Currently pci-bridges are allocated enough resources to satisfy their immediate
requirements. Any additional resource-requests fail if additional free space,
contiguous to the one already allocated, is not available. This behavior is not
reasonable since sufficient contiguous resources, that can satisfy the request,
are available at a different location.
This patch provides the ability to expand and relocate a allocated resource.
v2: Changelog: Fixed size calculation in pci_reassign_resource()
v3: Changelog : Split this patch. The resource.c changes are already
upstream. All the pci driver changes are in here.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
decode_bar() and pci_calc_resource_flags() both looked at the PCI BAR
type information, and it's simpler to just do it all in one place.
decode_bar() sets IORESOURCE_IO, IORESOURCE_MEM, and IORESOURCE_MEM_64
as appropriate, so res->flags contains all the information pci_bar_type
does, so we don't need to test the pci_bar_type return value.
decode_bar() used to return pci_bar_type, which we no longer need. We
can simplify it a bit by returning the struct resource flags rather than
updating them internally.
In pci_update_resource(), there's no need to decode the BAR type bits
again; we can just test for IORESOURCE_MEM_64 directly.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
If we fail to assign resources to a PCI BAR, this patch makes us try the
original address from BIOS rather than leaving it disabled.
Linux tries to make sure all PCI device BARs are inside the upstream
PCI host bridge or P2P bridge apertures, reassigning BARs if necessary.
Windows does similar reassignment.
Before this patch, if we could not move a BAR into an aperture, we left
the resource unassigned, i.e., at address zero. Windows leaves such BARs
at the original BIOS addresses, and this patch makes Linux do the same.
This is a bit ugly because we disable the resource long before we try to
reassign it, so we have to keep track of the BIOS BAR address somewhere.
For lack of a better place, I put it in the struct pci_dev.
I think it would be cleaner to attempt the assignment immediately when the
claim fails, so we could easily remember the original address. But we
currently claim motherboard resources in the middle, after attempting to
claim PCI resources and before assigning new PCI resources, and changing
that is a fairly big job.
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=16263
Reported-by: Andrew <nitr0@seti.kr.ua>
Tested-by: Andrew <nitr0@seti.kr.ua>
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We can often deal with PCI resource issues by moving devices around. In
that case, there's no point in alarming the user with messages like these.
There are many bug reports where the message itself is the only problem,
e.g., https://bugs.launchpad.net/ubuntu/+source/linux/+bug/413419 .
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
With request_resource_conflict(), we can learn what the actual conflict is,
so print that info for debugging purposes.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This makes PCI resource management messages more consistent and adds a few
new messages to aid debugging.
Whenever we assign resources to a device, update a BAR, or change a
bridge aperture, it's worth noting it.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This
is the diff between v1 and v2.
The changes in this patch are:
- tidied vsprintf stack buffer to shrink and compute size more
accurately
- use %pR for decoding and %pr for "raw" (with type and flags) instead
of adding %pRt and %pRf
[1] http://lkml.org/lkml/2009/10/6/491
[2] http://lkml.org/lkml/2009/10/13/441
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Adrian commented out this function in 2baad5f96b, but I don't think
it's even worth cluttering the file with the unused code.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
yenta needs this for example.
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
An SR-IOV capable device includes an SR-IOV PCIe capability which
describes the Virtual Function (VF) BAR requirements. A typical SR-IOV
device can support multiple VFs whose BARs must be in a contiguous region,
effectively an array of VF BARs. The BAR reports the size requirement
for a single VF. We calculate the full range needed by simply multiplying
the VF BAR size with the number of possible VFs and create a resource
spanning the full range.
This all seems sane enough except it artificially inflates the alignment
requirement for the VF BAR. The VF BAR need only be aligned to the size
of a single BAR not the contiguous range of VF BARs. This can cause us
to fail to allocate resources for the BAR despite the fact that we
actually have enough space.
This patch adds a thin PCI specific layer over the generic
resource_alignment() function which is aware of the special nature of
VF BARs and does sorting and allocation based on the smaller alignment
requirement.
I recognize that while resource_alignment is generic, it's basically a
PCI helper. An alternative to this patch is to add PCI VF BAR specific
information to struct resource. I opted for the extra layer rather than
adding such PCI specific information to struct resource. This does
have the slight downside that we don't cache the BAR size and re-read
for each alignment query (happens a small handful of times during boot
for each VF BAR).
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Yu Zhao <yu.zhao@intel.com>
Cc: stable@kernel.org
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This function has traditionally used "insert_resource()", because before
commit cebd78a8c5 ("Fix pci_claim_resource") it used to just insert the
resource into whatever root resource tree that was indicated by
"pcibios_select_root()".
So there Matthew fixed it to actually look up the proper parent
resource, which means that now it's actively wrong to then traverse the
resource tree any more: we already know exactly where the new resource
should go.
And when we then did commit a76117dfd6 ("x86: Use pci_claim_resource"),
which changed the x86 PCI code from the open-coded
pr = pci_find_parent_resource(dev, r);
if (!pr || request_resource(pr, r) < 0) {
to using
if (pci_claim_resource(dev, idx) < 0) {
that "insert_resource()" now suddenly became a problem, and causes a
regression covered by
http://bugzilla.kernel.org/show_bug.cgi?id=13891
which this fixes.
Reported-and-tested-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Andrew Patterson <andrew.patterson@hp.com>
Cc: Linux PCI <linux-pci@vger.kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (74 commits)
PCI: make msi_free_irqs() to use msix_mask_irq() instead of open coded write
PCI: Fix the NIU MSI-X problem in a better way
PCI ASPM: remove get_root_port_link
PCI ASPM: cleanup pcie_aspm_sanity_check
PCI ASPM: remove has_switch field
PCI ASPM: cleanup calc_Lx_latency
PCI ASPM: cleanup pcie_aspm_get_cap_device
PCI ASPM: cleanup clkpm checks
PCI ASPM: cleanup __pcie_aspm_check_state_one
PCI ASPM: cleanup initialization
PCI ASPM: cleanup change input argument of aspm functions
PCI ASPM: cleanup misc in struct pcie_link_state
PCI ASPM: cleanup clkpm state in struct pcie_link_state
PCI ASPM: cleanup latency field in struct pcie_link_state
PCI ASPM: cleanup aspm state field in struct pcie_link_state
PCI ASPM: fix typo in struct pcie_link_state
PCI: drivers/pci/slot.c should depend on CONFIG_SYSFS
PCI: remove redundant __msi_set_enable()
PCI PM: consistently use type bool for wake enable variable
x86/ACPI: Correct maximum allowed _CRS returned resources and warn if exceeded
...
Instead of starting from the iomem or ioport roots, start from the
parent bus' resources. This fixes a bug where child resources would
appear above their parents resources if they had the same size.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Tested-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We could run out of space under under 4g, but devices under transparent
bridges can use 64bit resources, so keep trying on the parent bus until
we hit a non-transparent bridge.
Impact: better support for assigning unassigned resources
Reviewed-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch allows memory resources to be assigned with a specified
alignment at boot-time or run-time. The patch is useful when we use PCI
pass-through, because page-aligned memory resources are required to
securely share PCI resources with guest drivers.
If you want to assign the resource at boot time, please set
"pci=resource_alignment=" boot parameter.
This is format of "pci=resource_alignment=" boot parameter:
[<order of align>@][<domain>:]<bus>:<slot>.<func>[; ...]
Specifies alignment and device to reassign
aligned memory resources.
If <order of align> is not specified, PAGE_SIZE is
used as alignment.
PCI-PCI bridge can be specified, if resource
windows need to be expanded.
This is example:
pci=resource_alignment=20@07:00.0;18@0f:00.0;00:1d.7
If you want to assign the resource at run-time, please set
"/sys/bus/pci/resource_alignment" file, and hot-remove the device and
hot-add the device. For this purpose, fakephp or PCI hotplug interfaces
can be used.
The format of "/sys/bus/pci/resource_alignment" file is the same with
boot parameter. You can use "," instead of ";".
For example:
# cd /sys/bus/pci
# echo -n 20@12:00.0 > resource_alignment
# echo 1 > devices/0000:12:00.0/remove
# echo 1 > rescan
Reviewed-by: Alex Chiang <achiang@hp.com>
Reviewed-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Yuji Shimada <shimada-yxb@necst.nec.co.jp>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Add a function to map a given resource number to a corresponding
register so drivers can get the offset and type of device specific BARs.
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This cleanup removes unnecessary argument 'struct resource *res' in
pci_update_resource(), so it takes same arguments as other companion
functions (pci_assign_resource(), etc.).
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
These are easy to trigger (more or less harmlessly) with multiple video
cards, since the ROM BAR will typically not be given any space by the
BIOS bridge setup. No reason to punish quiet boot for this.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This is a cleanup that replaces the resource calculation formula with
resource_size().
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This converts things in drivers/pci to use %pR to printout the
content of a struct resource instead of hand-casted %llx or
other variants.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert printks to use dev_printk().
I converted pr_debug() to dev_dbg(). Both use KERN_DEBUG and are enabled
only when DEBUG is defined.
I converted printk(KERN_DEBUG) to dev_printk(KERN_DEBUG), not to dev_dbg(),
because dev_dbg() is only enabled when DEBUG is defined.
I converted DBG(KERN_INFO) (only in setup-bus.c) to dev_info(). The DBG()
name makes it sound like debug, but it's been enabled forever, so dev_info()
preserves the previous behavior.
I tried to make the resource assignment formats more consistent, e.g.,
"BAR %d: got res [%#llx-%#llx] bus [%#llx-%#llx] flags %#lx\n"
instead of sometimes using "start-end" and sometimes using "size@start".
I'm not attached to one or the other; I'd just like them consistent.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Done per Linus' request and suggestions. Linus has explained that
better than I'll be able to explain:
On Thu, Mar 27, 2008 at 10:12:10AM -0700, Linus Torvalds wrote:
> Actually, before we go any further, there might be a less intrusive
> alternative: add just a couple of flags to the resource flags field (we
> still have something like 8 unused bits on 32-bit), and use those to
> implement a generic "resource_alignment()" routine.
>
> Two flags would do it:
>
> - IORESOURCE_SIZEALIGN: size indicates alignment (regular PCI device
> resources)
>
> - IORESOURCE_STARTALIGN: start field is alignment (PCI bus resources
> during probing)
>
> and then the case of both flags zero (or both bits set) would actually be
> "invalid", and we would also clear the IORESOURCE_STARTALIGN flag when we
> actually allocate the resource (so that we don't use the "start" field as
> alignment incorrectly when it no longer indicates alignment).
>
> That wouldn't be totally generic, but it would have the nice property of
> automatically at least add sanity checking for that whole "res->start has
> the odd meaning of 'alignment' during probing" and remove the need for a
> new field, and it would allow us to have a generic "resource_alignment()"
> routine that just gets a resource pointer.
Besides, I removed IORESOURCE_BUS_HAS_VGA flag which was unused for ages.
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Each architecture has its own pcibios_enable_resources() implementation.
These differ in many minor ways that have nothing to do with actual
architectural differences. Follow-on patches will make most arches
use this generic version instead.
This version is based on powerpc, which seemed most up-to-date. The only
functional difference from the x86 version is that this uses "!r->parent"
to check for resource collisions instead of "!r->start && r->end".
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
An unused function that bloated the kernel only when CONFIG_EMBEDDED was
enabled...
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds appropriate casts to avoid a warning and print the correct
values in pr_debug.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Functions marked __devinit will be removed after kernel init. But being
exported they are potentially called by a module much later.
So the safer choice seems to be to keep the function even in the non
CONFIG_HOTPLUG case.
This silence the follwoing section mismatch warnings:
WARNING: drivers/built-in.o - Section mismatch: reference to .init.text:pci_bus_add_device from __ksymtab_gpl between '__ksymtab_pci_bus_add_device' (at offset 0x20) and '__ksymtab_pci_walk_bus'
WARNING: drivers/built-in.o - Section mismatch: reference to .init.text:pci_create_bus from __ksymtab_gpl between '__ksymtab_pci_create_bus' (at offset 0x40) and '__ksymtab_pci_stop_bus_device'
WARNING: drivers/built-in.o - Section mismatch: reference to .init.text:pci_bus_max_busnr from __ksymtab_gpl between '__ksymtab_pci_bus_max_busnr' (at offset 0xc0) and '__ksymtab_pci_assign_resource_fixed'
WARNING: drivers/built-in.o - Section mismatch: reference to .init.text:pci_claim_resource from __ksymtab_gpl between '__ksymtab_pci_claim_resource' (at offset 0xe0) and '__ksymtab_pcie_port_bus_type'
WARNING: drivers/built-in.o - Section mismatch: reference to .init.text:pci_bus_add_devices from __ksymtab between '__ksymtab_pci_bus_add_devices' (at offset 0x70) and '__ksymtab_pci_bus_alloc_resource'
WARNING: drivers/built-in.o - Section mismatch: reference to .init.text:pci_scan_bus_parented from __ksymtab between '__ksymtab_pci_scan_bus_parented' (at offset 0x90) and '__ksymtab_pci_root_buses'
WARNING: drivers/built-in.o - Section mismatch: reference to .init.text:pci_bus_assign_resources from __ksymtab between '__ksymtab_pci_bus_assign_resources' (at offset 0x4d0) and '__ksymtab_pci_bus_size_bridges'
WARNING: drivers/built-in.o - Section mismatch: reference to .init.text:pci_bus_size_bridges from __ksymtab between '__ksymtab_pci_bus_size_bridges' (at offset 0x4e0) and '__ksymtab_pci_setup_cardbus'
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Since commit 368c73d4f6 the kernel will try
to update the non-writeable BAR registers 0..3 of PIIX4 IDE adapters if
pci_assign_unassigned_resources() is used to do full resource assignment of
the bus. This fails because in the PIIX4 these BAR registers have
implicitly assumed values and read back as zero; it used to work because
the kernel used to just write zero to that register the read back value did
match what was written.
The fix is a new resource flag IORESOURCE_PCI_FIXED used to mark a resource
as non-movable. This will also be useful to keep other import system
resources from being moved around - for example system consoles on PCI
busses.
[akpm@osdl.org: cleanup]
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Based on a patch series originally from Vivek Goyal <vgoyal@in.ibm.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is needed if we wish to change the size of the resource structures.
Based on an original patch from Vivek Goyal <vgoyal@in.ibm.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
PCI: Add pci_assign_resource_fixed -- allow fixed address assignments
On some embedded systems the PCI address for hotplug devices are not only
known a priori but are required to be at a given PCI address for other
master in the system to be able to access.
An example of such a system would be an FPGA which is setup from user space
after the system has booted. The FPGA may be access by DSPs in the system
and those DSPs expect the FPGA at a fixed PCI address.
Added pci_assign_resource_fixed() as a way to allow assignment of the PCI
devices's BARs at fixed PCI addresses.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The RPAPHP hoplug driver will not build as a module, because it calls
on pci_claim_resource(), which is not exported. This exports the symbol.
Problem reported by Olaf Hering <olh@suse.de>
A grep indicates that building drivers/parisc/lba_pci.c
would have trouble building as a module for the same reason.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There were three changes necessary in order to allow
sparc64 to use setup-res.c:
1) Sparc64 roots the PCI I/O and MEM address space using
parent resources contained in the PCI controller structure.
I'm actually surprised no other platforms do this, especially
ones like Alpha and PPC{,64}. These resources get linked into the
iomem/ioport tree when PCI controllers are probed.
So the hierarchy looks like this:
iomem --|
PCI controller 1 MEM space --|
device 1
device 2
etc.
PCI controller 2 MEM space --|
...
ioport --|
PCI controller 1 IO space --|
...
PCI controller 2 IO space --|
...
You get the idea. The drivers/pci/setup-res.c code allocates
using plain iomem_space and ioport_space as the root, so that
wouldn't work with the above setup.
So I added a pcibios_select_root() that is used to handle this.
It uses the PCI controller struct's io_space and mem_space on
sparc64, and io{port,mem}_resource on every other platform to
keep current behavior.
2) quirk_io_region() is buggy. It takes in raw BUS view addresses
and tries to use them as a PCI resource.
pci_claim_resource() expects the resource to be fully formed when
it gets called. The sparc64 implementation would do the translation
but that's absolutely wrong, because if the same resource gets
released then re-claimed we'll adjust things twice.
So I fixed up quirk_io_region() to do the proper pcibios_bus_to_resource()
conversion before passing it on to pci_claim_resource().
3) I was mistakedly __init'ing the function methods the PCI controller
drivers provide on sparc64 to implement some parts of these
routines. This was, of course, easy to fix.
So we end up with the following, and that nasty SPARC64 makefile
ifdef in drivers/pci/Makefile is finally zapped.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some PCI devices (e.g. 3c905B, 3c556B) lose all configuration
(including BARs) when transitioning from D3hot->D0. This leaves such
a device in an inaccessible state. The patch below causes the BARs
to be restored when enabling such a device, so that its driver will
be able to access it.
The patch also adds pci_restore_bars as a new global symbol, and adds a
correpsonding EXPORT_SYMBOL_GPL for that.
Some firmware (e.g. Thinkpad T21) leaves devices in D3hot after a
(re)boot. Most drivers call pci_enable_device very early, so devices
left in D3hot that lose configuration during the D3hot->D0 transition
will be inaccessible to their drivers.
Drivers could be modified to account for this, but it would
be difficult to know which drivers need modification. This is
especially true since often many devices are covered by the same
driver. It likely would be necessary to replicate code across dozens
of drivers.
The patch below should trigger only when transitioning from D3hot->D0
(or at boot), and only for devices that have the "no soft reset" bit
cleared in the PM control register. I believe it is safe to include
this patch as part of the PCI infrastructure.
The cleanest implementation of pci_restore_bars was to call
pci_update_resource. Unfortunately, that does not currently exist
for the sparc64 architecture. The patch below includes a null
implemenation of pci_update_resource for sparc64.
Some have expressed interest in making general use of the the
pci_restore_bars function, so that has been exported to GPL licensed
modules.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Writing even a disabled value seems to mess up some matrox graphics
cards. It may be a card-related issue, but we may also be writing
reserved low bits in the result.
This was a fall-out of switching x86 over to the generic PCI resource
allocation code, and needs more debugging. In particular, the old x86
code defaulted to not doing any resource allocations at all for ROM
resources.
In the meantime, this has been reported to make X happier by Helge
Hafting <helgehaf@aitel.hist.no>.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Revert commit fec59a711e, which is
breaking sparc64 that doesn't have a working pci_update_resource.
We'll re-do this after 2.6.13 when we'll do it all properly.
For 64-bit BAR[i] only pci_dev->resource[i] is valid, ->resource[i+1]
slot is unused and contains zeroes in all fields.
So when we update a PCI BAR, all we need is just to check that we're
going to update a _valid_ resource.
Also make sure to write high bits - use "x >> 16 >> 16" (rather than the
simpler ">> 32") to avoid warnings on 32-bit architectures where we're
not going to have any high bits.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some PCI devices (e.g. 3c905B, 3c556B) lose all configuration
(including BARs) when transitioning from D3hot->D0. This leaves such
a device in an inaccessible state. The patch below causes the BARs
to be restored when enabling such a device, so that its driver will
be able to access it.
The patch also adds pci_restore_bars as a new global symbol, and adds a
correpsonding EXPORT_SYMBOL_GPL for that.
Some firmware (e.g. Thinkpad T21) leaves devices in D3hot after a
(re)boot. Most drivers call pci_enable_device very early, so devices
left in D3hot that lose configuration during the D3hot->D0 transition
will be inaccessible to their drivers.
Drivers could be modified to account for this, but it would
be difficult to know which drivers need modification. This is
especially true since often many devices are covered by the same
driver. It likely would be necessary to replicate code across dozens
of drivers.
The patch below should trigger only when transitioning from D3hot->D0
(or at boot), and only for devices that have the "no soft reset" bit
cleared in the PM control register. I believe it is safe to include
this patch as part of the PCI infrastructure.
The cleanest implementation of pci_restore_bars was to call
pci_update_resource. Unfortunately, that does not currently exist
for the sparc64 architecture. The patch below includes a null
implemenation of pci_update_resource for sparc64.
Some have expressed interest in making general use of the the
pci_restore_bars function, so that has been exported to GPL licensed
modules.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
