[PATCH 21/30] microblaze_mmu_v1: Add MMU related exceptions handling

monstr
2009-04-27T09:53:56Z

From: Michal Simek <monstr@monstr.eu>

Signed-off-by: Michal Simek <monstr@monstr.eu>
---
arch/microblaze/kernel/exceptions.c | 43 +++++++++++++++++++++++++++++-----
1 files changed, 36 insertions(+), 7 deletions(-)

diff --git a/arch/microblaze/kernel/exceptions.c b/arch/microblaze/kernel/exceptions.c
index 4a8a406..38be9fa 100644
--- a/arch/microblaze/kernel/exceptions.c
+++ b/arch/microblaze/kernel/exceptions.c
@@ -21,9 +21,9 @@

#include <asm/exceptions.h>
#include <asm/entry.h> /* For KM CPU var */
-#include <asm/uaccess.h>
-#include <asm/errno.h>
-#include <asm/ptrace.h>
+#include <linux/uaccess.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
#include <asm/current.h>

#define MICROBLAZE_ILL_OPCODE_EXCEPTION 0x02
@@ -66,6 +66,11 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
int fsr, int addr)
{
+#ifdef CONFIG_MMU
+ int code;
+ addr = regs->pc;
+#endif
+
#if 0
printk(KERN_WARNING "Exception %02x in %s mode, FSR=%08x PC=%08x ESR=%08x\n",
type, user_mode(regs) ? "user" : "kernel", fsr,
@@ -74,7 +79,13 @@ asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,

switch (type & 0x1F) {
case MICROBLAZE_ILL_OPCODE_EXCEPTION:
- _exception(SIGILL, regs, ILL_ILLOPC, addr);
+ if (user_mode(regs)) {
+ printk(KERN_WARNING "Illegal opcode exception in user mode.\n");
+ _exception(SIGILL, regs, ILL_ILLOPC, addr);
+ return;
+ }
+ printk(KERN_WARNING "Illegal opcode exception in kernel mode.\n");
+ die("opcode exception", regs, SIGBUS);
break;
case MICROBLAZE_IBUS_EXCEPTION:
if (user_mode(regs)) {
@@ -95,11 +106,16 @@ asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
die("bus exception", regs, SIGBUS);
break;
case MICROBLAZE_DIV_ZERO_EXCEPTION:
- printk(KERN_WARNING "Divide by zero exception\n");
- _exception(SIGILL, regs, ILL_ILLOPC, addr);
+ if (user_mode(regs)) {
+ printk(KERN_WARNING "Divide by zero exception in user mode\n");
+ _exception(SIGILL, regs, ILL_ILLOPC, addr);
+ return;
+ }
+ printk(KERN_WARNING "Divide by zero exception in kernel mode.\n");
+ die("Divide by exception", regs, SIGBUS);
break;
-
case MICROBLAZE_FPU_EXCEPTION:
+ printk(KERN_WARNING "FPU exception\n");
/* IEEE FP exception */
/* I removed fsr variable and use code var for storing fsr */
if (fsr & FSR_IO)
@@ -115,7 +131,20 @@ asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
_exception(SIGFPE, regs, fsr, addr);
break;

+#ifdef CONFIG_MMU
+ case MICROBLAZE_PRIVILEG_EXCEPTION:
+ printk(KERN_WARNING "Privileg exception\n");
+ /* "brk r0,r0" - used as debug breakpoint */
+ if (get_user(code, (unsigned long *)regs->pc) == 0
+ && code == 0x980c0000) {
+ _exception(SIGTRAP, regs, TRAP_BRKPT, addr);
+ } else {
+ _exception(SIGILL, regs, ILL_PRVOPC, addr);
+ }
+ break;
+#endif
default:
+ /* FIXME what to do in unexpected exception */
printk(KERN_WARNING "Unexpected exception %02x "
"PC=%08x in %s mode\n", type, (unsigned int) addr,
kernel_mode(regs) ? "kernel" : "user");
--
1.5.5.1