Commit Graph

1158 Commits (a9fd16544dd3cdc50902ff652e2f57982f113497)

Author SHA1 Message Date
Peter Maydell 2472b6c07b gdbstub: Allow target CPUs to specify watchpoint STOP_BEFORE_ACCESS flag
GDB assumes that watchpoint set via the gdbstub remote protocol will
behave in the same way as hardware watchpoints for the target. In
particular, whether the CPU stops with the PC before or after the insn
which triggers the watchpoint is target dependent. Allow guest CPU
code to specify which behaviour to use. This fixes a bug where with
guest CPUs which stop before the accessing insn GDB would manually
step forward over what it thought was the insn and end up one insn
further forward than it should be.

We set this flag for the CPU architectures which set
gdbarch_have_nonsteppable_watchpoint in gdb 7.7:
ARM, CRIS, LM32, MIPS and Xtensa.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Tested-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Tested-by: Michael Walle <michael@walle.cc> (for lm32)
Message-id: 1410545057-14014-1-git-send-email-peter.maydell@linaro.org
2014-10-06 14:25:43 +01:00
Edgar E. Iglesias 136e67e9b5 target-arm: Add support for VIRQ and VFIQ
This only implements the external delivery method via the GIC.

Acked-by: Greg Bellows <greg.bellows@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-12-git-send-email-edgar.iglesias@gmail.com
[PMM: adjusted following cpu-exec refactoring]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:51 +01:00
Edgar E. Iglesias 041c96666d target-arm: Add IRQ and FIQ routing to EL2 and 3
Reviewed-by: Greg Bellows <greg.bellows@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-11-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:51 +01:00
Edgar E. Iglesias e0d6e6a5e7 target-arm: A64: Emulate the SMC insn
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-10-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:50 +01:00
Edgar E. Iglesias 607d98b81e target-arm: Add a Hypervisor Trap exception type
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-9-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:50 +01:00
Edgar E. Iglesias 35979d71c4 target-arm: A64: Emulate the HVC insn
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-8-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:50 +01:00
Edgar E. Iglesias 2dd081ae76 target-arm: A64: Correct updates to FAR and ESR on exceptions
Not all exception types update both FAR and ESR.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Greg Bellows <greg.bellows@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-7-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:50 +01:00
Edgar E. Iglesias dfafd09088 target-arm: Don't take interrupts targeting lower ELs
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Greg Bellows <greg.bellows@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-6-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:49 +01:00
Edgar E. Iglesias 043b7f8d12 target-arm: Break out exception masking to a separate func
Reviewed-by: Greg Bellows <greg.bellows@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-5-git-send-email-edgar.iglesias@gmail.com
[PMM: updated to account for recent cpu-exec refactoring]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:49 +01:00
Edgar E. Iglesias 9e729b57ac target-arm: A64: Refactor aarch64_cpu_do_interrupt
Introduce new_el and new_mode in preparation for future patches
that add support for taking exceptions to and from EL2 and 3.
No functional change.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-4-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:49 +01:00
Edgar E. Iglesias 64e0e2de0c target-arm: Add SCR_EL3
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-3-git-send-email-edgar.iglesias@gmail.com
[PMM: apply offsetoflow32() to correct regdef]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:49 +01:00
Edgar E. Iglesias f149e3e847 target-arm: Add HCR_EL2
Reviewed-by: Greg Bellows <greg.bellows@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1411718914-6608-2-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-29 18:48:48 +01:00
Peter Maydell c0f4af1719 target-arm: Don't handle c15_cpar changes via tb_flush()
At the moment we try to handle c15_cpar with the strategy of:
 * emit generated code which makes assumptions about its value
 * when the register value changes call tb_flush() to throw
   away the now-invalid generated code
This works because XScale CPUs are always uniprocessor, but
it's confusing because it suggests that the same approach can
be taken for other registers. It also means we do a tb_flush()
on CPU reset, which makes multithreaded linux-user binaries
even more likely to fail than would otherwise be the case.

Replace it with a combination of TB flags for the access
checks done on cp0/cp1 for the XScale and iwMMXt instructions,
plus a runtime check for cp2..cp13 coprocessor accesses.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1411056959-23070-1-git-send-email-peter.maydell@linaro.org
2014-09-29 18:48:48 +01:00
Peter Maydell 0eacea7060 target-arm: Implement handling of breakpoint firing
Implement handling of breakpoint event firing to correctly
inject the debug exception into the guest.

Since the breakpoint and watchpoint control register format is
very similar we adjust wp_matches() to also handle breakpoints
as well rather than using a separate function.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1410523465-13400-3-git-send-email-peter.maydell@linaro.org
2014-09-29 18:48:46 +01:00
Peter Maydell 46747d1508 target-arm: Implement setting guest breakpoints
This patch adds support for setting guest breakpoints
based on values the guest writes to the DBGBVR and DBGBCR
registers. (It doesn't include the code to handle when
these breakpoints fire, so has no guest-visible effect.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1410523465-13400-2-git-send-email-peter.maydell@linaro.org
2014-09-29 18:48:46 +01:00
Richard Henderson e8925712e6 target-arm: Use cpu_exec_interrupt qom hook
Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-15-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Peter Maydell fa439fc5d7 target-arm: Make *IS TLB maintenance ops affect all CPUs
The ARM architecture defines that the "IS" variants of TLB
maintenance operations must affect all TLBs in the Inner Shareable
domain, which for us means all CPUs. We were incorrectly implementing
these to only affect the current CPU, which meant that SMP TCG
operation was unstable.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1410274883-9578-3-git-send-email-peter.maydell@linaro.org
Cc: qemu-stable@nongnu.org
2014-09-12 14:06:50 +01:00
Peter Maydell 995939a650 target-arm: Push legacy wildcard TLB ops back into v6
When we implemented ARMv8 in QEMU we retained our legacy loose
wildcarded decoding of the TLB maintenance operations for v7
and earlier CPUs and provided the correct stricter decode for
v8. However the loose decode is in fact wrong for v7MP, because
it doesn't correctly implement the operations which must apply
to every CPU in the Inner Shareable domain.

Move the legacy wildcarding from the not_v8 reginfo array
into the not_v7 array, and move the strictly decoded operations
from the v8 reginfo to v7 or v7mp arrays as appropriate.

Cache and TLB lockdown legacy wildcarding remains in the
not_v8 array for the moment.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1410274883-9578-2-git-send-email-peter.maydell@linaro.org
Cc: qemu-stable@nongnu.org
2014-09-12 14:06:50 +01:00
Peter Maydell 5e8b12ffbb target-arm: Implement minimal DBGVCR, OSDLR_EL1, MDCCSR_EL0
Implement debug registers DBGVCR, OSDLR_EL1 and MDCCSR_EL0
(as dummy or limited-functionality). 32 bit Linux kernels will
access these at startup so they are required for breakpoints
and watchpoints to be supported.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:50 +01:00
Peter Maydell 17a9eb53a9 target-arm: Remove comment about MDSCR_EL1 being dummy implementation
MDSCR_EL1 has actual functionality now; remove the out of date
comment that claims it is a dummy implementation.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:49 +01:00
Peter Maydell 16a906fd6e target-arm: Set DBGDSCR.MOE for debug exceptions taken to AArch32
For debug exceptions taken to AArch32 we have to set the
DBGDSCR.MOE (Method Of Entry) bits; we can identify the
kind of debug exception from the information in
exception.syndrome.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:49 +01:00
Peter Maydell 3ff6fc9148 target-arm: Implement handling of fired watchpoints
Implement the ARM debug exception handler for dealing with
fired watchpoints.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:49 +01:00
Peter Maydell 73c5211ba9 target-arm: Move extended_addresses_enabled() to internals.h
Move the utility function extended_addresses_enabled() into
internals.h; we're going to need to call it from op_helper.c.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:49 +01:00
Peter Maydell 9ee98ce810 target-arm: Implement setting of watchpoints
Implement support for setting QEMU watchpoints based on the
values the guest writes to the ARM architected watchpoint
registers. (We do not yet report the firing of the watchpoints
to the guest, so they will just be ignored.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:49 +01:00
Martin Galvan 34bf774485 target-arm: Fix broken indentation in arm_cpu_reest()
Fix a single misindented line in arm_cpu_reset().

Signed-off-by: Martin Galvan <martin.galvan@tallertechnologies.com>
[PMM: split this out from the previous commit]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:48 +01:00
Martin Galvan 6e3cf5df01 target-arm: Fix resetting issues on ARMv7-M CPUs
When calling qemu_system_reset after startup on a Cortex-M
CPU, the initial values of PC, MSP and the Thumb bit weren't being set
correctly if the vector table was in ROM. In particular, since Thumb was 0, a
Usage Fault would arise immediately after trying to execute any instruction
on a Cortex-M.

Signed-off-by: Martin Galvan <martin.galvan@tallertechnologies.com>
Message-id: CAOKbPbaLt-LJsAKkQdOE0cs9Xx4OWrUfpDhATXPSdtuNw2xu_A@mail.gmail.com
[PMM: removed an incorrect comment]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:48 +01:00
Alistair Francis 0614601cec target-arm: Implement pmccfiltr_write function
This is the function that is called when writing to the
PMCCFILTR_EL0 register

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 73da3da6404855b17d5ae82975a32ff3a4dcae3d.1409025949.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-29 15:00:30 +01:00
Alistair Francis 942a155b20 target-arm: Remove old code and replace with new functions
Remove the old PMCCNTR code and replace it with calls to the new
pmccntr_sync() and arm_ccnt_enabled() functions.

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 693a6e437d915c2195fd3dc7303f384ca538b7bf.1409025949.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-29 15:00:30 +01:00
Alistair Francis ec7b4ce4c7 target-arm: Implement pmccntr_sync function
This is used to synchronise the PMCCNTR counter and swap its
state between enabled and disabled if required. It must always
be called twice, both before and after any logic that could
change the state of the PMCCNTR counter.

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 62811d4c0f7b1384f7aab62ea2fcfda3dcb0db50.1409025949.git.peter.crosthwaite@xilinx.com
[PMM: fixed minor typos in pmccntr_sync doc comment]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-29 15:00:29 +01:00
Alistair Francis 87124fdea4 target-arm: Add arm_ccnt_enabled function
Include a helper function to determine if the CCNT counter
is enabled.

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: e1a64f17a756e06c8bda8238ad4826d705049f7a.1409025949.git.peter.crosthwaite@xilinx.com
[ PC changes
  * Remove EL based checks
]
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-29 15:00:29 +01:00
Alistair Francis 8521466b39 target-arm: Implement PMCCNTR_EL0 and related registers
This patch adds support for the ARMv8 version of the PMCCNTR and
related registers. It also starts to implement the PMCCFILTR_EL0
register.

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: b5d1094764a5416363ee95216799b394ecd011e8.1409025949.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-29 15:00:29 +01:00
Peter Crosthwaite 421c7ebd93 arm: Implement PMCCNTR 32b read-modify-write
The register is now 64bit, however a 32 bit write to the register
should leave the higher bits unchanged. The open coded write handler
does not implement this, so we need to read-modify-write accordingly.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Alistair Francis <alistair23@gmail.com>
Message-id: ec350573424bb2adc1701c3b9278d26598e2f2d1.1409025949.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-29 15:00:29 +01:00
Alistair Francis c92c06872a target-arm: Make the ARM PMCCNTR register 64-bit
This makes the PMCCNTR register 64-bit to allow for the
64-bit ARMv8 version.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: 6c5bac5fd0ea54963b1fc0e7f9464909f2e19a73.1409025949.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-29 15:00:29 +01:00
Peter Maydell c379621451 target-arm: Correct Cortex-A57 ISAR5 and AA64ISAR0 ID register values
We implement the crypto extensions but were incorrectly reporting
ID register values for the Cortex-A57 which did not advertise
crypto. Use the correct values as described in the TRM.
With this fix Linux correctly detects presence of the crypto
features and advertises them in /proc/cpuinfo.

Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1408718660-7295-1-git-send-email-peter.maydell@linaro.org
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-29 15:00:28 +01:00
Peter Maydell ed1f13d607 target-arm: Fix regression that disabled VFP for ARMv5 CPUs
Commit 2c7ffc414 added support for honouring the CPACR coprocessor
access control register bits which may disable access to VFP
and Neon instructions. However it failed to account for the
fact that the CPACR is only present starting from the ARMv6
architecture version, so it accidentally disabled VFP completely
for ARMv5 CPUs like the ARM926. Linux would detect this as
"no VFP present" and probably fall back to its own emulation,
but other guest OSes might crash or misbehave.

This fixes bug LP:1359930.

Reported-by: Jakub Jermar <jakub@jermar.eu>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1408714940-7192-1-git-send-email-peter.maydell@linaro.org
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-29 15:00:28 +01:00
Peter Crosthwaite f7838b5290 arm: cortex-a9: Fix cache-line size and associativity
For A9, The cache associativity is 4 and the lines size is 32B.
Self identify in CCSIDR accordingly. Cache size remains at 16k.

QEMU doesn't emulate caches, but we should still report the correct
cache-line size to the guest. Some guests (like u-boot) complain if
the cache-line size mismatches a requested flush or invalidate
operation.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1de6bd40155a1d2f2e93e24b1b1d1d677a432641.1408346233.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-19 19:02:40 +01:00
Christoffer Dall 863714ba6c arm/virt: Use PSCI v0.2 function IDs in the DT when KVM uses PSCI v0.2
The current code supplies the PSCI v0.1 function IDs in the DT even when
KVM uses PSCI v0.2.

This will break guest kernels that only support PSCI v0.1 as they will
use the IDs provided in the DT.  Guest kernels with PSCI v0.2 support
are not affected by this patch, because they ignore the function IDs in
the device tree and rely on the architecture definition.

Define QEMU versions of the constants and check that they correspond to
the Linux defines on Linux build hosts.  After this patch, both guest
kernels with PSCI v0.1 support and guest kernels with PSCI v0.2 should
work.

Tested on TC2 for 32-bit and APM Mustang for 64-bit (aarch64 guest
only).  Both cases tested with 3.14 and linus/master and verified I
could bring up 2 cpus with both guest kernels.  Also tested 32-bit with
a 3.14 host kernel with only PSCI v0.1 and both guests booted here as
well.

Cc: qemu-stable@nongnu.org
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-19 19:02:25 +01:00
Christoffer Dall a65c9c17ce target-arm: Rename QEMU PSCI v0.1 definitions
The function IDs for PSCI v0.1 are exported by KVM and defined as
KVM_PSCI_FN_<something>.  To build using these defines in non-KVM code,
QEMU defines these IDs locally and check their correctness against the
KVM headers when those are available.

However, the naming scheme used for QEMU (almost) clashes with the PSCI
v0.2 definitions from Linux so to avoid unfortunate naming when we
introduce local PSCI v0.2 defines, rename the current local defines with
QEMU_ prependend and clearly identify the PSCI version as v0.1 in the
defines.

Cc: qemu-stable@nongnu.org
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-19 19:02:03 +01:00
Peter Maydell 0e5e8935bb target-arm: Implement MDSCR_EL1 as having state
Now that all the new code to support single-stepping is in
place, wire up the guest-visible MDSCR_EL1, so the guest
can enable single-stepping.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 50225ad0c1 target-arm: Implement ARMv8 single-stepping for AArch32 code
ARMv8 single-stepping requires the exception level that controls
the single-stepping to be in AArch64 execution state, but the
code being stepped may be in AArch64 or AArch32. Implement the
necessary support code for single-stepping AArch32 code.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 7ea47fe7be target-arm: Implement ARMv8 single-step handling for A64 code
Implement ARMv8 software single-step handling for A64 code:
correctly update the single-step state machine and generate
debug exceptions when stepping A64 code.

This patch has no behavioural change since MDSCR_EL1.SS can't
be set by the guest yet.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell cc9c1ed14e target-arm: A64: Avoid duplicate exit_tb(0) in non-linked goto_tb
If gen_goto_tb() decides not to link the two TBs, then the
fallback path generates unnecessary code:
 * if singlestep is enabled then we generate unreachable code
   after the gen_exception_internal(EXCP_DEBUG)
 * if singlestep is disabled then we will generate exit_tb(0)
   twice, once in gen_goto_tb() and once coming out of the
   main loop with is_jmp set to DISAS_JUMP

Correct these deficiencies by only emitting exit_tb() in the
non-singlestep case, in which case we can use DISAS_TB_JUMP
to suppress the main-loop exit_tb().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 3a2982038a target-arm: Set PSTATE.SS correctly on exception return from AArch64
Set the PSTATE.SS bit correctly on exception returns from AArch64,
as required by the debug single-step functionality.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 662cefb775 target-arm: Correctly handle PSTATE.SS when taking exception to AArch32
When an exception is taken to AArch32, we must clear the PSTATE.SS
bit for the exception handler, and must also ensure that the SS bit
is not set in the value saved to SPSR_<mode>. Achieve both of these
aims by clearing the bit in uncached_cpsr before saving it to the SPSR.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 4051e12c5d target-arm: Don't allow AArch32 to access RES0 CPSR bits
The CPSR has a new-in-v8 execution state bit (IL), and
also some state which has effects in AArch32 but appears
only in the SPSR format (SS) but is RES0 in the CPSR.

Add the IL bit to CPSR_EXEC, and enforce that guest direct
reads and writes to CPSR can't read or write the RES0
bits, so the guest can't get at the SS bit which we store
in uncached_cpsr. This includes not permitting exception
returns to copy reserved bits from an SPSR into CPSR.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 48eb3ae64b target-arm: Adjust debug ID registers per-CPU
Allow each CPU type to specify the value for the debug ID
registers, by putting them in the ARMCPU struct, and use
the resulting information to only expose the correct number
of watchpoint and breakpoint registers for the CPU.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 10aae1049f target-arm: Provide both 32 and 64 bit versions of debug registers
Bring the 32 bit and 64 bit views of the debug registers into
line by providing the same set of registers in both cases.
(This still isn't a complete set, but it is consistent.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 58a1d8ceab target-arm: Allow STATE_BOTH reginfo descriptions for more than cp14
Currently the STATE_BOTH shorthand for allowing a single reginfo struct
to define handling for both AArch32 and AArch64 views of a register
only permits this where the AArch32 view is in cp15. It turns out that
the debug registers in cp14 also have neatly lined up encodings;
allow these also to share reginfo structs by permitting a STATE_BOTH
reginfo to specify the .cp field (and continue to default to 15 if
it is not specified).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 503006983a target-arm: Collect up the debug cp register definitions
At the moment we have a mixed set of mostly dummy register
definitions for various debug related registers which have
been added piecemeal in order to get Linux kernels to boot.
In preparation for actually implementing debug support,
bring them all together into one place.

This commit doesn't change behaviour: we still expose
exactly the same registers and behaviour to the guest
in all configurations.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-08-19 19:02:03 +01:00
Peter Maydell 229a138d74 target-arm: Fix return address for A64 BRK instructions
When we take an exception resulting from a BRK instruction,
the architecture requires that the "preferred return address"
reported to the exception handler is the address of the BRK
itself, not the following instruction (like undefined
insns, and in contrast with SVC, HVC and SMC). Follow this,
rather than incorrectly reporting the address of the following
insn.

(We do get this correct for the A32/T32 BKPT insns.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Cc: qemu-stable@nongnu.org
2014-08-19 18:56:24 +01:00