A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-29 11:11:45 -04:00
Code Issues Projects Releases Packages Wiki Activity

[PATCH] LOG2: Implement a general integer log2 facility in the kernel

Browse source 
This facility provides three entry points:

	ilog2()		Log base 2 of unsigned long
	ilog2_u32()	Log base 2 of u32
	ilog2_u64()	Log base 2 of u64

These facilities can either be used inside functions on dynamic data:

	int do_something(long q)
	{
		...;
		y = ilog2(x)
		...;
	}

Or can be used to statically initialise global variables with constant values:

	unsigned n = ilog2(27);

When performing static initialisation, the compiler will report "error:
initializer element is not constant" if asked to take a log of zero or of
something not reducible to a constant.  They treat negative numbers as
unsigned.

When not dealing with a constant, they fall back to using fls() which permits
them to use arch-specific log calculation instructions - such as BSR on
x86/x86_64 or SCAN on FRV - if available.

[[email protected]: MMC fix]
Signed-off-by: David Howells <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: David Howells <[email protected]>
Cc: Wojtek Kaniewski <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
David Howells 2006-12-08 02:37:49 -08:00 • committed by Linus Torvalds
commit f0d1b0b30d
36 changed files with 384 additions and 28 deletions
Download patch file Download diff file Expand all files Collapse all files

2
drivers/mmc/tifm_sd.c
View file

@ -387,7 +387,7 @@ static void tifm_sd_prepare_data(struct tifm_sd *card, struct mmc_command *cmd)
writel(TIFM_FIFO_INT_SETALL,
sock->addr + SOCK_DMA_FIFO_INT_ENABLE_CLEAR);
writel(long_log2(cmd->data->blksz) - 2,
writel(ilog2(cmd->data->blksz) - 2,
sock->addr + SOCK_FIFO_PAGE_SIZE);
writel(TIFM_FIFO_ENABLE, sock->addr + SOCK_FIFO_CONTROL);
writel(TIFM_FIFO_INTMASK, sock->addr + SOCK_DMA_FIFO_INT_ENABLE_SET);