Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

Pull powerpc updates from Benjamin Herrenschmidt:
 "The bulk of this is LE updates.  One should now be able to build an LE
  kernel and even run some things in it.

  I'm still sitting on a handful of patches to enable the new ABI that I
  *might* still send this merge window around, but due to the
  incertainty (they are pretty fresh) I want to keep them separate.

  Other notable changes are some infrastructure bits to better handle
  PCI pass-through under KVM, some bits and pieces added to the new
  PowerNV platform support such as access to the CPU SCOM bus via sysfs,
  and support for EEH error handling on PHB3 (Power8 PCIe).

  We also grew arch_get_random_long() for both pseries and powernv when
  running on P7+ and P8, exploiting the HW rng.

  And finally various embedded updates from freescale"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (154 commits)
  powerpc: Fix fatal SLB miss when restoring PPR
  powerpc/powernv: Reserve the correct PE number
  powerpc/powernv: Add PE to its own PELTV
  powerpc/powernv: Add support for indirect XSCOM via debugfs
  powerpc/scom: Improve debugfs interface
  powerpc/scom: Enable 64-bit addresses
  powerpc/boot: Properly handle the base "of" boot wrapper
  powerpc/bpf: Support MOD operation
  powerpc/bpf: Fix DIVWU instruction opcode
  of: Move definition of of_find_next_cache_node into common code.
  powerpc: Remove big endianness assumption in of_find_next_cache_node
  powerpc/tm: Remove interrupt disable in __switch_to()
  powerpc: word-at-a-time optimization for 64-bit Little Endian
  powerpc/bpf: BPF JIT compiler for 64-bit Little Endian
  powerpc: Only save/restore SDR1 if in hypervisor mode
  powerpc/pmu: Fix ADB_PMU_LED_IDE dependencies
  powerpc/nvram: Fix endian issue when using the partition length
  powerpc/nvram: Fix endian issue when reading the NVRAM size
  powerpc/nvram: Scan partitions only once
  powerpc/mpc512x: remove unnecessary #if
  ...

1 files changed, 85 insertions, 12 deletions

diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index b1faa1593c90..c0511c27a733 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -212,11 +212,19 @@ static int __kprobes read_mem_unaligned(unsigned long *dest, unsigned long ea,
 {
 	int err;
 	unsigned long x, b, c;
+#ifdef __LITTLE_ENDIAN__
+	int len = nb; /* save a copy of the length for byte reversal */
+#endif
 
 	/* unaligned, do this in pieces */
 	x = 0;
 	for (; nb > 0; nb -= c) {
+#ifdef __LITTLE_ENDIAN__
+		c = 1;
+#endif
+#ifdef __BIG_ENDIAN__
 		c = max_align(ea);
+#endif
 		if (c > nb)
 			c = max_align(nb);
 		err = read_mem_aligned(&b, ea, c);
@@ -225,7 +233,24 @@ static int __kprobes read_mem_unaligned(unsigned long *dest, unsigned long ea,
 		x = (x << (8 * c)) + b;
 		ea += c;
 	}
+#ifdef __LITTLE_ENDIAN__
+	switch (len) {
+	case 2:
+		*dest = byterev_2(x);
+		break;
+	case 4:
+		*dest = byterev_4(x);
+		break;
+#ifdef __powerpc64__
+	case 8:
+		*dest = byterev_8(x);
+		break;
+#endif
+	}
+#endif
+#ifdef __BIG_ENDIAN__
 	*dest = x;
+#endif
 	return 0;
 }
 
@@ -273,9 +298,29 @@ static int __kprobes write_mem_unaligned(unsigned long val, unsigned long ea,
 	int err;
 	unsigned long c;
 
+#ifdef __LITTLE_ENDIAN__
+	switch (nb) {
+	case 2:
+		val = byterev_2(val);
+		break;
+	case 4:
+		val = byterev_4(val);
+		break;
+#ifdef __powerpc64__
+	case 8:
+		val = byterev_8(val);
+		break;
+#endif
+	}
+#endif
 	/* unaligned or little-endian, do this in pieces */
 	for (; nb > 0; nb -= c) {
+#ifdef __LITTLE_ENDIAN__
+		c = 1;
+#endif
+#ifdef __BIG_ENDIAN__
 		c = max_align(ea);
+#endif
 		if (c > nb)
 			c = max_align(nb);
 		err = write_mem_aligned(val >> (nb - c) * 8, ea, c);
@@ -310,22 +355,36 @@ static int __kprobes do_fp_load(int rn, int (*func)(int, unsigned long),
 				struct pt_regs *regs)
 {
 	int err;
-	unsigned long val[sizeof(double) / sizeof(long)];
+	union {
+		double dbl;
+		unsigned long ul[2];
+		struct {
+#ifdef __BIG_ENDIAN__
+			unsigned _pad_;
+			unsigned word;
+#endif
+#ifdef __LITTLE_ENDIAN__
+			unsigned word;
+			unsigned _pad_;
+#endif
+		} single;
+	} data;
 	unsigned long ptr;
 
 	if (!address_ok(regs, ea, nb))
 		return -EFAULT;
 	if ((ea & 3) == 0)
 		return (*func)(rn, ea);
-	ptr = (unsigned long) &val[0];
+	ptr = (unsigned long) &data.ul;
 	if (sizeof(unsigned long) == 8 || nb == 4) {
-		err = read_mem_unaligned(&val[0], ea, nb, regs);
-		ptr += sizeof(unsigned long) - nb;
+		err = read_mem_unaligned(&data.ul[0], ea, nb, regs);
+		if (nb == 4)
+			ptr = (unsigned long)&(data.single.word);
 	} else {
 		/* reading a double on 32-bit */
-		err = read_mem_unaligned(&val[0], ea, 4, regs);
+		err = read_mem_unaligned(&data.ul[0], ea, 4, regs);
 		if (!err)
-			err = read_mem_unaligned(&val[1], ea + 4, 4, regs);
+			err = read_mem_unaligned(&data.ul[1], ea + 4, 4, regs);
 	}
 	if (err)
 		return err;
@@ -337,28 +396,42 @@ static int __kprobes do_fp_store(int rn, int (*func)(int, unsigned long),
 				 struct pt_regs *regs)
 {
 	int err;
-	unsigned long val[sizeof(double) / sizeof(long)];
+	union {
+		double dbl;
+		unsigned long ul[2];
+		struct {
+#ifdef __BIG_ENDIAN__
+			unsigned _pad_;
+			unsigned word;
+#endif
+#ifdef __LITTLE_ENDIAN__
+			unsigned word;
+			unsigned _pad_;
+#endif
+		} single;
+	} data;
 	unsigned long ptr;
 
 	if (!address_ok(regs, ea, nb))
 		return -EFAULT;
 	if ((ea & 3) == 0)
 		return (*func)(rn, ea);
-	ptr = (unsigned long) &val[0];
+	ptr = (unsigned long) &data.ul[0];
 	if (sizeof(unsigned long) == 8 || nb == 4) {
-		ptr += sizeof(unsigned long) - nb;
+		if (nb == 4)
+			ptr = (unsigned long)&(data.single.word);
 		err = (*func)(rn, ptr);
 		if (err)
 			return err;
-		err = write_mem_unaligned(val[0], ea, nb, regs);
+		err = write_mem_unaligned(data.ul[0], ea, nb, regs);
 	} else {
 		/* writing a double on 32-bit */
 		err = (*func)(rn, ptr);
 		if (err)
 			return err;
-		err = write_mem_unaligned(val[0], ea, 4, regs);
+		err = write_mem_unaligned(data.ul[0], ea, 4, regs);
 		if (!err)
-			err = write_mem_unaligned(val[1], ea + 4, 4, regs);
+			err = write_mem_unaligned(data.ul[1], ea + 4, 4, regs);
 	}
 	return err;
 }