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>
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (76 commits)
[ARM] 4002/1: S3C24XX: leave parent IRQs unmasked
[ARM] 4001/1: S3C24XX: shorten reboot time
[ARM] 3983/2: remove unused argument to __bug()
[ARM] 4000/1: Osiris: add third serial port in
[ARM] 3999/1: RX3715: suspend to RAM support
[ARM] 3998/1: VR1000: LED platform devices
[ARM] 3995/1: iop13xx: add iop13xx support
[ARM] 3968/1: iop13xx: add iop13xx_defconfig
[ARM] Update mach-types
[ARM] Allow gcc to optimise arm_add_memory a little more
[ARM] 3991/1: i.MX/MX1 high resolution time source
[ARM] 3990/1: i.MX/MX1 more precise PLL decode
[ARM] 3986/1: H1940: suspend to RAM support
[ARM] 3985/1: ixp4xx clocksource cleanup
[ARM] 3984/1: ixp4xx/nslu2: Fix disk LED numbering (take 2)
[ARM] 3994/1: ixp23xx: fix handling of pci master aborts
[ARM] 3981/1: sched_clock for PXA2xx
[ARM] 3980/1: extend the ARM Versatile sched_clock implementation from 32 to 63 bit
[ARM] 3979/1: extend the SA11x0 sched_clock implementation from 32 to 63 bit period
[ARM] 3978/1: macro to provide a 63-bit value from a 32-bit hardware counter
...
Conflicts:
drivers/infiniband/core/iwcm.c
drivers/net/chelsio/cxgb2.c
drivers/net/wireless/bcm43xx/bcm43xx_main.c
drivers/net/wireless/prism54/islpci_eth.c
drivers/usb/core/hub.h
drivers/usb/input/hid-core.c
net/core/netpoll.c
Fix up merge failures with Linus's head and fix new compilation failures.
Signed-Off-By: David Howells <dhowells@redhat.com>
This patch has fixed the following build error abou au1xmmc.
drivers/mmc/au1xmmc.c: In function `au1xmmc_poll_event':
drivers/mmc/au1xmmc.c:835: warning: unused variable `status'
drivers/mmc/au1xmmc.c: At top level:
drivers/mmc/au1xmmc.c:878: error: parse error before "const"
drivers/mmc/au1xmmc.c: In function `au1xmmc_probe':
drivers/mmc/au1xmmc.c:909: error: `au1xmmc_ops' undeclared (first use in this function)
drivers/mmc/au1xmmc.c:909: error: (Each undeclared identifier is reported only once
drivers/mmc/au1xmmc.c:909: error: for each function it appears in.)
drivers/mmc/au1xmmc.c: At top level:
drivers/mmc/au1xmmc.c:659: warning: 'au1xmmc_request' defined but not used
drivers/mmc/au1xmmc.c:719: warning: 'au1xmmc_set_ios' defined but not used
make[2]: *** [drivers/mmc/au1xmmc.o] Error 1
make[1]: *** [drivers/mmc] Error 2
make: *** [drivers] Error 2
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
since commit fcaf71fd51
struct mmc_host does not have a dev field. Retrieve the device with
mmc_dev() instead.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/drzeus/mmc:
mmc: correct request error handling
mmc: Flush block queue when removing card
mmc: sdhci high speed support
mmc: Support for high speed SD cards
mmc: Fix mmc_delay() function
mmc: Add support for mmc v4 wide-bus modes
[PATCH] mmc: Add support for mmc v4 high speed mode
trivial change for mmc/Kconfig: MMC_PXA does not mean only PXA255
Make general code cleanups
Add MMC_CAP_{MULTIWRITE,BYTEBLOCK} flags
Platform device error handling cleanup
Move register definitions away from the header file
Change OMAP_MMC_{READ,WRITE} macros to use the host pointer
Replace base with virt_base and phys_base
mmc: constify mmc_host_ops vectors
mmc: remove kernel_thread()
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (36 commits)
Driver core: show drivers in /sys/module/
Documentation/driver-model/platform.txt update/rewrite
Driver core: platform_driver_probe(), can save codespace
driver core: Use klist_remove() in device_move()
driver core: Introduce device_move(): move a device to a new parent.
Driver core: make drivers/base/core.c:setup_parent() static
driver core: Introduce device_find_child().
sysfs: sysfs_write_file() writes zero terminated data
cpu topology: consider sysfs_create_group return value
Driver core: Call platform_notify_remove later
ACPI: Change ACPI to use dev_archdata instead of firmware_data
Driver core: add dev_archdata to struct device
Driver core: convert sound core to use struct device
Driver core: change mem class_devices to be real devices
Driver core: convert fb code to use struct device
Driver core: convert firmware code to use struct device
Driver core: convert mmc code to use struct device
Driver core: convert ppdev code to use struct device
Driver core: convert PPP code to use struct device
Driver core: convert cpuid code to use struct device
...
Converts from using struct "class_device" to "struct device" making
everything show up properly in /sys/devices/ with symlinks from the
/sys/class directory.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We need to jump to the part of just flushing the request
when we cannot claim the bus. Sending commands to a bus
we do not own will give unpredictable results.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
After mmc_block's remove function has exited, we must not
touch the card structure in any way. This means we not only
must remove the gendisk, we must also flush out any
remaning requests already queued up.
We previously removed the disk, but didn't flush it,
causing oops:es when removing a card in the middle of a
transfer.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The SDHCI spec implies that is is incorrect to set a clock
frequency above 25 MHz without setting the high speed bit.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Modern SD cards support a clock speed of 50 MHz. Make sure we test for
this capability and do the song and dance required to activate it.
Activating high speed support actually modifies the TRAN_SPEED field
of the CSD. But as the spec says that the cards must report 50 MHz,
we might as well skip re-reading the CSD.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Several fixes for mmc_delay():
* Repair if-clause that was supposed to detect sub-hz delays.
* Change yield() to cond_resched() as yield() no longer has the
semantics we desire.
* mmc_delay() is used to guarantee protocol delays, so we cannot
return early (i.e. use _interruptable).
Based on patch by Amol Lad.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This change adds support for the mmc4 4-bit wide-bus mode.
The mmc4 spec defines 8-bit and 4-bit transfer modes. As we do not support
any 8-bit hardware, this patch only adds support for the 4-bit mode, but
it can easily be built upon when the time comes.
The 4-bit mode is electrically compatible with SD's 4-bit mode but the
procedure for turning it on is different. This patch implements only
the essential parts of the procedure as defined by the spec. Two additional
steps are recommended but not compulsory. I am documenting them here so
that there's a record.
1) A bus-test mechanism is implemented using dedicated mmc commands which allow
for testing the functionality of the data bus at the electrical level. This is
pretty paranoid and they way the commands work is not compatible with the mmc
subsystem (they don't set valid CRC values).
2) MMC v4 cards can indicate they would like to draw more than the default
amount of current in wide-bus modes. We currently will never switch the card
into a higher draw mode. Supposedly, allowing the card to draw more current
will let it perform better, but the specs seem to indicate that the card will
function correctly without the mode change. Empirical testing supports this
interpretation.
Signed-off-by: Philip Langdale <philipl@overt.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This adds support for the high-speed modes defined by mmc v4
(assuming the host controller is up to it). On a TI sdhci controller,
it improves read speed from 1.3MBps to 2.3MBps. The TI controller can
only go up to 24MHz, but everything helps. Another person has taken
this basic patch and used it on a Nokia 770 to get a bigger boost
because that controller can run at 48MHZ.
Signed-off-by: Philip Langdale <philipl@overt.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
PXA MMC driver supports not only PXA255 but also PXA250 and newer ones
Signed-off-by: Marcin Juszkiewicz <hrw@openembedded.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch is part of Juha Yrjola's and Komal Shah's earlier patch to
make general code cleanups
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar <at> indt.org.br>
Signed-off-by: Juha Yrjola <juha.yrjola <at> solidboot.com>
Signed-off-by: Komal Shah <komal_shah802003 <at> yahoo.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch is part of Tony Lindgren's earlier patch to add
MMC_CAP_{MULTIWRITE,BYTEBLOCK} flags in omap.c
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar <at> indt.org.br>
Signed-off-by: Tony Lindgren <tony <at> atomide.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch is part of Juha Yrjola's earlier patch to add platform device
error handling and a BUG_ON to verify if host == NULL
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar <at> indt.org.br>
Signed-off-by: Juha Yrjola <juha.yrjola <at> solidboot.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch is part of Juha Yrjola's earlier patch to move register
definitions away from the header file and the header file is removed.
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar <at> indt.org.br>
Signed-off-by: Juha Yrjola <juha.yrjola <at> solidboot.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch is part of Juha Yrjola's earlier patch to change
OMAP_MMC_{READ,WRITE} macros to use the host pointer
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar <at> indt.org.br>
Signed-off-by: Juha Yrjola <juha.yrjola <at> solidboot.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch is part of Juha Yrjola's earlier patch to replace base
with virt_base and phys_base
Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar <at> indt.org.br>
Signed-off-by: Juha Yrjola <juha.yrjola <at> solidboot.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Now that mmc_host_ops can be constified, update the various drivers
to constify those method tables and shrink the writable data segment.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Replace kernel_thread() with kthread_run()/kthread_stop().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
