Merge Qualcom Hexagon architecture

This is the fifth version of the patchset (with one tiny whitespace fix)
to the Linux kernel to support the Qualcomm Hexagon architecture.

Between now and the next pull requests, Richard Kuo should have his key
signed, etc., and should be back on kernel.org.  In the meantime, this
got merged as a emailed patch-series.

* Hexagon: (36 commits)
  Add extra arch overrides to asm-generic/checksum.h
  Hexagon: Add self to MAINTAINERS
  Hexagon: Add basic stacktrace functionality for Hexagon architecture.
  Hexagon: Add configuration and makefiles for the Hexagon architecture.
  Hexagon: Comet platform support
  Hexagon: kgdb support files
  Hexagon: Add page-fault support.
  Hexagon: Add page table header files & etc.
  Hexagon: Add ioremap support
  Hexagon: Provide DMA implementation
  Hexagon: Implement basic TLB management routines for Hexagon.
  Hexagon: Implement basic cache-flush support
  Hexagon: Provide basic implementation and/or stubs for I/O routines.
  Hexagon: Add user access functions
  Hexagon: Add locking types and functions
  Hexagon: Add SMP support
  Hexagon: Provide basic debugging and system trap support.
  Hexagon: Add ptrace support
  Hexagon: Add time and timer functions
  Hexagon: Add interrupts
  ...

1 files changed, 301 insertions, 0 deletions

diff --git a/arch/hexagon/include/asm/bitops.h b/arch/hexagon/include/asm/bitops.h
new file mode 100644
index 0000000..d23461e
--- /dev/null
+++ b/arch/hexagon/include/asm/bitops.h
@@ -0,0 +1,301 @@
+/*
+ * Bit operations for the Hexagon architecture
+ *
+ * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#ifndef _ASM_BITOPS_H
+#define _ASM_BITOPS_H
+
+#include <linux/compiler.h>
+#include <asm/byteorder.h>
+#include <asm/system.h>
+#include <asm/atomic.h>
+
+#ifdef __KERNEL__
+
+#define smp_mb__before_clear_bit()	barrier()
+#define smp_mb__after_clear_bit()	barrier()
+
+/*
+ * The offset calculations for these are based on BITS_PER_LONG == 32
+ * (i.e. I get to shift by #5-2 (32 bits per long, 4 bytes per access),
+ * mask by 0x0000001F)
+ *
+ * Typically, R10 is clobbered for address, R11 bit nr, and R12 is temp
+ */
+
+/**
+ * test_and_clear_bit - clear a bit and return its old value
+ * @nr:  bit number to clear
+ * @addr:  pointer to memory
+ */
+static inline int test_and_clear_bit(int nr, volatile void *addr)
+{
+	int oldval;
+
+	__asm__ __volatile__ (
+	"	{R10 = %1; R11 = asr(%2,#5); }\n"
+	"	{R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n"
+	"1:	R12 = memw_locked(R10);\n"
+	"	{ P0 = tstbit(R12,R11); R12 = clrbit(R12,R11); }\n"
+	"	memw_locked(R10,P1) = R12;\n"
+	"	{if !P1 jump 1b; %0 = mux(P0,#1,#0);}\n"
+	: "=&r" (oldval)
+	: "r" (addr), "r" (nr)
+	: "r10", "r11", "r12", "p0", "p1", "memory"
+	);
+
+	return oldval;
+}
+
+/**
+ * test_and_set_bit - set a bit and return its old value
+ * @nr:  bit number to set
+ * @addr:  pointer to memory
+ */
+static inline int test_and_set_bit(int nr, volatile void *addr)
+{
+	int oldval;
+
+	__asm__ __volatile__ (
+	"	{R10 = %1; R11 = asr(%2,#5); }\n"
+	"	{R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n"
+	"1:	R12 = memw_locked(R10);\n"
+	"	{ P0 = tstbit(R12,R11); R12 = setbit(R12,R11); }\n"
+	"	memw_locked(R10,P1) = R12;\n"
+	"	{if !P1 jump 1b; %0 = mux(P0,#1,#0);}\n"
+	: "=&r" (oldval)
+	: "r" (addr), "r" (nr)
+	: "r10", "r11", "r12", "p0", "p1", "memory"
+	);
+
+
+	return oldval;
+
+}
+
+/**
+ * test_and_change_bit - toggle a bit and return its old value
+ * @nr:  bit number to set
+ * @addr:  pointer to memory
+ */
+static inline int test_and_change_bit(int nr, volatile void *addr)
+{
+	int oldval;
+
+	__asm__ __volatile__ (
+	"	{R10 = %1; R11 = asr(%2,#5); }\n"
+	"	{R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n"
+	"1:	R12 = memw_locked(R10);\n"
+	"	{ P0 = tstbit(R12,R11); R12 = togglebit(R12,R11); }\n"
+	"	memw_locked(R10,P1) = R12;\n"
+	"	{if !P1 jump 1b; %0 = mux(P0,#1,#0);}\n"
+	: "=&r" (oldval)
+	: "r" (addr), "r" (nr)
+	: "r10", "r11", "r12", "p0", "p1", "memory"
+	);
+
+	return oldval;
+
+}
+
+/*
+ * Atomic, but doesn't care about the return value.
+ * Rewrite later to save a cycle or two.
+ */
+
+static inline void clear_bit(int nr, volatile void *addr)
+{
+	test_and_clear_bit(nr, addr);
+}
+
+static inline void set_bit(int nr, volatile void *addr)
+{
+	test_and_set_bit(nr, addr);
+}
+
+static inline void change_bit(int nr, volatile void *addr)
+{
+	test_and_change_bit(nr, addr);
+}
+
+
+/*
+ * These are allowed to be non-atomic.  In fact the generic flavors are
+ * in non-atomic.h.  Would it be better to use intrinsics for this?
+ *
+ * OK, writes in our architecture do not invalidate LL/SC, so this has to
+ * be atomic, particularly for things like slab_lock and slab_unlock.
+ *
+ */
+static inline void __clear_bit(int nr, volatile unsigned long *addr)
+{
+	test_and_clear_bit(nr, addr);
+}
+
+static inline void __set_bit(int nr, volatile unsigned long *addr)
+{
+	test_and_set_bit(nr, addr);
+}
+
+static inline void __change_bit(int nr, volatile unsigned long *addr)
+{
+	test_and_change_bit(nr, addr);
+}
+
+/*  Apparently, at least some of these are allowed to be non-atomic  */
+static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
+{
+	return test_and_clear_bit(nr, addr);
+}
+
+static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
+{
+	return test_and_set_bit(nr, addr);
+}
+
+static inline int __test_and_change_bit(int nr, volatile unsigned long *addr)
+{
+	return test_and_change_bit(nr, addr);
+}
+
+static inline int __test_bit(int nr, const volatile unsigned long *addr)
+{
+	int retval;
+
+	asm volatile(
+	"{P0 = tstbit(%1,%2); if (P0.new) %0 = #1; if (!P0.new) %0 = #0;}\n"
+	: "=&r" (retval)
+	: "r" (addr[BIT_WORD(nr)]), "r" (nr % BITS_PER_LONG)
+	: "p0"
+	);
+
+	return retval;
+}
+
+#define test_bit(nr, addr) __test_bit(nr, addr)
+
+/*
+ * ffz - find first zero in word.
+ * @word: The word to search
+ *
+ * Undefined if no zero exists, so code should check against ~0UL first.
+ */
+static inline long ffz(int x)
+{
+	int r;
+
+	asm("%0 = ct1(%1);\n"
+		: "=&r" (r)
+		: "r" (x));
+	return r;
+}
+
+/*
+ * fls - find last (most-significant) bit set
+ * @x: the word to search
+ *
+ * This is defined the same way as ffs.
+ * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
+ */
+static inline long fls(int x)
+{
+	int r;
+
+	asm("{ %0 = cl0(%1);}\n"
+		"%0 = sub(#32,%0);\n"
+		: "=&r" (r)
+		: "r" (x)
+		: "p0");
+
+	return r;
+}
+
+/*
+ * ffs - find first bit set
+ * @x: the word to search
+ *
+ * This is defined the same way as
+ * the libc and compiler builtin ffs routines, therefore
+ * differs in spirit from the above ffz (man ffs).
+ */
+static inline long ffs(int x)
+{
+	int r;
+
+	asm("{ P0 = cmp.eq(%1,#0); %0 = ct0(%1);}\n"
+		"{ if P0 %0 = #0; if !P0 %0 = add(%0,#1);}\n"
+		: "=&r" (r)
+		: "r" (x)
+		: "p0");
+
+	return r;
+}
+
+/*
+ * __ffs - find first bit in word.
+ * @word: The word to search
+ *
+ * Undefined if no bit exists, so code should check against 0 first.
+ *
+ * bits_per_long assumed to be 32
+ * numbering starts at 0 I think (instead of 1 like ffs)
+ */
+static inline unsigned long __ffs(unsigned long word)
+{
+	int num;
+
+	asm("%0 = ct0(%1);\n"
+		: "=&r" (num)
+		: "r" (word));
+
+	return num;
+}
+
+/*
+ * __fls - find last (most-significant) set bit in a long word
+ * @word: the word to search
+ *
+ * Undefined if no set bit exists, so code should check against 0 first.
+ * bits_per_long assumed to be 32
+ */
+static inline unsigned long __fls(unsigned long word)
+{
+	int num;
+
+	asm("%0 = cl0(%1);\n"
+		"%0 = sub(#31,%0);\n"
+		: "=&r" (num)
+		: "r" (word));
+
+	return num;
+}
+
+#include <asm-generic/bitops/lock.h>
+#include <asm-generic/bitops/find.h>
+
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/sched.h>
+#include <asm-generic/bitops/hweight.h>
+
+#include <asm-generic/bitops/le.h>
+#include <asm-generic/bitops/ext2-atomic.h>
+
+#endif /* __KERNEL__ */
+#endif