d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Move the exception vector table (so-called "page0" data) into exception.S

Browse Source 
and eliminate vectors.S.  All low-level exception handling is now
consolidated into exception.S.

Along with moving the default FIQ handler, change it to disable FIQs
before returning.  An FIQ should never happen, but if it does, it's got
to be disabled as part of ignoring it.

In general, we have hand-wavy support for FIQs that probably hasn't been
used for 10 years and probably doesn't work (almost certainly doesn't
work for SMP because it only updates the vector on the current cpu).  This
change doesn't really make the overall situation any better or worse.
This commit is contained in:
Ian Lepore 2014-03-10 19:36:26 +00:00
parent 5e4e1d4995
commit 0e255c3294
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=262980
5 changed files with 74 additions and 125 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

70
sys/arm/arm/exception.S
View File

@ -148,7 +148,7 @@ _C_LABEL(data_abort_handler_address):
END(data_abort_entry)
/*
* address_exception_entry:
* addr_exception_entry:
*
* Handler for the Address Exception exception.
*
@ -156,17 +156,17 @@ END(data_abort_entry)
* print a warning message to the console and then treat
* it like a Data Abort.
*/
ASENTRY_NP(address_exception_entry)
ASENTRY_NP(addr_exception_entry)
mrs r1, cpsr
mrs r2, spsr
mov r3, lr
adr r0, Laddress_exception_msg
adr r0, Laddr_exception_msg
bl _C_LABEL(printf) /* XXX CLOBBERS LR!! */
b data_abort_entry
Laddress_exception_msg:
Laddr_exception_msg:
.asciz "Address Exception CPSR=0x%08x SPSR=0x%08x LR=0x%08x\n"
.balign 4
END(address_exception_entry)
END(addr_exception_entry)
/*
* General exception exit handler
@ -234,3 +234,63 @@ Lundefined_handler_address:
_C_LABEL(undefined_handler_address):
.word undefinedinstruction_bounce
/*
* Entry point for FIQ interrupts.
*
* We don't currently support FIQ handlers very much. Something can
* install itself in the FIQ vector using code (that may or may not work
* these days) in fiq.c. If nobody does that and an FIQ happens, this
* default handler just disables FIQs and otherwise ignores it.
*/
ASENTRY_NP(fiq_entry)
mrs r8, cpsr /* FIQ handling isn't supported, */
bic r8, #(F32_bit) /* just disable FIQ and return. */
msr cpsr_c, r8 /* The r8 we trash here is the */
subs pc, lr, #4 /* banked FIQ-mode r8. */
END(fiq_entry)
/*
* page0 and page0_data -- An image of the ARM vectors which is copied to
* the ARM vectors page (high or low) as part of CPU initialization. The
* code that does the copy assumes that page0_data holds one 32-bit word
* of data for each of the predefined ARM vectors. It also assumes that
* page0_data follows the vectors in page0, but other stuff can appear
* between the two. We currently leave room between the two for some fiq
* handler code to be copied in.
*/
.global _C_LABEL(page0), _C_LABEL(page0_data)
_C_LABEL(page0):
ldr pc, .Lreset_entry
ldr pc, .Lundefined_entry
ldr pc, .Lswi_entry
ldr pc, .Lprefetch_abort_entry
ldr pc, .Ldata_abort_entry
ldr pc, .Laddr_exception_entry
ldr pc, .Lirq_entry
.fiqv: ldr pc, .Lfiq_entry
.space 256 /* room for some fiq handler code */
_C_LABEL(page0_data):
.Lreset_entry: .word reset_entry
.Lundefined_entry: .word undefined_entry
.Lswi_entry: .word swi_entry
.Lprefetch_abort_entry: .word prefetch_abort_entry
.Ldata_abort_entry: .word data_abort_entry
.Laddr_exception_entry: .word addr_exception_entry
.Lirq_entry: .word irq_entry
.Lfiq_entry: .word fiq_entry
/*
* These items are used by the code in fiq.c to install what it calls the
* "null" handler. It's actually our default vector entry that just jumps
* to the default handler which just disables FIQs and returns.
*/
.global _C_LABEL(fiq_nullhandler_code), _C_LABEL(fiq_nullhandler_size)
_C_LABEL(fiq_nullhandler_code):
.word .fiqv
_C_LABEL(fiq_nullhandler_size):
.word 4

14
sys/arm/arm/fiq.c
View File

@ -51,8 +51,8 @@ __FBSDID("$FreeBSD$");
TAILQ_HEAD(, fiqhandler) fiqhandler_stack =
TAILQ_HEAD_INITIALIZER(fiqhandler_stack);
extern char fiqvector[];
extern char fiq_nullhandler[], fiq_nullhandler_end[];
extern char *fiq_nullhandler_code;
extern uint32_t fiq_nullhandler_size;
#define IRQ_BIT I32_bit
#define FIQ_BIT F32_bit
@ -61,6 +61,9 @@ extern char fiq_nullhandler[], fiq_nullhandler_end[];
* fiq_installhandler:
*
* Actually install the FIQ handler down at the FIQ vector.
*
* The FIQ vector is fixed by the hardware definition as the
* seventh 32-bit word in the vector page.
*
* Note: If the FIQ is invoked via an extra layer of
* indirection, the actual FIQ code store lives in the
@ -70,11 +73,13 @@ extern char fiq_nullhandler[], fiq_nullhandler_end[];
static void
fiq_installhandler(void *func, size_t size)
{
const uint32_t fiqvector = 7 * sizeof(uint32_t);
#if !defined(__ARM_FIQ_INDIRECT)
vector_page_setprot(VM_PROT_READ|VM_PROT_WRITE);
#endif
memcpy(vector_page + fiqvector, func, size);
memcpy((void *)(vector_page + fiqvector), func, size);
#if !defined(__ARM_FIQ_INDIRECT)
vector_page_setprot(VM_PROT_READ);
@ -159,8 +164,7 @@ fiq_release(struct fiqhandler *fh)
if (TAILQ_FIRST(&fiqhandler_stack) == NULL) {
/* Copy the NULL handler back down into the vector. */
fiq_installhandler(fiq_nullhandler,
(size_t)(fiq_nullhandler_end - fiq_nullhandler));
fiq_installhandler(fiq_nullhandler_code, fiq_nullhandler_size);
/* Make sure FIQs are disabled when we return. */
oldirqstate |= FIQ_BIT;

10
sys/arm/arm/fiq_subr.S
View File

@ -91,13 +91,3 @@ ENTRY(fiq_setregs)
RET
END(fiq_setregs)
/*
* fiq_nullhandler:
*
* Null handler copied down to the FIQ vector when the last
* FIQ handler is removed.
*/
.global _C_LABEL(fiq_nullhandler), _C_LABEL(fiq_nullhandler_end)
_C_LABEL(fiq_nullhandler):
subs pc, lr, #4
_C_LABEL(fiq_nullhandler_end):

104
sys/arm/arm/vectors.S
View File

@ -1,104 +0,0 @@
/* $NetBSD: vectors.S,v 1.4 2002/08/17 16:36:32 thorpej Exp $ */
/*-
* Copyright (C) 1994-1997 Mark Brinicombe
* Copyright (C) 1994 Brini
* 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. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Brini.
* 4. The name of Brini may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY BRINI ``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 BRINI 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.
*
*/
#include <machine/asm.h>
__FBSDID("$FreeBSD$");
/*
* These are the exception vectors copied down to page 0.
*
* Note that FIQs are special; rather than using a level of
* indirection, we actually copy the FIQ code down into the
* vector page.
*/
.text
.align 0
.global _C_LABEL(page0), _C_LABEL(page0_data), _C_LABEL(page0_end)
.global _C_LABEL(fiqvector)
_C_LABEL(page0):
ldr pc, .Lreset_target
ldr pc, .Lundefined_target
ldr pc, .Lswi_target
ldr pc, .Lprefetch_abort_target
ldr pc, .Ldata_abort_target
ldr pc, .Laddress_exception_target
ldr pc, .Lirq_target
#ifdef __ARM_FIQ_INDIRECT
ldr pc, .Lfiq_target
#else
.Lfiqvector:
.set _C_LABEL(fiqvector), . - _C_LABEL(page0)
subs pc, lr, #4
.org .Lfiqvector + 0x100
#endif
_C_LABEL(page0_data):
.Lreset_target:
.word reset_entry
.Lundefined_target:
.word undefined_entry
.Lswi_target:
.word swi_entry
.Lprefetch_abort_target:
.word prefetch_abort_entry
.Ldata_abort_target:
.word data_abort_entry
.Laddress_exception_target:
.word address_exception_entry
.Lirq_target:
.word irq_entry
#ifdef __ARM_FIQ_INDIRECT
.Lfiq_target:
.word _C_LABEL(fiqvector)
#else
.word 0 /* pad it out */
#endif
_C_LABEL(page0_end):
#ifdef __ARM_FIQ_INDIRECT
.data
.align 0
_C_LABEL(fiqvector):
subs pc, lr, #4
.org _C_LABEL(fiqvector) + 0x100
#endif

1
sys/conf/files.arm
View File

@ -50,7 +50,6 @@ arm/arm/sys_machdep.c standard
arm/arm/trap.c standard
arm/arm/uio_machdep.c standard
arm/arm/undefined.c standard
arm/arm/vectors.S standard
arm/arm/vm_machdep.c standard
arm/arm/vfp.c standard
board_id.h standard \