lib: fix compilation when strings.h is included

In a systems that provide strings.h and it is included
together with sbi_bitops.h the compilation error appears.
The ffs() and fls() are provided by strings.h

Signed-off-by: Petro Karashchenko <petro.karashchenko@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

include/sbi/sbi_bitops.h

@@ -37,47 +37,12 @@
 	(((~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.
+ * sbi_ffs - find first (less-significant) set bit in a long 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)
+static inline int sbi_ffs(unsigned long word)
 {
 	int num = 0;
 
@@ -109,55 +74,20 @@ static inline int __ffs(unsigned long word)
 }
 
 /*
- * ffz - find first zero in word.
+ * sbi_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))
+#define sbi_ffz(x) sbi_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
+ * sbi_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)
+static inline unsigned long sbi_fls(unsigned long word)
 {
 	int num = BITS_PER_LONG - 1;
 

lib/sbi/sbi_bitops.c

@@ -39,7 +39,7 @@ unsigned long find_first_bit(const unsigned long *addr,
 	if (tmp == 0UL)		/* Are any bits set? */
 		return result + size;	/* Nope. */
 found:
-	return result + __ffs(tmp);
+	return result + sbi_ffs(tmp);
 }
 
 /**
@@ -69,7 +69,7 @@ unsigned long find_first_zero_bit(const unsigned long *addr,
 	if (tmp == ~0UL)	/* Are any bits zero? */
 		return result + size;	/* Nope. */
 found:
-	return result + ffz(tmp);
+	return result + sbi_ffz(tmp);
 }
 
 /**
@@ -100,7 +100,7 @@ unsigned long find_last_bit(const unsigned long *addr,
 		tmp = addr[--words];
 		if (tmp) {
 found:
-			return words * BITS_PER_LONG + __fls(tmp);
+			return words * BITS_PER_LONG + sbi_fls(tmp);
 		}
 	}
 
@@ -150,7 +150,7 @@ found_first:
 	if (tmp == 0UL)		/* Are any bits set? */
 		return result + size;	/* Nope. */
 found_middle:
-	return result + __ffs(tmp);
+	return result + sbi_ffs(tmp);
 }
 
 /**
@@ -196,5 +196,5 @@ found_first:
 	if (tmp == ~0UL)	/* Are any bits zero? */
 		return result + size;	/* Nope. */
 found_middle:
-	return result + ffz(tmp);
+	return result + sbi_ffz(tmp);
 }

lib/sbi/sbi_hart.c

@@ -386,7 +386,7 @@ static int hart_pmu_get_allowed_bits(void)
 		if (trap.cause)
 			return 0;
 	}
-	num_bits = __fls(val) + 1;
+	num_bits = sbi_fls(val) + 1;
 #if __riscv_xlen == 32
 	csr_write_allowed(CSR_MHPMCOUNTER3H, (ulong)&trap, val);
 	if (!trap.cause) {
@@ -394,7 +394,7 @@ static int hart_pmu_get_allowed_bits(void)
 		if (trap.cause)
 			return num_bits;
 	}
-	num_bits += __fls(val) + 1;
+	num_bits += sbi_fls(val) + 1;
 
 #endif
 
@@ -457,8 +457,8 @@ static void hart_detect_features(struct sbi_scratch *scratch)
 	 */
 	val = hart_pmp_get_allowed_addr();
 	if (val) {
-		hfeatures->pmp_gran =  1 << (__ffs(val) + 2);
-		hfeatures->pmp_addr_bits = __fls(val) + 1;
+		hfeatures->pmp_gran =  1 << (sbi_ffs(val) + 2);
+		hfeatures->pmp_addr_bits = sbi_fls(val) + 1;
 		/* Detect number of PMP regions. At least PMPADDR0 should be implemented*/
 		__check_csr_64(CSR_PMPADDR0, 0, val, pmp_count, __pmp_skip);
 	}

lib/sbi/sbi_pmu.c

@@ -347,7 +347,7 @@ int sbi_pmu_ctr_start(unsigned long cbase, unsigned long cmask,
 	int ret = SBI_EINVAL;
 	bool bUpdate = FALSE;
 
-	if (__fls(ctr_mask) >= total_ctrs)
+	if (sbi_fls(ctr_mask) >= total_ctrs)
 		return ret;
 
 	if (flags & SBI_PMU_START_FLAG_SET_INIT_VALUE)
@@ -421,7 +421,7 @@ int sbi_pmu_ctr_stop(unsigned long cbase, unsigned long cmask,
 	uint32_t event_code;
 	unsigned long ctr_mask = cmask << cbase;
 
-	if (__fls(ctr_mask) >= total_ctrs)
+	if (sbi_fls(ctr_mask) >= total_ctrs)
 		return SBI_EINVAL;
 
 	for_each_set_bit_from(cbase, &ctr_mask, total_ctrs) {
@@ -614,7 +614,7 @@ int sbi_pmu_ctr_cfg_match(unsigned long cidx_base, unsigned long cidx_mask,
 	unsigned long tmp = cidx_mask << cidx_base;
 
 	/* Do a basic sanity check of counter base & mask */
-	if (__fls(tmp) >= total_ctrs || event_type >= SBI_PMU_EVENT_TYPE_MAX)
+	if (sbi_fls(tmp) >= total_ctrs || event_type >= SBI_PMU_EVENT_TYPE_MAX)
 		return SBI_EINVAL;
 
 	if (flags & SBI_PMU_CFG_FLAG_SKIP_MATCH) {

lib/utils/timer/aclint_mtimer.c

@@ -154,7 +154,7 @@ static int aclint_mtimer_add_regions(unsigned long addr, unsigned long size)
 	while (pos < end) {
 		rsize = pos & (MTIMER_ADD_REGION_ALIGN - 1);
 		if (rsize)
-			rsize = 1UL << __ffs(pos);
+			rsize = 1UL << sbi_ffs(pos);
 		else
 			rsize = ((end - pos) < MTIMER_ADD_REGION_ALIGN) ?
 				(end - pos) : MTIMER_ADD_REGION_ALIGN;