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2006-03-28ppc: Remove CHRP, POWER3 and POWER4 support from arch/ppcPaul Mackerras
32-bit CHRP machines are now supported only in arch/powerpc, as are all 64-bit PowerPC processors. This means that we don't use Open Firmware on any platform in arch/ppc any more. This makes PReP support a single-platform option like every other platform support option in arch/ppc now, thus CONFIG_PPC_MULTIPLATFORM is gone from arch/ppc. CONFIG_PPC_PREP is the option that selects PReP support and is generally what has replaced CONFIG_PPC_MULTIPLATFORM within arch/ppc. _machine is all but dead now, being #defined to 0. Updated Makefiles, comments and Kconfig options generally to reflect these changes. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28powerpc: Fix goof in 6xx and POWER4 idle power-save functionsPaul Mackerras
This fixes a mistake I made when editing these functions - when I took out the interrupt disabling code (because interrupts are now disabled by the caller) I left the register that is used for the MSR value to be used during doze/nap uninitialized. This fixes it. Also updated some of the comments in idle_power4.S and removed some code that was copied over from idle_6xx.S but is no longer relevant (we don't ever clear the CPU_FTR_CAN_NAP bit at runtime for POWER4). Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Fix event-scan code for 32-bit CHRPPaul Mackerras
On CHRP machines we are supposed to call into firmware (RTAS) periodically, to give it a chance to check for errors and other events. Under ppc we had some special code in timer_interrupt to do this, but that didn't get transferred over to arch/powerpc. Instead, we use an array of timer_list structs, one per CPU, and use add_timer_on to make sure each one gets called on the appropriate CPU. With this we can remove the heartbeat_* elements of the ppc_md struct. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27ppc: Remove duplicate exports of __down, __up etc.Paul Mackerras
__down, __down_interruptible and __up are defined and exported in arch/powerpc/kernel/semaphore.c, and used from there for ARCH=ppc, so there is no need to export them in arch/ppc/kernel/ppc_ksyms.c. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Don't compile in arch/ppc/kernel for 32-bit ARCH=powerpcPaul Mackerras
All of the things needed for 32-bit ARCH=powerpc builds have now moved to arch/powerpc/kernel, so we don't need to go down into arch/ppc/kernel any more, and we can remove the CONFIG_PPC_MERGE conditional from arch/ppc/kernel/Makefile. There were two files still referenced in the merge section of arch/ppc/kernel/Makefile: ppc-stub.o, depending on CONFIG_KGDB, and dma-mapping.o, depending on CONFIG_NOT_COHERENT_CACHE. None of the platforms currently in ARCH=powerpc have caches that aren't coherent with DMA, but when we do get one we'll move dma-mapping.c over. As for CONFIG_KGDB, none of the Kconfig files in the tree define it, so I'll let it languish for now. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Move perfmon_fsl_booke.c over to arch/powerpcPaul Mackerras
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Move module.c over to arch/powerpcPaul Mackerras
... and rename it to module_32.c since it is the 32-bit version. The 32-bit and 64-bit ABIs are sufficiently different that having a merged version isn't really practical. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Move swsusp.S over to arch/powerpcPaul Mackerras
... and rename it to swsusp_32.S, since it's 32-bit only at this stage. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Move cpu_setup_6xx.S and temp.c over to arch/powerpcPaul Mackerras
Also renamed temp.c to tau_6xx.c (for thermal assist unit) and updated the Kconfig option description and help text for CONFIG_TAU. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Move l2cr.S over to arch/powerpcPaul Mackerras
No functional changes, but call it l2cr_6xx.S since it is specific to 6xx-family (including G3/750 and G4/74xx) processors. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Simplify pSeries idle loopPaul Mackerras
Since pSeries only wants to do something different in the idle loop when there is no work to do, we can simplify the code by implementing ppc_md.power_save functions instead of complete idle loops. There are two versions: one for shared-processor partitions and one for dedicated- processor partitions. With this we also do a cede_processor() call on dedicated processor partitions if the poll_pending() call indicates that the hypervisor has work it wants to do. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27powerpc: Unify the 32 and 64 bit idle loopsPaul Mackerras
This unifies the 32-bit (ARCH=ppc and ARCH=powerpc) and 64-bit idle loops. It brings over the concept of having a ppc_md.power_save function from 32-bit to ARCH=powerpc, which lets us get rid of native_idle(). With this we will also be able to simplify the idle handling for pSeries and cell. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: HVC init raceMichael Neuling
I've been hitting a crash on boot where tty_open is being called before the hvc console driver setup is complete. This fixes the problem. Thanks to benh for his help on this. Signed-off-by: Michael Neuling <mikey@neuling.org> Acked-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] ppc32: Reorganize and complete MPC52xx initial cpu setupSylvain Munaut
ppc32: Reorganize and complete MPC52xx initial cpu setup This patch splits up the CPU setup into a generic part and a platform specific part. We also add a few missing init at the same time. Signed-off-by: Sylvain Munaut <tnt@246tNt.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] ppc32: Adds support for the LITE5200B dev boardSylvain Munaut
ppc32: Adds support for the LITE5200B dev board This LITE5200B devboard is the new development board for the Freescale MPC5200 processor. It has two PCI slots and so a different PCI IRQ routing. Signed-off-by: John Rigby <jrigby@freescale.com> Signed-off-by: Sylvain Munaut <tnt@246tNt.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] ppc32: Adds support for the PCI hostbridge in MPC5200BSylvain Munaut
ppc32: Adds support for the PCI hostbridge in MPC5200B Signed-off-by: John Rigby <jrigby@freescale.com> Signed-off-by: Sylvain Munaut <tnt@246tNt.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: legacy_serial loop cleanupMichael Neuling
We only ever execute the loop once, so let's move it to a function making it more readable. Cleanup patch, no functional change. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: Compile warning in hvcs driverAnton Blanchard
We ended up with an unused variable after the tty updates went in. Fix it. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: Consistent printing of node idAnton Blanchard
We were printing node ids in hex in one spot. Lets be consistent and always print them in decimal. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: Allow non zero boot cpuidsAnton Blanchard
We currently have a hack to flip the boot cpu and its secondary thread to logical cpuid 0 and 1. This means the logical - physical mapping will differ depending on which cpu is boot cpu. This is most apparent on kexec, where we might kexec on any cpu and therefore change the mapping from boot to boot. The patch below does a first pass early on to work out the logical cpuid of the boot thread. We then fix up some paca structures to match. Ive also removed the boot_cpuid_phys variable for ppc64, to be consistent we use get_hard_smp_processor_id(boot_cpuid) everywhere. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc/pseries: Cleanup device name printing.Linas Vepstas
This avoids printk'ing a NULL string. Signed-off-by: Linas Vepstas <linas@linas.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] spufs: Fix endless protection fault on LS writes by SPE.Arnd Bergmann
If an SPE attempts a DMA put to a local store after already doing a get, the kernel must update the HW PTE to allow the write access. This case was not being handled correctly. From: Mike Kistler <mkistler@us.ibm.com> Signed-off-by: Mike Kistler <mkistler@us.ibm.com> Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: use guarded ioremap for cell on-chip mappingsArnd Bergmann
I'm not sure where the information came from, but I assumed that doing cache-inhibited mappings for mmio regions was sufficient. It seems we also need the guarded bit set, like everyone else, which is the default for ioremap. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: fix spider-pic affinity settingArnd Bergmann
As noticed by Milton Miller, setting the initial affinity in spider-pic can go wrong if the target node field was not orinally empty. Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: dynamic probe - use ppc_md.pci_probe_mode()John Rose
Change the dynamic PCI probe function for pSeries to use ppc_md.pci_probe_mode() when appropriate. Signed-off-by: John Rose <johnrose@austin.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: return to OF via trap, not exitOlaf Hering
Do not call prom exit prom_panic. It clears the screen and the exit message is lost. On some (or all?) pmacs it causes another crash when OF tries to print the date and time in its banner. Set of_platform earlier to catch more prom_panic() calls. Signed-off-by: Olaf Hering <olh@suse.de> Acked-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: hot_add_scn_to_nid() build fixAndrew Morton
The return statement is to prevent `warning: 'nid' might be used uninitialized in this function'. Cc: Nathan Lynch <nathanl@austin.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] correct the comment about stackpointer alignment in __boot_from_promOlaf Hering
The address of variable val in prom_init_stdout is passed to prom_getprop. prom_getprop casts the pointer to u32 and passes it to call_prom in the hope that OpenFirmware stores something there. But the pointer is truncated in the lower bits and the expected value is stored somewhere else. In my testing I had a stackpointer of 0x0023e6b4. val was at offset 120, wich has address 0x0023e72c. But the value passed to OF was 0x0023e728. c00000000040b710: 3b 01 00 78 addi r24,r1,120 ... c00000000040b754: 57 08 00 38 rlwinm r8,r24,0,0,28 ... c00000000040b784: 80 01 00 78 lwz r0,120(r1) ... c00000000040b798: 90 1b 00 0c stw r0,12(r27) ... The stackpointer came from 32bit code. The chain was yaboot -> zImage -> vmlinux PowerMac OpenFirmware does appearently not handle the ELF sections correctly. If yaboot was compiled in /usr/src/packages/BUILD/lilo-10.1.1/yaboot, then the stackpointer is unaligned. But the stackpointer is correct if yaboot is compiled in /tmp/yaboot. This bug triggered since 2.6.15, now prom_getprop is an inline function. gcc clears the lower bits, instead of just clearing the upper 32 bits. Signed-off-by: Olaf Hering <olh@suse.de> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] spufs: initialize context correctlyDirk Herrendoerfer
the mfc member of a new context was not initialized to zero, which potentially leads to wild memory accesses. Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] spufs: enable SPE problem state MMIO access.Mark Nutter
This patch is layered on top of CONFIG_SPARSEMEM and is patterned after direct mapping of LS. This patch allows mmap() of the following regions: "mfc", which represents the area from [0x3000 - 0x3fff]; "cntl", which represents the area from [0x4000 - 0x4fff]; "signal1" which begins at offset 0x14000; "signal2" which begins at offset 0x1c000. The signal1 & signal2 files may be mmap()'d by regular user processes. The cntl and mfc file, on the other hand, may only be accessed if the owning process has CAP_SYS_RAWIO, because they have the potential to confuse the kernel with regard to parallel access to the same files with regular file operations: the kernel always holds a spinlock when accessing registers in these areas to serialize them, which can not be guaranteed with user mmaps, Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] spufs: implement mfc access for PPE-side DMAArnd Bergmann
This patch adds a new file called 'mfc' to each spufs directory. The file accepts DMA commands that are a subset of what would be legal DMA commands for problem state register access. Upon reading the file, a bitmask is returned with the completed tag groups set. The file is meant to be used from an abstraction in libspe that is added by a different patch. From the kernel perspective, this means a process can now offload a memory copy from or into an SPE local store without having to run code on the SPE itself. The transfer will only be performed while the SPE is owned by one thread that is waiting in the spu_run system call and the data will be transferred into that thread's address space, independent of which thread started the transfer. Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] spufs: allow SPU code to do syscallsArnd Bergmann
An SPU does not have a way to implement system calls itself, but it can create intercepts to the kernel. This patch uses the method defined by the JSRE interface for C99 host library calls from an SPU to implement Linux system calls. It uses the reserved SPU stop code 0x2104 for this, using the structure layout and syscall numbers for ppc64-linux. I'm still undecided wether it is better to have a list of allowed syscalls or a list of forbidden syscalls, since we can't allow an SPU to call all syscalls that are defined for ppc64-linux. This patch implements the easier choice of them, with a blacklist that only prevents an SPU from calling anything that interacts with its own execution, e.g fork, execve, clone, vfork, exit, spu_run and spu_create and everything that deals with signals. Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: declare arch syscalls in <asm/syscalls.h>Arnd Bergmann
powerpc currently declares some of its own system calls in <asm/unistd.h>, but not all of them. That place also contains remainders of the now almost unused kernel syscall hack. - Add a new <asm/syscalls.h> with clean declarations - Include that file from every source that implements one of these - Get rid of old declarations in <asm/unistd.h> This patch is required as a base for implementing system calls from an SPU, but also makes sense as a general cleanup. Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: work around a cell interrupt HW bugArnd Bergmann
Apparently we have found a bug in the CPU that causes external interrupts to sometimes get disabled indefinitely. This adds a workaround for the problem. Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: cell interrupt controller updatesJens Osterkamp
The current interrupt controller setup on Cell is done in a rather ad-hoc way with device tree properties that are not standardized at all. In an attempt to do something that follows the OF standard (or at least the IBM extensions to it) more closely, we have now come up with this patch. It still provides a fallback to the old behaviour when we find older firmware, that hack can not be removed until the existing customer installations have upgraded. Cc: hpenner@de.ibm.com Cc: stk@de.ibm.com Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: Milton Miller <miltonm@bga.com> Cc: benh@kernel.crashing.org Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: update cell defconfigArnd Bergmann
The default configuration in mainline got a little out of sync with what we use internally. Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: fix cell iommu setupArnd Bergmann
A small bug crept in the iommu driver when we made it more generic. This patch is needed for boards that have a dma window that does not start at bus address zero. Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: Change firmware_has_feature() to a macroMichael Ellerman
So that we can use firmware_has_feature() in a BUG_ON() and have the compiler elide the code entirely if the feature can never be set, change firmware_has_feature to a macro. Unfortunate, but necessary at least until GCC bug #26724 is fixed. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: Make BUG_ON & WARN_ON play nice with compile-time optimisationsMichael Ellerman
Change BUG_ON and WARN_ON to give the compiler a chance to perform compile-time optimsations. Depending on the complexity of the condition, the compiler may not do this very well, so if it's important check the object code. Current GCC's (4.x) produce good code as long as the condition does not include a function call, including a static inline. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: fix various sparse warningsStephen Rothwell
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-27[PATCH] powerpc: work around sparse warnings in cputable.hStephen Rothwell
Christoph noticed that sparse warned about all the enum tags in cuptable.h that had values that required them to be type log. (enum tags are ints according to the standard.) This patch attempts to fix them in the least intrusive way possible by turning them all into #defines except for the 32 bit CPU_FTRS_POSSIBLE and CPU_FTRS_ALWAYS which are hard to construct that way. This works because these last two contain no bits above 2^31. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-26[SPARC64]: Kill duplicate exports of string library functions.David S. Miller
Kbuild now points these out. Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-26[SPARC64]: Update defconfig.David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-26[PATCH] one ipc/sem.c->mutex.c converstion too many..Manfred Spraul
Ingo's sem2mutex patch incorrectly replaced one reference to ipc/sem.c with ipc/mutex.c in a comment. Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivialLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: drivers/char/ftape/lowlevel/fdc-io.c: Correct a comment Kconfig help: MTD_JEDECPROBE already supports Intel Remove ugly debugging stuff do_mounts.c: Minor ROOT_DEV comment cleanup BUG_ON() Conversion in drivers/s390/block/dasd_devmap.c BUG_ON() Conversion in mm/mempool.c BUG_ON() Conversion in mm/memory.c BUG_ON() Conversion in kernel/fork.c BUG_ON() Conversion in ipc/sem.c BUG_ON() Conversion in fs/ext2/ BUG_ON() Conversion in fs/hfs/ BUG_ON() Conversion in fs/dcache.c BUG_ON() Conversion in fs/buffer.c BUG_ON() Conversion in input/serio/hp_sdc_mlc.c BUG_ON() Conversion in md/dm-table.c BUG_ON() Conversion in md/dm-path-selector.c BUG_ON() Conversion in drivers/isdn BUG_ON() Conversion in drivers/char BUG_ON() Conversion in drivers/mtd/
2006-03-26drivers/char/ftape/lowlevel/fdc-io.c: Correct a commentBastien Roucaries
This patch correct a comment about cli(). Signed-off-by: Bastien Roucaries <roucaries.bastien@gmail.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-26Kconfig help: MTD_JEDECPROBE already supports IntelAdrian Bunk
Intel chips are already supported. Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: David Woodhouse <dwmw2@infradead.org>
2006-03-26[PATCH] bitops: hweight() speedupAkinobu Mita
<linux@horizon.com> wrote: This is an extremely well-known technique. You can see a similar version that uses a multiply for the last few steps at http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel whch refers to "Software Optimization Guide for AMD Athlon 64 and Opteron Processors" http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/25112.PDF It's section 8.6, "Efficient Implementation of Population-Count Function in 32-bit Mode", pages 179-180. It uses the name that I am more familiar with, "popcount" (population count), although "Hamming weight" also makes sense. Anyway, the proof of correctness proceeds as follows: b = a - ((a >> 1) & 0x55555555); c = (b & 0x33333333) + ((b >> 2) & 0x33333333); d = (c + (c >> 4)) & 0x0f0f0f0f; #if SLOW_MULTIPLY e = d + (d >> 8) f = e + (e >> 16); return f & 63; #else /* Useful if multiply takes at most 4 cycles */ return (d * 0x01010101) >> 24; #endif The input value a can be thought of as 32 1-bit fields each holding their own hamming weight. Now look at it as 16 2-bit fields. Each 2-bit field a1..a0 has the value 2*a1 + a0. This can be converted into the hamming weight of the 2-bit field a1+a0 by subtracting a1. That's what the (a >> 1) & mask subtraction does. Since there can be no borrows, you can just do it all at once. Enumerating the 4 possible cases: 0b00 = 0 -> 0 - 0 = 0 0b01 = 1 -> 1 - 0 = 1 0b10 = 2 -> 2 - 1 = 1 0b11 = 3 -> 3 - 1 = 2 The next step consists of breaking up b (made of 16 2-bir fields) into even and odd halves and adding them into 4-bit fields. Since the largest possible sum is 2+2 = 4, which will not fit into a 4-bit field, the 2-bit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ "which will not fit into a 2-bit field" fields have to be masked before they are added. After this point, the masking can be delayed. Each 4-bit field holds a population count from 0..4, taking at most 3 bits. These numbers can be added without overflowing a 4-bit field, so we can compute c + (c >> 4), and only then mask off the unwanted bits. This produces d, a number of 4 8-bit fields, each in the range 0..8. From this point, we can shift and add d multiple times without overflowing an 8-bit field, and only do a final mask at the end. The number to mask with has to be at least 63 (so that 32 on't be truncated), but can also be 128 or 255. The x86 has a special encoding for signed immediate byte values -128..127, so the value of 255 is slower. On other processors, a special "sign extend byte" instruction might be faster. On a processor with fast integer multiplies (Athlon but not P4), you can reduce the final few serially dependent instructions to a single integer multiply. Consider d to be 3 8-bit values d3, d2, d1 and d0, each in the range 0..8. The multiply forms the partial products: d3 d2 d1 d0 d3 d2 d1 d0 d3 d2 d1 d0 + d3 d2 d1 d0 ---------------------- e3 e2 e1 e0 Where e3 = d3 + d2 + d1 + d0. e2, e1 and e0 obviously cannot generate any carries. Signed-off-by: Akinobu Mita <mita@miraclelinux.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26Remove ugly debugging stuffArtem B. Bityuckiy
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-26[PATCH] bitops: hweight() related cleanupAkinobu Mita
By defining generic hweight*() routines - hweight64() will be defined on all architectures - hweight_long() will use architecture optimized hweight32() or hweight64() I found two possible cleanups by these reasons. Signed-off-by: Akinobu Mita <mita@miraclelinux.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>