2021-03-05 23:55:08

by Michael Walle

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Subject: [PATCH] mtd: spi-nor: use is_power_of_2()

There is already a function to check if an integer is a power of 2. Use
it.

Signed-off-by: Michael Walle <[email protected]>
---
drivers/mtd/spi-nor/core.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 0522304f52fa..4a315cb1c4db 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -2336,11 +2336,8 @@ 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 {
uint64_t aux = addr;
--
2.20.1


2021-03-08 08:46:01

by Tudor Ambarus

[permalink] [raw]
Subject: Re: [PATCH] mtd: spi-nor: use is_power_of_2()

On Sat, 6 Mar 2021 00:45:52 +0100, Michael Walle wrote:
> There is already a function to check if an integer is a power of 2. Use
> it.

Applied to spi-nor/next, thanks!

[1/1] mtd: spi-nor: use is_power_of_2()
https://git.kernel.org/mtd/c/04fc298c7d08

Best regards,
--
Tudor Ambarus <[email protected]>

2021-03-08 09:03:28

by Pratyush Yadav

[permalink] [raw]
Subject: Re: [PATCH] mtd: spi-nor: use is_power_of_2()

On 06/03/21 12:45AM, Michael Walle wrote:
> There is already a function to check if an integer is a power of 2. Use
> it.
>
> Signed-off-by: Michael Walle <[email protected]>
> ---
> drivers/mtd/spi-nor/core.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> index 0522304f52fa..4a315cb1c4db 100644
> --- a/drivers/mtd/spi-nor/core.c
> +++ b/drivers/mtd/spi-nor/core.c
> @@ -2336,11 +2336,8 @@ 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 {
> uint64_t aux = addr;

Reviewed-by: Pratyush Yadav <[email protected]>

--
Regards,
Pratyush Yadav
Texas Instruments Inc.