David S. Miller [Wed, 15 Feb 2006 00:42:11 +0000 (16:42 -0800)]
[SPARC64]: Restrict PCI bus scanning on SUN4V.
On the PBM's first bus number, only allow device 0, function 0, to be
poked at with PCI config space accesses.
For some reason, this single device responds to all device numbers.
Also, reduce the verbiage of the debugging log printk's for PCI cfg
space accesses in the SUN4V PCI controller driver, so that it doesn't
overwhelm the slow SUN4V hypervisor console.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Tue, 14 Feb 2006 02:09:44 +0000 (18:09 -0800)]
[SPARC64]: More SUN4V PCI work.
Get bus range from child of PCI controller root nexus.
This is actually a hack, but the PCI-E bridge sitting
at the top of the PCI tree responds to PCI config cycles
for every device number, so best to just ignore it for now.
Preliminary PCI irq routing, needs lots of work.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sat, 11 Feb 2006 08:29:34 +0000 (00:29 -0800)]
[SPARC64]: Simplify sun4v TLB handling using macros.
There was also a bug in sun4v_itlb_miss, it loaded the
MMU Fault Status base into %g3 instead of %g2.
This pointed out a fast path for TSB miss processing,
since we have %g2 with the MMU Fault Status base, we
can use that to quickly load up the PGD phys address.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 10 Feb 2006 23:39:51 +0000 (15:39 -0800)]
[SPARC64]: Use ASI_SCRATCHPAD address 0x0 properly.
This is where the virtual address of the fault status
area belongs.
To set it up we don't make a hypervisor call, instead
we call OBP's SUNW,set-trap-table with the real address
of the fault status area as the second argument. And
right before that call we write the virtual address into
ASI_SCRATCHPAD vaddr 0x0.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 10 Feb 2006 00:12:22 +0000 (16:12 -0800)]
[SPARC64]: Implement sun4v TSB miss handlers.
When we register a TSB with the hypervisor, so that it or hardware can
handle TLB misses and do the TSB walk for us, the hypervisor traps
down to these trap when it incurs a TSB miss.
Processing is simple, we load the missing virtual address and context,
and do a full page table walk.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 8 Feb 2006 10:53:50 +0000 (02:53 -0800)]
[SPARC64]: Sun4v interrupt handling.
Sun4v has 4 interrupt queues: cpu, device, resumable errors,
and non-resumable errors. A set of head/tail offset pointers
help maintain a work queue in physical memory. The entries
are 64-bytes in size.
Each queue is allocated then registered with the hypervisor
as we bring cpus up.
The two error queues each get a kernel side buffer that we
use to quickly empty the main interrupt queue before we
call up to C code to log the event and possibly take evasive
action.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Mon, 6 Feb 2006 06:27:28 +0000 (22:27 -0800)]
[SPARC64]: Sanitize %pstate writes for sun4v.
If we're just switching between different alternate global
sets, nop it out on sun4v. Also, get rid of all of the
alternate global save/restore in the OBP CIF trampoline code.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Mon, 6 Feb 2006 04:47:26 +0000 (20:47 -0800)]
[SPARC64]: Fill dead cycles on trap entry with real work.
As we save trap state onto the stack, the store buffer fills up
mid-way through and we stall for several cycles as the store buffer
trickles out to the L2 cache. Meanwhile we can do some privileged
register reads and other calculations, essentially for free.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sat, 4 Feb 2006 08:10:01 +0000 (00:10 -0800)]
[SPARC64]: Refine register window trap handling.
When saving and restoing trap state, do the window spill/fill
handling inline so that we never trap deeper than 2 trap levels.
This is important for chips like Niagara.
The window fixup code is massively simplified, and many more
improvements are now possible.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Mon, 27 Feb 2006 07:27:19 +0000 (23:27 -0800)]
[SPARC64]: Refine code sequences to get the cpu id.
On uniprocessor, it's always zero for optimize that.
On SMP, the jmpl to the stub kills the return address stack in the cpu
branch prediction logic, so expand the code sequence inline and use a
code patching section to fix things up. This also always better and
explicit register selection, which will be taken advantage of in a
future changeset.
The hard_smp_processor_id() function is big, so do not inline it.
Fix up tests for Jalapeno to also test for Serrano chips too. These
tests want "jbus Ultra-IIIi" cases to match, so that is what we should
test for.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 3 Feb 2006 00:16:24 +0000 (16:16 -0800)]
[SPARC64]: Turn off TSB growing for now.
There are several tricky races involved with growing the TSB. So just
use base-size TSBs for user contexts and we can revisit enabling this
later.
One part of the SMP problems is that tsb_context_switch() can see
partially updated TSB configuration state if tsb_grow() is running in
parallel. That's easily solved with a seqlock taken as a writer by
tsb_grow() and taken as a reader to capture all the TSB config state
in tsb_context_switch().
Then there is flush_tsb_user() running in parallel with a tsb_grow().
In theory we could take the seqlock as a reader there too, and just
resample the TSB pointer and reflush but that looks really ugly.
Lastly, I believe there is a case with threads that results in a TSB
entry lock bit being set spuriously which will cause the next access
to that TSB entry to wedge the cpu (since the TSB entry lock bit will
never clear). It's either copy_tsb() or some bug elsewhere in the TSB
assembly.
Signed-off-by: David S. Miller <davem@davemloft.net>
The are distrupting, which by the sparc v9 definition means they
can only occur when interrupts are enabled in the %pstate register.
This never occurs in any of the trap handling code running at
trap levels > 0.
So just mark it as an unexpected trap.
This allows us to kill off the cee_stuff member of struct thread_info.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 1 Feb 2006 23:55:21 +0000 (15:55 -0800)]
[SPARC64]: Access TSB with physical addresses when possible.
This way we don't need to lock the TSB into the TLB.
The trick is that every TSB load/store is registered into
a special instruction patch section. The default uses
virtual addresses, and the patch instructions use physical
address load/stores.
We can't do this on all chips because only cheetah+ and later
have the physical variant of the atomic quad load.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 1 Feb 2006 02:35:05 +0000 (18:35 -0800)]
[SPARC64]: Don't clobber alt-global %g4 on window fixups.
If we are returning back to kernel mode, %g4 could be live
(for example, in the case where we window spill in the etrap
code). So do not change it's value if going back to kernel.
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 1 Feb 2006 02:34:51 +0000 (18:34 -0800)]
[SPARC64]: Fix race in LOAD_PER_CPU_BASE()
Since we use %g5 itself as a temporary, it can get clobbered
if we take an interrupt mid-stream and thus cause end up with
the final %g5 value too early as a result of rtrap processing.
Set %g5 at the very end, atomically, to avoid this problem.
Signed-off-by: David S. Miller <davem@davemloft.net>
projects / linux-2.6 / log