Commit Graph

169 Commits

Author SHA1 Message Date
Richard Henderson
1d48474d8e disas: Remove unused flags arguments
Now that every target is using the disas_set_info hook,
the flags argument is unused.  Remove it.

Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-25 11:55:09 +02:00
Richard Henderson
1c2adb958f tcg: Initialize cpu_env generically
This is identical for each target.  So, move the initialization to
common code.  Move the variable itself out of tcg_ctx and name it
cpu_env to minimize changes within targets.

This also means we can remove tcg_global_reg_new_{ptr,i32,i64},
since there are no longer global-register temps created by targets.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
b1311c4acf tcg: define tcg_init_ctx and make tcg_ctx a pointer
Groundwork for supporting multiple TCG contexts.

The core of this patch is this change to tcg/tcg.h:

> -extern TCGContext tcg_ctx;
> +extern TCGContext tcg_init_ctx;
> +extern TCGContext *tcg_ctx;

Note that for now we set *tcg_ctx to whatever TCGContext is passed
to tcg_context_init -- in this case &tcg_init_ctx.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
2399d4e7ce target/arm: check CF_PARALLEL instead of parallel_cpus
Thereby decoupling the resulting translated code from the current state
of the system.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:41 -07:00
Emilio G. Cota
c5a49c63fa tcg: convert tb->cflags reads to tb_cflags(tb)
Convert all existing readers of tb->cflags to tb_cflags, so that we
use atomic_read and therefore avoid undefined behaviour in C11.

Note that the remaining setters/getters of the field are protected
by tb_lock, and therefore do not need conversion.

Luckily all readers access the field via 'tb->cflags' (so no foo.cflags,
bar->cflags in the code base), which makes the conversion easily
scriptable:

FILES=$(git grep 'tb->cflags' target include/exec/gen-icount.h \
	 accel/tcg/translator.c | cut -f1 -d':' | sort | uniq)

perl -pi -e 's/([^.>])tb->cflags/$1tb_cflags(tb)/g' $FILES
perl -pi -e 's/([a-z->.]*)(->|\.)tb->cflags/tb_cflags($1$2tb)/g' $FILES

Then manually fixed the few errors that checkpatch reported.

Compile-tested for all targets.

Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:41 -07:00
Peter Maydell
76eff04d16 target/arm: Implement SG instruction corner cases
The common situation of the SG instruction is that it is
executed from S&NSC memory by a CPU in NS state. That case
is handled by v7m_handle_execute_nsc(). However the instruction
also has defined behaviour in a couple of other cases:
 * SG instruction in NS memory (behaves as a NOP)
 * SG in S memory but CPU already secure (clears IT bits and
   does nothing else)
 * SG instruction in v8M without Security Extension (NOP)

These can be implemented in translate.c.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-10-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
dcf14dfb70 target/arm: Support some Thumb insns being always unconditional
A few Thumb instructions are always unconditional even inside an
IT block (as opposed to being UNPREDICTABLE if used inside an
IT block): BKPT, the v8M SG instruction, and the A profile
HLT (debug halt) instruction.

This means we need to suppress the jump-over-instruction-on-condfail
code generation (though the IT state still advances as usual and
subsequent insns in the IT block may be conditional).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-9-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
5b8d7289e9 target-arm: Simplify insn_crosses_page()
Recent changes have left insn_crosses_page() more complicated
than it needed to be:
 * it's only called from thumb_tr_translate_insn() so we know
   for certain that we're looking at a Thumb insn
 * the caller's check for dc->pc >= dc->next_page_start - 3
   means that dc->pc can't possibly be 4 aligned, so there's
   no need to check that (the check was partly there to ensure
   that we didn't treat an ARM insn as Thumb, I think)
 * we now have thumb_insn_is_16bit() which lets us do a precise
   check of the length of the next insn, rather than opencoding
   an inaccurate check

Simplify it down to just loading the first half of the insn
and calling thumb_insn_is_16bit() on it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-8-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
296e5a0a6c target/arm: Pull Thumb insn word loads up to top level
Refactor the Thumb decode to do the loads of the instruction words at
the top level rather than only loading the second half of a 32-bit
Thumb insn in the middle of the decode.

This is simple apart from the awkward case of Thumb1, where the
BL/BLX prefix and suffix instructions live in what in Thumb2 is the
32-bit insn space.  To handle these we decode enough to identify
whether we're looking at a prefix/suffix that we handle as a 16 bit
insn, or a prefix that we're going to merge with the following suffix
to consider as a 32 bit insn.  The translation of the 16 bit cases
then moves from disas_thumb2_insn() to disas_thumb_insn().

The refactoring has the benefit that we don't need to pass the
CPUARMState* down into the decoder code any more, but the major
reason for doing this is that some Thumb instructions must be always
unconditional regardless of the IT state bits, so we need to know the
whole insn before we emit the "skip this insn if the IT bits and cond
state tell us to" code.  (The always unconditional insns are BKPT,
HLT and SG; the last of these is 32 bits.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-7-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
6b8acf256d target-arm: Don't check for "Thumb2 or M profile" for not-Thumb1
The code which implements the Thumb1 split BL/BLX instructions
is guarded by a check on "not M or THUMB2". All we really need
to check here is "not THUMB2" (and we assume that elsewhere too,
eg in the ARCH(6T2) test that UNDEFs the Thumb2 insns).

This doesn't change behaviour because all M profile cores
have Thumb2 and so ARM_FEATURE_M implies ARM_FEATURE_THUMB2.
(v6M implements a very restricted subset of Thumb2, but we
can cross that bridge when we get to it with appropriate
feature bits.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-6-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
d02a8698d7 target/arm: Implement secure function return
Secure function return happens when a non-secure function has been
called using BLXNS and so has a particular magic LR value (either
0xfefffffe or 0xfeffffff). The function return via BX behaves
specially when the new PC value is this magic value, in the same
way that exception returns are handled.

Adjust our BX excret guards so that they recognize the function
return magic number as well, and perform the function-return
unstacking in do_v7m_exception_exit().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-5-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
3e3fa230e3 target/arm: Implement BLXNS
Implement the BLXNS instruction, which allows secure code to
call non-secure code.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-4-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
b9f587d62c target/arm: Add M profile secure MMU index values to get_a32_user_mem_index()
Add the M profile secure MMU index values to the switch in
get_a32_user_mem_index() so that LDRT/STRT work correctly
rather than asserting at translate time.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-2-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Emilio G. Cota
7f11636dbe tcg: remove addr argument from lookup_tb_ptr
It is unlikely that we will ever want to call this helper passing
an argument other than the current PC. So just remove the argument,
and use the pc we already get from cpu_get_tb_cpu_state.

This change paves the way to having a common "tb_lookup" function.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 07:37:10 -07:00
Peter Maydell
ef475b5dd1 target-arm:
* cleanups converting to DEFINE_PROP_LINK
  * allwinner-a10: mark as not user-creatable
  * initial patches working towards ARMv8M support
  * implement generating aborts on memory transaction failures
  * make BXJ behave correctly (ie not UNDEF) on ARMv6-and-later
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABCAAGBQJZsUjvAAoJEDwlJe0UNgzey10P+wf1TRxRMGnoDftimLyPt9Pt
 cXYSP1KKF4qn618ZSJHPHJasWEx2obAP8JrrA8qLz0quWpWlXZ40bhgxKX9iKb2l
 4jrt/DjfTH7RWMRs94lOb0ZOtMokLfjHMSBhP31xR4Lgia0HdlmwqUPLr2T10ffE
 B9BKvPbXcee9Ss7osDqQr3OMUtSMjuc3G3z3WaySwG80od9MB8mblnMU0h9gZEeT
 6csGRHU8rfOkv9ZzrSJRWBuhmxC0Mrg3lB3iZffupFnI//q+PZfW2+ojAyn+pATu
 3YgHjgfgw4P5N2iGlg8c4y6mrig0fQNHWIXWFk7zWp7kWCdXnq5doFpJmi+CfMlE
 yQqMYzuy2Bd9n2fAB036nvb1LBHEKFYfKxqPoeJzuB9wEcXjmnbwuJ+iAKo/DP94
 9wE/cPNKySFmZJFEz+byAZvnEp0ynpQtDoCnaIJPbx6ytkKfL9xXX78+mmlTn8hj
 55NyH2aaEXpuxJKkld1pP2O+r/amFJ603rujSEaK0Or2YGcE1fit+YZSSh1glt25
 b3vEKn1ydWV4udRjBIEd0l/PIhGenILXC3bDONiWqEIPaMVeOxjhl+lvEHmELOjd
 t+o4ntQfU94Z6eDXPhx/bXqIZi9qtDbMZosojWL6wMAIMEiuXlB/a9vhcs9uBnRJ
 M0PiR5jVpZgDfLipV/8A
 =URgX
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20170907' into staging

target-arm:
 * cleanups converting to DEFINE_PROP_LINK
 * allwinner-a10: mark as not user-creatable
 * initial patches working towards ARMv8M support
 * implement generating aborts on memory transaction failures
 * make BXJ behave correctly (ie not UNDEF) on ARMv6-and-later

# gpg: Signature made Thu 07 Sep 2017 14:26:07 BST
# gpg:                using RSA key 0x3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20170907: (31 commits)
  target/arm: Add Jazelle feature
  target/arm: Implement new do_transaction_failed hook
  hw/arm: Set ignore_memory_transaction_failures for most ARM boards
  boards.h: Define new flag ignore_memory_transaction_failures
  target/arm: Implement BXNS, and banked stack pointers
  target/arm: Move regime_is_secure() to target/arm/internals.h
  target/arm: Make CFSR register banked for v8M
  target/arm: Make MMFAR banked for v8M
  target/arm: Make CCR register banked for v8M
  target/arm: Make MPU_CTRL register banked for v8M
  target/arm: Make MPU_RNR register banked for v8M
  target/arm: Make MPU_RBAR, MPU_RLAR banked for v8M
  target/arm: Make MPU_MAIR0, MPU_MAIR1 registers banked for v8M
  target/arm: Make VTOR register banked for v8M
  nvic: Add NS alias SCS region
  target/arm: Make CONTROL register banked for v8M
  target/arm: Make FAULTMASK register banked for v8M
  target/arm: Make PRIMASK register banked for v8M
  target/arm: Make BASEPRI register banked for v8M
  target/arm: Add MMU indexes for secure v8M
  ...

# Conflicts:
#	target/arm/translate.c
2017-09-07 16:46:15 +01:00
Portia Stephens
c99a55d38d target/arm: Add Jazelle feature
This adds a feature bit indicating support of the (trivial) Jazelle
implementation if ARM_FEATURE_V6 is set or if the processor is arm926
or arm1026.  This fixes the issue that any BXJ instruction will
result in an illegal_op.  BXJ instructions will now check if the
architecture supports ARM_FEATURE_JAZELLE.

Signed-off-by: Portia Stephens <portia.stephens@xilinx.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: 20170905211232.11092-1-portia.stephens@xilinx.com
[PMM: edited commit message and comment text a bit]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-09-07 13:54:55 +01:00
Peter Maydell
fb602cb726 target/arm: Implement BXNS, and banked stack pointers
Implement the BXNS v8M instruction, which is like BX but will do a
jump-and-switch-to-NonSecure if the branch target address has bit 0
clear.

This is the first piece of code which implements "switch to the
other security state", so the commit also includes the code to
switch the stack pointers around, which is the only complicated
part of switching security state.

BLXNS is more complicated than just "BXNS but set the link register",
so we leave it for a separate commit.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-21-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:54 +01:00
Peter Maydell
8bfc26ea30 target/arm: Make CONTROL register banked for v8M
Make the CONTROL register banked if v8M security extensions are enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-10-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:53 +01:00
Peter Maydell
1e577cc7cf target/arm: Add state field, feature bit and migration for v8M secure state
As the first step in implementing ARM v8M's security extension:
 * add a new feature bit ARM_FEATURE_M_SECURITY
 * add the CPU state field that indicates whether the CPU is
   currently in the secure state
 * add a migration subsection for this new state
   (we will add the Secure copies of banked register state
   to this subsection in later patches)
 * add a #define for the one new-in-v8M exception type
 * make the CPU debug log print S/NS status

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-4-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:52 +01:00
Richard Henderson
d0264d86b0 target/arm: Perform per-insn cross-page check only for Thumb
ARM is a fixed-length ISA and we can compute the page crossing
condition exactly once during init_disas_context.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Richard Henderson
722ef0a562 target/arm: Split out thumb_tr_translate_insn
We need not check for ARM vs Thumb state in order to dispatch
disassembly of every instruction.

Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Richard Henderson
f7708456aa target/arm: Move ss check to init_disas_context
We can check for single-step just once.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Lluís Vilanova
2316922420 target/arm: [tcg] Port to generic translation framework
Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002631325.22386.10348327185029496649.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Lluís Vilanova
4013f7fc81 target/arm: [tcg] Port to disas_log
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002582711.22386.191527630537864599.stgit@frigg.lan>
[rth: Move tb->size computation and use that result.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Lluís Vilanova
70d3c035ae target/arm: [tcg] Port to tb_stop
Incrementally paves the way towards using the generic instruction translation
loop.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002534291.22386.13499916738708680298.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Lluís Vilanova
13189a9080 target/arm: [tcg] Port to translate_insn
Incrementally paves the way towards using the generic instruction translation
loop.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002485863.22386.13949856269576226529.stgit@frigg.lan>
[rth: Adjust for translate_insn interface change.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
a68956ad7f target/arm: [tcg,a64] Port to insn_start
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002413187.22386.156315485813606121.stgit@frigg.lan>
[rth: Use DISAS_TOO_MANY for "execute only one more" after bp.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
f62bd897e6 target/arm: [tcg] Port to insn_start
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002388959.22386.12439646324427589940.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
b14768544f target/arm: [tcg] Port to tb_start
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002364681.22386.1701754996184325808.stgit@frigg.lan>
[rth: Adjust for tb_start interface change.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
1d8a553523 target/arm: [tcg] Port to init_disas_context
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002316201.22386.12115078843605656029.stgit@frigg.lan>
[rth: Adjust for max_insns interface change.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
dcba3a8d44 target/arm: [tcg] Port to DisasContextBase
Incrementally paves the way towards using the generic
instruction translation loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002291931.22386.11441154993010495674.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Richard Henderson
3805c2eba8 target/arm: Delay check for magic kernel page
There's nothing magic about the exception that we generate in order
to execute the magic kernel page.  We can and should allow gdb to
set a breakpoint at this location.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
77fc6f5e28 target: [tcg] Use a generic enum for DISAS_ values
Used later. An enum makes expected values explicit and
bounds the value space of switches.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-Id: <150002049746.22386.2316077281615710615.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Richard Henderson
a0c231e651 target/arm: Use DISAS_NORETURN
Fold DISAS_EXC and DISAS_TB_JUMP into DISAS_NORETURN.

In both cases all following code is dead.  In the first
case because we have exited the TB via exception; in the
second case because we have exited the TB via goto_tb
and its associated machinery.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Peter Maydell
5b906f3589 target/arm: Make arm_cpu_dump_state() handle the M-profile XPSR
Make the arm_cpu_dump_state() debug logging handle the M-profile XPSR
rather than assuming it's an A-profile CPSR.  On M profile the PSR
line of a register dump will now look like this:

XPSR=41000000 -Z-- T priv-thread

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1501692241-23310-12-git-send-email-peter.maydell@linaro.org
2017-09-04 15:21:52 +01:00
Peter Maydell
ebfe27c593 target/arm: Tighten up Thumb decode where new v8M insns will be
Tighten up the T32 decoder in the places where new v8M instructions
will be:
 * TT/TTT/TTA/TTAT are in what was nominally LDREX/STREX r15, ...
   which is UNPREDICTABLE:
   make the UNPREDICTABLE behaviour be to UNDEF
 * BXNS/BLXNS are distinguished from BX/BLX via the low 3 bits,
   which in previous architectural versions are SBZ:
   enforce the SBZ via UNDEF rather than ignoring it, and move
   the "ARCH(5)" UNDEF case up so we don't leak a TCG temporary
 * SG is in the encoding which would be LDRD/STRD with rn = r15;
   this is UNPREDICTABLE and we currently UNDEF:
   move this check further up the code so that we don't leak
   TCG temporaries in the UNDEF case and have a better place
   to put the SG decode.

This means that if a v8M binary is accidentally run on v7M
or if a test case hits something that we haven't implemented
yet the behaviour will be obvious (UNDEF) rather than obscure
(plough on treating it as a different instruction).

In the process, add some comments about the instruction patterns
at these points in the decode. Our Thumb and ARM decoders are
very difficult to understand currently, but gradually adding
comments like this should help to clarify what exactly has
been decoded when.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1501692241-23310-5-git-send-email-peter.maydell@linaro.org
2017-09-04 15:21:51 +01:00
Lluís Vilanova
9c489ea6be tcg: Pass generic CPUState to gen_intermediate_code()
Needed to implement a target-agnostic gen_intermediate_code()
in the future.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002025498.22386.18051908483085660588.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-07-19 14:45:16 -07:00
Aurelien Jarno
68cedf733a target/arm: optimize aarch32 rev16
Use the same mask to avoid having to load two different constants, as
suggested by Richard Henderson.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170516230159.4195-2-aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-07-19 14:45:15 -07:00
Alex Bennée
b29fd33db5 target/arm: use DISAS_EXIT for eret handling
Previously DISAS_JUMP did ensure this but with the optimisation of
8a6b28c7 (optimize indirect branches) we might not leave the loop.
This means if any pending interrupts are cleared by changing IRQ flags
we might never get around to servicing them. You usually notice this
by seeing the lookup_tb_ptr() helper gainfully chaining TBs together
while cpu->interrupt_request remains high and the exit_request has not
been set.

This breaks amongst other things the OPTEE test suite which executes
an eret from the secure world after a non-secure world IRQ has gone
pending which then never gets serviced.

Instead of using the previously implied semantics of DISAS_JUMP we use
DISAS_EXIT which will always exit the run-loop.

CC: Etienne Carriere <etienne.carriere@linaro.org>
CC: Joakim Bech <joakim.bech@linaro.org>
CC: Jaroslaw Pelczar <j.pelczar@samsung.com>
CC: Peter Maydell <peter.maydell@linaro.org>
CC: Emilio G. Cota <cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 20170713141928.25419-7-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-17 13:36:07 +01:00
Alex Bennée
0b609cc128 target/arm: use gen_goto_tb for ISB handling
While an ISB will ensure any raised IRQs happen on the next
instruction it doesn't cause any to get raised by itself. We can
therefore use a simple tb exit for ISB instructions and rely on the
exit_request check at the top of each TB to deal with exiting if
needed.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 20170713141928.25419-6-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-17 13:36:07 +01:00
Alex Bennée
4cae8f56fb target/arm/translate: ensure gen_goto_tb sets exit flags
As the gen_goto_tb function can do both static and dynamic jumps it
should also set the is_jmp field. This matches the behaviour of the
a64 code.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 20170713141928.25419-5-alex.bennee@linaro.org
[tweak to multiline comment formatting]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-17 13:36:07 +01:00
Alex Bennée
e8d5230221 target/arm/translate: make DISAS_UPDATE match declared semantics
DISAS_UPDATE should be used when the wider CPU state other than just
the PC has been updated and we should therefore exit the TCG runtime
and return to the main execution loop rather assuming DISAS_JUMP would
do that.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 20170713141928.25419-3-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-17 13:36:07 +01:00
Emilio G. Cota
8a6b28c7b5 target/arm: optimize indirect branches
Speed up indirect branches by jumping to the target if it is valid.

Softmmu measurements (see later commit for user-mode results):

Note: baseline (i.e. speedup == 1x) is QEMU v2.9.0.

- Impact on Boot time

| setup  | ARM debian jessie boot+shutdown time | stddev |
|--------+--------------------------------------+--------|
| v2.9.0 |                                 8.84 |   0.07 |
| +cross |                                 8.85 |   0.03 |
| +jr    |                                 8.83 |   0.06 |

-                            NBench, arm-softmmu (debian jessie guest). Host: Intel i7-4790K @ 4.00GHz

  1.3x +-+-------------------------------------------------------------------------------------------------------------+-+
       |                                                                                                                 |
       |   cross                                                          ####                                           |
 1.25x +cross+jr..........................................................#++#.........................................+-+
       |                                                        ####      #  #                                           |
       |                                                     +++#  #      #  #                                           |
       |                                      +++            ****  #      #  #                                           |
  1.2x +-+...................................####............*..*..#......#..#.........................................+-+
       |                                  ****  #            *  *  #      #  #     ####                                  |
       |                                  *  *  #            *  *  #      #  #     #  #                                  |
 1.15x +-+................................*..*..#............*..*..#......#..#.....#..#................................+-+
       |                                  *  *  #            *  *  #      #  #     #  #                                  |
       |                                  *  *  #      ####  *  *  #      #  #     #  #                                  |
       |                                  *  *  #      #  #  *  *  #      #  #     #  #                         ####     |
  1.1x +-+................................*..*..#......#..#..*..*..#......#..#.....#..#.........................#..#...+-+
       |                                  *  *  #      #  #  *  *  #      #  #     #  #                         #  #     |
       |                                  *  *  #      #  #  *  *  #      #  #     #  #                         #  #     |
 1.05x +-+..........................####..*..*..#......#..#..*..*..#......#..#.....#..#......+++............*****..#...+-+
       |                        *****  #  *  *  #      #  #  *  *  #  *****  #     #  #   +++ |    ****###  *   *  #     |
       |                        *+++*  #  *  *  #      #  #  *  *  #  *+++*  #  ****  #  *****###  *  *  #  *   *  #     |
       |     *****###  +++####  *   *  #  *  *  #  *****  #  *  *  #  *   *  #  *  *  #  * | *++#  *  *  #  *   *  #     |
    1x +-++-+*+++*-+#++****++#++*+-+*++#+-*++*++#-+*+++*-+#++*++*++#++*+-+*++#+-*++*++#-+*+++*-+#++*++*++#++*+-+*++#+-++-+
       |     *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #     |
       |     *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #     |
 0.95x +-+---*****###--****###--*****###--****###--*****###--****###--*****###--****###--*****###--****###--*****###---+-+
       ASSIGNMENT BITFIELD   FOURFP EMULATION   HUFFMAN   LU DECOMPOSITIONEURAL NNUMERIC SOSTRING SORT     hmean
  png: http://imgur.com/eOLmZNR

NB. 'cross' represents the previous commit.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1493263764-18657-8-git-send-email-cota@braap.org>
[rth: Replace gen_jr global variable with DISAS_EXIT state.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-06-05 09:25:42 -07:00
Emilio G. Cota
7ad55b4ffd target/arm: optimize cross-page direct jumps in softmmu
Instead of unconditionally exiting to the exec loop, use the
lookup_and_goto_ptr helper to jump to the target if it is valid.

Perf impact: see next commit's log.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1493263764-18657-7-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-06-05 09:25:42 -07:00
Peter Maydell
3bef701256 arm: Implement HFNMIENA support for M profile MPU
Implement HFNMIENA support for the M profile MPU. This bit controls
whether the MPU is treated as enabled when executing at execution
priorities of less than zero (in NMI, HardFault or with the FAULTMASK
bit set).

Doing this requires us to use a different MMU index for "running
at execution priority < 0", because we will have different
access permissions for that case versus the normal case.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1493122030-32191-14-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:49 +01:00
Peter Maydell
e7b921c2d9 arm: Use different ARMMMUIdx values for M profile
Make M profile use completely separate ARMMMUIdx values from
those that A profile CPUs use. This is a prelude to adding
support for the MPU and for v8M, which together will require
6 MMU indexes which don't map cleanly onto the A profile
uses:
 non secure User
 non secure Privileged
 non secure Privileged, execution priority < 0
 secure User
 secure Privileged
 secure Privileged, execution priority < 0

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1493122030-32191-4-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:47 +01:00
Peter Maydell
8bd5c82030 arm: Add support for M profile CPUs having different MMU index semantics
The M profile CPU's MPU has an awkward corner case which we
would like to implement with a different MMU index.

We can avoid having to bump the number of MMU modes ARM
uses, because some of our existing MMU indexes are only
used by non-M-profile CPUs, so we can borrow one.
To avoid that getting too confusing, clean up the code
to try to keep the two meanings of the index separate.

Instead of ARMMMUIdx enum values being identical to core QEMU
MMU index values, they are now the core index values with some
high bits set. Any particular CPU always uses the same high
bits (so eventually A profile cores and M profile cores will
use different bits). New functions arm_to_core_mmu_idx()
and core_to_arm_mmu_idx() convert between the two.

In general core index values are stored in 'int' types, and
ARM values are stored in ARMMMUIdx types.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1493122030-32191-3-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:47 +01:00
Peter Maydell
f4e8e4edda arm: Remove workarounds for old M-profile exception return implementation
Now that we've rewritten M-profile exception return so that the magic
PC values are not visible to other parts of QEMU, we can delete the
special casing of them elsewhere.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1491844419-12485-10-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
3bb8a96f53 arm: Implement M profile exception return properly
On M profile, return from exceptions happen when code in Handler mode
executes one of the following function call return instructions:
 * POP or LDM which loads the PC
 * LDR to PC
 * BX register
and the new PC value is 0xFFxxxxxx.

QEMU tries to implement this by not treating the instruction
specially but then catching the attempt to execute from the magic
address value.  This is not ideal, because:
 * there are guest visible differences from the architecturally
   specified behaviour (for instance jumping to 0xFFxxxxxx via a
   different instruction should not cause an exception return but it
   will in the QEMU implementation)
 * we have to account for it in various places (like refusing to take
   an interrupt if the PC is at a magic value, and making sure that
   the MPU doesn't deny execution at the magic value addresses)

Drop these hacks, and instead implement exception return the way the
architecture specifies -- by having the relevant instructions check
for the magic value and raise the 'do an exception return' QEMU
internal exception immediately.

The effect on the generated code is minor:

 bx lr, old code (and new code for Thread mode):
  TCG:
   mov_i32 tmp5,r14
   movi_i32 tmp6,$0xfffffffffffffffe
   and_i32 pc,tmp5,tmp6
   movi_i32 tmp6,$0x1
   and_i32 tmp5,tmp5,tmp6
   st_i32 tmp5,env,$0x218
   exit_tb $0x0
   set_label $L0
   exit_tb $0x7f2aabd61993
  x86_64 generated code:
   0x7f2aabe87019:  mov    %ebx,%ebp
   0x7f2aabe8701b:  and    $0xfffffffffffffffe,%ebp
   0x7f2aabe8701e:  mov    %ebp,0x3c(%r14)
   0x7f2aabe87022:  and    $0x1,%ebx
   0x7f2aabe87025:  mov    %ebx,0x218(%r14)
   0x7f2aabe8702c:  xor    %eax,%eax
   0x7f2aabe8702e:  jmpq   0x7f2aabe7c016

 bx lr, new code when in Handler mode:
  TCG:
   mov_i32 tmp5,r14
   movi_i32 tmp6,$0xfffffffffffffffe
   and_i32 pc,tmp5,tmp6
   movi_i32 tmp6,$0x1
   and_i32 tmp5,tmp5,tmp6
   st_i32 tmp5,env,$0x218
   movi_i32 tmp5,$0xffffffffff000000
   brcond_i32 pc,tmp5,geu,$L1
   exit_tb $0x0
   set_label $L1
   movi_i32 tmp5,$0x8
   call exception_internal,$0x0,$0,env,tmp5
  x86_64 generated code:
   0x7fe8fa1264e3:  mov    %ebp,%ebx
   0x7fe8fa1264e5:  and    $0xfffffffffffffffe,%ebx
   0x7fe8fa1264e8:  mov    %ebx,0x3c(%r14)
   0x7fe8fa1264ec:  and    $0x1,%ebp
   0x7fe8fa1264ef:  mov    %ebp,0x218(%r14)
   0x7fe8fa1264f6:  cmp    $0xff000000,%ebx
   0x7fe8fa1264fc:  jae    0x7fe8fa126509
   0x7fe8fa126502:  xor    %eax,%eax
   0x7fe8fa126504:  jmpq   0x7fe8fa122016
   0x7fe8fa126509:  mov    %r14,%rdi
   0x7fe8fa12650c:  mov    $0x8,%esi
   0x7fe8fa126511:  mov    $0x56095dbeccf5,%r10
   0x7fe8fa12651b:  callq  *%r10

which is a difference of one cmp/branch-not-taken. This will
be lost in the noise of having to exit generated code and
look up the next TB anyway.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1491844419-12485-9-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
064c379c99 arm: Track M profile handler mode state in TB flags
For M profile exception-return handling we'd like to generate different
code for some instructions depending on whether we are in Handler
mode or Thread mode. This isn't the same as "are we privileged
or user", so we need an extra bit in the TB flags to distinguish.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1491844419-12485-8-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
b636649f5a arm: Abstract out "are we singlestepping" test to utility function
We now test for "are we singlestepping" in several places and
it's not a trivial check because we need to care about both
architectural singlestep and QEMU gdbstub singlestep. We're
also about to add another place that needs to make this check,
so pull the condition out into a function.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1491844419-12485-7-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
f021b2c462 arm: Move condition-failed codepath generation out of if()
Move the code to generate the "condition failed" instruction
codepath out of the if (singlestepping) {} else {}. This
will allow adding support for handling a new is_jmp type
which can't be neatly split into "singlestepping case"
versus "not singlestepping case".

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1491844419-12485-6-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
4d5e8c969a arm: Move gen_set_condexec() and gen_set_pc_im() up in the file
Move the utility routines gen_set_condexec() and gen_set_pc_im()
up in the file, as we will want to use them from a function
placed earlier in the file than their current location.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1491844419-12485-5-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
5425415ebb arm: Factor out "generate right kind of step exception"
We currently have two places that do:
            if (dc->ss_active) {
                gen_step_complete_exception(dc);
            } else {
                gen_exception_internal(EXCP_DEBUG);
            }

Factor this out into its own function, as we're about to add
a third place that needs the same logic.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1491844419-12485-4-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
bedb8a6b09 arm: Thumb shift operations should not permit interworking branches
In Thumb mode, the only instructions which can cause an interworking
branch by writing the PC are BLX, BX, BXJ, LDR, POP and LDM. Unlike
ARM mode, data processing instructions which target the PC do not
cause interworking branches.

When we added support for doing interworking branches on writes to
PC from data processing instructions in commit 21aeb3430c, we
accidentally changed a Thumb instruction to have interworking
branch behaviour for writes to PC. (MOV, MOVS register-shifted
register, encoding T2; this is the standard encoding for
LSL/LSR/ASR/ROR (register).)

For this encoding, behaviour with Rd == R15 is specified as
UNPREDICTABLE, so allowing an interworking branch is within
spec, but it's confusing and differs from our handling of this
class of UNPREDICTABLE for other Thumb ALU operations. Make
it perform a simple (non-interworking) branch like the others.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1491844419-12485-3-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
9d7c59c84d arm: Don't implement BXJ on M-profile CPUs
For M-profile CPUs, the BXJ instruction does not exist at all, and
the encoding should always UNDEF. We were accidentally implementing
it to behave like A-profile BXJ; correct the error.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1491844419-12485-2-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
b28b3377d7 arm: Fix APSR writes via M profile MSR
Our implementation of writes to the APSR for M-profile via the MSR
instruction was badly broken.

First and worst, we had the sense wrong on the test of bit 2 of the
SYSm field -- this is supposed to request an APSR write if bit 2 is 0
but we were doing it if bit 2 was 1.  This bug was introduced in
commit 58117c9bb4, so hasn't been in a QEMU release.

Secondly, the choice of exactly which parts of APSR should be written
is defined by bits in the 'mask' field.  We were not passing these
through from instruction decode, making it impossible to check them
in the helper.

Pass the mask bits through from the instruction decode to the helper
function and process them appropriately; fix the wrong sense of the
SYSm bit 2 check.

Invalid mask values and invalid combinations of mask and register
number are UNPREDICTABLE; we choose to treat them as if the mask
values were valid.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1487616072-9226-5-git-send-email-peter.maydell@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-03-20 12:41:44 +00:00
Peter Maydell
3d54026fb0 arm: Enforce should-be-1 bits in MRS decoding
The MRS instruction requires that bits [19..16] are all 1s, and for
A/R profile also that bits [7..0] are all 0s.  At this point in the
decode tree we have checked all of the rest of the instruction but
were allowing these to be any value.  If these bits are not set then
the result is architecturally UNPREDICTABLE, but choosing to UNDEF is
more helpful to the user and avoids unexpected odd behaviour if the
encodings are used for some purpose in future architecture versions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1487616072-9226-4-git-send-email-peter.maydell@linaro.org
2017-03-20 12:41:44 +00:00
Peter Maydell
43ac657423 arm: Don't decode MRS(banked) or MSR(banked) for M profile
M profile doesn't have the MSR(banked) and MRS(banked) instructions
and uses the encodings for different kinds of M-profile MRS/MSR.
Guard the relevant bits of the decode logic to make sure we don't
accidentally fall into them by accident on M-profile.

(The bit being checked for this (bit 5) is part of the SYSm field on
M-profile, but since no currently allocated system registers have
encodings with bit 5 of SYSm set, this hasn't been a problem in
practice.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1487616072-9226-3-git-send-email-peter.maydell@linaro.org
2017-03-20 12:41:44 +00:00
Peter Maydell
001b3cab51 arm: HVC and SMC encodings don't exist for M profile
M profile doesn't have the HVC or SMC encodings, so make them always
UNDEF rather than generating calls to helper functions that assume
A/R profile.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1487616072-9226-2-git-send-email-peter.maydell@linaro.org
2017-03-20 12:41:44 +00:00
Peter Maydell
e13886e3a7 armv7m: Raise correct kind of UsageFault for attempts to execute ARM code
M profile doesn't implement ARM, and the architecturally required
behaviour for attempts to execute with the Thumb bit clear is to
generate a UsageFault with the CFSR INVSTATE bit set.  We were
incorrectly implementing this as generating an UNDEFINSTR UsageFault;
fix this.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:19 +00:00
Alex Bennée
c22edfebff target-arm: don't generate WFE/YIELD calls for MTTCG
The WFE and YIELD instructions are really only hints and in TCG's case
they were useful to move the scheduling on from one vCPU to the next. In
the parallel context (MTTCG) this just causes an unnecessary cpu_exit
and contention of the BQL.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-24 10:32:46 +00:00
Peter Maydell
9bb6558a21 target/arm: A32, T32: Create Instruction Syndromes for Data Aborts
Add support for generating the ISS (Instruction Specific Syndrome)
for Data Abort exceptions taken from AArch32. These syndromes are
used by hypervisors for example to trap and emulate memory accesses.

This is the equivalent for AArch32 guests of the work done for AArch64
guests in commit aaa1f954d4.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2017-02-07 18:30:00 +00:00
Peter Maydell
63f26fcfda target/arm: Abstract out pbit/wbit tests in ARM ldr/str decode
In the ARM ldr/str decode path, rather than directly testing
"insn & (1 << 21)" and "insn & (1 << 24)", abstract these
bits out into wbit and pbit local flags. (We will want to
do more tests against them to determine whether we need to
provide syndrome information.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2017-02-07 18:29:59 +00:00
Peter Maydell
7517748e3f armv7m: Report no-coprocessor faults correctly
For v7M attempts to access a nonexistent coprocessor are reported
differently from plain undefined instructions (as UsageFaults of type
NOCP rather than type UNDEFINSTR).  Split them out into a new
EXCP_NOCP so we can report the FSR value correctly.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1485285380-10565-8-git-send-email-peter.maydell@linaro.org
2017-01-27 15:29:08 +00:00
Michael Davidsaver
542b3478a0 armv7m: Replace armv7m.hack with unassigned_access handler
For v7m we need to catch attempts to execute from special
addresses at 0xfffffff0 and above. Previously we did this
with the aid of a hacky special purpose lump of memory
in the address space and a check in translate.c for whether
we were translating code at those addresses.

We can implement this more cleanly using a CPU
unassigned access handler which throws the exception
if the unassigned access is for one of the special addresses.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1484937883-1068-3-git-send-email-peter.maydell@linaro.org
[PMM:
 * drop the deletion of the "don't interrupt if PC is magic"
   code in arm_v7m_cpu_exec_interrupt() -- this is still
   required
 * don't generate an exception for unassigned accesses
   which aren't to the magic address -- although doing
   this is in theory correct in practice it will break
   currently working guests which rely on the RAZ/WI
   behaviour when they touch devices which we haven't
   modelled.
 * trigger EXCP_EXCEPTION_EXIT on is_exec, not !is_write
]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-01-27 15:20:21 +00:00
Richard Henderson
7539a012f6 target-arm: Use clz opcode
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10 08:06:11 -08:00
Richard Henderson
59a71b4c5b target-arm: Use new deposit and extract ops
Use the new primitives for UBFX and SBFX.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10 08:06:10 -08:00
Thomas Huth
fcf5ef2ab5 Move target-* CPU file into a target/ folder
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.

Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [cris&microblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2016-12-20 21:52:12 +01:00