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.
[akpm@osdl.org: MMC fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Wojtek Kaniewski <wojtekka@toxygen.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following moves the creation of IPR interupts into setup-7750.c
and updates a few other things to make it all work after the "Drop
CPU subtype IRQ headers" commit. It boots and runs fine on my titan
board.
- adds an ipr_idx to the ipr_data and uses a function in the subtype
code to calculate the address of the IPR registers
- adds a function to enable individual interrupt mode for externals
in the subtype code and calls that from the titan board code
instead of doing it directly.
- I changed the shift in the ipr_data to be the actual # of bits to
shift, instead of the numnber / 4 - made it easier to match with
the manual.
Signed-off-by: Jamie Lenehan <lenehan@twibble.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds basic NO_IDLE_HZ support to the SH timer API so timers
are able to wire it up. Taken from the ARM version, as it fit in
to our API with very few changes needed.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Handle simple TLB miss faults which can be resolved completely
from the page table in assembler.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds support for a generic push switch framework. Adaptable for
various switches, including GPIO switches and the push switches commonly
found on Renesas debug boards.
This allows switch states to be trivially reported through sysfs.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Previously big endian was simply assumed if little endian was
not set, which led to some cflags ordering issues. There's not
much point to not having a big endian option, so shove one in
a choice and wire it up in the Makefile.
This lets us clean up some of the cflags ordering while we're
at it.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
All of the various CPU subtypes currently hardcode TIMER_IRQ,
switch this to a config option in the few places we need this.
This allows further removal of hardcoded IRQ headers..
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements initial support for the SH7206 (SH-2A) and SH7619
(SH-2) MMU-less CPUs.
Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
At the moment we wrap GENERIC_TIME around our existing timer API.
As boards start providing their own clocksources, they're able to
select GENERIC_TIME accordingly and optimize out most of the timer
API.
Once the current timers have been reworked as proper clocksource
drivers, the rest of the place holders for the timer API can go
away and we can flip on GENERIC_TIME unconditionally.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
None of these have been maintained in years, and no one seems to
be interested in doing so, so just get rid of them.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds support for the aforementioned CPU subtypes, and cleans
up some build issues encountered as a result.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
nommu needs to be able to shift PAGE_OFFSET, so we switch it to a
non-user-visible CONFIG_PAGE_OFFSET and use that in the few places
where it matters.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds some simple PM stubs and the basic APM interfaces,
primarily for use by hp6xx, where the existing userland
expects it.
Signed-off-by: Andriy Skulysh <askulysh@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>