For various reasons, this ioctl was a bad idea.
At channel creation we now automatically create DMA objects covering
available VRAM and GART memory, where the client used to do this themselves.
However, there is still a need to be able to create DMA objects pointing at
specific areas of memory (ie. notifiers). Each channel is now allocated a
small amount of memory from which a client can suballocate things (such as
notifiers), and have a DMA object created which covers the suballocated area.
The NOTIFIER_ALLOC ioctl exposes this functionality.
NV04/NV10 load_context()/save_context() are stubs. I don't know enough about
how they work to implement them sanely. The "old" context_switch() code
remains hooked up, so it shouldn't break anything.
NV20 will probably break if load_context() works. No inital context values
are filled in, so when the first channel is created PGRAPH will probably end
up having its state zeroed. Some setup from nv20_graph_init() will probably
need to be moved to the per-channel context setup.
Commit 9b01bd5b284bbf519b726b39f1352023cb5e9e69 introduced a
compat_ioctl handler for RADEON_SETPARAM, the sole purpose of which was
to handle the fact that on i386, alignof(uint64_t)==4.
Unfortunately, this handler was installed for _all_ 64-bit
architectures, instead of only x86_64 and ia64. And thus it breaks
32-bit compatibility on every other arch, where 64-bit integers are
aligned to 8 bytes in 32-bit mode just the same as in 64-bit mode.
Arnd has a cunning plan to use 'compat_u64' with appropriate alignment
attributes according to the 32-bit ABI, but for now let's just make the
compat_radeon_cp_setparam routine entirely disappear on 64-bit machines
whose 32-bit compat support isn't for i386. It would be a no-op with
compat_u64 anyway.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Thomas Hellstrom
Ian Romanick
Ben Skeggs
Michel Dänzer
Oliver McFadden
David Woodhouse