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  1. 05 Oct, 2006 27 commits
  3. 04 Oct, 2006 13 commits
    • Arnd Bergmann's avatar
      [POWERPC] cell: fix bugs found by sparse · 43b4f406
      Arnd Bergmann authored 
      - Some long constants should be marked 'ul'.
- When using desc->handler_data to pass an __iomem
  register area, we need to add casts to and from
  __iomem.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      43b4f406
    • Arnd Bergmann's avatar
      [POWERPC] spiderpic: enable new style devtree support · f7e2ce78
      Arnd Bergmann authored 
      This enables support for new firmware test releases.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      f7e2ce78
    • Arnd Bergmann's avatar
      [POWERPC] Update cell_defconfig · 68272047
      Arnd Bergmann authored 
      This adds defaults for new configuration options added since
2.6.18 and it enables the option for 64kb pages by default.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      68272047
    • Arnd Bergmann's avatar
      [POWERPC] spufs: add infrastructure for finding elf objects · 86767277
      Arnd Bergmann authored 
      This adds an 'object-id' file that the spe library can
use to store a pointer to its ELF object. This was
originally meant for use by oprofile, but is now
also used by the GNU debugger, if available.

In order for oprofile to find the location in an spu-elf
binary where an event counter triggered, we need a way
to identify the binary in the first place.

Unfortunately, that binary itself can be embedded in a
powerpc ELF binary. Since we can assume it is mapped into
the effective address space of the running process,
have that one write the pointer value into a new spufs
file.

When a context switch occurs, pass the user value to
the profiler so that can look at the mapped file (with
some care).
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      86767277
    • Arnd Bergmann's avatar
      [POWERPC] spufs: support new OF device tree format · 7650f2f2
      Arnd Bergmann authored 
      The properties we used traditionally in the device tree are somewhat
nonstandard.  This adds support for a more conventional format using
'interrupts' and 'reg' properties.

The interrupts are specified in three cells (class 0, 1 and 2) and
registered at the interrupt-parent.

The reg property contains either three or four register areas in the
order 'local-store', 'problem', 'priv2', and 'priv1', so the priv1 one
can be left out in case of hypervisor driven systems that access these
through hcalls.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      7650f2f2
    • Arnd Bergmann's avatar
      [POWERPC] spufs: add support for read/write on cntl · e1dbff2b
      Arnd Bergmann authored 
      Writing to cntl can be used to stop execution on the
spu and to restart it, reading from cntl gives the
contents of the current status register.

The access is always in ascii, as for most other files.

This was always meant to be there, but we had a little
problem with writing to runctl so it was left out so
far.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      e1dbff2b
    • Arnd Bergmann's avatar
      [POWERPC] spufs: remove support for ancient firmware · 772920e5
      Arnd Bergmann authored 
      Any firmware that still uses the 'spc' nodes already
stopped running for other reasons, so let's get rid of this.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      772920e5
    • Arnd Bergmann's avatar
      [POWERPC] spufs: make mailbox functions handle multiple elements · cdcc89bb
      Arnd Bergmann authored 
      Since libspe2 will provide a function that can read/write
multiple mailbox elements at once, the kernel should handle
that efficiently.

read/write on the three mailbox files can now access the
spe context multiple times to operate on any number of
mailbox data elements.

If the spu application keeps writing to its outbound
mailbox, the read call will pick up all the data in a
single system call.

Unfortunately, if the user passes an invalid pointer,
we may lose a mailbox element on read, since we can't
put it back. This probably impossible to solve, if the
user also accesses the mailbox through direct register
access.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      cdcc89bb
    • Arnd Bergmann's avatar
      [POWERPC] spufs: use correct pg_prot for mapping SPU local store · ac91cb8d
      Arnd Bergmann authored 
      This hopefully fixes a long-standing bug in the spu file system.
An spu context comes with local memory that can be either saved
in kernel pages or point directly to a physical SPE.

When mapping the physical SPE, that mapping needs to be cache-inhibited.
For simplicity, we used to map the kernel backing memory that way
too, but unfortunately that was not only inefficient, but also incorrect
because the same page could then be accessed simultaneously through
a cacheable and a cache-inhibited mapping, which is not allowed
by the powerpc specification and in our case caused data inconsistency
for which we did a really ugly workaround in user space.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      ac91cb8d
    • Arnd Bergmann's avatar
      [POWERPC] spufs: Add infrastructure needed for gang scheduling · 6263203e
      Arnd Bergmann authored 
      Add the concept of a gang to spufs as a new type of object.
So far, this has no impact whatsover on scheduling, but makes
it possible to add that later.

A new type of object in spufs is now a spu_gang. It is created
with the spu_create system call with the flags argument set
to SPU_CREATE_GANG (0x2). Inside of a spu_gang, it
is then possible to create spu_context objects, which until
now was only possible at the root of spufs.

There is a new member in struct spu_context pointing to
the spu_gang it belongs to, if any. The spu_gang maintains
a list of spu_context structures that are its children.
This information can then be used in the scheduler in the
future.

There is still a bug that needs to be resolved in this
basic infrastructure regarding the order in which objects
are removed. When the spu_gang file descriptor is closed
before the spu_context descriptors, we leak the dentry
and inode for the gang. Any ideas how to cleanly solve
this are appreciated.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      6263203e
    • Arnd Bergmann's avatar
      [POWERPC] spufs: implement error event delivery to user space · 9add11da
      Arnd Bergmann authored 
      This tries to fix spufs so we have an interface closer to what is
specified in the man page for events returned in the third argument of
spu_run.

Fortunately, libspe has never been using the returned contents of that
register, as they were the same as the return code of spu_run (duh!).

Unlike the specification that we never implemented correctly, we now
require a SPU_CREATE_EVENTS_ENABLED flag passed to spu_create, in
order to get the new behavior. When this flag is not passed, spu_run
will simply ignore the third argument now.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      9add11da
    • HyeonSeung Jang's avatar
      [POWERPC] spufs: fix context switch during page fault · 28347bce
      HyeonSeung Jang authored 
      For better explanation, I break down the page fault handling into steps:

1) There is a page fault caused by DMA operation initiated by SPU and
DMA is suspended.

2) The interrupt handler 'spu_irq_class_1()/__spu_trap_data_map()' is
called and it just wakes up the sleeping spe-manager thread.

3) by PPE scheduler, the corresponding bottom half,
spu_irq_class_1_bottom() is called in process context and DMA is
restarted.

There can be a quite large time gap between 2) and 3) and I found
the following problem:

Between 2) and 3) If the context becomes unbound, 3) is not executed
because when the spe-manager thread is awaken, the context is already
saved. (This situation can happen, for example, when a high priority spe
thread newly started in that time gap)

But the actual problem is that the corresponding SPU context does not
work even if it is bound again to a SPU.

Besides I can see the following warning in mambo simulator when the
context becomes
unbound(in save_mfc_cmd()), i.e. when unbind() is called for the
context after step 2) before 3) :

'WARNING: 61392752237: SPE2: MFC_CMD_QUEUE channel count of 15 is
inconsistent with number of available DMA queue entries of 16'

After I go through available documents, I found that the problem is
because the suspended DMA is not restarted when it is bound again.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      28347bce
    • Mark Nutter's avatar
      [POWERPC] spufs: scheduler support for NUMA. · a68cf983
      Mark Nutter authored 
      This patch adds NUMA support to the the spufs scheduler.

The new arch/powerpc/platforms/cell/spufs/sched.c is greatly
simplified, in an attempt to reduce complexity while adding
support for NUMA scheduler domains.  SPUs are allocated starting
from the calling thread's node, moving to others as supported by
current->cpus_allowed.  Preemption is gone as it was buggy, but
should be re-enabled in another patch when stable.

The new arch/powerpc/platforms/cell/spu_base.c maintains idle
lists on a per-node basis, and allows caller to specify which
node(s) an SPU should be allocated from, while passing -1 tells
spu_alloc() that any node is allowed.

Since the patch removes the currently implemented preemptive
scheduling, it is technically a regression, but practically
all users have since migrated to this version, as it is
part of the IBM SDK and the yellowdog distribution, so there
is not much point holding it back while the new preemptive
scheduling patch gets delayed further.
Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      a68cf983