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-rw-r--r--arch/hexagon/include/asm/bitops.h284
1 files changed, 284 insertions, 0 deletions
diff --git a/arch/hexagon/include/asm/bitops.h b/arch/hexagon/include/asm/bitops.h
new file mode 100644
index 000000000..71429f756
--- /dev/null
+++ b/arch/hexagon/include/asm/bitops.h
@@ -0,0 +1,284 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Bit operations for the Hexagon architecture
+ *
+ * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef _ASM_BITOPS_H
+#define _ASM_BITOPS_H
+
+#include <linux/compiler.h>
+#include <asm/byteorder.h>
+#include <asm/atomic.h>
+#include <asm/barrier.h>
+
+#ifdef __KERNEL__
+
+/*
+ * 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 int fls(unsigned 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 int 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