hweight32 is a somewhat expensive way to check for power-of-2. Use the
is_power_of_2 helper, which does the standard and cheap idiom
foo&(foo-1)==0.
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-96 (-96)
Function old new delta
spi_nor_write 388 292 -96
Signed-off-by: Rasmus Villemoes <rasmus.villem...@prevas.dk>
---
drivers/mtd/spi/spi-nor-core.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
index eb49a6c11c..4076646225 100644
--- a/drivers/mtd/spi/spi-nor-core.c
+++ b/drivers/mtd/spi/spi-nor-core.c
@@ -1240,11 +1240,8 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t
to, size_t len,
* If page_size is a power of two, the offset can be quickly
* calculated with an AND operation. On the other cases we
* need to do a modulus operation (more expensive).
- * Power of two numbers have only one bit set and we can use
- * the instruction hweight32 to detect if we need to do a
- * modulus (do_div()) or not.
*/
- if (hweight32(nor->page_size) == 1) {
+ if (is_power_of_2(nor->page_size)) {
page_offset = addr & (nor->page_size - 1);
} else {
u64 aux = addr;
--
2.23.0
