diff options
| author | Rasmus Villemoes <rasmus.villemoes@prevas.dk> | 2020-03-13 01:06:38 +0100 |
|---|---|---|
| committer | Jagan Teki <jagan@amarulasolutions.com> | 2020-04-29 01:44:35 +0530 |
| commit | 7ddea756540b5adddfde3b890fa46a40c649e68f (patch) | |
| tree | 818c6604e5cb8757a1b7609b609d3d2f1af362be /drivers/mtd | |
| parent | 91afd36f3802aee001a2f551ea1d77aca428b0a9 (diff) | |
spi: use is_power_of_2 instead of hweight32 in spi_nor_write()
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.villemoes@prevas.dk>
Acked-by: Vignesh Raghavendra <vigneshr@ti.com>
Acked-by: Jagan Teki <jagan@amarulasolutions.com>
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/spi/spi-nor-core.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index 7b6ad495ac..3bf8ddfb9d 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -1246,11 +1246,8 @@ 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; |