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authorRalf Baechle <ralf@linux-mips.org>2000-02-04 07:40:19 +0000
committerRalf Baechle <ralf@linux-mips.org>2000-02-04 07:40:19 +0000
commit33263fc5f9ac8e8cb2b22d06af3ce5ac1dd815e4 (patch)
tree2d1b86a40bef0958a68cf1a2eafbeb0667a70543 /arch/ppc/kernel/align.c
parent216f5f51aa02f8b113aa620ebc14a9631a217a00 (diff)
Merge with Linux 2.3.32.
Diffstat (limited to 'arch/ppc/kernel/align.c')
-rw-r--r--arch/ppc/kernel/align.c52
1 files changed, 47 insertions, 5 deletions
diff --git a/arch/ppc/kernel/align.c b/arch/ppc/kernel/align.c
index 6a20863c5..7f6340261 100644
--- a/arch/ppc/kernel/align.c
+++ b/arch/ppc/kernel/align.c
@@ -1,9 +1,13 @@
/*
* align.c - handle alignment exceptions for the Power PC.
*
- * Paul Mackerras August 1996.
- * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au).
+ * Copyright (c) 1996 Paul Mackerras <paulus@cs.anu.edu.au>
+ * Copyright (c) 1998-1999 TiVo, Inc.
+ * PowerPC 403GCX modifications.
+ * Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu>
+ * PowerPC 403GCX/405GP modifications.
*/
+#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <asm/ptrace.h>
@@ -16,6 +20,13 @@ struct aligninfo {
unsigned char flags;
};
+#if defined(CONFIG_4xx)
+#define OPCD(inst) (((inst) & 0xFC000000) >> 26)
+#define RS(inst) (((inst) & 0x03E00000) >> 21)
+#define RA(inst) (((inst) & 0x001F0000) >> 16)
+#define IS_DFORM(code) ((code) >= 32 && (code) <= 47)
+#endif
+
#define INVALID { 0, 0 }
#define LD 1 /* load */
@@ -170,6 +181,9 @@ int
fix_alignment(struct pt_regs *regs)
{
int instr, nb, flags;
+#if defined(CONFIG_4xx)
+ int opcode, f1, f2, f3;
+#endif
int i, t;
int reg, areg;
unsigned char *addr;
@@ -180,13 +194,42 @@ fix_alignment(struct pt_regs *regs)
unsigned char v[8];
} data;
+#if defined(CONFIG_4xx)
+ /* The 4xx-family processors have no DSISR register,
+ * so we emulate it.
+ */
+
+ instr = *((unsigned int *)regs->nip);
+ opcode = OPCD(instr);
+ reg = RS(instr);
+ areg = RA(instr);
+
+ if (IS_DFORM(opcode)) {
+ f1 = 0;
+ f2 = (instr & 0x04000000) >> 26;
+ f3 = (instr & 0x78000000) >> 27;
+ } else {
+ f1 = (instr & 0x00000006) >> 1;
+ f2 = (instr & 0x00000040) >> 6;
+ f3 = (instr & 0x00000780) >> 7;
+ }
+
+ instr = ((f1 << 5) | (f2 << 4) | f3);
+#else
+ reg = (regs->dsisr >> 5) & 0x1f; /* source/dest register */
+ areg = regs->dsisr & 0x1f; /* register to update */
instr = (regs->dsisr >> 10) & 0x7f;
+#endif
nb = aligninfo[instr].len;
if (nb == 0)
return 0; /* too hard or invalid instruction bits */
flags = aligninfo[instr].flags;
- addr = (unsigned char *) regs->dar;
- reg = (regs->dsisr >> 5) & 0x1f; /* source/dest register */
+
+ /* For the 4xx-family processors, the 'dar' field of the
+ * pt_regs structure is overloaded and is really from the DEAR.
+ */
+
+ addr = (unsigned char *)regs->dar;
/* Verify the address of the operand */
if (user_mode(regs)) {
@@ -280,7 +323,6 @@ fix_alignment(struct pt_regs *regs)
}
if (flags & U) {
- areg = regs->dsisr & 0x1f; /* register to update */
regs->gpr[areg] = regs->dar;
}