[PATCH] powerpc: merge align.c

This patch merges align.c, the result isn't quite what was in ppc64 nor
what was in ppc32 :) It should implement all the functionalities of both
though. Kumar, since you played with that in the past, I suppose you
have some test cases for verifying that it works properly before I dig
out the 601 machine ? :)

Since it's likely that I won't be able to test all scenario, code
inspection is much welcome.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 2 insertions, 412 deletions

diff --git a/arch/ppc/kernel/Makefile b/arch/ppc/kernel/Makefile
index 17a4da6..0bb23fc 100644
--- a/arch/ppc/kernel/Makefile
+++ b/arch/ppc/kernel/Makefile
@@ -13,7 +13,7 @@ extra-$(CONFIG_POWER4)		+= idle_power4.o
 extra-y				+= vmlinux.lds
 
 obj-y				:= entry.o traps.o idle.o time.o misc.o \
-					process.o align.o \
+					process.o \
 					setup.o \
 					ppc_htab.o
 obj-$(CONFIG_6xx)		+= l2cr.o cpu_setup_6xx.o
@@ -38,7 +38,7 @@ endif
 # These are here while we do the architecture merge
 
 else
-obj-y				:= idle.o align.o
+obj-y				:= idle.o
 obj-$(CONFIG_6xx)		+= l2cr.o cpu_setup_6xx.o
 obj-$(CONFIG_SOFTWARE_SUSPEND)	+= swsusp.o
 obj-$(CONFIG_MODULES)		+= module.o
diff --git a/arch/ppc/kernel/align.c b/arch/ppc/kernel/align.c
deleted file mode 100644
index ab398c4..0000000
--- a/arch/ppc/kernel/align.c
+++ /dev/null
@@ -1,410 +0,0 @@
-/*
- * align.c - handle alignment exceptions for the Power PC.
- *
- * 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>
-#include <asm/processor.h>
-#include <asm/uaccess.h>
-#include <asm/system.h>
-#include <asm/cache.h>
-
-struct aligninfo {
-	unsigned char len;
-	unsigned char flags;
-};
-
-#if defined(CONFIG_4xx) || defined(CONFIG_POWER4) || defined(CONFIG_BOOKE)
-#define	OPCD(inst)	(((inst) & 0xFC000000) >> 26)
-#define	RS(inst)	(((inst) & 0x03E00000) >> 21)
-#define	RA(inst)	(((inst) & 0x001F0000) >> 16)
-#define	IS_XFORM(code)	((code) == 31)
-#endif
-
-#define INVALID	{ 0, 0 }
-
-#define LD	1	/* load */
-#define ST	2	/* store */
-#define	SE	4	/* sign-extend value */
-#define F	8	/* to/from fp regs */
-#define U	0x10	/* update index register */
-#define M	0x20	/* multiple load/store */
-#define S	0x40	/* single-precision fp, or byte-swap value */
-#define SX	0x40	/* byte count in XER */
-#define HARD	0x80	/* string, stwcx. */
-
-#define DCBZ	0x5f	/* 8xx/82xx dcbz faults when cache not enabled */
-
-/*
- * The PowerPC stores certain bits of the instruction that caused the
- * alignment exception in the DSISR register.  This array maps those
- * bits to information about the operand length and what the
- * instruction would do.
- */
-static struct aligninfo aligninfo[128] = {
-	{ 4, LD },		/* 00 0 0000: lwz / lwarx */
-	INVALID,		/* 00 0 0001 */
-	{ 4, ST },		/* 00 0 0010: stw */
-	INVALID,		/* 00 0 0011 */
-	{ 2, LD },		/* 00 0 0100: lhz */
-	{ 2, LD+SE },		/* 00 0 0101: lha */
-	{ 2, ST },		/* 00 0 0110: sth */
-	{ 4, LD+M },		/* 00 0 0111: lmw */
-	{ 4, LD+F+S },		/* 00 0 1000: lfs */
-	{ 8, LD+F },		/* 00 0 1001: lfd */
-	{ 4, ST+F+S },		/* 00 0 1010: stfs */
-	{ 8, ST+F },		/* 00 0 1011: stfd */
-	INVALID,		/* 00 0 1100 */
-	INVALID,		/* 00 0 1101: ld/ldu/lwa */
-	INVALID,		/* 00 0 1110 */
-	INVALID,		/* 00 0 1111: std/stdu */
-	{ 4, LD+U },		/* 00 1 0000: lwzu */
-	INVALID,		/* 00 1 0001 */
-	{ 4, ST+U },		/* 00 1 0010: stwu */
-	INVALID,		/* 00 1 0011 */
-	{ 2, LD+U },		/* 00 1 0100: lhzu */
-	{ 2, LD+SE+U },		/* 00 1 0101: lhau */
-	{ 2, ST+U },		/* 00 1 0110: sthu */
-	{ 4, ST+M },		/* 00 1 0111: stmw */
-	{ 4, LD+F+S+U },	/* 00 1 1000: lfsu */
-	{ 8, LD+F+U },		/* 00 1 1001: lfdu */
-	{ 4, ST+F+S+U },	/* 00 1 1010: stfsu */
-	{ 8, ST+F+U },		/* 00 1 1011: stfdu */
-	INVALID,		/* 00 1 1100 */
-	INVALID,		/* 00 1 1101 */
-	INVALID,		/* 00 1 1110 */
-	INVALID,		/* 00 1 1111 */
-	INVALID,		/* 01 0 0000: ldx */
-	INVALID,		/* 01 0 0001 */
-	INVALID,		/* 01 0 0010: stdx */
-	INVALID,		/* 01 0 0011 */
-	INVALID,		/* 01 0 0100 */
-	INVALID,		/* 01 0 0101: lwax */
-	INVALID,		/* 01 0 0110 */
-	INVALID,		/* 01 0 0111 */
-	{ 4, LD+M+HARD+SX },	/* 01 0 1000: lswx */
-	{ 4, LD+M+HARD },	/* 01 0 1001: lswi */
-	{ 4, ST+M+HARD+SX },	/* 01 0 1010: stswx */
-	{ 4, ST+M+HARD },	/* 01 0 1011: stswi */
-	INVALID,		/* 01 0 1100 */
-	INVALID,		/* 01 0 1101 */
-	INVALID,		/* 01 0 1110 */
-	INVALID,		/* 01 0 1111 */
-	INVALID,		/* 01 1 0000: ldux */
-	INVALID,		/* 01 1 0001 */
-	INVALID,		/* 01 1 0010: stdux */
-	INVALID,		/* 01 1 0011 */
-	INVALID,		/* 01 1 0100 */
-	INVALID,		/* 01 1 0101: lwaux */
-	INVALID,		/* 01 1 0110 */
-	INVALID,		/* 01 1 0111 */
-	INVALID,		/* 01 1 1000 */
-	INVALID,		/* 01 1 1001 */
-	INVALID,		/* 01 1 1010 */
-	INVALID,		/* 01 1 1011 */
-	INVALID,		/* 01 1 1100 */
-	INVALID,		/* 01 1 1101 */
-	INVALID,		/* 01 1 1110 */
-	INVALID,		/* 01 1 1111 */
-	INVALID,		/* 10 0 0000 */
-	INVALID,		/* 10 0 0001 */
-	{ 0, ST+HARD },		/* 10 0 0010: stwcx. */
-	INVALID,		/* 10 0 0011 */
-	INVALID,		/* 10 0 0100 */
-	INVALID,		/* 10 0 0101 */
-	INVALID,		/* 10 0 0110 */
-	INVALID,		/* 10 0 0111 */
-	{ 4, LD+S },		/* 10 0 1000: lwbrx */
-	INVALID,		/* 10 0 1001 */
-	{ 4, ST+S },		/* 10 0 1010: stwbrx */
-	INVALID,		/* 10 0 1011 */
-	{ 2, LD+S },		/* 10 0 1100: lhbrx */
-	INVALID,		/* 10 0 1101 */
-	{ 2, ST+S },		/* 10 0 1110: sthbrx */
-	INVALID,		/* 10 0 1111 */
-	INVALID,		/* 10 1 0000 */
-	INVALID,		/* 10 1 0001 */
-	INVALID,		/* 10 1 0010 */
-	INVALID,		/* 10 1 0011 */
-	INVALID,		/* 10 1 0100 */
-	INVALID,		/* 10 1 0101 */
-	INVALID,		/* 10 1 0110 */
-	INVALID,		/* 10 1 0111 */
-	INVALID,		/* 10 1 1000 */
-	INVALID,		/* 10 1 1001 */
-	INVALID,		/* 10 1 1010 */
-	INVALID,		/* 10 1 1011 */
-	INVALID,		/* 10 1 1100 */
-	INVALID,		/* 10 1 1101 */
-	INVALID,		/* 10 1 1110 */
-	{ 0, ST+HARD },		/* 10 1 1111: dcbz */
-	{ 4, LD },		/* 11 0 0000: lwzx */
-	INVALID,		/* 11 0 0001 */
-	{ 4, ST },		/* 11 0 0010: stwx */
-	INVALID,		/* 11 0 0011 */
-	{ 2, LD },		/* 11 0 0100: lhzx */
-	{ 2, LD+SE },		/* 11 0 0101: lhax */
-	{ 2, ST },		/* 11 0 0110: sthx */
-	INVALID,		/* 11 0 0111 */
-	{ 4, LD+F+S },		/* 11 0 1000: lfsx */
-	{ 8, LD+F },		/* 11 0 1001: lfdx */
-	{ 4, ST+F+S },		/* 11 0 1010: stfsx */
-	{ 8, ST+F },		/* 11 0 1011: stfdx */
-	INVALID,		/* 11 0 1100 */
-	INVALID,		/* 11 0 1101: lmd */
-	INVALID,		/* 11 0 1110 */
-	INVALID,		/* 11 0 1111: stmd */
-	{ 4, LD+U },		/* 11 1 0000: lwzux */
-	INVALID,		/* 11 1 0001 */
-	{ 4, ST+U },		/* 11 1 0010: stwux */
-	INVALID,		/* 11 1 0011 */
-	{ 2, LD+U },		/* 11 1 0100: lhzux */
-	{ 2, LD+SE+U },		/* 11 1 0101: lhaux */
-	{ 2, ST+U },		/* 11 1 0110: sthux */
-	INVALID,		/* 11 1 0111 */
-	{ 4, LD+F+S+U },	/* 11 1 1000: lfsux */
-	{ 8, LD+F+U },		/* 11 1 1001: lfdux */
-	{ 4, ST+F+S+U },	/* 11 1 1010: stfsux */
-	{ 8, ST+F+U },		/* 11 1 1011: stfdux */
-	INVALID,		/* 11 1 1100 */
-	INVALID,		/* 11 1 1101 */
-	INVALID,		/* 11 1 1110 */
-	INVALID,		/* 11 1 1111 */
-};
-
-#define SWAP(a, b)	(t = (a), (a) = (b), (b) = t)
-
-int
-fix_alignment(struct pt_regs *regs)
-{
-	int instr, nb, flags;
-#if defined(CONFIG_4xx) || defined(CONFIG_POWER4) || defined(CONFIG_BOOKE)
-	int opcode, f1, f2, f3;
-#endif
-	int i, t;
-	int reg, areg;
-	int offset, nb0;
-	unsigned char __user *addr;
-	unsigned char *rptr;
-	union {
-		long l;
-		float f;
-		double d;
-		unsigned char v[8];
-	} data;
-
-	CHECK_FULL_REGS(regs);
-
-#if defined(CONFIG_4xx) || defined(CONFIG_POWER4) || defined(CONFIG_BOOKE)
-	/* The 4xx-family & Book-E processors have no DSISR register,
-	 * so we emulate it.
-	 * The POWER4 has a DSISR register but doesn't set it on
-	 * an alignment fault.  -- paulus
-	 */
-
-	if (__get_user(instr, (unsigned int __user *) regs->nip))
-		return 0;
-	opcode = OPCD(instr);
-	reg = RS(instr);
-	areg = RA(instr);
-
-	if (!IS_XFORM(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) {
-		long __user *p;
-		int i;
-
-		if (instr != DCBZ)
-			return 0;	/* too hard or invalid instruction */
-		/*
-		 * The dcbz (data cache block zero) instruction
-		 * gives an alignment fault if used on non-cacheable
-		 * memory.  We handle the fault mainly for the
-		 * case when we are running with the cache disabled
-		 * for debugging.
-		 */
-		p = (long __user *) (regs->dar & -L1_CACHE_BYTES);
-		if (user_mode(regs)
-		    && !access_ok(VERIFY_WRITE, p, L1_CACHE_BYTES))
-			return -EFAULT;
-		for (i = 0; i < L1_CACHE_BYTES / sizeof(long); ++i)
-			if (__put_user(0, p+i))
-				return -EFAULT;
-		return 1;
-	}
-
-	flags = aligninfo[instr].flags;
-	if ((flags & (LD|ST)) == 0)
-		return 0;
-
-	/* For the 4xx-family & Book-E processors, the 'dar' field of the
-	 * pt_regs structure is overloaded and is really from the DEAR.
-	 */
-
-	addr = (unsigned char __user *)regs->dar;
-
-	if (flags & M) {
-		/* lmw, stmw, lswi/x, stswi/x */
-		nb0 = 0;
-		if (flags & HARD) {
-			if (flags & SX) {
-				nb = regs->xer & 127;
-				if (nb == 0)
-					return 1;
-			} else {
-				if (__get_user(instr,
-					    (unsigned int __user *)regs->nip))
-					return 0;
-				nb = (instr >> 11) & 0x1f;
-				if (nb == 0)
-					nb = 32;
-			}
-			if (nb + reg * 4 > 128) {
-				nb0 = nb + reg * 4 - 128;
-				nb = 128 - reg * 4;
-			}
-		} else {
-			/* lwm, stmw */
-			nb = (32 - reg) * 4;
-		}
-
-		if (!access_ok((flags & ST? VERIFY_WRITE: VERIFY_READ), addr, nb+nb0))
-			return -EFAULT;	/* bad address */
-
-		rptr = (unsigned char *) &regs->gpr[reg];
-		if (flags & LD) {
-			for (i = 0; i < nb; ++i)
-				if (__get_user(rptr[i], addr+i))
-					return -EFAULT;
-			if (nb0 > 0) {
-				rptr = (unsigned char *) &regs->gpr[0];
-				addr += nb;
-				for (i = 0; i < nb0; ++i)
-					if (__get_user(rptr[i], addr+i))
-						return -EFAULT;
-			}
-			for (; (i & 3) != 0; ++i)
-				rptr[i] = 0;
-		} else {
-			for (i = 0; i < nb; ++i)
-				if (__put_user(rptr[i], addr+i))
-					return -EFAULT;
-			if (nb0 > 0) {
-				rptr = (unsigned char *) &regs->gpr[0];
-				addr += nb;
-				for (i = 0; i < nb0; ++i)
-					if (__put_user(rptr[i], addr+i))
-						return -EFAULT;
-			}
-		}
-		return 1;
-	}
-
-	offset = 0;
-	if (nb < 4) {
-		/* read/write the least significant bits */
-		data.l = 0;
-		offset = 4 - nb;
-	}
-
-	/* Verify the address of the operand */
-	if (user_mode(regs)) {
-		if (!access_ok((flags & ST? VERIFY_WRITE: VERIFY_READ), addr, nb))
-			return -EFAULT;	/* bad address */
-	}
-
-	if (flags & F) {
-		preempt_disable();
-		if (regs->msr & MSR_FP)
-			giveup_fpu(current);
-		preempt_enable();
-	}
-
-	/* If we read the operand, copy it in, else get register values */
-	if (flags & LD) {
-		for (i = 0; i < nb; ++i)
-			if (__get_user(data.v[offset+i], addr+i))
-				return -EFAULT;
-	} else if (flags & F) {
-		data.d = current->thread.fpr[reg];
-	} else {
-		data.l = regs->gpr[reg];
-	}
-
-	switch (flags & ~U) {
-	case LD+SE:	/* sign extend */
-		if (data.v[2] >= 0x80)
-			data.v[0] = data.v[1] = -1;
-		break;
-
-	case LD+S:	/* byte-swap */
-	case ST+S:
-		if (nb == 2) {
-			SWAP(data.v[2], data.v[3]);
-		} else {
-			SWAP(data.v[0], data.v[3]);
-			SWAP(data.v[1], data.v[2]);
-		}
-		break;
-
-	/* Single-precision FP load and store require conversions... */
-	case LD+F+S:
-#ifdef CONFIG_PPC_FPU
-		preempt_disable();
-		enable_kernel_fp();
-		cvt_fd(&data.f, &data.d, &current->thread);
-		preempt_enable();
-#else
-		return 0;
-#endif
-		break;
-	case ST+F+S:
-#ifdef CONFIG_PPC_FPU
-		preempt_disable();
-		enable_kernel_fp();
-		cvt_df(&data.d, &data.f, &current->thread);
-		preempt_enable();
-#else
-		return 0;
-#endif
-		break;
-	}
-
-	if (flags & ST) {
-		for (i = 0; i < nb; ++i)
-			if (__put_user(data.v[offset+i], addr+i))
-				return -EFAULT;
-	} else if (flags & F) {
-		current->thread.fpr[reg] = data.d;
-	} else {
-		regs->gpr[reg] = data.l;
-	}
-
-	if (flags & U)
-		regs->gpr[areg] = regs->dar;
-
-	return 1;
-}