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-rw-r--r--roms/opensbi/include/sbi/sbi_bitops.h320
1 files changed, 320 insertions, 0 deletions
diff --git a/roms/opensbi/include/sbi/sbi_bitops.h b/roms/opensbi/include/sbi/sbi_bitops.h
new file mode 100644
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--- /dev/null
+++ b/roms/opensbi/include/sbi/sbi_bitops.h
@@ -0,0 +1,320 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ * Atish Patra <atish.patra@wdc.com>
+ */
+
+#ifndef __SBI_BITOPS_H__
+#define __SBI_BITOPS_H__
+
+#include <sbi/sbi_types.h>
+
+#if __SIZEOF_POINTER__ == 8
+#define BITS_PER_LONG 64
+#elif __SIZEOF_POINTER__ == 4
+#define BITS_PER_LONG 32
+#else
+#error "Unexpected __SIZEOF_POINTER__"
+#endif
+
+#define EXTRACT_FIELD(val, which) \
+ (((val) & (which)) / ((which) & ~((which)-1)))
+#define INSERT_FIELD(val, which, fieldval) \
+ (((val) & ~(which)) | ((fieldval) * ((which) & ~((which)-1))))
+
+#define BITS_TO_LONGS(nbits) (((nbits) + BITS_PER_LONG - 1) / \
+ BITS_PER_LONG)
+
+#define BIT(nr) (1UL << (nr))
+#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
+#define BIT_WORD(bit) ((bit) / BITS_PER_LONG)
+#define BIT_WORD_OFFSET(bit) ((bit) & (BITS_PER_LONG - 1))
+
+#define GENMASK(h, l) \
+ (((~0UL) - (1UL << (l)) + 1) & (~0UL >> (BITS_PER_LONG - 1 - (h))))
+
+/**
+ * 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 = 1;
+
+ if (!x)
+ return 0;
+ if (!(x & 0xffff)) {
+ x >>= 16;
+ r += 16;
+ }
+ if (!(x & 0xff)) {
+ x >>= 8;
+ r += 8;
+ }
+ if (!(x & 0xf)) {
+ x >>= 4;
+ r += 4;
+ }
+ if (!(x & 3)) {
+ x >>= 2;
+ r += 2;
+ }
+ if (!(x & 1))
+ r += 1;
+ 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.
+ */
+static inline int __ffs(unsigned long word)
+{
+ int num = 0;
+
+#if BITS_PER_LONG == 64
+ if ((word & 0xffffffff) == 0) {
+ num += 32;
+ word >>= 32;
+ }
+#endif
+ if ((word & 0xffff) == 0) {
+ num += 16;
+ word >>= 16;
+ }
+ if ((word & 0xff) == 0) {
+ num += 8;
+ word >>= 8;
+ }
+ if ((word & 0xf) == 0) {
+ num += 4;
+ word >>= 4;
+ }
+ if ((word & 0x3) == 0) {
+ num += 2;
+ word >>= 2;
+ }
+ if ((word & 0x1) == 0)
+ num += 1;
+ return num;
+}
+
+/*
+ * ffz - find first zero in word.
+ * @word: The word to search
+ *
+ * Undefined if no zero exists, so code should check against ~0UL first.
+ */
+#define ffz(x) __ffs(~(x))
+
+/**
+ * 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(int x)
+{
+ int r = 32;
+
+ if (!x)
+ return 0;
+ if (!(x & 0xffff0000u)) {
+ x <<= 16;
+ r -= 16;
+ }
+ if (!(x & 0xff000000u)) {
+ x <<= 8;
+ r -= 8;
+ }
+ if (!(x & 0xf0000000u)) {
+ x <<= 4;
+ r -= 4;
+ }
+ if (!(x & 0xc0000000u)) {
+ x <<= 2;
+ r -= 2;
+ }
+ if (!(x & 0x80000000u))
+ r -= 1;
+ return r;
+}
+
+/**
+ * __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.
+ */
+static inline unsigned long __fls(unsigned long word)
+{
+ int num = BITS_PER_LONG - 1;
+
+#if BITS_PER_LONG == 64
+ if (!(word & (~0ul << 32))) {
+ num -= 32;
+ word <<= 32;
+ }
+#endif
+ if (!(word & (~0ul << (BITS_PER_LONG-16)))) {
+ num -= 16;
+ word <<= 16;
+ }
+ if (!(word & (~0ul << (BITS_PER_LONG-8)))) {
+ num -= 8;
+ word <<= 8;
+ }
+ if (!(word & (~0ul << (BITS_PER_LONG-4)))) {
+ num -= 4;
+ word <<= 4;
+ }
+ if (!(word & (~0ul << (BITS_PER_LONG-2)))) {
+ num -= 2;
+ word <<= 2;
+ }
+ if (!(word & (~0ul << (BITS_PER_LONG-1))))
+ num -= 1;
+ return num;
+}
+
+#define for_each_set_bit(bit, addr, size) \
+ for ((bit) = find_first_bit((addr), (size)); \
+ (bit) < (size); \
+ (bit) = find_next_bit((addr), (size), (bit) + 1))
+
+/* same as for_each_set_bit() but use bit as value to start with */
+#define for_each_set_bit_from(bit, addr, size) \
+ for ((bit) = find_next_bit((addr), (size), (bit)); \
+ (bit) < (size); \
+ (bit) = find_next_bit((addr), (size), (bit) + 1))
+
+#define for_each_clear_bit(bit, addr, size) \
+ for ((bit) = find_first_zero_bit((addr), (size)); \
+ (bit) < (size); \
+ (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
+
+/* same as for_each_clear_bit() but use bit as value to start with */
+#define for_each_clear_bit_from(bit, addr, size) \
+ for ((bit) = find_next_zero_bit((addr), (size), (bit)); \
+ (bit) < (size); \
+ (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
+
+unsigned long find_first_bit(const unsigned long *addr,
+ unsigned long size);
+
+unsigned long find_first_zero_bit(const unsigned long *addr,
+ unsigned long size);
+
+unsigned long find_last_bit(const unsigned long *addr,
+ unsigned long size);
+
+unsigned long find_next_bit(const unsigned long *addr,
+ unsigned long size, unsigned long offset);
+
+unsigned long find_next_zero_bit(const unsigned long *addr,
+ unsigned long size,
+ unsigned long offset);
+
+/**
+ * __set_bit - Set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This function is non-atomic and may be reordered.
+ */
+static inline void __set_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+
+ *p |= mask;
+}
+
+/**
+ * __clear_bit - Clear a bit in memory
+ * @nr: the bit to clear
+ * @addr: the address to start counting from
+ *
+ * This function is non-atomic and may be reordered.
+ */
+static inline void __clear_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+
+ *p &= ~mask;
+}
+
+/**
+ * __change_bit - Toggle a bit in memory
+ * @nr: the bit to change
+ * @addr: the address to start counting from
+ *
+ * This function is non-atomic and may be reordered.
+ */
+static inline void __change_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+
+ *p ^= mask;
+}
+
+/**
+ * __test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ */
+static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ unsigned long old = *p;
+
+ *p = old | mask;
+ return (old & mask) != 0;
+}
+
+/**
+ * __test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ */
+static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ unsigned long old = *p;
+
+ *p = old & ~mask;
+ return (old & mask) != 0;
+}
+
+/**
+ * __test_bit - Determine whether a bit is set
+ * @nr: bit number to test
+ * @addr: Address to start counting from
+ *
+ * This operation is non-atomic and can be reordered.
+ */
+static inline int __test_bit(int nr, const volatile unsigned long *addr)
+{
+ return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
+}
+
+#endif