This fixes a problem where a CPU thread coming out of nap mode can
think it has valid values in the nonvolatile GPRs (r14 - r31) as saved
away in power7_idle, but in fact the values have been trashed because
the thread was used for KVM in the mean time.  The result is that the
thread crashes because code that called power7_idle (e.g.,
pnv_smp_cpu_kill_self()) goes to use values in registers that have
been trashed.

The bit field in SRR1 that tells whether state was lost only reflects
the most recent nap, which may not have been the nap instruction in
power7_idle.  So we need an extra PACA field to indicate that state
has been lost even if SRR1 indicates that the most recent nap didn't
lose state.  We clear this field when saving the state in power7_idle,
we set it to a non-zero value when we use the thread for KVM, and we
test it in power7_wakeup_noloss.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

At present, on the powernv platform, if you off-line a CPU that was
online, and then try to on-line it again, the kernel generates a
warning message "OPAL Error -1 starting CPU n".  Furthermore, if the
CPU is a secondary thread that was used by KVM while it was off-line,
the CPU fails to come online.

The first problem is fixed by only calling OPAL to start the CPU the
first time it is on-lined, as indicated by the cpu_start field of its
PACA being zero.  The second problem is fixed by restoring the
cpu_start field to 1 instead of 0 when using the CPU within KVM.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The minimum RMO size field in ibm,client-architecture is currently
ignored, but a future firmware version will rectify that. Since we
always get at least 128MB of RMO right now, asking for 64MB is
likely to result in boot failures.

We should bump it to at least 128MB, but considering all the boot
issues we have on 128MB RMO boxes and all new machines have virtual
RMO, we may as well set our minimum to 256MB.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

With CONFIG_STRICT_DEVMEM=y, user space cannot read any part of /dev/mem.
Since this breaks librtas, punch a hole in /dev/mem to allow access to the
rmo_buffer that librtas needs.

Anton Blanchard reported the problem and helped with the fix.

A quick test for this patch:

       # cat /proc/rtas/rmo_buffer
       000000000f190000 10000

       # python -c "print 0x000000000f190000 / 0x10000"
       3865

       # dd if=/dev/mem of=/tmp/foo count=1 bs=64k skip=3865
       1+0 records in
       1+0 records out
       65536 bytes (66 kB) copied, 0.000205235 s, 319 MB/s

       # dd if=/dev/mem of=/tmp/foo
       dd: reading `/dev/mem': Operation not permitted
       0+0 records in
       0+0 records out
       0 bytes (0 B) copied, 0.00022519 s, 0.0 kB/s
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

So I've had one of these for a while and it looks like the vendor never
bothered submitting the support upstream.

This adds it using ppc40x_simple and provides a device-tree.

There are some changes to the boot wrapper because the way u-boot works
on this thing, it seems to expect a multipart image with the kernel,
initrd and dtb in it.

The USB support is missing as it needs the yet unmerged driver for
the DWC OTG part and the GPIOs may need further definition in the dts.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

It's only used inside the same file where it's defined. There's
also no point exporting it anymore.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Open Firmware on OPAL machines seems to have issues if we close
stdin and/or we try to print things after calling "quiesce" so
we avoid doing both.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This adds some more interfaces for OPAL v2
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Define HUGETLB_NEED_PRELOAD in mmu-book3e.h for CONFIG_PPC64 instead
of having a much more complicated #if block.  This is easier to read
and maintain.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This avoids an extra find_vma() and is less error-prone.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Allow hugetlb to be enabled on 64b FSL_BOOK3E.  No platforms enable
it by default yet.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

For 64-bit FSL_BOOKE implementations, gigantic pages need to be
reserved at boot time by the memblock code based on the command line.
This adds the call that handles the reservation, and fixes some code
comments.

It also removes the previous pr_err when reserve_hugetlb_gpages
is called on a system without hugetlb enabled - the way the code is
structured, the call is unconditional and the resulting error message
spurious and confusing.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Before hugetlb, at each level of the table, we test for
!0 to determine if we have a valid table entry.  With hugetlb, this
compare becomes:
        < 0 is a normal entry
        0 is an invalid entry
        > 0 is huge

This works because the hugepage code pulls the top bit off the entry
(which for non-huge entries always has the top bit set) as an
indicator that we have a hugepage.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

I happened to comment this code while I was digging through it;
we might as well commit that.  I also made some whitespace
changes - the existing code had a lot of unnecessary newlines
that I found annoying when I was working on my tiny laptop.

No functional changes.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The original 32-bit hugetlb implementation used PPC64 vs PPC32 to
determine which code path to take.  However, the final hugetlb
implementation for 64-bit FSL ended up shared with the FSL
32-bit code so the actual check needs to be FSL_BOOK3E vs
everything else.  This patch changes the include protections to
reflect this.

There are also a couple of related comment fixes.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This updates the hugetlb page table code to handle 64-bit FSL_BOOKE.
The previous 32-bit work counted on the inner levels of the page table
collapsing.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This patch does 2 things: It corrects the code that determines the
size to write into MAS1 for the PPC_MM_SLICES case (this originally
came from David Gibson and I had incorrectly altered it), and it
changes the methodolody used to calculate the size for !PPC_MM_SLICES
to work for 64-bit as well as 32-bit.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

There was an unconditional return of "1" in the original code
from David Gibson, and I dropped it because it wasn't needed
for FSL BOOKE 32-bit.  However, not all systems (including 64-bit
FSL BOOKE) do loading of the hpte from the fault handler asm
and depend on this function returning 1, which causes a call
to update_mmu_cache() that writes an entry into the tlb.
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

If we don't have slices, we should be able to use the generic
hugetlb_get_unmapped_area() code
Signed-off-by: NBecky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The Cell and PowerMac platforms use virtually identical cascaded-IRQ
setup code, so just merge it into the core.  Ideally this code would
trigger automatically when an MPIC device-node specifies an "interrupts"
property, perhaps even enabling MPIC_SECONDARY along the way.

Unfortunately, Benjamin Herrenschmidt has had bad experiences in the
past with the quality of Apple PowerMac device-trees, so to be safe we
will only try to parse out an IRQ if the MPIC_SECONDARY flag is set by
the caller.
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Store the node pointer in the MPIC during initialization so that all of
the later operational code can just reuse the cached pointer.
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

There's not really any reason to have this one-liner in a separate
static inline function, given that all the other similar tests are
already in the alloc_mpic() code.
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Don't open-code the OpenFirmware "dcr-reg" property lookup trying to map
DCR resources.  This makes the code a bit easier to read.
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

It turns out that there are only 2 in-tree platforms which use MPICs
which are not "primary":  IBM Cell and PowerMac.  To reduce the
complexity of the typical board setup code, invert the MPIC_PRIMARY bit
into MPIC_SECONDARY.
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Almost all PowerPC platforms use a standard "open-pic" device node so
the mpic_alloc() function now accepts NULL for the device-node.  This
will cause it to perform a default search with of_find_matching_node().
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The MPIC code can already perform an automatic OF address translation
step as part of mpic_alloc(), but several boards need to use that base
address when they perform mpic_assign_isu().

The easiest solution is to save the computed physical address into the
"struct mpic" for later use by the board code.
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

All of the existing callers of mpic_alloc() pass in a non-NULL
device-node pointer, so the checks for a NULL device-node may be
removed.
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Instead of using the open-coded "reg" property lookup and address
translation in mpic_alloc(), directly call of_address_to_resource().
This includes various workarounds for special cases which the naive
of_address_translate() does not.

Afterwards it is possible to remove the copiously copy-pasted calls to
of_address_translate() from the 85xx/86xx/powermac platforms.
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This removes a bunch of "extern" declarations and CONFIG_SMP ifdefs.
Signed-off-by: NKyle Moffett <Kyle.D.Moffett@boeing.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Since commit 8a0a9bd4, this comment in mmap_rnd() does not
hold true as the value returned by get_random_int() will in fact be

different every single call. Remove the comment and simplify the code
back to its original desired form.

This reverts commit a5adc91a which is no longer necessary and
also fixes the sparc code that copied this same adjustment.
Signed-off-by: NDan McGee <dpmcgee@gmail.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

During kdump stress testing I sometimes see the kdump kernel panic
with:

  Interrupt 0x306 (real) is invalid, disabling it.
  Kernel panic - not syncing: bad return code EOI - rc = -4, value=ff000306

Instead of panicing print the error message, dump the stack the first
time it happens and continue on. Add some more information to the
debug messages as well.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

On a 64bit book3s machine I have an oops from a system reset that
claims the book3e CE bit was set:

MSR: 8000000000021032 <ME,CE,IR,DR>  CR: 24004082  XER: 00000010

On a book3s machine system reset sets IBM bit 46 and 47 depending on
the power saving mode. Separate the definitions by type and for
completeness add the rest of the bits in.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

In lieu of having multiple similiar lines, we can just have one
generic cpu-as line for CONFIG_ALTIVEC
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

CPC925/CPC945 use special window to access host bridge functionality of
u3-ht. Provide a way to access this device.
Signed-off-by: NDmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

As described in the help text in the patch, this token restricts general
access to /dev/mem as a way of increasing the security. Specifically, access
to exclusive IOMEM and kernel RAM is denied unless CONFIG_STRICT_DEVMEM is
set to 'n'.

Implement the 'devmem_is_allowed()' interface for Powerpc. It will be
called from range_is_allowed() when userpsace attempts to access /dev/mem.

This patch is based on an earlier patch from Steve Best and with input from
Paul Mackerras and Scott Wood.

[BenH] Fixed a typo or two and removed the generic change which should
       be submitted as a separate patch
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>