updating the GTT and flushing the AGP TLB by storing the GTT in
write-combining memory.
On x86 flushing the AGP TLB is done by an I/O operation or a store to a
MMIO register in uncacheable memory. Both cases imply that WC buffers are
flushed so no memory barriers are needed.
On powerpc there is no WC memory type. It maps to uncacheable memory and
two stores to uncacheable memory, such as to the GTT and then to an MMIO
register, are strongly ordered, so no memory barriers are needed either.
MFC after: 1 month
operations required by GEMified i915.ko. It also attaches to SandyBridge
and IvyBridge CPU northbridges now.
Sponsored by: The FreeBSD Foundation
MFC after: 1 month
bumped to 800004 to note the change though userland apps should not be
affected since they use <sys/agpio.h> rather than the headers in
sys/dev/agp.
Discussed with: anholt
Repocopy by: simon
/dev/agpgart and agp_free_res() frees resources like the BAR for the
aperture. Splitting this up lets chipset-specific detach routines
manipulate the aperture during their detach routines without panicing.
MFC after: 1 week
Reviewed by: anholt
This adds a function to agp.c to set the aperture resource ID if it's
not the usual AGP_APBASE. Previously, agp.c had been assuming
AGP_APBASE, which resulted in incorrect agp_info, and contortions by
agp_i810.c to work around it.
This also adds functions to agp.c for default AGP_GET_APERTURE() and
AGP_SET_APERTURE(), which return the aperture resource size and disallow
aperture size changes. Moving to these for our AGP drivers will likely
result in stability improvements. This should fix 855-class aperture
size detection.
Additionally, refuse to attach agp_i810 when some RAM is above 4GB and
the GART can't reference memory that high. This should be very rare.
The correct solution would be bus_dma conversion for agp, which is
beyond the scope of this change. Other AGP drivers could likely use
this change as well.
G33/Q35/Q33 AGP support is also included, but disconnected by default
due to lack of testing.
PR: kern/109724 (855 aperture issue)
Submitted by: FUJIMOTO Kou<fujimoto@j.dendai.ac.jp>
Approved by: re (hrs)
associated patch to XFree86 allows the X server to work with this chipset
on FreeBSD. Additional work will include porting the Linux 3D driver.
Submitted by: Ruslan Ermilov <ru@FreeBSD.org>
tested on Intel BX chipsets only. The other agp minidrivers are totally
untested.
The programming api is a subset of the Linux api and is only intended to
be enough for the X server to use. There is also an in-kernel api for the
use of other kernel modules such as the 3D DRI.