svn commit: r262980 - in head/sys: arm/arm conf
Ian Lepore
ian at FreeBSD.org
Mon Mar 10 19:36:27 UTC 2014
Author: ian
Date: Mon Mar 10 19:36:26 2014
New Revision: 262980
URL: http://svnweb.freebsd.org/changeset/base/262980
Log:
Move the exception vector table (so-called "page0" data) into exception.S
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.
Deleted:
head/sys/arm/arm/vectors.S
Modified:
head/sys/arm/arm/exception.S
head/sys/arm/arm/fiq.c
head/sys/arm/arm/fiq_subr.S
head/sys/conf/files.arm
Modified: head/sys/arm/arm/exception.S
==============================================================================
--- head/sys/arm/arm/exception.S Mon Mar 10 18:10:09 2014 (r262979)
+++ head/sys/arm/arm/exception.S Mon Mar 10 19:36:26 2014 (r262980)
@@ -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
+
+
Modified: head/sys/arm/arm/fiq.c
==============================================================================
--- head/sys/arm/arm/fiq.c Mon Mar 10 18:10:09 2014 (r262979)
+++ head/sys/arm/arm/fiq.c Mon Mar 10 19:36:26 2014 (r262980)
@@ -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_nullh
* 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_nullh
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;
Modified: head/sys/arm/arm/fiq_subr.S
==============================================================================
--- head/sys/arm/arm/fiq_subr.S Mon Mar 10 18:10:09 2014 (r262979)
+++ head/sys/arm/arm/fiq_subr.S Mon Mar 10 19:36:26 2014 (r262980)
@@ -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):
Modified: head/sys/conf/files.arm
==============================================================================
--- head/sys/conf/files.arm Mon Mar 10 18:10:09 2014 (r262979)
+++ head/sys/conf/files.arm Mon Mar 10 19:36:26 2014 (r262980)
@@ -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 \
More information about the svn-src-all
mailing list