ; /* MP-safe */ \
andl $~IRQ_BIT(irq_num), iactive ; /* lazy masking */ \
MEXITCOUNT ; \
jmp __CONCAT(_Xintr,irq_num)
BUILD_VEC(0)
BUILD_VEC(1)
BUILD_VEC(2)
BUILD_VEC(3)
BUILD_VEC(4)
BUILD_VEC(5)
BUILD_VEC(6)
BUILD_VEC(7)
/* IRQ8 is special case, done above */
BUILD_VEC(9)
BUILD_VEC(10)
BUILD_VEC(11)
BUILD_VEC(12)
BUILD_VEC(13)
BUILD_VEC(14)
BUILD_VEC(15)
BUILD_VEC(16) /* 8 additional INTs in IO APIC */
BUILD_VEC(17)
BUILD_VEC(18)
BUILD_VEC(19)
BUILD_VEC(20)
BUILD_VEC(21)
BUILD_VEC(22)
BUILD_VEC(23)
/******************************************************************************
* XXX FIXME: figure out where these belong.
*/
/* this nonsense is to verify that masks ALWAYS have 1 and only 1 bit set */
#define QUALIFY_MASKS_NOT
#ifdef QUALIFY_MASKS
#define QUALIFY_MASK \
btrl %ecx, %eax ; \
andl %eax, %eax ; \
jz 1f ; \
pushl $bad_mask ; \
call _panic ; \
1:
bad_mask: .asciz "bad mask"
#else
#define QUALIFY_MASK
#endif
/*
* MULTIPLE_IOAPICSXXX: cannot assume apic #0 in the following function.
* (soon to be) MP-safe function to clear ONE INT mask bit.
* The passed arg is a 32bit u_int MASK.
* It sets the associated bit in _apic_imen.
* It sets the mask bit of the associated IO APIC register.
*/
ENTRY(INTREN)
pushfl /* save state of EI flag */
cli /* prevent recursion */
IMASK_LOCK /* enter critical reg */
movl 8(%esp), %eax /* mask into %eax */
bsfl %eax, %ecx /* get pin index */
btrl %ecx, _apic_imen /* update _apic_imen */
QUALIFY_MASK
leal 16(,%ecx,2), %ecx /* calculate register index */
movl $0, %edx /* XXX FIXME: APIC # */
movl _ioapic(,%edx,4), %edx /* %edx holds APIC base address */
movl %ecx, (%edx) /* write the target register index */
movl 16(%edx), %eax /* read the target register data */
andl $~IOART_INTMASK, %eax /* clear mask bit */
movl %eax, 16(%edx) /* write the APIC register data */
IMASK_UNLOCK /* exit critical reg */
popfl /* restore old state of EI flag */
ret
/*
* MULTIPLE_IOAPICSXXX: cannot assume apic #0 in the following function.
* (soon to be) MP-safe function to set ONE INT mask bit.
* The passed arg is a 32bit u_int MASK.
* It clears the associated bit in _apic_imen.
* It clears the mask bit of the associated IO APIC register.
*/
ENTRY(INTRDIS)
pushfl /* save state of EI flag */
cli /* prevent recursion */
IMASK_LOCK /* enter critical reg */
movl 8(%esp), %eax /* mask into %eax */
bsfl %eax, %ecx /* get pin index */
btsl %ecx, _apic_imen /* update _apic_imen */
QUALIFY_MASK
leal 16(,%ecx,2), %ecx /* calculate register index */
movl $0, %edx /* XXX FIXME: APIC # */
movl _ioapic(,%edx,4), %edx /* %edx holds APIC base address */
movl %ecx, (%edx) /* write the target register index */
movl 16(%edx), %eax /* read the target register data */
orl $IOART_INTMASK, %eax /* set mask bit */
movl %eax, 16(%edx) /* write the APIC register data */
IMASK_UNLOCK /* exit critical reg */
popfl /* restore old state of EI flag */
ret
/******************************************************************************
*
*/
/*
* void write_ioapic_mask(int apic, u_int mask);
*/
#define _INT_MASK 0x00010000
#define _PIN_MASK 0x00ffffff
#define _OLD_ESI 0(%esp)
#define _OLD_EBX 4(%esp)
#define _RETADDR 8(%esp)
#define _APIC 12(%esp)
#define _MASK 16(%esp)
.align 2
write_ioapic_mask:
pushl %ebx /* scratch */
pushl %esi /* scratch */
movl _apic_imen, %ebx
xorl _MASK, %ebx /* %ebx = _apic_imen ^ mask */
andl $_PIN_MASK, %ebx /* %ebx = _apic_imen & 0x00ffffff */
jz all_done /* no change, return */
movl _APIC, %esi /* APIC # */
movl _ioapic(,%esi,4), %esi /* %esi holds APIC base address */
next_loop: /* %ebx = diffs, %esi = APIC base */
bsfl %ebx, %ecx /* %ecx = index if 1st/next set bit */
jz all_done
btrl %ecx, %ebx /* clear this bit in diffs */
leal 16(,%ecx,2), %edx /* calculate register index */
movl %edx, (%esi) /* write the target register index */
movl 16(%esi), %eax /* read the target register data */
btl %ecx, _MASK /* test for mask or unmask */
jnc clear /* bit is clear */
orl $_INT_MASK, %eax /* set mask bit */
jmp write
clear: andl $~_INT_MASK, %eax /* clear mask bit */
write: movl %eax, 16(%esi) /* write the APIC register data */
jmp next_loop /* try another pass */
all_done:
popl %esi
popl %ebx
ret
#undef _OLD_ESI
#undef _OLD_EBX
#undef _RETADDR
#undef _APIC
#undef _MASK
#undef _PIN_MASK
#undef _INT_MASK
#ifdef oldcode
_INTREN:
movl _apic_imen, %eax
notl %eax /* mask = ~mask */
andl _apic_imen, %eax /* %eax = _apic_imen & ~mask */
pushl %eax /* new (future) _apic_imen value */
pushl $0 /* APIC# arg */
call write_ioapic_mask /* modify the APIC registers */
addl $4, %esp /* remove APIC# arg from stack */
popl _apic_imen /* _apic_imen |= mask */
ret
_INTRDIS:
movl _apic_imen, %eax
orl 4(%esp), %eax /* %eax = _apic_imen | mask */
pushl %eax /* new (future) _apic_imen value */
pushl $0 /* APIC# arg */
call write_ioapic_mask /* modify the APIC registers */
addl $4, %esp /* remove APIC# arg from stack */
popl _apic_imen /* _apic_imen |= mask */
ret
#endif /* oldcode */
#ifdef ready
/*
* u_int read_io_apic_mask(int apic);
*/
ALIGN_TEXT
read_io_apic_mask:
ret
/*
* Set INT mask bit for each bit set in 'mask'.
* Ignore INT mask bit for all others.
*
* void set_io_apic_mask(apic, u_int32_t bits);
*/
ALIGN_TEXT
set_io_apic_mask:
ret
/*
* void set_ioapic_maskbit(int apic, int bit);
*/
ALIGN_TEXT
set_ioapic_maskbit:
ret
/*
* Clear INT mask bit for each bit set in 'mask'.
* Ignore INT mask bit for all others.
*
* void clr_io_apic_mask(int apic, u_int32_t bits);
*/
ALIGN_TEXT
clr_io_apic_mask:
ret
/*
* void clr_ioapic_maskbit(int apic, int bit);
*/
ALIGN_TEXT
clr_ioapic_maskbit:
ret
#endif /** ready */
/******************************************************************************
*
*/
/*
* u_int io_apic_write(int apic, int select);
*/
ENTRY(io_apic_read)
movl 4(%esp), %ecx /* APIC # */
movl _ioapic(,%ecx,4), %edx /* APIC base register address */
movl 8(%esp), %eax /* target register index */
movl %eax, (%edx) /* write the target register index */
movl 16(%edx), %eax /* read the APIC register data */
ret /* %eax = register value */
/*
* void io_apic_write(int apic, int select, int value);
*/
ENTRY(io_apic_write)
movl 4(%esp), %ecx /* APIC # */
movl _ioapic(,%ecx,4), %edx /* APIC base register address */
movl 8(%esp), %eax /* target register index */
movl %eax, (%edx) /* write the target register index */
movl 12(%esp), %eax /* target register value */
movl %eax, 16(%edx) /* write the APIC register data */
ret /* %eax = void */
/*
* Send an EOI to the local APIC.
*/
ENTRY(apic_eoi)
movl $0, _lapic+0xb0
ret