Based on an original patch from Arnd Bergmann
<arnd.bergmann@de.ibm.com>

If there's no entry in the mailbox, then a read on the _info file will
return data from an uninitialised variable.

This change returns EOF if there's no mailbox info available instead.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This fixes the behavior of spufs when a spu tries a DMA operation
based on a wrong / unavailable address.

Instead of just generating a SIGBUS signal, spufs now
generates a SIGSEGV signal and restarts the problematic DMA operation
after the execution of the application's signal handler.  This allows
applications to employ user-level paging systems.

Although the restart_dma function is called before the application's
signal handler, the operation is not actually performed at this time,
since the spu context is already stopped.  The operation only takes
place when spu_run is restarted (which happens automatically).
Signed-off-by: NAndre Detsch <adetsch@br.ibm.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The original spusched_timer was designed to take effect only when
a context is waiting in the runqueue.

This change adds an additional lower-freq timer has been added to
purely handle the spu_load updates. The new timer will be triggered
per LOAD_FREQ ticks.
Signed-off-by: NAegis Lin <aegislin@gmail.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Make most places that use spu_acquire/spu_acquire_saved interruptible,
this allows getting out of the spufs code when e.g. pressing ctrl+c.
There are a few places where we get called e.g. from spufs teardown
routines were we can't simply err out so these are left with a comment.
For now I've also not touched the poll routines because it's open what
libspe would expect in terms of interrupted system calls.
Acked-by: NArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The simple attr macros currently used by spufs can't deal with the
handlers returning errors, which is required to make the state_mutex
interruptible.  This adds a local copy that allows for an error
return from the get/set handlers.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Change spufs_spu_run so that the context is queued directly to the
scheduler and the controlling thread advances directly to spufs_wait()
for spe errors and exceptions.

nosched contexts are treated the same as before.

Fixes from Christoph Hellwig <hch@lst.de>
Signed-off-by: NLuke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This changes the spu context switch code to not write to reserved bits
of spu interrupt status register.
The architecture book says the reserved fields should be set to zero.
Signed-off-by: NMasato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Need to re-check priority after dropping lock.  Otherwise, a
more favored context may be preempted.
Signed-off-by: NLuke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This cleans up spu_run_init so that it does all of the spu
initialization for spufs_run_spu.  It initializes the spu context as
much as possible before it activates the spu and writes the runcntl
register.
Signed-off-by: NLuke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Based on original patches from
 Arnd Bergmann <arnd.bergman@de.ibm.com>; and
 Luke Browning <lukebr@linux.vnet.ibm.com>

Currently, spu contexts need to be loaded to the SPU in order to take
class 0 and class 1 exceptions.

This change makes the actual interrupt-handlers much simpler (ie,
set the exception information in the context save area), and defers the
handling code to the spufs_handle_class[01] functions, called from
spufs_run_spu.

This should improve the concurrency of the spu scheduling leading to
greater SPU utilization when SPUs are overcommited.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Add a few #defines for the class 0, 1 and 2 interrupt status bits, and
use them instead of magic numbers when we're setting or checking for
these interrupts.

Also, add a #define for the class 2 mailbox threshold interrupt mask.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

When doing a poll on the mbox stat file of a swapped-out context, we
clear the class 0 interrupt status, rather than the class 2 interrupt
status.

This change corrects the poll operation to clear the correct interrupt.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This change encapsulates the spu_privcntl_RW register so that it can
be written through backing ops.  This is necessary so that spu contexts
can be initialized and queued to the scheduler in spufs_run_spu.
Signed-off-by: NLuke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This change disables the logic that faults-in spu contexts under the
covers from the page fault handler.  When a fault requires a runnable
context, the handler will block until the context is scheduled by
other means.
Signed-off-by: NArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Currently, part of the spufs code (switch.o, lscsa_alloc.o and fault.o)
is compiled directly into the kernel.

This change moves these components of spufs into the kernel.

The lscsa and switch objects are fairly straightforward to move in.

For the fault.o module, we split the fault-handling code into two
parts: a/p/p/c/spu_fault.c and a/p/p/c/spufs/fault.c. The former is for
the in-kernel spu_handle_mm_fault function, and we move the rest of the
fault-handling code into spufs.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Fix a few typos in the spufs scheduler comments
Signed-off-by: NJulio M. Merino Vidal <jmerino@ac.upc.edu>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Add platform specific SPU run control routines to the spufs.  The current
spufs implementation uses the SPU master run control bit (MFC_SR1[S]) to
control SPE execution, but the PS3 hypervisor does not support the use of
this feature.

This change adds the run control wrapper routies spu_enable_spu() and
spu_disable_spu().  The bare metal routines use the master run control
bit, and the PS3 specific routines use the priv2 run control register.

An outstanding enhancement for the PS3 would be to add a guard to check
for incorrect access to the spu problem state when the spu context is
disabled.  This check could be implemented with a flag added to the spu
context that would inhibit mapping problem state pages, and a routine
to unmap spu problem state pages.  When the spu is enabled with
ps3_enable_spu() the flag would be set allowing pages to be mapped,
and when the spu is disabled with ps3_disable_spu() the flag would be
cleared and mapped problem state pages would be unmapped.
Signed-off-by: NMasato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: NGeoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

When a module has relocation sections with tens of thousands of
entries, counting the distinct/unique entries only (i.e. no
duplicates) at load time can take tens of seconds and up to minutes.
The sore point is the count_relocs() function which is called as part
of the architecture specific module loading processing path:

	-> load_module()			generic
	   -> module_frob_arch_sections()	arch specific
	      -> get_plt_size()		32-bit
	      -> get_stubs_size()	64-bit
		 -> count_relocs()

Here count_relocs is being called to find out how many distinct
targets of R_PPC_REL24 relocations there are, since each distinct
target needs a PLT entry or a stub created for it.

The previous counting algorithm has O(n^2) complexity.  Basically two
solutions were proposed on the e-mail list: a hash based approach and
a sort based approach.

The hash based approach is the fastest (O(n)) but the has it needs
additional memory and for certain corner cases it could take lots of
memory due to the degeneration of the hash.  One such proposal was
submitted here:

http://ozlabs.org/pipermail/linuxppc-dev/2007-June/037641.html

The sort based approach is slower (O(n * log n + n)) but if the
sorting is done "in place" it doesn't need additional memory.
This has O(n + n * log n) complexity with no additional memory
requirements.

This commit implements the in-place sort option.
Signed-off-by: NEmil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

There should be an of_node_put when breaking out of a loop that iterates
using for_each_node_by_type.

This was detected and fixed using the following semantic patch.
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
identifier d;
type T;
expression e;
iterator for_each_node_by_type;
@@

T *d;
...
for_each_node_by_type(d,...)
  {... when != of_node_put(d)
       when != e = d
(
   return d;
|
+  of_node_put(d);
?  return ...;
)
...}
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Cc: Christian Krafft <krafft@de.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Erb <djerb@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

There should be an of_node_put when breaking out of a loop that iterates
over calls to of_find_all_nodes, as this function does an of_node_get on
the value it returns.

This was fixed using the following semantic patch.
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
type T;
identifier d;
expression e;
@@

T *d;
...
for (d = NULL; (d = of_find_all_nodes(d)) != NULL; )
 {... when != of_node_put(d)
      when != e = d
(
   return d;
|
+  of_node_put(d);
?  return ...;
)
...}
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Remove an unnecessary pci_dev_put.  pci_dev_put is called implicitly
by the subsequent call to pci_get_device.

The problem was detected using the following semantic patch, and
corrected by hand.

@@
expression dev;
expression E;
@@

- pci_dev_put(dev)
   ... when != dev = E
- pci_get_device(...,dev)
Signed-off-by: NJulia Lawall <julia@diku.dk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Signed-off-by: NLucas Woods <woodzy@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Signed-off-by: NLucas Woods <woodzy@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The casting is safe only when the list_head member is the first member
of the structure, and even then it is better to use the address of the
list_head structure member.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This fixes a possible NULL pointer dereference inside of strncmp() if
of_get_property() fails.
Signed-off-by: NCyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

We were using -mno-minimal-toc on everything in arch/powerpc/kernel,
which means that all the functions in there were putting all their
TOC entries in the top-level TOC, and it was overflowing on an
allyesconfig build.  For various reasons, prom_init.c does need
-mno-minimal-toc, but the other .c files in there can use sub-TOCs
quite happily.  This change is sufficient for now to stop the TOC
overflowing; other directories under arch/powerpc also use
-mno-minimal-toc and could also be changed later if necessary.

Lmbench runs with and without this patch showed no significant speed
differences.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The PCI IRQ code has a fallback when the device-tree parsing fails, that
tries to map the interrupt indicated by PCI_INTERRUPT_LINE if the firmware
set something in there. This is a bit fragile but has proven useful in some
cases so far. However, it's causing us to incorrectly try to map interrupt 0
on various setups, so let's prevent that case, as none of the cases where
the fallback is legit should have an IRQ 0.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This patch changes the PowerPC PCI code to disable IO and/or Memory
decoding on a PCI device when a resource of that type failed to be
allocated.  This is done to avoid having unallocated dangling BARs
enabled that might try to decode on top of other devices.

If a proper resource is assigned later on, then pci_enable_device()
will take care of re-enabling decoding.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Apple firmware has a strange way to "close" bridge resources by setting
them to some bogus values that overlap RAM (strangely, I haven't seen it
conflicting with DMA so far...).  This explicitely closes them to avoid
problems.  Previously, they would be closed as a consequence of failing
to be allocated, but this makes it more explicit, and thus the log
message is more explicit too.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The device node for the HT bridge on G5s doesn't contain useful ranges.

We used to give it a bunch of the known PCI space and then punch a "hole"
in it based on where the AGP or PCIe region was.  This reworks it to
use the actual register in the bridge that controls the decoding instead.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This enables the PCI code to see the device that represents the
HT host bridge on the PowerMac G5.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Our implementation of pcibios_enable_device() has a couple of problems.

One is that it should not check IORESOURCE_UNSET, as this might be
left dangling after resource assignment (shouldn't but there are
bugs), but instead, we make it check resource->parent which should
be a reliable indication that the resource has been successfully
claimed (it's in the resource tree).

Then, we also need to skip ROM resources that haven't been enabled
as x86 does.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

It should now be safe to re-assign unassigned resources on 64 bits PowerMac
machines (G5s).  This clears pci_probe_only on those.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Powermac's use of the pcibios_enable_device_hook() got slightly
broken by the recent PCI merge in that it won't be called for
the "initial" case of assigning resources to a previously
unassigned device.  This was an abuse of that hook anyway, so
instead we now use a header quirk.

While at it, we move a #ifdef CONFIG_PPC32 to enclose more code
that is only ever used on 32 bits.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This merge the two implementations, based on the previously
fixed up 32 bits one.  The pcibios_enable_device_hook in ppc_md
is now available for ppc64 use.  Also remove the new unused
"initial" parameter from it and fixup users.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Our implementation of pcibios_enable_device() incorrectly ignores
the mask argument and always checks that all resources have been
allocated, which isn't the right thing to do anymore.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The way iSeries manages PCI IO and Memory resources is a bit strange
and is based on overriding the content of those resources with home
cooked ones afterward.

This changes it a bit to better integrate with the new resource handling
so that the "virtual" tokens that iSeries replaces resources with are
done from the proper per-device fixup hook, and bridge resources are
set to enclose that token space.  This fixes various things such as
the output of /proc/iomem & ioports, among others.  This also fixes up
various boot messages as well.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The 32 bits PCI code now uses the generic code for assigning unassigned
resources and an algorithm similar to x86 for claiming existing ones.

This works far better than the 64 bits code which basically can only
claim existing ones (pci_probe_only=1) or would fall apart completely.

This merges them so that the new 32 bits implementation is used for both.

64 bits now gets the new PCI flags for controlling the behaviour, though
the old pci_probe_only global is still there for now to be cleared if you
want to.

I kept a pcibios_claim_one_bus() function mostly based on the old 64
bits code for use by the DLPAR hotplug. This will have to be cleaned
up, thought I hope it will work in the meantime.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The PCI code in 32 and 64 bits fixes up resources differently.

32 bits uses a header quirk plus handles bridges in pcibios_fixup_bus()
while 64 bits does things in various places depending on whether you
are using OF probing, using PCI hotplug, etc...

This merges those by basically using the 32 bits approach for both,
with various tweaks to make 64 bits work with the new approach.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This merges the PowerPC 32 and 64 bits version of pcibios_resource_to_bus
and pcibios_bus_to_resource().
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>