Change in coreboot[master]: helpers: Add fls support

[Jianjun Wang (Code Review)]

Jianjun Wang has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/59738 )

Change subject: helpers: Add fls support
......................................................................

helpers: Add fls support

Introduce the C-language equivalent function of fls: find last
(most-significant) bit set.

Since x86 has its specific function, only used in non-x86 platform, and
remove the duplicate definitions in commonlib/storage/sdhci.c.

This code is copied from Linux kernel in: include/asm-generic/bitops/fls.h

Signed-off-by: Jianjun Wang 
Change-Id: Ib458abfec7e03b2979569a8440a6e69b0285ac32
---
M src/commonlib/bsd/include/commonlib/bsd/helpers.h
M src/commonlib/storage/sdhci.c
2 files changed, 38 insertions(+), 30 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/38/59738/1

diff --git a/src/commonlib/bsd/include/commonlib/bsd/helpers.h b/src/commonlib/bsd/include/commonlib/bsd/helpers.h
index 733b05a..80a1790 100644
--- a/src/commonlib/bsd/include/commonlib/bsd/helpers.h
+++ b/src/commonlib/bsd/include/commonlib/bsd/helpers.h
@@ -126,4 +126,42 @@
 #define retry(attempts, condition, ...) \
    _retry_impl(attempts, condition, __VA_ARGS__)

+#ifndef ARCH_X86
+/**
+ * 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 __always_inline int fls(unsigned 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)) {
+		x <<= 1;
+		r -= 1;
+	}
+	return r;
+}
+#endif
+
 #endif /* COMMONLIB_BSD_HELPERS_H */
diff --git a/src/commonlib/storage/sdhci.c b/src/commonlib/storage/sdhci.c
index 6d39a45..0dcc66e 100644
--- a/src/commonlib/storage/sdhci.c
+++ b/src/commonlib/storage/sdhci.c
@@ -411,36 +411,6 @@
    return 0;
 }

-/* Find leftmost set bit in a 32 bit integer */
-static int fls(u32 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)) {
-		x <<= 1;
-		r -= 1;
-	}
-	return r;
-}
-
 static void sdhci_set_power(struct sdhci_ctrlr *sdhci_ctrlr,
    unsigned short power)
 {