linux-toradex.git/drivers/gpu/vga/vgaarb.c, branch v3.12-rc3

vgaarb: Fix VGA decodes changes

2013-09-03T17:17:59+00:00

When VGA decodes change we need to do a bit more evaluation of exactly what
has changed.  We don't necessarily give up all the old owns resources and
we need to account for resources with locks.  The new algorithm is: If
something is added, update decodes.  If legacy resources were added and
none were there before, we have a new participant.  If something is
removed, update decodes.  If we previously owned it, we no longer own it.
If it was previously locked, invalidate all locks and release it.  If
legacy resources were removed and none are left, remove the participant
from VGA arbitration.

Previously we updated decodes, released ownership of everything that was
previously decoded, ignored all locks, and went off looking for another
device to transfer VGA to.  In a test case where Intel IGD removes only
legacy VGA memory decoding, this left the arbiter switching to discrete
graphics without actually disabling legacy VGA IO from the IGD.  As a
bonus, we bumped up the count of VGA arbitration participants for no
good reason.

Signed-off-by: Alex Williamson 
Cc: Dave Airlie 
Acked-by: Dave Airlie 
Reviewed-by: Ville Syrjälä 
[danvet: Kill now unused variables, reported by the 0-day kernel
builtbot.]
Signed-off-by: Daniel Vetter

vgaarb: Don't disable resources that are not owned

2013-09-03T17:17:58+00:00

If a device does not own a resource then we don't need to disable it.
This resolves the case where an Intel IGD device can be configured to
disable decode of VGA memory but we still need the arbiter to handle
VGA I/O port routing.  When the IGD device is in conflict, only
PCI_COMMAND_IO should be disabled since VGA memory does not require
arbitration on this device.

Signed-off-by: Alex Williamson 
Cc: Dave Airlie 
Acked-by: Dave Airlie 
Reviewed-by: Ville Syrjälä 
Signed-off-by: Daniel Vetter

Merge branch 'pci/yinghai-misc' into next

2012-09-24T23:24:11+00:00

PCI: Fix default vga ref_count

2012-09-24T19:35:00+00:00

when __ARCH_HAS_VGA_DEFAULT_DEVICE is not defined, aka EFIFB is not used,
for static path, vga_default setting is through vga_arbiter_add_pci_device.
and later x86 pci_fixup_video, will skip setting again.
- subsys_initcall(vga_arb_device_init) come first to call
vga_arbiter_add_pci_device. It will call pci_get_dev to hold one reference.

for hotplug add path, even vga_arbiter_add_pci_device is called via
notifier, but it will check VGA_RSRC_LEGACY_MASK that is not set for
hotplug path.  So x86 pci_fixup_video will take over to call
vga_set_default_device().  It will not hold one refrence.

Later for hotplug remove path, vga_arbiter_del_pci_device that does not
check VGA_RSRC_LEGACY_MASK will call put_device and it will cause ref_count
to decrease extra. that will have that pci device get deleted early
wrongly.

Need to make get/put balance for both cases.

Signed-off-by: Yinghai Lu 
Signed-off-by: Bjorn Helgaas 
Cc: x86@kernel.org
Cc: Dave Airlie 
Cc: Andrew Morton 
Cc: Julia Lawall 
Cc: Matthew Garrett

PCI/vga: Use hotplug-safe pci_get_domain_bus_and_slot()

2012-09-12T20:13:11+00:00

Following code has a race window between pci_find_bus() and pci_get_slot()
if PCI hotplug operation happens between them which removes the pci_bus.
So use PCI hotplug safe interface pci_get_domain_bus_and_slot() instead,
which also reduces code complexity.

    struct pci_bus *pci_bus = pci_find_bus(domain, busno);
    struct pci_dev *pci_dev = pci_get_slot(pci_bus, devfn);

Signed-off-by: Jiang Liu 
Signed-off-by: Bjorn Helgaas

vga: fix build when fbdev is a module

2012-04-24T08:50:21+00:00

This fixes the build breakage reported by Stephen in -next
when merging the drm-next tree.

Signed-off-by: Dave Airlie

vgaarb: Add support for setting the default video device (v2)

2012-04-24T08:50:15+00:00

The default VGA device is a somewhat fluid concept on platforms with
multiple GPUs. Add support for setting it so switching code can update
things appropriately, and make sure that the sysfs code returns the right
device if it's changed.

v2: Updated to fix builds when __ARCH_HAS_VGA_DEFAULT_DEVICE is false.

Signed-off-by: Matthew Garrett 
Acked-by: H. Peter Anvin 
Acked-by: benh@kernel.crashing.org
Cc: airlied@redhat.com
Signed-off-by: Dave Airlie

drivers/gpu/vga/vgaarb.c: add missing kfree

2011-11-22T20:21:10+00:00

kbuf is a buffer that is local to this function, so all of the error paths
leaving the function should release it.

Signed-off-by: Julia Lawall 
Cc: Jesper Juhl 
Signed-off-by: Andrew Morton 
Signed-off-by: Dave Airlie

vgaarb: a NULL bridge is acceptable for root devices.

2011-11-14T10:03:15+00:00

I assumed all PCI buses had a bridge, but playing with qemu recently, I
discovered vgaarb bug where it wasn't detecting both devices shared a bridge
at the root level.

Don't check for NULL, if two buses have a NULL bridge, assume they share the
root bus.

Acked-by: Jesse Barnes 
Signed-off-by: Dave Airlie

drivers: use kzalloc/kcalloc instead of 'kmalloc+memset', where possible

2011-07-26T03:57:13+00:00

Signed-off-by: Rakib Mullick 
Cc: Jeff Garzik 
Cc: David Airlie 
Cc: Tejun Heo 
Cc: Joe Perches 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds