Commit Graph

76 Commits

Author SHA1 Message Date
Dan Williams 4fdadebc31 msi: fix ARM compile
In file included from drivers/pci/msi.c:22:
include/asm/smp.h:17:26: asm/arch/smp.h: No such file or directory
include/asm/smp.h:20:3: #error "<asm-arm/smp.h> included in non-SMP build"
include/asm/smp.h:23:1: warning: "raw_smp_processor_id" redefined
In file included from include/linux/sched.h:65,
                 from include/linux/mm.h:4,
                 from drivers/pci/msi.c:10:
include/linux/smp.h:85:1: warning: this is the location of the previous
definition

Tested on powerpc, i386, and x86_64.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-31 16:56:36 -07:00
David Miller b3b7cc7b41 Fix assertion failure with MSI on sparc64
Today's find is a triggered assertion in msi_free_irqs() when the system
doesn't support MSI, in which case arch_setup_msi_irqs() always returns
an error.

The problem is that when this happens we branch into msi_free_irqs(), to
which you added the following assertion loop:

	list_for_each_entry(entry, &dev->msi_list, list)
		BUG_ON(irq_has_action(entry->irq));

Well, if arch_setup_msi_irqs() fails, entry->irq will be zero and
although that's never assigned to any normal devices we use that IRQ
number for the timer interrupt on sparc64 so this assertion triggers.

Better to test for zero before doing the irq_has_action() assertion
thing.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 16:01:18 -07:00
Randy Dunlap e63340ae6b header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:07 -07:00
Michael Ellerman 032de8e2fe MSI: Give archs the option to free all MSI/Xs at once.
This patch introduces an optional function, arch_teardown_msi_irqs(),
which gives an arch the opportunity to do per-device teardown for
MSI/X. If that's not required, the default version simply calls
arch_teardown_msi_irq() for each msi irq required.

arch_teardown_msi_irqs() is simply passed a pdev, attached to the pdev
is a list of msi_descs, it is up to the arch to free the irq associated
with each of these as appropriate.

For archs that _don't_ implement arch_teardown_msi_irqs(), all msi_descs
with irq == 0 are considered unallocated, and the arch teardown routine
is not called on them.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:38 -07:00
Michael Ellerman 9c8313343c MSI: Give archs the option to allocate all MSI/Xs at once.
This patch introduces an optional function, arch_setup_msi_irqs(),
(note the plural) which gives an arch the opportunity to do per-device
setup for MSI/X and then allocate all the requested MSI/Xs at once.

If that's not required by the arch, the default version simply calls
arch_setup_msi_irq() for each MSI irq required.

arch_setup_msi_irqs() is passed a pdev, attached to the pdev is a list
of msi_descs with irq == 0, it is up to the arch to connect these up to
an irq (via set_irq_msi()) or return an error. For convenience the number
of vectors and the type are passed also.

All msi_descs with irq != 0 are considered allocated, and the arch
teardown routine will be called on them when necessary.

The existing semantics of pci_enable_msix() are that if the requested
number of irqs can not be allocated, the maximum number that _could_ be
allocated is returned. To support that, we define that in case of an
error from arch_setup_msi_irqs(), the number of msi_descs with irq != 0
are considered allocated, and are counted toward the "max that could be
allocated".


Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:38 -07:00
Michael Ellerman 7fe3730de7 MSI: arch must connect the irq and the msi_desc
set_irq_msi() currently connects an irq_desc to an msi_desc. The archs call
it at some point in their setup routine, and then the generic code sets up the
reverse mapping from the msi_desc back to the irq.

set_irq_msi() should do both connections, making it the one and only call
required to connect an irq with it's MSI desc and vice versa.

The arch code MUST call set_irq_msi(), and it must do so only once it's sure
it's not going to fail the irq allocation.

Given that there's no need for the arch to return the irq anymore, the return
value from the arch setup routine just becomes 0 for success and anything else
for failure.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:38 -07:00
Michael Ellerman 314e77b3ee MSI: Remove dev->first_msi_irq
Now that we keep a list of msi descriptors, we don't need first_msi_irq
in the pci dev.

If we somehow have zero MSIs configured list_entry() will give us weird
oopes or nice memory corruption bugs. So be paranoid. Add BUG_ONs and also
a check in pci_msi_check_device() to make sure nvec > 0.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:37 -07:00
Michael Ellerman 4aa9bc955d MSI: Use a list instead of the custom link structure
The msi descriptors are linked together with what looks a lot like
a linked list, but isn't a struct list_head list. Make it one.

The only complication is that previously we walked a list of irqs, and
got the descriptor for each with get_irq_msi(). Now we have a list of
descriptors and need to get the irq out of it, so it needs to be in the
actual struct msi_desc. We use 0 to indicate no irq is setup.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:37 -07:00
Michael Ellerman c9953a73e9 MSI: Add an arch_msi_check_device()
Add an arch_check_device(), which gives archs a chance to check the input
to pci_enable_msi/x. The arch might be interested in the value of nvec so
pass it in. Propagate the error value returned from the arch routine out
to the caller.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:37 -07:00
Michael Ellerman 17bbc12acd MSI: Rename pci_msi_supported() to pci_msi_check_device()
As pointed out by Eric, the name pci_msi_supported() suggests it should
return a boolean value, however it doesn't. So update the name to be
a bit less confusing and update the doco too.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman 128bc5fced MSI: Consolidate precondition checks
Consolidate precondition checks into a single if statement.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman b1e2303dba MSI: Expand pci_msi_supported()
pci_enable_msi() and pci_enable_msix() both search for the MSI/MSI-X
capability, we can fold this into pci_msi_supported() by passing the
type in.

Update the code to match the comment for pci_msi_supported(). That is
it returns 0 on success, and anything else indicates an error.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman 3e916c0503 MSI: Remove msi_cache
We don't need a special cache just for msi descriptors. They're not
particularly large, under 100 bytes for sure, and don't seem to require any
special alignment etc. On most systems there will be relatively few MSIs,
and hence we waste most of a page on the cache. Better to just kzalloc the
space for the few we do need.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman 4cc086fa5b MSI: Move EXPORT_SYMBOL()s near their definition
Move EXPORT_SYMBOL()s near their definition.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman 7ede9c1fa5 MSI: Consolidate BUG_ON()s.
When freeing MSIs and MSI-Xs, we BUG_ON() if the irq has not been
freed, ie. if it still has an action. We can consolidate all of these
BUG_ON()s into msi_free_irqs() as all the code paths lead there almost
immediately anyway.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman fc4afc7b2b MSI: Consolidate MSI-X irq freeing code
For the MSI-X case we do exactly the same logic in pci_disable_msix() and
msi_remove_pci_irq_vectors(), so consolidate them.

msi_remove_pci_irq_vectors() wasn't setting dev->first_msi_irq to 0, but
I think it should have been, so the consolidated version does.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman 00ba16ab26 MSI: Simplify BUG() handling in msi_remove_pci_irq_vectors() part 2
Although it might be nice to do a printk before BUG'ing, it's really not
necessary, and it complicates the code.

The behaviour has changed slightly, in that before we set a flag if the irq
had an action, and continued freeing the other irqs. But as I see it that's
all irrelevant because we end up BUG'ing anyway.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman c31af39870 MSI: Simplify BUG() handling in msi_remove_pci_irq_vectors() part 1
Although it might be nice to do a printk before BUG'ing, it's really not
necessary, and it complicates the code.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman 54bc6c0b0e MSI: Simplify BUG() handling in pci_disable_msix()
Although it might be nice to do a printk before BUG'ing, it's really not
necessary, and it complicates the code.

The behaviour has changed slightly, in that before we set a flag if the irq
had an action, and continued freeing the other irqs. But as I see it that's
all irrelevant because we end up BUG'ing anyway.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:36 -07:00
Michael Ellerman e387b9eefe MSI: Simplify BUG() handling in pci_disable_msi()
Although it might be nice to do a printk before BUG'ing, it's really not
necessary, and it complicates the code.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:35 -07:00
Mitch Williams 988cbb15e0 PCI: Flush MSI-X table writes
This patch fixes a kernel bug which is triggered when using the
irqbalance daemon with MSI-X hardware.

Because both MSI-X interrupt messages and MSI-X table writes are posted,
it's possible for them to cross while in-flight.  This results in
interrupts being received long after the kernel thinks they're disabled,
and in interrupts being sent to stale vectors after rebalancing.

This patch performs a read flush after writes to the MSI-X table for
mask and unmask operations.  Since the SMP affinity is set while
the interrupt is masked, and since it's unmasked immediately after,
no additional flushes are required in the various affinity setting
routines.

This patch has been validated with (unreleased) network hardware which
uses MSI-X.

Revised with input from Eric Biederman.

Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:34 -07:00
Eric W. Biederman 348e3fd194 [PATCH] msi: synchronously mask and unmask msi-x irqs.
This is a simplified and actually more comprehensive form of a bug
fix from Mitch Williams <mitch.a.williams@intel.com>.

When we mask or unmask a msi-x irqs the writes may be posted because
we are writing to memory mapped region.  This means the mask and
unmask don't happen immediately but at some unspecified time in the
future.  Which is out of sync with how the mask/unmask logic work
for ioapic irqs.

The practical result is that we get very subtle and hard to track down
irq migration bugs.

This patch performs a read flush after writes to the MSI-X table for mask
and unmask operations.  Since the SMP affinity is set while the interrupt
is masked, and since it's unmasked immediately after, no additional flushes
are required in the various affinity setting routines.

The testing by Mitch Williams on his especially problematic system should
still be valid as I have only simplified the code, not changed the
functionality.

We currently have 7 drivers: cciss, mthca, cxgb3, forceth, s2io,
pcie/portdrv_core, and qla2xxx in 2.6.21 that are affected by this
problem when the hardware they driver is plugged into the right slot.

Given the difficulty of reproducing this bug and tracing it down to
anything that even remotely resembles a cause, even if people are
being affected we aren't likely to see many meaningful bug reports, and
the people who see this bug aren't likely to be able to reproduce this
bug in a timely fashion.  So it is best to get this problem fixed
as soon as we can so people don't have problems.

Then if people do have a kernel message stating "No irq for vector" we
will know it is yet another novel cause that needs a complete new
investigation.

Cc: Greg KH <greg@kroah.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Mitch Williams <mitch.a.williams@intel.com>
Acked-by: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-03 14:02:49 -07:00
Eric W. Biederman 392ee1e6dd [PATCH] msi: Safer state caching.
There are two ways pci_save_state and pci_restore_state are used.  As
helper functions during suspend/resume, and as helper functions around
a hardware reset event.  When used as helper functions around a hardware
reset event there is no reason to believe the calls will be paired, nor
is there a good reason to believe that if we restore the msi state from
before the reset that it will match the current msi state.  Since arch
code may change the msi message without going through the driver, drivers
currently do not have enough information to even know when to call
pci_save_state to ensure they will have msi state in sync with the other
kernel irq reception data structures.

It turns out the solution is straight forward, cache the state in the
existing msi data structures (not the magic pci saved things) and
have the msi code update the cached state each time we write to the hardware.
This means we never need to read the hardware to figure out what the hardware
state should be.

By modifying the caching in this manner we get to remove our save_state
routines and only need to provide restore_state routines.

The only fields that were at all tricky to regenerate were the msi and msi-x
control registers and the way we regenerate them currently is a bit dependent
upon assumptions on how we use the allow msi registers to be configured and used
making the code a little bit brittle.  If we ever change what cases we allow
or how we configure the msi bits we can address the fragility then.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Auke Kok <auke-jan.h.kok@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-12 16:31:50 -07:00
Eric W. Biederman 58e0543e8f [PATCH] msi: support masking msi irqs without a mask bit
For devices that do not support msi-x we only support 1 interrupt.  Therefore
we can disable that one interrupt by disabling the msi capability itself.  If
we leave the intx interrupts disabled while we have the msi capability
disabled no interrupts should be delivered from that device.

Devices with just the minimal msi support (and thus hitting this code path)
include things like the intel e1000 nic, so it looks like is going to be a
fairly common case and thus important to get right.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-05 07:57:50 -08:00
Eric W. Biederman b1cbf4e4dd [PATCH] msi: fix up the msi enable/disable logic
enable/disable_msi_mode have several side effects which keeps them from being
generally useful.  So this patch replaces them with with two much more
targeted functions: msi_set_enable and msix_set_enable.

This patch makes pci_dev->msi_enabled and pci_dev->msix_enabled the definitive
way to test if linux has enabled the msi capability, and has the appropriate
msi data structures set up.

This patch ensures that while writing the msi messages in save/restore and
during device initialization we have the msi capability disabled so we don't
get into races.  The pci spec requires that we do not have the msi capability
enabled and the msi messages unmasked while we write the messages.  Completely
disabling the capability is overkill but it is easy :)

Care has been taken so we never have both a msi capability and intx enabled
simultaneously.  We haven't run into a problem yet but better safe then sorry.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-05 07:57:50 -08:00
Eric W. Biederman f5f2b13129 [PATCH] msi: sanely support hardware level msi disabling
In some cases when we are not using msi we need a way to ensure that the
hardware does not have an msi capability enabled.  Currently the code has been
calling disable_msi_mode to try and achieve that.  However disable_msi_mode
has several other side effects and is only available when msi support is
compiled in so it isn't really appropriate.

Instead this patch implements pci_msi_off which disables all msi and msix
capabilities unconditionally with no additional side effects.

pci_disable_device was redundantly clearing the bus master enable flag and
clearing the msi enable bit.  A device that is not allowed to perform bus
mastering operations cannot generate intx or msi interrupt messages as those
are essentially a special case of dma, and require bus mastering.  So the call
in pci_disable_device to disable msi capabilities was redundant.

quirk_pcie_pxh also called disable_msi_mode and is updated to use pci_msi_off.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-05 07:57:50 -08:00
Eric W. Biederman f7feaca77d msi: Make MSI useable more architectures
The arch hooks arch_setup_msi_irq and arch_teardown_msi_irq are now
responsible for allocating and freeing the linux irq in addition to
setting up the the linux irq to work with the interrupt.

arch_setup_msi_irq now takes a pci_device and a msi_desc and returns
an irq.

With this change in place this code should be useable by all platforms
except those that won't let the OS touch the hardware like ppc RTAS.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:08 -08:00
Eric W. Biederman 5b912c108c msi: Kill the msi_desc array.
We need to be able to get from an irq number to a struct msi_desc.
The msi_desc array in msi.c had several short comings the big one was
that it could not be used outside of msi.c.  Using irq_data in struct
irq_desc almost worked except on some architectures irq_data needs to
be used for something else.

So this patch adds a msi_desc pointer to irq_desc, adds the appropriate
wrappers and changes all of the msi code to use them.

The dynamic_irq_init/cleanup code was tweaked to ensure the new
field is left in a well defined state.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:08 -08:00
Eric W. Biederman 1c659d61cf msi: Remove attach_msi_entry.
The attach_msi_entry has been reduced to a single simple assignment,
so for simplicity remove the abstraction and directory perform the
assignment.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:08 -08:00
Eric W. Biederman 866a8c87c4 msi: Fix msi_remove_pci_irq_vectors.
Since msi_remove_pci_irq_vectors is designed to be called during
hotplug remove it is actively wrong to query the hardware and expect
meaningful results back.

To that end remove the pci_find_capability calls.  Testing
dev->msi_enabled and dev->msix_enabled gives us all of the information
we need.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:07 -08:00
Eric W. Biederman d40f540ce6 msi: Remove msi_lock.
With the removal of msi_lookup_irq all of the functions using msi_lock
operated on a single device and none of them could reasonably be
called on that device at the same time. 

Since what little synchronization that needs to happen needs to happen
outside of the msi functions, msi_lock could never be contended and as
such is useless and just complicates the code.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:07 -08:00
Eric W. Biederman ded86d8d37 msi: Kill msi_lookup_irq
The function msi_lookup_irq was horrible.  As a side effect of running
it changed dev->irq, and then the callers would need to change it
back.  In addition it does a global scan through all of the irqs,
which seems to be the sole justification of the msi_lock.

To remove the neede for msi_lookup_irq I added first_msi_irq to struct
pci_dev.  Then depending on the context I replaced msi_lookup_irq with
dev->first_msi_irq, dev->msi_enabled, or dev->msix_enabled.

msi_enabled and msix_enabled were already present in pci_dev for other
reasons.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:07 -08:00
Michael Ellerman 8fed4b6523 MSI: Combine pci_(save|restore)_msi/msix_state
The PCI save/restore code doesn't need to care about MSI vs MSI-X, all
it really wants is to say "save/restore all MSI(-X) info for this device".

This is borne out in the code, we call the MSI and MSI-X save routines
side by side, and similarly with the restore routines.

So combine the MSI/MSI-X routines into pci_save_msi_state() and
pci_restore_msi_state(). It is up to those routines to decide what state
needs to be saved.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:07 -08:00
Michael Ellerman 0fcfdabbdb MSI: Remove pci_scan_msi_device()
pci_scan_msi_device() doesn't do anything anymore, so remove it.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:07 -08:00
Michael Ellerman 88187dfa4d MSI: Replace pci_msi_quirk with calls to pci_no_msi()
I don't see any reason why we need pci_msi_quirk, quirk code can just
call pci_no_msi() instead.

Remove the check of pci_msi_quirk in msi_init(). This is safe as all
calls to msi_init() are protected by calls to pci_msi_supported(),
which checks pci_msi_enable, which is disabled by pci_no_msi().

The pci_disable_msi routines didn't check pci_msi_quirk, only
pci_msi_enable, but as far as I can see that was a bug not a feature.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:06 -08:00
Satoru Takeuchi c54c187907 PCI: cleanup MSI code
Cleanup MSI code as follows:

 - fix some types
 - fix strange local variable definition
 - delete unnecessary blank line
 - add comment to #endif which is far from corresponding #ifdef

Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:50:06 -08:00
Linus Torvalds 7f3af60e5a Merge branch 'intx' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6
* 'intx' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6:
  PCI MSI: always toggle legacy-INTx-enable bit upon MSI entry/exit
2006-12-07 15:04:20 -08:00
Jeff Garzik 1769b46a3e PCI MSI: always toggle legacy-INTx-enable bit upon MSI entry/exit
The current code (prior to this change) would disable the PCI INTx
legacy interrupt when enabling MSI... but only on PCI Express.  We
should do this for all MSI devices, for safety's sake.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-12-07 17:56:06 -05:00
Christoph Lameter e18b890bb0 [PATCH] slab: remove kmem_cache_t
Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:25 -08:00
Brice Goglin 0306ebfa3b PCI: Improve pci_msi_supported() comments
Improve pci_msi_supported() comments.

Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-18 11:36:11 -07:00
Eric W. Biederman 3b7d1921f4 [PATCH] msi: refactor and move the msi irq_chip into the arch code
It turns out msi_ops was simply not enough to abstract the architecture
specific details of msi.  So I have moved the resposibility of constructing
the struct irq_chip to the architectures, and have two architecture specific
functions arch_setup_msi_irq, and arch_teardown_msi_irq.

For simple architectures those functions can do all of the work.  For
architectures with platform dependencies they can call into the appropriate
platform code.

With this msi.c is finally free of assuming you have an apic, and this
actually takes less code.

The helpers for the architecture specific code are declared in the linux/msi.h
to keep them separate from the msi functions used by drivers in linux/pci.h

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:29 -07:00
Eric W. Biederman 277bc33bc2 [PATCH] msi: only use a single irq_chip for msi interrupts
The logic works like this.

Since we no longer track the state logic by hand in msi.c startup and shutdown
are no longer needed.

By updating msi_set_mask_bit to work on msi devices that do not implement a
mask bit we can always call the mask/unmask functions.

What we really have are mask and unmask so we use them to implement the .mask
and .unmask functions instead of .enable and .disable.

By switching to the handle_edge_irq handler we only need an ack function that
moves the irq if necessary.  Which removes the old end and ack functions and
their peculiar logic of sometimes disabling an irq.

This removes the reliance on pre genirq irq handling methods.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:29 -07:00
Eric W. Biederman 1f80025e62 [PATCH] msi: simplify msi sanity checks by adding with generic irq code
Currently msi.c is doing sanity checks that make certain before an irq is
destroyed it has no more users.

By adding irq_has_action I can perform the test is a generic way, instead of
relying on a msi specific data structure.

By performing the core check in dynamic_irq_cleanup I ensure every user of
dynamic irqs has a test present and we don't free resources that are in use.

In msi.c this allows me to kill the attrib.state member of msi_desc and all of
the assciated code to maintain it.

To keep from freeing data structures when irq cleanup code is called to soon
changing dyanamic_irq_cleanup is insufficient because there are msi specific
data structures that are also not safe to free.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:29 -07:00
Eric W. Biederman 1ce03373a7 [PATCH] genirq: msi: make the msi code irq based and not vector based
The msi currently allocates irqs backwards.  First it allocates a platform
dependent routing value for an interrupt the ``vector'' and then it figures
out from the vector which irq you are on.

For ia64 this is fine.  For x86 and x86_64 this is complete nonsense and makes
an enourmous mess of the irq handling code and prevents some pretty
significant cleanups in the code for handling large numbers of irqs.

This patch refactors msi.c to work in terms of irqs and create_irq/destroy_irq
for dynamically managing irqs.

Hopefully this is finally a version of msi.c that is useful on more than just
x86 derivatives.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:28 -07:00
Eric W. Biederman 92db6d10bc [PATCH] genirq: msi: simplify the msi irq limit policy
Currently we attempt to predict how many irqs we will be able to allocate with
msi using pci_vector_resources and some complicated accounting, and then we
only allow each device as many irqs as we think are available on average.

Only the s2io driver even takes advantage of this feature all other drivers
have a fixed number of irqs they need and bail if they can't get them.

pci_vector_resources is inaccurate if anyone ever frees an irq.  The whole
implmentation is racy.  The current irq limit policy does not appear to make
sense with current drivers.  So I have simplified things.  We can revisit this
we we need a more sophisticated policy.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:27 -07:00
Eric W. Biederman 38bc036130 [PATCH] genirq: msi: refactor the msi_ops
The current msi_ops are short sighted in a number of ways, this patch attempts
to fix the glaring deficiences.

- Report in msi_ops if a 64bit address is needed in the msi message, so we
  can fail 32bit only msi structures.

- Send and receive a full struct msi_msg in both setup and target.  This is
  a little cleaner and allows for architectures that need to modify the data
  to retarget the msi interrupt to a different cpu.

- In target pass in the full cpu mask instead of just the first cpu in case
  we can make use of the full cpu mask.

- Operate in terms of irqs and not vectors, currently there is still a 1-1
  relationship but on architectures other than ia64 I expect this will change.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:27 -07:00
Eric W. Biederman 0366f8f713 [PATCH] genirq: msi: implement helper functions read_msi_msg and write_msi_msg
In support of this I also add a struct msi_msg that captures the the two
address and one data field ina typical msi message, and I remember the pos and
if the address is 64bit in struct msi_desc.

This makes the code a little more readable and easier to maintain, and paves
the way to further simplfications.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:27 -07:00
Eric W. Biederman 7bd007e480 [PATCH] genirq: msi: simplify msi enable and disable
The problem.  Because the disable routines leave the msi interrupts in all
sorts of half enabled states the enable routines become impossible to
implement correctly, and almost impossible to understand.

Simplifing this allows me to simply kill the buggy reroute_msix_table, and
generally makes the code more maintainable.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:26 -07:00
Pekka J Enberg 571817849c [PATCH] msi: use kmem_cache_zalloc()
Simpler, cleaner.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:19 -07:00
Brice Goglin 24334a1253 MSI: Factorize common code in pci_msi_supported()
pci_enable_msi() and pci_enable_msix() use the same code to detect
whether MSI might be enabled on this device. Factorize this code in
pci_msi_supported(). And improve the documentation about the fact
that only the root chipset must support MSI, but it is hard to
find the root bus so we check all parent busses MSI flags.

Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-26 17:43:52 -07:00