The UltraSPARC T1 manual recommends this because the chip
could instruction prefetch into the VA hole, and this would
also make decoding  certain kinds of memory access traps
more difficult (because the chip sign extends certain pieces
of trap state).
Signed-off-by: David S. Miller <davem@davemloft.net>

First of all, use the known _PAGE_EXEC_{4U,4V} value instead
of loading _PAGE_EXEC from memory.  We either know which one
to use by context, or we can code patch the test.

Next, we need to check executability of a PTE in the generic
TSB miss handler.
Signed-off-by: David S. Miller <davem@davemloft.net>

Should put FAULT_CODE_DTLB into %g3 not FAULT_CODE_ITLB.
Signed-off-by: David S. Miller <davem@davemloft.net>

These are all implemented inline earlier in the file.
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

There were several bugs in the SUN4V cpu mondo dispatch code.

In fact, if we ever got a EWOULDBLOCK or other error from
the hypervisor call, we'd potentially send a cpu mondo multiple
times to the same cpu and even worse we could loop until the
timeout resending the same mondo over and over to such cpus.

So let's bulletproof this thing as follows:

1) Implement cpu_mondo_send() and cpu_state() hypervisor calls
   in arch/sparc64/kernel/entry.S, add prototypes to asm/hypervisor.h

2) Don't build and update the cpulist using inline functions, this
   was causing the cpu mask to not get updated in the caller.

3) Disable interrupts during the entire mondo send, otherwise our
   cpu list and/or mondo block could get overwritten if we take
   an interrupt and do a cpu mondo send on the current cpu.

4) Check for all possible error return types from the cpu_mondo_send()
   hypervisor call.  In particular:

   HV_EOK) Our work is done, all cpus have received the mondo.
   HV_CPUERROR) One or more of the cpus in the cpu list we passed
                to the hypervisor are in error state.  Use cpu_state()
                calls over the entries in the cpu list to see which
		ones.  Record them in "error_mask" and report this
		after we are done sending the mondo to cpus which are
		not in error state.
   HV_EWOULDBLOCK) We need to keep trying.

   Any other error we consider fatal, we report the event and exit
   immediately.

5) We only timeout if forward progress is not made.  Forward progress
   is defined as having at least one cpu get the mondo successfully
   in a given cpu_mondo_send() call.  Otherwise we bump a counter
   and delay a little.  If the counter hits a limit, we signal an
   error and report the event.

Also, smp_call_function_mask() error handling reports the number
of cpus incorrectly.
Signed-off-by: David S. Miller <davem@davemloft.net>

1) We must flush the TLB, duh.

2) Even if the sw context was seen to be valid, the local cpu's
   hw context can be out of date, so reload it unconditionally.
Signed-off-by: David S. Miller <davem@davemloft.net>

Need to shift back up by 3 bits to get 8-byte entry
index.
Signed-off-by: David S. Miller <davem@davemloft.net>

We no longer have the problems that require using the smaller
sizes.
Signed-off-by: David S. Miller <davem@davemloft.net>

It is totally wasted work, since we have no D-cache aliasing
issues on sun4v.
Signed-off-by: David S. Miller <davem@davemloft.net>

Check TLB flush hypervisor calls for errors and report them.

Pass HV_MMU_ALL always for now, we can add back the optimization
to avoid the I-TLB flush later.

Always explicitly page align the virtual address arguments.
Signed-off-by: David S. Miller <davem@davemloft.net>

It's in "arg0" not "func".
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

get_new_mmu_context() can be invoked from interrupt context
now for the new SMP version wrap handling.

So disable interrupt while taking ctx_alloc_lock in destroy_context()
so we don't deadlock.
Signed-off-by: David S. Miller <davem@davemloft.net>

The context allocation scheme we use depends upon there being a 1<-->1
mapping from cpu to physical TLB for correctness.  Chips like Niagara
break this assumption.

So what we do is notify all cpus with a cross call when the context
version number changes, and if necessary this makes them allocate
a valid context for the address space they are running at the time.

Stress tested with make -j1024, make -j2048, and make -j4096 kernel
builds on a 32-strand, 8 core, T2000 with 16GB of ram.
Signed-off-by: David S. Miller <davem@davemloft.net>

Otherwise with too much stuff enabled in the kernel config
we can end up with an unaligned trap table.
Signed-off-by: David S. Miller <davem@davemloft.net>

SBUS flash driver needs it.

Noticed by Fabbione.
Signed-off-by: David S. Miller <davem@davemloft.net>

Niagara helps us find a ancient bug in the sparc64 port :-)

The ASI_* values are plain constant defines, thus signed 32-bit
on sparc64.  To put shift this into the regs->tstate value we were
doing or'ing "(ASI_PNF << 24)" into there.

ASI_PNF is 0x82 and shifted left by 24 makes that topmost bit the
sign bit in a 32-bit value.  This would get sign extended to 64-bits
and thus corrupt the top-half of the reg->tstate value.

This never caused problems in pre-Niagara cpus because the only thing
up there were the condition code values.  But Niagara has the global
register level field, and this all 1's value is illegal there so
Niagara gives an illegal instruction trap due to this bug.

I'm pretty sure this bug is about as old as the sparc64 port itself.

This also points out that we weren't setting ASI_PNF for 32-bit tasks.
We should, so fix that while we're here.
Signed-off-by: David S. Miller <davem@davemloft.net>

If we take a window fault, on SUN4V set %gl to zero before we
turn PSTATE_IE back on in %pstate.  Otherwise if we take an
interrupt we'll end up with corrupt register state.
Signed-off-by: David S. Miller <davem@davemloft.net>

It can map all of the linear kernel mappings with zero TSB hash
conflicts for systems with 16GB or less ram.  In such cases, on
SUN4V, once we load up this TSB the first time with all the
mappings, we never take a linear kernel mapping TLB miss ever
again, the hypervisor handles them all.
Signed-off-by: David S. Miller <davem@davemloft.net>

We use a bitmap, one bit for every 256MB of memory.  If the
bit is set we can use a 256MB PTE for linear mappings, else
we have to use a 4MB PTE.

SUN4V support is there, and we can very easily add support
for Panther cpu 256MB PTEs in the future.
Signed-off-by: David S. Miller <davem@davemloft.net>

We have to turn off the "polling nrflag" bit when we sleep
the cpu like this, so that we'll get a cross-cpu interrupt
to wake the processor up from the yield.

We also have to disable PSTATE_IE in %pstate around the yield
call and recheck need_resched() in order to avoid any races.
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

Set, but never used.

We used to use this for dynamic IRQ retargetting, but that
code died a long time ago.
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

They were getting truncated to 32-bit and this is very bad
when your MMU fault status area is in physical memory above
4GB on SUN4V.
Signed-off-by: David S. Miller <davem@davemloft.net>

The math-emu code only expects unfinished fpop traps when
emulating FPU sqrt instructions on pre-Niagara chips.
On Niagara we can get unimplemented fpop, so handle that.
Signed-off-by: David S. Miller <davem@davemloft.net>

Because we play this trick where we use ttyS? in increasing minor
numbers for different sunfoo.c drivers, we have to inform the TTY
layer of this.

Do so by setting the tty->name_base appropriately.

Probably there should be a generic way to do this in the serial core,
but for now...
Signed-off-by: David S. Miller <davem@davemloft.net>

Should be "Dax" not "Iax".
Signed-off-by: David S. Miller <davem@davemloft.net>

By simply changing the do-while loop into a plain
while loop.
Signed-off-by: David S. Miller <davem@davemloft.net>

I forgot to remove the one in pci_4v_map_sg() during the
iommu batching commit.
Signed-off-by: David S. Miller <davem@davemloft.net>

Actually make use of the 'limit' we compute.
Signed-off-by: David S. Miller <davem@davemloft.net>

It's extremely noisy and causes much grief on slow
consoles with large numbers of cpus.

We'll have to provide this some saner way in order
to re-enable this.
Signed-off-by: David S. Miller <davem@davemloft.net>

Use a batching queue system for IOMMU mapping setup,
with a page sized batch.
Signed-off-by: David S. Miller <davem@davemloft.net>

We're about to seriously die in these cases so it is important
that the messages make it to the console.
Signed-off-by: David S. Miller <davem@davemloft.net>

Another case where we have to force ourselves into global register
level one.  Also make sure the arguments passed to sun4v_do_mna() are
correct.

This area actually needs some more work, for example spill fixup is
not necessarily going to do the right thing for this case.
Signed-off-by: David S. Miller <davem@davemloft.net>

Just like kvmap_dtlb_longpath we have to force the
global register level to one in order to mimick the
PSTATE_MG --> PSTATE_AG trasition done on SUN4U.
Signed-off-by: David S. Miller <davem@davemloft.net>