The changes to the device node structure broke Maple build. This fixes it.
Unfortunately I coudn't test as my Maple board appears to be dead.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes CHRP build again, although it's untested because my Pegasos
is currently in pieces.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add the first MPC83xx board that uses a flat device tree to arch/powerpc.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At present the lppaca - the structure shared with the iSeries
hypervisor and phyp - is contained within the PACA, our own low-level
per-cpu structure. This doesn't have to be so, the patch below
removes it, making a separate array of lppaca structures.
This saves approximately 500*NR_CPUS bytes of image size and kernel
memory, because we don't need aligning gap between the Linux and
hypervisor portions of every PACA. On the other hand it means an
extra level of dereference in many accesses to the lppaca.
The patch also gets rid of several places where we assign the paca
address to a local variable for no particular reason.
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add support to reconfigure the device tree through the existing
proc filesystem interface. Add "add_property", "remove_property",
and "update_property" commands to the existing interface.
Signed-off-by: Dave Boutcher <sleddog@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
These symbols are only used in the file that they are defined in,
so they should not be in the global namespace.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
pmac_setup_arch is only used in the file that it is defined in,
so it should not be in the global namespace.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
These symbols are only used in the file that they are defined in,
so they should not be in the global namespace.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
There was a function declared for CONFIG_PSERIES which no longer exists
and the two function declarations for CONFIG_ISERIES have been moved
into an include file in platforms/iseries since they are defined and
used only there.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This reverts part of "ppc64 iSeries: allow build with no PCI"
(145d01e428) which affected generic code
and applies a fix in the arch specific code.
Commit "partly merge iseries do_IRQ"
(5fee9b3b39eb55c7e3619a3b36ceeabffeb8f144) introduced iSeries_get_irq
which was only available if CONFIG_PCI is set.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove warning in eeh code about mixed variables and code.
Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
iSeries doesn't need to set the htab_address explicitly, htab_initialize()
will do it for us later.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
To make iSeries just a teensy bit less special, create ibm,pft-size properties
in the iSeries device tree. We can then rely on htab_dt_scan_pftsize() to set
ppc64_pft_size for us.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Updated Kconfig & Makefiles in prep for adding support for the Freescale
MPC83xx family of processors to arch/powerpc. Moved around some config
options that are more globally applicable to other PowerPC processors.
Added a temporary config option (83xx) to match existing arch/ppc support
for the MPC83xx line.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The SPE Book IV indicates that MFC DMA operations must be
suspended and restored on SPU context switch (in Step 8).
This patch adds that operation, which is missing from the
current spufs implementation.
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch adds Kconfig entries to control the early debugging options,
currently in setup_64.c.
Doing this via Kconfig rather than #defines means you can have one source tree,
which is buildable for multiple platforms - and you can enable the correct
early debug option for each platform via .config.
I made udbg_early_init() a static inline because otherwise GCC is to daft to
optimise it away when debugging is off.
Now that we have udbg_init_rtas() we can make call_rtas_display_status* static.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Connect iSeries up to the standard early debugging infrastructure.
To actually use this you need to enable the iSeries early debugging
in setup_64.c. Then after the messages are logged hit Ctrl-x Ctrl-x on
your console to dump the Hypervisor console buffer.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The previous change by Kumar Gala in this area led to legacy_serial.c
and udbg_16550.c being built as modules when CONFIG_SERIAL_8250=m.
Fix this by introducing a new symbol, CONFIG_PPC_UDBG_16550, to
control whether these files get built, and arrange for it to be selected
for those platforms that need it.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes a crash on null-pointer deref during dlpar slot addition.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from 1c87c0f84943fbbc91826967ff4fea1b059a526f commit)
<asm/systemcfg.h> is gone now, and the PCI error recovery constants
in include/linux/pci.h changed their names in the process of getting
accepted.
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from 5a2516156c591fc3d2059fbd93f97e15eb6010d6 commit)
242-eeh-no-percpu-counters.patch
Remove per-cpu counters from the EEH code. These statistics counters
are incremented at a very low frequency, and the performance gains of
per-cpu variables are negligable. By contrast, the counters weren't
safe against cpu off/online operations, and its not worth the effort
to make them so (other than to turn them into plain globals).
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from be3b5d1be053ccb41e91fa5a6f43ef5db301357d commit)
241-eeh-save-bars-earlier.patch
Save the PCI device bars *before* any PCI probing is done.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from 76c902b919098860f3d4e125f847abcc4cb1782a commit)
239-eeh-multifunction-consolidate.patch
New-style firmware will often place multiple different functions
under a non-EEH-aware parent. However, these devices might share
a common PE "partition endpoint" and config address, ad thus any
EEH events will affect all of the devices in common. This patch
makes the effort to find all of these common devices and handle
them together.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from 216810296bb97d39da8e176822e9de78d2f00187 commit)
238-eeh-stop-if-reset_failed.patch
If the firmware is unable to reset the PCI slot for some reason, then
don't attempt any further recovery steps after that point. Instead,
mark the device as permanently failed.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from e06b942521eb2cdaf232726f45a820d5837acb12 commit)
237-eeh-bridge-token.patch
Minor: the rtas-bridge token should be set up the same way that all
the other rtas tokens are set up.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from 78379b6c5fc17b6666c40b05988e6708e98479c0 commit)
236-eeh-config-addr.patch
The PE configuration address wasn't being cnsistently used in all locations
where a config address is called for. This patch adds it to the places it
should have appeared in.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from c2bc904a28095aca0b04a37854b63b78622a032e commit)
235-eeh-set-pcidev-bugfix.patch
The pci device field of the pci_dn struct should be initialized to a
valid value.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from beb45c93d494a11c36e5b24f638e610db8428b54 commit)
234-eeh-find-pe.patch
The find_device_pe() routine is duplicated in two files. Remove one of
the two copies, declare the other extern.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from 48408e708282d4d0269136ff27ea5acbd9410b5a commit)
26-eeh-partition-endpoint.patch
New versions of firmware introduce a new method by which the
"partitionable endpoint" (the point at which the pci bus is cut)
should be located. This code adds the support for this (mandatory)
new feature.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from 9fcfb5d35b5294659f9299aa9cae6fd16325c07e commit)
25-pci-address-cache.patch
The core EEH file is rather large. This patch splits out a self-contained
chunk of it into its own file. This is the chunk that performes the
caching and lookup of pci devices based on the i/o addresses of thier
resoures. This code is almos architecture-independent and could be
used by any system that wanted to find a pci device based only on
the i/o address used by the device.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from b0b291d59906d4a9a89ed9e34d9fd684c7188924 commit)
Various PCI bus errors can be signaled by newer PCI controllers. The
core error recovery routines are architecture dependent. This patch adds
a recovery infrastructure for the PPC64 pSeries systems.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
(cherry picked from e8ca11b460c4c9c7fa6b529be221529ebd770e38 commit)
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.
Modified-by: Ingo Molnar <mingo@elte.hu>
(finished the conversion)
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds cpufreq support for all desktop "tower" G5 models. The
only G5 models still lacking cpufreq support at this point are the
Xserve and possibly the new iMac iSight (not tested). I'll have those
added soon. That patch uses the new platform functions interpreter to
implement frequency and voltage switching on most models.
Note that in order to find the low frequency value, I had to hack
something that might now work properly on all models, so if the
frequency value reported when running low speed looks bogus to you,
please report it to me. (Appart from a bogus reported value, things
should work fine).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This is the platform function interpreter itself along with the backends
for UniN/U3/U4, mac-io, GPIOs and i2c. It adds the ability to execute
those do-platform-* scripts in the device-tree (at least for most
devices for which a backend is provided). This should replace the clock
spreading hacks properly. It might also have an impact on all sort of
machines since some of the scripts marked "at init" will now be executed
on boot (or some other on sleep/wakeup), those will possibly do things
that the kernel didn't do at all, like setting some values into some i2c
devices (changing thermal sensor calibration or conversion rate) etc...
Thus regression testing is MUCH welcome. Also loook for errors in dmesg.
That's also why I've left rather verbose debugging enabled in this
version of the patch.
(I do expect some Windtunnel G4s to show some errors as they have an i2c
clock chip on the PMU bus that uses some primitives that the i2c backend
doesn't implement yet. I really need users that have one of those
machine to come back to me so we can get that done right, though the
errors themselves should be harmless, I suspect the machine might not
run at full speed).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This is the continuation of the previous patch. This one removes the old
PowerMac i2c drivers (i2c-keywest and i2c-pmac-smu) and replaces them
both with a single stub driver that uses the new PowerMac low i2c layer.
Now that i2c-keywest is gone, the low-i2c code is extended to support
interrupt driver transfers. All i2c busses now appear as platform
devices. Compatibility with existing drivers should be maintained as the
i2c bus names have been kept identical, except for the SMU bus but in
that later case, all users has been fixed.
With that patch added, matching a device node to an i2c_adapter becomes
trivial.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This is the first part of a rework of the PowerMac i2c code. It
completely reworks the "low_i2c" layer. It is now more flexible,
supports KeyWest, SMU and PMU i2c busses, and provides functions to
match device nodes to i2c busses and adapters.
This patch also extends & fix some bugs in the SMU driver related to i2c
support and removes the clock spreading hacks from the pmac feature code
rather than adapting them to the new API since they'll be replaced by
the platform function code completely in patch 3/5
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
For far, all SPU triggered interrupts always end up on
the first SMT thread, which is a bad solution.
This patch implements setting the affinity to the
CPU that was running last when entering execution on
an SPU. This should result in a significant reduction
in IPI calls and better cache locality for SPE thread
specific data.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
One local variable is missing an __iomem modifier,
in another place, we pass a completely unused argument
with a missing __user modifier.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In a hypervisor based setup, direct access to the first
priviledged register space can typically not be allowed
to the kernel and has to be implemented through hypervisor
calls.
As suggested by Masato Noguchi, let's abstract the register
access trough a number of function calls. Since there is
currently no public specification of actual hypervisor
calls to implement this, I only provide a place that
makes it easier to hook into.
Cc: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Cc: Geoff Levand <geoff.levand@am.sony.com>
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The logic for sys_spu_run keeps growing and it does
not really belong into file.c any more since we
moved away from using regular file operations to our
own syscall.
No functional change in here.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
checking bits manually might not be synchonized with
the use of set_bit/clear_bit. Make sure we always use
the correct bitops by removing the unnecessary
identifiers.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
If creating one entry failed in spufs_fill_dir,
we never cleaned up the freshly created entries.
Fix this by calling the cleanup function on error.
Noticed by Al Viro.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
If get_unused_fd failed in sys_spu_create, we never cleaned
up the created directory. Fix that by restructuring the
error path.
Noticed by Al Viro.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When spu_activate fails in spu_acquire_runnable, the
state must still be SPU_STATE_SAVED, we were
incorrectly setting it to SPU_STATE_RUNNABLE.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
During an earlier cleanup, we lost the serialization
of multiple spu_run calls performed on the same
spu_context. In order to get this back, introduce a
mutex in the spu_context that is held inside of spu_run.
Noticed by Al Viro.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Only checking for SPUFS_MAGIC is not reliable, because
it might not be unique in theory. Worse than that,
we accidentally allow spu_run to be performed on
any file in spufs, not just those returned from
spu_create as intended.
Noticed by Al Viro.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
spu_forget will do mmput on the DMA address space,
which can lead to lots of other stuff getting triggered.
We better not hold a semaphore here that we might
need in the process.
Noticed by Al Viro.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We need to check for validity of owner under down_write,
down_read is not enough.
Noticed by Al Viro.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch enables support for pause(0) power management state
for the Cell Broadband Processor, which is import for power efficient
operation. The pervasive infrastructure will in the future enable
us to introduce more functionality specific to the Cell's
pervasive unit.
From: Maximino Aguilar <maguilar@us.ibm.com>
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At present, we are not looking at all interrupt controller nodes in the
device tree even though the proper node was not found. This is causing
the system panic. The attached patch will scan all nodes until it finds
the proper interrupt controller type.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Added a common udbg_progress for use by ppc_md.progress()
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds some very basic support for the new machines, including the
Quad G5 (tested), and other new dual core based machines and iMac G5
iSight (untested). This is still experimental ! There is no thermal
control yet, there is no proper handing of MSIs, etc.. but it
boots, I have all 4 cores up on my machine. Compared to the previous
version of this patch, this one adds DART IOMMU support for the U4
chipset and thus should work fine on setups with more than 2Gb of RAM.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
There is code in the RPAPHP directory that is identical to this routine;
I'll be removing that code in an upcoming patch, but this patch is needed
to expose the function to make it callable.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The pre-parsed addrs/n_addrs fields in struct device_node are finally
gone. Remove the dodgy heuristics that did that parsing at boot and
remove the fields themselves since we now have a good replacement with
the new OF parsing code. This patch also fixes a bunch of drivers to use
the new code instead, so that at least pmac32, pseries, iseries and g5
defconfigs build.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We currently crash in the fedora installer because the keyboard
driver tries to access I/O space that is not there on our hardware.
This uses the same solution as powermac by just marking all
legacy i/o as invalid.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
So far, the iommu code was hardwired to a linear mapping
between 0x20000000 and 0x40000000, so it could only support
512MB of RAM.
This patch still keeps the linear mapping, but looks for
proper ibm,dma-window properties to set up larger windows,
this makes the maximum supported RAM size 2GB.
If there is anything unusual about the dma-window properties,
we fall back to the old behavior.
We also support switching off the iommu completely now
with the regular iommu=off command line option.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Output from hexdump with "%08x" depends on HOST platform's endian.
When building linux by cross toolchain, that difference makes errors.
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Geoff Levand <geoff.levand@am.sony.com>
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
One of my last patches contained a broken line
from splitting out some other changes, this
restores a working version.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
One of the two users of spufs_calls.owner still has a race
when calling try_module_get while the module is removed.
This makes it use the correct instance of owner.
Noticed by Milton Miller.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Handling mailbox interrupts was broken in multiple respects,
the combination of which was hiding the bugs most of the time.
- The ibox interrupt mask was open initially even though there
are no waiters on a newly created SPU.
- Acknowledging the mailbox interrupt did not work because
it is level triggered and the mailbox data is never retrieved
from inside the interrupt handler.
- The interrupt handler delivered interrupts with a disabled
mask if another interrupt is triggered for the same class
but a different mask.
- The poll function did not enable the interrupt if it had not
been enabled, so we might run into the poll timeout if none of
the other bugs saved us and no signal was delivered.
We probably still have a similar problem with blocking
read/write on mailbox files, but that will result in extra
wakeup in the worst case, not in incorrect behaviour.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch reduces lock complexity of SPU scheduler, particularly
for involuntary preemptive switches. As a result the new code
does a better job of mapping the highest priority tasks to SPUs.
Lock complexity is reduced by using the system default workqueue
to perform involuntary saves. In this way we avoid nasty lock
ordering problems that the previous code had. A "minimum timeslice"
for SPU contexts is also introduced. The intent here is to avoid
thrashing.
While the new scheduler does a better job at prioritization it
still does nothing for fairness.
From: Mark Nutter <mnutter@us.ibm.com>
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch makes it easier to preempt an SPU context by
having the scheduler hold ctx->state_sema for much shorter
periods of time.
As part of this restructuring, the control logic for the "run"
operation is moved from arch/ppc64/kernel/spu_base.c to
fs/spufs/file.c. Of course the base retains "bottom half"
handlers for class{0,1} irqs. The new run loop will re-acquire
an SPU if preempted.
From: Mark Nutter <mnutter@us.ibm.com>
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
spufs is rather noisy when debugging is enabled, this
turns off the messages for production use.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
try_module_get returns true when NULL arguments, so
we first need to check if there is a module loaded before
getting the reference count.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
With the new rules for reserved pages, the spufs now
needs working page reference counting.
I should probably look into converting to vm_insert_page,
but for now this patch makes spufs work again.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This changes all exported symbols of spufs to EXPORT_SYMBOL_GPL.
The spu_ibox_read/spu_wbox_write symbols are not exported
any more when the scheduler patch is applied.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Implementing the machine_crash_shutdown which will be called by
crash_kexec (called in case of a panic, sysrq etc.). Disable the
interrupts, shootdown cpus using debugger IPI and collect regs
for all CPUs.
elfcorehdr= specifies the location of elf core header stored by
the crashed kernel. This command line option will be passed by
the kexec-tools to capture kernel.
savemaxmem= specifies the actual memory size that the first kernel
has and this value will be used for dumping in the capture kernel.
This command line option will be passed by the kexec-tools to
capture kernel.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
There's a few places where we need to fix things up for the kernel to work
if it's linked at 32MB:
- platforms/powermac/smp.c
To start secondary cpus on pmac we patch the reset vector, which is fine.
Except if we're above 32MB we don't have enough bits for an absolute branch,
it needs to relative.
- kernel/head_64.s
- A few branches in the cpu hold code need to load the full target address
and do a bctr.
- after_prom_start needs to load PHYSICAL_START as the dest address, not 0.
- The exception prolog needs to load the low word of the target adddress,
not just the low halfword.
- Fixup handling of the initial stab address.
- kernel/setup_64.c
smp_release_cpus() needs to write 1 to the spinloop flag near 0, not 32 MB.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The fwnmi vectors can be anywhere < 32 MB, so we need to use a trampoline
for them. The kdump kernel will register the trampoline addresses, which will
then jump up to the real code above 32 MB.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Minor: use macro to perform void pointer deref; this may someday help
avoid pointer typecasting errors.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This updates the OF address parsers to return the IO flags
indicating the type of address obtained. It also adds a PCI
call for converting physical addresses that hit IO space into
into IO tokens, and add routines that return the translated
addresses into struct resource
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The udbg low level io layer has an issue with udbg_getc() returning a
char (unsigned on ppc) instead of an int, thus the -1 if you had no
available input device could end up turned into 0xff, filling your
display with bogus characters. This fixes it, along with adding a little
blob to xmon to do a delay before exiting when getting an EOF and fixing
the detection of ADB keyboards in udbg_adb.c
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When compiling without BOOTX_TEXT the following warning is emitted.
Fix up the definition to only be made when required.
CC arch/powerpc/platforms/powermac/udbg_adb.o
.../arch/powerpc/platforms/powermac/udbg_adb.c:41: warning:
`udbg_adb_use_btext' defined but not used
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
udbg_adb_init() has become dependent on btext_drawchar, even when
BOOTX_TEXT support is not selected. This leads to the error below.
Make the check dependant on BOOTX_TEXT.
LD .tmp_vmlinux1
arch/powerpc/platforms/built-in.o(.toc1+0xa40): undefined
reference to `btext_drawchar'
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
23-rpaphp-migrate.patch (parts)
This patch moves some pci device add & remove code from the PCI
hotplug directory to the arch/powerpc/kernel directory, and cleans
it up a tad. The primary reason for this is that the code performs
some fairly generic operations that are shared with the PCI error
recovery code (living in the arch/powerpc/kernel directory).
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
20-rpaphp-eeh-cleanup.patch
This patch move some code from the rpaphp directory, to the powerpc
directory, where it should have been all along (Among other things, I
need it in the powerpc directory for the PCI error recovery.)
Please note that patch affects TWO maintainers: Paul, after applying
the powerpc part, please ask that GregKH appli the PCI part. It is safe
to have the powerpc part go in first. It would be bad to have the
PCI part go in first.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes the new serial probe code with some PCI MMIO UARTs, and fixes
CHRP build with ARCH=powerpc.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
My previous patches inadvertently broke building a G5 kernel with
CONFIG_XMON enabled. This fixes it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
On iSeries, the paca contains, amongst other things an ItLpRegSave
structure used by the hypervisor to save registers. The hypervisor
locates this area through a pointer at the beginning of the paca, so
the structure itself can be located elsewhere. This patch moves the
reg_save area out into its own array. This reduces the amount of
iSeries specific gunk which is visible to general powerpc code via
paca.h
Built and booted on POWER5 LPAR and iSeries RS64.
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Encode the sub bus number into the real irq number (even though it
is always zero for now) so that we have enough information to do
the EOI in iseries_end_IRQ.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
ARCH=powerpc couldn't boot from BootX as it uses a "different" way of
getting in the kernel. This patch adds the necessary trampolines,
creating a flattened device-tree from the tree passed from MacOS, and
initializing the btext engine early for really-early debugging.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch unifies udbg for both ppc32 and ppc64 when building the
merged achitecture. xmon now has a single "back end". The powermac udbg
stuff gets enriched with some ADB capabilities and btext output. In
addition, the early_init callback is now called on ppc32 as well,
approx. in the same order as ppc64 regarding device-tree manipulations.
The init sequences of ppc32 and ppc64 are getting closer, I'll unify
them in a later patch.
For now, you can force udbg to the scc using "sccdbg" or to btext using
"btextdbg" on powermacs. I'll implement a cleaner way of forcing udbg
output to something else than the autodetected OF output device in a
later patch.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This moves the discovery of legacy serial ports to a separate file,
makes it common to ppc32 and ppc64, and reworks it to use the new OF
address translators to get to the ports early. This new version can also
detect some PCI serial cards using legacy chips and will probably match
those discovered port with the default console choice.
Only ppc64 gets udbg still yet, unifying udbg isn't finished yet.
It also adds some speed-probing code to udbg so that the default console
can come up at the same speed it was set to by the firmware.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds a scheduler for SPUs to make it possible to use
more logical SPUs than physical ones are present in the
system.
Currently, there is no support for preempting a running
SPU thread, they have to leave the SPU by either triggering
an event on the SPU that causes it to return to the
owning thread or by sending a signal to it.
This patch also adds operations that enable accessing an SPU
in either runnable or saved state. We use an RW semaphore
to protect the state of the SPU from changing underneath
us, while we are holding it readable. In order to change
the state, it is acquired writeable and a context save
or restore is executed before downgrading the semaphore
to read-only.
From: Mark Nutter <mnutter@us.ibm.com>,
Uli Weigand <Ulrich.Weigand@de.ibm.com>
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add the source code that is used to generate spu_save_dump.h and
spu_restore_dump.h. Since a full spu tool chain is needed to
generate these files, the default remains to use the shipped
versions in order to keep the number of tools for building the
kernel down.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds the code needed to perform a context switch from
spufs, following the recommended 76-step sequence.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add some infrastructure for saving and restoring the context of an
SPE. This patch creates a new structure that can hold the whole
state of a physical SPE in memory. It also contains code that
avoids races during the context switch and the binary code that
is loaded to the SPU in order to access its registers.
The actual PPE- and SPE-side context switch code are two separate
patches.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This is the current version of the spu file system, used
for driving SPEs on the Cell Broadband Engine.
This release is almost identical to the version for the
2.6.14 kernel posted earlier, which is available as part
of the Cell BE Linux distribution from
http://www.bsc.es/projects/deepcomputing/linuxoncell/.
The first patch provides all the interfaces for running
spu application, but does not have any support for
debugging SPU tasks or for scheduling. Both these
functionalities are added in the subsequent patches.
See Documentation/filesystems/spufs.txt on how to use
spufs.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch merges, to some extent, the PPC32 and PPC64 kexec implementations.
We adopt the PPC32 approach of having ppc_md callbacks for the kexec functions.
The current PPC64 implementation becomes the "default" implementation for PPC64
which platforms can select if they need no special treatment.
I've added these default callbacks to pseries/maple/cell/powermac, this means
iSeries no longer supports kexec - but it never worked anyway.
I've renamed PPC32's machine_kexec_simple to default_machine_kexec, inline with
PPC64. Judging by the comments it might be better named machine_kexec_non_of,
or something, but at the moment it's the only implementation for PPC32 so it's
the "default".
Kexec requires machine_shutdown(), which is in machine_kexec.c on PPC32, but we
already have in setup-common.c on powerpc. All this does is call
ppc_md.nvram_sync, which only powermac implements, so instead make
machine_shutdown a ppc_md member and have it call core99_nvram_sync directly
on powermac.
I've also stuck relocate_kernel.S into misc_32.S for powerpc.
Built for ARCH=ppc, and 32 & 64 bit ARCH=powerpc, with KEXEC=y/n. Booted on
P5 LPAR and successfully kexec'ed.
Should apply on top of 493f25ef40.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It turns out that commit f9bd170a87
broke the cascade from XICS to i8259 on pSeries machines; specifically
we ended up not ever doing the EOI on the XICS for the cascade. The
result was that interrupts from the serial ports (and presumably any
other devices using ISA interrupts) didn't get through. This fixes
it and also simplifies the code, by doing the EOI on the XICS in the
xics_get_irq routine after reading and acking the interrupt on the
i8259.
Signed-off-by: Paul Mackerras <paulus@samba.org>
The code that sets the clock spreading feature of the Intrepid ASIC
must not be run on some machine models or those won't boot. This
fixes it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Some debug code wasn't properly removed from the initial 64k pages
patch, and while it's harmless, it's also slowing down significantly a
very hot code path, thus it should really be removed.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The previous commit will use the page-at-a-time hypervisor call for
setting up IOMMU entries when we are using 64k pages and setting up
one 64k page, even though that means 16 calls to the hypervisor, since
the hypervisor still works on 4k pages. This optimizes this case by
using the multi-page IOMMU setup hypervisor call instead.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Must adjust tcenum and npages by TCE_PAGE_FACTOR to convert between
64KB pages and TCE (4K) pages. (This is done in other places, except
for this one location.)
Signed-off-by: Michal Ostrowski <mostrows at watson ibm com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Email address update, changing old work address to personal (permanent)
one.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We were using udelay in the loop on the primary cpu waiting for the
secondary cpu to take the timebase value. Unfortunately now that
udelay uses the timebase, and the timebase is stopped at this point,
the udelay never terminated. This fixes it by not using udelay, and
increases the number of loops before we time out to compensate.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes 32-bit CHRP systems use the RTAS time-of-day routines if
available. It fixes a bug in the RTAS time-of-day routines where they
were storing a 64-bit timebase value in an unsigned long by making
those variables u64. Also, the direct-access time-of-day routines
had the wrong convention for the month and year in the struct rtc_time.
Signed-off-by: Paul Mackerras <paulus@samba.org>
pseries_dedicated_idle() was using __get_tb which used to be defined
in asm/delay.h. Change it to use get_tb from asm/time.h, which is
in fact exactly the same thing.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Reserve the Maple RTC I/O resource. Needed now we use genrtc.
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
If the kernel supports both G5 and pSeries, and CONFIG_EEH is enabled,
eeh_init() is (quite reasonably) never called when we boot on a G5. Yet
eeh_check_failure() still gets called. We should avoid doing that if
!eeh_subsystem_enabled.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Hi,
The previous PowerBook patch didn't contain the feature table updates
for ARCH=powerpc. Here they are.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
I discovered that in some cases (PowerMac for example) we wouldn't
properly map the PCI IO space on recent kernels. In addition, the code
for initializing PCI host bridges was scattered all over the place with
some duplication between platforms.
This patch fixes the problem and does a small cleanup by creating a
pcibios_alloc_controller() in pci_64.c that is similar to the one in
pci_32.c (just takes an additional device node argument) that takes care
of all the grunt allocation and initialisation work. It should work for
both boot time and dynamically allocated PHBs.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Also deletes files in arch/ppc64 that are no longer used now that
we don't compile with ARCH=ppc64 any more.
Signed-off-by: Paul Mackerras <paulus@samba.org>
log_plpar_hcall_return is only used on PPC_PSERIES, so move
it closer to its users and inside ifdef CONFIG_PPC_PSERIES.
remove the last vestiges of systemcfg in iSeries.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
This moves the rtas RTC callbacks to rtas-rtc.c in arch/powerpc/kernel,
and kills the rest of arch/ppc64/kernel/rtc.c which was just a duplicate
of the genrtc functionality. Also enable build of genrtc for
CONFIG_PPC64 (it just works are we already have the required callbacks)
and enable it in all defconfigs.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes various errors in the new functions added in the vDSO's,
I've now verified all functions on both 32 and 64 bits vDSOs. It also
fix a sign extension bug getting the initial time of day at boot that
could cause the monotonic clock value to be completely on bogus for
64 bits applications (with either the vDSO or the syscall) on
powermacs.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We currently have a ppc_md member called cpu_irq_down, which disables IRQs
for the cpu in question. The only caller of cpu_irq_down is the kexec code.
On pSeries we need to do more than just teardown IRQs at kexec time, so rename
the ppc_md member to kexec_cpu_down and expand it. The pSeries code needs to
know, and other platforms might too, whether we're doing a crash shutdown (ie.
panicking) or a regular kexec, so add a flag for that.
The pSeries implementation of kexec_cpu_down does an unregister VPA call, which
tells the Hypervisor to stop writing stuff into our pacas. Without this we can
get weird memory corruption bugs when we kexec, caused by the Hypervisor
writing into the first kernel's pacas which happens to be somewhere interesting
in the second kernel's memory.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We needed the VDSO symbols in the arch/ppc asm-offsets.c, and there
were a few usages of _systemcfg still left lying around.
Signed-off-by: Paul Mackerras <paulus@samba.org>
We have been printing the raw ppc64_firmware_features during boot. Since
we can work it out from the device tree, lets remove it.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
17-eeh-slot-marking-bug.patch
A device that experiences a PCI outage may be just one deivce out
of many that was affected. In order to avoid repeated reports of
a failure, the entire tree of affected devices should be marked
as failed. This patch marks up the entire tree.
Signed-off-by: Linas Vepstas <linas@linas.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This also make klimit have the same type on 32-bit as on 64-bit,
namely unsigned long, and defines and initializes it in one place.
Signed-off-by: Paul Mackerras <paulus@samba.org>
phbs_remap_io(), which maps the PCI IO space into the kernel virtual space,
is called too early on powermac, and thus doesn't work.
This fixes it by removing the call from all platforms and putting it back
into the ppc64 common code where it belongs, after the actual probing of
the bus.
That means that before that call, only the ISA IO space (if any) is mapped,
any PIO access (from quirks for example) will fail. This happens not to be
a problem for now, but we'll have to rework that code if it becomes one in
the future.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch merges platform codes. systemcfg->platform is no longer used,
systemcfg use in general is deprecated as much as possible (and renamed
_systemcfg before it gets completely moved elsewhere in a future patch),
_machine is now used on ppc64 along as ppc32. Platform codes aren't gone
yet but we are getting a step closer. A bunch of asm code in head[_64].S
is also turned into C code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch consolidates macros used to generate assembly for
compatibility across different CPUs or configs. A new header,
asm-powerpc/asm-compat.h contains the main compatibility macros. It
uses some preprocessor magic to make the macros suitable both for use
in .S files, and in inline asm in .c files. Headers (bitops.h,
uaccess.h, atomic.h, bug.h) which had their own such compatibility
macros are changed to use asm-compat.h.
ppc_asm.h is now for use in .S files *only*, and a #error enforces
that. As such, we're a lot more careless about namespace pollution
here than in asm-compat.h.
While we're at it, this patch adds a call to the PPC405_ERR77 macro in
futex.h which should have had it already, but didn't.
Built and booted on pSeries, Maple and iSeries (ARCH=powerpc). Built
for 32-bit powermac (ARCH=powerpc) and Walnut (ARCH=ppc).
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
scanlog.c is only compiled on pSeries. Thus, this patch moves it to
platforms/pseries.
Built and booted on pSeries LPAR (ARCH=powerpc and ARCH=ppc64). Built
for iSeries (ARCH=powerpc).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds code to work around some problems with old versions of
Open Firmware, such as on the early powermacs (7500 etc.) and the
"Longtrail" CHRP machine. On these machines we have to claim
the physical and virtual address ranges explicitly when claiming
memory and then set up a V->P mapping.
The Longtrail has more problems: setprop doesn't work, and we have
to set an "allow-reclaim" variable to 0 in order to get claim on
physical memory ranges to fail if the memory is already claimed.
Signed-off-by: Paul Mackerras <paulus@samba.org>
14-eeh-device-bar-save.patch
After a PCI device has been resest, the device BAR's and other config
space info must be restored to the same state as they were in when
the firmware first handed us this device. This will allow the
PCI device driver, when restarted, to correctly recognize and set up
the device.
Tis patch saves the device config space as early as reasonable after
the firmware has handed over the device. Te state resore funcion
is inteded for use by the EEH recovery routines.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
13-eeh-recovery-support-routines.patch
EEH Recovery support routines
This patch adds routines required to help drive the recovery of
EEH-frozen slots. The main function is to drive the PCI #RST
signal line high for a qurter of a second, and then allow for
a second & a half of settle time.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
12-eeh-event-dispatcher.patch
ppc64: EEH Recovery dispatcher thread
This patch adds a mechanism to create recovery threads when an
EEH event is received. Since an EEH freeze state may be detected
within an interrupt context, we need to get out of the interrupt
context before starting recovery. This dispatcher does this in
two steps: first, it uses a workqueue to get out, and then
lanuches a kernel thread, so that the recovery routine can
sleep for exteded periods without upseting the keventd.
A kernel thread is created with each EEH event, rather than
having one long-running daemon started at boot time. This is
because it is anticipated that EEH events will be very rare
(very very rare, ideally) and so its pointless to cluter the
process tables with a daemon that will almost never run.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
11-eeh-move-to-powerpc.patch
Move arch/ppc64/kernel/eeh.c to arch//powerpc/platforms/pseries/eeh.c
No other changes (except for Makefile to build it)
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Make some changes to the NEED_RESCHED and POLLING_NRFLAG to reduce
confusion, and make their semantics rigid. Improves efficiency of
resched_task and some cpu_idle routines.
* In resched_task:
- TIF_NEED_RESCHED is only cleared with the task's runqueue lock held,
and as we hold it during resched_task, then there is no need for an
atomic test and set there. The only other time this should be set is
when the task's quantum expires, in the timer interrupt - this is
protected against because the rq lock is irq-safe.
- If TIF_NEED_RESCHED is set, then we don't need to do anything. It
won't get unset until the task get's schedule()d off.
- If we are running on the same CPU as the task we resched, then set
TIF_NEED_RESCHED and no further action is required.
- If we are running on another CPU, and TIF_POLLING_NRFLAG is *not* set
after TIF_NEED_RESCHED has been set, then we need to send an IPI.
Using these rules, we are able to remove the test and set operation in
resched_task, and make clear the previously vague semantics of
POLLING_NRFLAG.
* In idle routines:
- Enter cpu_idle with preempt disabled. When the need_resched() condition
becomes true, explicitly call schedule(). This makes things a bit clearer
(IMO), but haven't updated all architectures yet.
- Many do a test and clear of TIF_NEED_RESCHED for some reason. According
to the resched_task rules, this isn't needed (and actually breaks the
assumption that TIF_NEED_RESCHED is only cleared with the runqueue lock
held). So remove that. Generally one less locked memory op when switching
to the idle thread.
- Many idle routines clear TIF_POLLING_NRFLAG, and only set it in the inner
most polling idle loops. The above resched_task semantics allow it to be
set until before the last time need_resched() is checked before going into
a halt requiring interrupt wakeup.
Many idle routines simply never enter such a halt, and so POLLING_NRFLAG
can be always left set, completely eliminating resched IPIs when rescheduling
the idle task.
POLLING_NRFLAG width can be increased, to reduce the chance of resched IPIs.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Run idle threads with preempt disabled.
Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()).
How did it ever work before?
Might fix the CPU hotplugging hang which Nigel Cunningham noted.
We think the bug hits if the idle thread is preempted after checking
need_resched() and before going to sleep, then the CPU offlined.
After calling stop_machine_run, the CPU eventually returns from preemption and
into the idle thread and goes to sleep. The CPU will continue executing
previous idle and have no chance to call play_dead.
By disabling preemption until we are ready to explicitly schedule, this bug is
fixed and the idle threads generally become more robust.
From: alexs <ashepard@u.washington.edu>
PPC build fix
From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
MIPS build fix
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use __do_IRQ instead. The only difference is that every controller
is now assumed to have an end() routine (only xics_8259 did not).
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
CPU freq support using 970FX powertune facility for iMac G5 and SMU
based single CPU desktop.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
