Commit graph

1113 commits

Author SHA1 Message Date
Aurelien Jarno
909eedb74f target-ppc: slightly optimize lfiwax
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2013-04-27 00:37:46 +02:00
Aurelien Jarno
7d08d85645 target-ppc: add support for extended mtfsf/mtfsfi forms
Power ISA 2.05 adds support for extended mtfsf/mtfsfi form, with a new
W field to select the upper part of the FPCSR register.

For that the helper is changed to handle 64-bit input values and mask with
up to 16 bits. The mtfsf/mtfsfi instructions do not have the W bit
marked as invalid anymore. Instead this is checked in the helper, which
therefore needs to access to the insns/insns_flags2. They are added in
the DisasContext struct. Finally change all accesses to the opcode fields
through extract helpers, prefixed with FP for consistency.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:43 +02:00
Aurelien Jarno
44bc0c4d3e target-ppc: emulate store doubleword pair instructions
Needed for Power ISA version 2.05 compliance. The check for odd register
pairs is done using the invalid bits.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:43 +02:00
Aurelien Jarno
05050ee804 target-ppc: emulate load doubleword pair instructions
Needed for Power ISA version 2.05 compliance. The check for odd register
pairs is done using the invalid bits.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:43 +02:00
Aurelien Jarno
199f830d19 target-ppc: emulate lfiwax instruction
Needed for Power ISA version 2.05 compliance.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
[agraf: fix tcg debug error]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:43 +02:00
Aurelien Jarno
f03328882f target-ppc: emulate fcpsgn instruction
Needed for Power ISA version 2.05 compliance.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:42 +02:00
Aurelien Jarno
725bcec288 target-ppc: emulate prtyw and prtyd instructions
Needed for Power ISA version 2.05 compliance.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
[agraf: fix 32-bit host compile, simplify code]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:42 +02:00
Aurelien Jarno
fcfda20f2f target-ppc: emulate cmpb instruction
Needed for Power ISA version 2.05 compliance.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:42 +02:00
Aurelien Jarno
9c2627b09d target-ppc: add instruction flags for Book I 2.05
.. and enable it on POWER7 CPU.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:42 +02:00
Aurelien Jarno
bf45a2e67c target-ppc: optimize fabs, fnabs, fneg
fabs, fnabs and fneg are just flipping the bit sign of an FP register,
this can be implemented in TCG instead of using softfloat.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:42 +02:00
Alexander Graf
414f5d1448 PPC: Fix dcbz for linux-user on 970
The default with linux-user for dcbz on 970 is to emulate 32 byte clears.
However, redoing the dcbzl support we added a check to not honor the bit
in HID5 that sets this.

Remove the #ifdef check on linux user, so that we get 32 byte clears again.

Reported-by: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:42 +02:00
Tristan Gingold
db72c9f256 powerpc: correctly handle fpu exceptions.
Raise the exception on the first occurence, do not wait for the next
floating point operation.

Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:42 +02:00
David Gibson
9b00ea4906 target-ppc: Synchronize VPA state with KVM
For PAPR guests, KVM tracks the various areas registered with the
H_REGISTER_VPA hypercall.  For full emulation, of course, these are tracked
within qemu.  At present these values are not synchronized.  This is a
problem for reset (qemu's reset of the VPA address is not pushed to KVM)
and will also be a problem for savevm / migration.

The kernel now supports accessing the VPA state via the ONE_REG interface,
this patch adds code to qemu to use that interface to keep the qemu and
KVM ideas of the VPA state synchronized.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:41 +02:00
David Gibson
702763fa32 target-ppc: Add more stubs for POWER7 PMU registers
In addition to the performance monitor registers found on nearly all
6xx chips, the POWER7 has two additional counters (PMC5 & PMC6) and an
extra control register (MMCRA).  This patch adds stub support for them to
qemu - the registers won't do anything, but with this change won't cause
illegal instruction traps accessing them.  They're also registered with
their ONE_REG ids, so their value will be kept in sync with KVM where
appropriate.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:41 +02:00
David Gibson
0cbad81f70 pseries: Fixes and enhancements to L1 cache properties
PAPR requires that the device tree's CPU nodes have several properties
with information about the L1 cache.  We already create two of these
properties, but with incorrect names - "[id]cache-block-size" instead
of "[id]-cache-block-size" (note the extra hyphen).

We were also missing some of the required cache properties.  This
patch adds the [id]-cache-line-size properties (which have the same
values as the block size properties in all current cases).  We also
add the [id]-cache-size properties.

Adding the cache sizes requires some extra infrastructure in the
general target-ppc code to (optionally) set the cache sizes for
various CPUs.  The CPU family descriptions in translate_init.c can set
these sizes - this patch adds correct information for POWER7, I'm
leaving other CPU types to people who have a physical example to
verify against.  In addition, for -cpu host we take the values
advertised by the host (if available) and use those to override the
information based on PVR.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:41 +02:00
David Gibson
f36951c19f pseries: Fix incorrect calculation of RMA size in certain configurations
For the pseries machine, we need to advertise to the guest the size of its
RMA - that is the amount of memory it can access with the MMU off.  For HV
KVM, this is constrained by the hardware limitations on the virtual RMA of
one hash PTE per PTE group in the hash page table.  We already had code to
calculate this, but it was assuming the VRMA page size was the same as the
(host) backing page size for guest RAM.

In the case of a host kernel configured for 64k base page size, but running
on hardware (or firmware) which only allows 4k pages, the hose will do all
its allocations with a 64k page size, but still use 4k hardware pages for
actual mappings.  Usually that's transparent to things running under the
host, but in the case of the maximum VRMA size it's not.

This patch refines the RMA size calculation to instead use the largest
available hardware page size (as reported by the SMMU_INFO call) which is
less than or equal to the backing page size.  This now gives the correct
RMA size in all cases I've tested.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:41 +02:00
Bharat Bhushan
31f2cb8ff4 Enable kvm emulated watchdog
Enable the KVM emulated watchdog if KVM supports (use the
capability enablement in watchdog handler). Also watchdog exit
(KVM_EXIT_WATCHDOG) handling is added.
Watchdog state machine is cleared whenever VM state changes to running.
This is to handle the cases like return from debug halt etc.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
[agraf: rebase to current code base, fix non-kvm cases]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:40 +02:00
Richard Henderson
752d634ecc target-ppc: Fix narrow-mode add/sub carry output
Broken in b5a73f8d8a, the carry itself was
fixed in 79482e5ab3.  But we still need to
produce the full 64-bit addition.

Simplify the conditions at the top of the functions for when we need a
new temporary.  Only plain addition is important enough to warrent avoiding
the temporary, and the extra tcg move op that would come with it.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Tested-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:40 +02:00
Fabien Chouteau
2bc173224a PPC: Add breakpoint registers for 603 and e300
Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:40 +02:00
Fabien Chouteau
09d9828ace PPC: fix hreset_vector for 60x, 7x0, 7x5, G2, MPC8xx, MPC5xx, 7400 and 7450
According to the different user's manuals, the vector offset for system
reset (both /HRESET and /SRESET) is 0x00100.

This patch may break support of some executables, as the power-on start
address may change. For a specific board, if the power-on start address
is different than HRESET vector (i.e. 0x00000100 or 0xfff00100), this
should be fixed in board's initialization code.

Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:40 +02:00
Aurelien Jarno
8e7a6db965 target-ppc: fix nego and subf*o instructions
The overflow computation of nego and subf*o instructions has been broken
in commit ffe30937. Contrary to other targets, the instruction is subtract
from an not subtract on PowerPC.

This patch fixes the issue by using the correct argument in the xor
computation. Thanks to Peter Maydell for the hint.

With this change the PPC emulation passes the Gwenole Beauchesne
testsuite again.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:40 +02:00
Fabien Chouteau
2cf3eb6df5 PPC: Remove env->hreset_excp_prefix
This value is not needed if we use correctly the MSR[IP] bit.

excp_prefix is always 0x00000000, except when the MSR[IP] bit is
implemented and set to 1, in that case excp_prefix is 0xfff00000.

The handling of MSR[IP] was already implemented but not used at reset
because the value of env->msr was changed "manually".

The patch uses the function hreg_store_msr() to set env->msr, this
ensures a good handling of MSR[IP] at reset, and therefore a good value
for excp_prefix.

Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:40 +02:00
Stuart Yoder
3b961124bf PPC: e500: advertise 4.2 MPIC only if KVM supports EPR
Older KVM versions don't support EPR which breaks guests when we announce
MPIC variants that support EPR.

Catch that case and expose only MPIC version 2.0 which tells the guest that
we don't support the EPR capability yet.

Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
[agraf: Add comment, route cap check through kvm_ppc.c]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:40 +02:00
Aurelien Jarno
e71ec2e93d target-ppc: Enable ISEL on POWER7
ISEL is a Power ISA 2.06 instruction and thus is available on POWER7.
Given this is trapped and emulated by the Linux kernel, I guess it went
unnoticed.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 23:02:39 +02:00
Paolo Bonzini
b421d9c6ab memory: move core typedefs to qemu/typedefs.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-15 18:19:26 +02:00
Paolo Bonzini
0d09e41a51 hw: move headers to include/
Many of these should be cleaned up with proper qdev-/QOM-ification.
Right now there are many catch-all headers in include/hw/ARCH depending
on cpu.h, and this makes it necessary to compile these files per-target.
However, fixing this does not belong in these patches.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-08 18:13:10 +02:00
Richard Henderson
9ca3f7f316 target-ppc: Use NARROW_MODE macro for tlbie
Removing conditional compilation in the process.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:54 +01:00
Richard Henderson
c791fe8436 target-ppc: Use NARROW_MODE macro for addresses
Removing conditional compilation in the process.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:54 +01:00
Richard Henderson
02765534f7 target-ppc: Use NARROW_MODE macro for comparisons
Removing conditional compilation in the process.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:54 +01:00
Richard Henderson
e0c8f9ce85 target-ppc: Use NARROW_MODE macro for branches
Removing conditional compilation in the process.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:54 +01:00
Richard Henderson
79482e5ab3 target-ppc: Fix add and subf carry generation in narrow mode
The set of computations used in b5a73f8d8a
are only valid if the current word size == target_long size.  This failed
to take ppc64 in 32-bit (narrow) mode into account.

Add a NARROW_MODE macro to avoid conditional compilation.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:54 +01:00
David Gibson
b632a148b6 target-ppc: Use QOM method dispatch for MMU fault handling
After previous cleanups, the many scattered checks of env->mmu_model in
the ppc MMU implementation have, at least for "classic" hash MMUs been
reduced (almost) to a single switch at the top of
cpu_ppc_handle_mmu_fault().

An explicit switch is still a pretty ugly way of handling this though.  Now
that Andreas Färber's CPU QOM cleanups for ppc have gone in, it's quite
straightforward to instead make the handle_mmu_fault function a QOM method
on the CPU object.

This patch implements such a scheme, initializing the method pointer at
the same time as the mmu_model variable.  We need to keep the latter around
for now, because of the MMU types (BookE, 4xx, et al) which haven't been
converted to the new scheme yet, and also for a few other uses.  It would
be good to clean those up eventually.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:53 +01:00
David Gibson
eb20c1c6da target-ppc: Move ppc tlb_fill implementation into mmu_helper.c
For softmmu builds the interface from the generic code to the target
specific MMU implementation is through the tlb_fill() function.  For ppc
this is currently in mem_helper.c, whereas it would make more sense in
mmu_helper.c.  This patch moves it, which also allows
cpu_ppc_handle_mmu_fault() to become a local function in mmu_helper.c

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:53 +01:00
David Gibson
cc8eae8ac7 target-ppc: Split user only code out of mmu_helper.c
mmu_helper.c is, for obvious reasons, almost entirely concerned with
softmmu builds of qemu.  However, it does contain one stub function which
is used when CONFIG_USER_ONLY=y - the user only versoin of
cpu_ppc_handle_mmu_fault, which always triggers an exception.  The entire
rest of the file is surrounded by #if !defined(CONFIG_USER_ONLY).

We clean this up by moving the user only stub into its own new file,
removing the ifdefs and building mmu_helper.c only when CONFIG_SOFTMMU
is set.  This also lets us remove the #define of cpu_handle_mmu_fault to
cpu_ppc_handle_mmu_fault - that name is only used from generic code for
user only - so we just name our split user version by the generic name.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:53 +01:00
David Gibson
f80872e21c mmu-hash64: Implement Virtual Page Class Key Protection
Version 2.06 of the Power architecture describes an additional page
protection mechanism.  Each virtual page has a "class" (0-31) recorded in
the PTE.  The AMR register contains bits which can prohibit reads and/or
writes on a class by class basis.  Interestingly, the AMR is userspace
readable and writable, however user mode writes are masked by the contents
of the UAMOR which is privileged.

This patch implements this protection mechanism, along with the AMR and
UAMOR SPRs.  The architecture also specifies a hypervisor-privileged AMOR
register which masks user and supervisor writes to the AMR and UAMOR.  We
leave this out for now, since we don't at present model hypervisor mode
correctly in any case.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[agraf: fix 32-bit hosts]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:53 +01:00
David Gibson
caa597bd9f mmu-hash*: Merge translate and fault handling functions
ppc_hash{32,64}_handle_mmu_fault() is now the only caller of
ppc_hash{32,64{_translate(), so this patch combines them together.  This
means that instead of one returning a variety of non-obvious error codes
which then get translated into the various mmu exception conditions, we can
just generate the exceptions as we discover problems in the translation
path.  This also removes the last usage of mmu_ctx_hash{32,64}.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:53 +01:00
David Gibson
5883d8b296 mmu-hash*: Don't use full ppc_hash{32, 64}_translate() path for get_phys_page_debug()
Currently the hash mmu versionsof get_phys_page_debug() use the same
ppc64_hash64_translate() function to do the translation logic as the normal
mm fault handler code.

That sounds like a good idea, but has some complications. The debug path
doesn't need, or even want some parts of the full translation path, like
permissions checking.  Furthermore, the pte flags update included in the
normal path means that the debug call is not quite side effect free.

This patch, therefore, reimplements get_phys_page_debug as the minimal
required subset of the full translation path.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>`z
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:53 +01:00
David Gibson
75d5ec89c0 mmu-hash*: Correctly mask RPN from hash PTE
BEHAVIOUR CHANGE

At present we take the whole of word 1 of the hash PTE as the real page
number used to calculate the translated address.  This is incorrect,
because it leaves the flags from the low bits of PTE word 1 in place in the
rpm.  We mostly get away with that because the value is later masked by
TARGET_PAGE_MASK.

More recent 64-bit CPUs also have a small number of flag bits (PP0 and
KEY) in the top bits of PTE word 1.  Any guest which used those bits would
fail with the current code.

This patch fixes the problem by correctly masking out the RPN field of
PTE word 1.  This is safe, even for older CPUs which didn't have PP0 and
KEY, because although the RPN notionally extended to the very top of PTE
word 1, none of those CPUs actually implemented that many real address
bits.

We add analogous masking to the 32-bit code, even though it also doesn't
have the high flag bits, for consistency and clarity.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:53 +01:00
David Gibson
6d11d998bb mmu-hash*: Clean up real address calculation
More recent 64-bit hash MMUs support multiple page sizes, and PTEs for
large pages only include the offset of the whole large page.  But the qemu
tlb only handles pages of the base size (4k) so we need to break up the
large pages into 4k pieces for the qemu tlb.  To do that we have a somewhat
awkward piece of code that adds the folds address bits 4k and the page size
from the virtual address into the real address from the pte.

This patch simplifies this redefining the raddr output of
ppc_hash64_translate() to be the full real address of the faulting address,
rather than just the (4k) page offset.  Computing that turns out to be
simpler, and is fine for the caller, since it already masks with
TARGET_PAGE_MASK before inserting into the qemu tlb.

The multiple page size complication doesn't exist for 32-bit hash mmus, but
we make an analogous cleanup there for consistency.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:52 +01:00
David Gibson
b344074642 mmu-hash*: Clean up PTE flags update
Currently the ppc_hash{32,64}_pte_update_flags() helper functions update a
PTE's referenced and changed bits as necessary to reflect the access.  It
is somewhat long winded, though.  This patch open codes them in their
(single) callers, in a simpler way.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:52 +01:00
David Gibson
57d0a39d98 mmu-hash64: Factor SLB N bit into permissions bits
BEHAVIOUR CHANGE

Currently, for 64-bit hash mmu, the execute protection bit placed into the
qemu tlb is based only on the N (No execute) bit from the PTE.  However,
No Execute can also be set at the segment level.  We do check this on
execute faults, but this still means we could incorrectly allow execution
of code from a No Execute segment, if a prior read or write fault caused
the page to be loaded into the qemu tlb with PROT_EXEC set.

To correct this, we (re-)check the segment level no execute permission when
generating the protection bits for the qemu tlb.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:52 +01:00
David Gibson
e01b444523 mmu-hash*: Clean up permission checking
Currently checking of PTE permission bits is split messily amongst
ppc_hash{32,64}_pp_check(), ppc_hash{32,64}_check_prot() and their callers.
This patch cleans this up to have the new function
ppc_hash{32,64}_pte_prot() compute the page permissions from the SLBE (for
64-bit) or segment register (32-bit) and the pte.  A greatly simplified
version of the actual permissions check is then open coded in the callers.

The 32-bit version of ppc_hash32_pte_prot() is implemented in terms of
ppc_hash32_pp_prot(), a renamed and slightly cleaned up version of the old
ppc_hash32_pp_check(), which is also used for checking BAT permissions on
the 601.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:52 +01:00
David Gibson
e1a53ba2e0 mmu-hash32: Remove nx from context structure
Previous cleanups have meant the nx field of the mmu_ctx_hash32 structure
is now only used within ppc_hash32_translate(), and so it can be replaced
by a local variable.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:52 +01:00
David Gibson
87dc3fd13e mmu-hash*: Don't update PTE flags when permission is denied
BEHAVIOUR CHANGE

Currently if ppc_hash{32,64}_translate() finds a PTE matching the given
virtual address, it will always update the PTE's R & C (Referenced and
Changed) bits.  This happens even if the PTE's permissions mean we are
about to deny the translation.

This is clearly a bug, although we get away with it because:
  a) It will only incorrectly set, never reset the bits, which should not
cause guest correctness problems.
  b) Linux guests never use the R & C bits anyway.

This patch fixes the behaviour, only updating R & C when access is granted
by the PTE.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:52 +01:00
David Gibson
59acbe2855 mmu-hash32: Don't look up page tables on BAT permission error
BEHAVIOUR CHANGE

Currently, on any failure translating an address with BATs, we proceed to
normal segment and page table translation.  That's incorrect if the
BAT error was due to permissions, rather than not finding a matching BAT.
We've gotten away with it because a guest would not usually put
translations for the same address in both BATs and page table.  Nonetheless
this patch corrects the logic, only doing page table lookup if no BAT
is found.  A matching BAT with bad permissions will now correctly trigger
an exception.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:51 +01:00
David Gibson
145e52f318 mmu-hash32: Cleanup BAT lookup
This patch makes a general cleanup of the ppc_hash32_get_bat() function,
renaming it to ppc_hash32_bat_lookup().  In particular, the new function
only looks for a matching BAT, with the permissions check from the old
function moved to the caller.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:51 +01:00
David Gibson
6fc76aa9ad mmu-hash32: Clean up BAT matching logic
The code to search for a matching BAT for a virtual address is somewhat
longwinded and awkward.  In particular, it relies on seperate size and
validity information being returned from the hash32_bat_size() function
(and 601 specific variant).

We simplify this by having hash32_bat_size() return instead a mask of the
virtual address bits to match, and 0 for invalid (since a BAT can never
match the entire address space).

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:51 +01:00
David Gibson
e1d4951593 mmu-hash32: Split BAT size logic from permissions logic
hash32_bat_size_prot() and its 601 variant, as the name suggests, returns
both a BAT's size - needed to search for a matching BAT - and its
permissions, only relevant once a matching BAT has been located.

There's no particular advantage to combining these, so we split these roles
into seperate functions for clarity.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:51 +01:00
David Gibson
9986ed1ed0 mmu-hash32: Remove odd pointer usage from BAT code
In the code for handling BATs, the hash32_bat_size_prot() and
hash32_bat_601_size_prot() functions are passed the BAT contents by
reference (pointer) for no clear reason, since they only need the values
within.

This patch removes this odd usage, and uses the resulting change to clean
up the caller slightly.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:51 +01:00
David Gibson
6a9801106e mmu-hash*: Fold pte_check*() logic into caller
With previous cleanups made, the 32-bit and 64-bit pte_check*() functions
are pretty trivial and only have one call site.  This patch therefore
clarifies the overall code flow by folding those functions into their
call site.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:51 +01:00