Commit Graph

108 Commits

Author SHA1 Message Date
Peter Maydell
a65afaae0f x86 and machine queue, 2017-06-05
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Merge remote-tracking branch 'remotes/ehabkost/tags/x86-and-machine-pull-request' into staging

x86 and machine queue, 2017-06-05

# gpg: Signature made Mon 05 Jun 2017 19:58:01 BST
# gpg:                using RSA key 0x2807936F984DC5A6
# gpg: Good signature from "Eduardo Habkost <ehabkost@redhat.com>"
# Primary key fingerprint: 5A32 2FD5 ABC4 D3DB ACCF  D1AA 2807 936F 984D C5A6

* remotes/ehabkost/tags/x86-and-machine-pull-request:
  scripts: Test script to look for -device crashes
  qemu.py: Add QEMUMachine.exitcode() method
  qemu.py: Don't set _popen=None on error/shutdown
  spapr: cleanup spapr_fixup_cpu_numa_dt() usage
  numa: move numa_node from CPUState into target specific classes
  numa: make hmp 'info numa' fetch numa nodes from qmp_query_cpus() result
  numa: make sure that all cpus have has_node_id set if numa is enabled
  numa: move default mapping init to machine
  numa: consolidate cpu_preplug fixups/checks for pc/arm/spapr
  pc: Use "min-[x]level" on compat_props

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-06-06 10:00:34 +01:00
Igor Mammedov
15f8b14228 numa: move numa_node from CPUState into target specific classes
Move vcpu's associated numa_node field out of generic CPUState
into inherited classes that actually care about cpu<->numa mapping,
i.e: ARMCPU, PowerPCCPU, X86CPU.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <1496161442-96665-6-git-send-email-imammedo@redhat.com>
[ehabkost: s/CPU is belonging to/CPU belongs to/ on comments]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2017-06-05 14:59:09 -03:00
Emilio G. Cota
e75449a346 target/aarch64: optimize indirect branches
Measurements:

[Baseline performance is that before applying this and the previous commit]

-                                    NBench, aarch64-softmmu. Host: Intel i7-4790K @ 4.00GHz

 1.7x +-+--------------------------------------------------------------------------------------------------------------+-+
      |                                                                                                                  |
      |   cross                                                                                                          |
 1.6x +cross+jr.................................................####...................................................+-+
      |                                                         #++#                                                     |
      |                                                         #  #                                                     |
 1.5x +-+...................................................*****..#...................................................+-+
      |                                                     *+++*  #                                                     |
      |                                                     *   *  #                                                     |
 1.4x +-+...................................................*...*..#...................................................+-+
      |                                                     *   *  #                                                     |
      |                                     #####           *   *  #                                                     |
 1.3x +-+................................****+++#...........*...*..#...................................................+-+
      |                                  *++*   #           *   *  #                                                     |
      |                                  *  *   #           *   *  #                                                     |
 1.2x +-+................................*..*...#...........*...*..#...................................................+-+
      |                                  *  *   #           *   *  #                                                     |
      |                            ####  *  *   #           *   *  #                                                     |
 1.1x +-+.......................+++#..#..*..*...#...........*...*..#...................................................+-+
      |                         ****  #  *  *   #           *   *  #                                        ****####     |
      |                         *  *  #  *  *   #           *   *  #  ****###   +++####            ****###  *  *   #     |
   1x +-++-++++++-++++****###++-*++*++#++*++*+-+#++****+++++*+++*++#++*++*-+#++*****++#++****###-++*++*-+#++*+-*+++#+-++-+
      |     *****###  *  *  #   *  *  #  *  *   #  *++*###  *   *  #  *  *  #  *   *  #  *  *++#   *  *  #  *  *   #     |
      |     *   *++#  *  *  #   *  *  #  *  *   #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #   *  *  #  *  *   #     |
 0.9x +-+---*****###--****###---****###--****####--****###--*****###--****###--*****###--****###---****###--****####---+-+
      ASSIGNMENT BITFIELD   FOURFP EMULATION   HUFFMAN   LU DECOMPOSITIONNEURAL NUMERIC SORSTRING SORT    hmean
  png: http://imgur.com/qO9ubtk
NB. cross here represents the previous commit.

-                            SPECint06 (test set), aarch64-linux-user. Host: Intel i7-4790K @ 4.00GHz

 1.5x +-+--------------------------------------------------------------------------------------------------------------+-+
      |                                                                       *****                                      |
      |                                                                       *+++*                           jr         |
      |                                                                       *   *                                      |
 1.4x +-+.....................................................................*...*.....................+++............+-+
      |                                                                       *   *                      |               |
      |                                      *****                            *   *                      |               |
      |                                      *   *                            *   *                    *****             |
 1.3x +-+....................................*...*............................*...*....................*.|.*...........+-+
      |                       +++            *   *                            *   *                    * | *             |
      |                      *****           *   *                            *   *                    *+++*             |
      |                      *   *           *   *                            *   *                    *   *             |
 1.2x +-+....................*...*...........*...*............................*...*...........*****....*...*...........+-+
      |     *****            *   *           *   *                            *   *           *   *    *   *    +++      |
      |     *   *            *   *           *   *                            *   *           *   *    *   *   *****     |
      |     *   *            *   *   *****   *   *                            *   *           *   *    *   *   *   *     |
 1.1x +-+...*...*............*...*...*...*...*...*............................*...*....+++....*...*....*...*...*...*...+-+
      |     *   *            *   *   *   *   *   *                            *   *   *****   *   *    *   *   *   *     |
      |     *   *            *   *   *   *   *   *   *****                    *   *   *   *   *   *    *   *   *   *     |
      |     *   *   *****    *   *   *   *   *   *   *   *   ******           *   *   *   *   *   *    *   *   *   *     |
   1x +-++-+*+++*-++*+++*++++*+-+*+++*-++*+++*-++*+++*+++*++-*++++*-++*****+++*++-*+++*++-*+++*+-+*++++*+++*++-*+++*+-++-+
      |     *   *   *   *    *   *   *   *   *   *   *   *   *    *   *+++*   *   *   *   *   *   *    *   *   *   *     |
      |     *   *   *   *    *   *   *   *   *   *   *   *   *    *   *   *   *   *   *   *   *   *    *   *   *   *     |
      |     *   *   *   *    *   *   *   *   *   *   *   *   *    *   *   *   *   *   *   *   *   *    *   *   *   *     |
 0.9x +-+---*****---*****----*****---*****---*****---*****---******---*****---*****---*****---*****----*****---*****---+-+
         astar   bzip2      gcc   gobmk h264ref   hmmlibquantum      mcf omnetpperlbench   sjengxalancbmk   hmean
  png: http://imgur.com/3Dp4vvq

-                           SPECint06 (train set), aarch64-linux-user. Host: Intel i7-4790K @ 4.00GHz

 1.7x +-+--------------------------------------------------------------------------------------------------------------+-+
      |                                                                                                                  |
      |                                                                                                       jr         |
 1.6x +-+...............................................................................................+++............+-+
      |                                                                                                *****             |
      |                                                                                                *+++*             |
      |                                                                                                *   *             |
 1.5x +-+..............................................................................................*...*...........+-+
      |                                                                        +++                     *   *             |
      |                                                                       *****                    *   *             |
 1.4x +-+.....................................................................*+++*....................*...*...........+-+
      |                                                                       *   *                    *   *             |
      |                                      *****                            *   *                    *   *             |
      |                                      *   *                            *   *   *****            *   *             |
 1.3x +-+....................................*...*............................*...*...*...*............*...*...........+-+
      |                       +++            *   *                            *   *   *   *            *   *             |
      |                      *****           *   *                            *   *   *   *   *****    *   *             |
 1.2x +-+....................*...*...........*...*............................*...*...*...*...*+++*....*...*...*****...+-+
      |                      *   *           *   *                            *   *   *   *   *   *    *   *   *+++*     |
      |     *****            *   *   *****   *   *                            *   *   *   *   *   *    *   *   *   *     |
      |     *   *            *   *   *+++*   *   *                            *   *   *   *   *   *    *   *   *   *     |
 1.1x +-+...*...*............*...*...*...*...*...*............................*...*...*...*...*...*....*...*...*...*...+-+
      |     *   *   *****    *   *   *   *   *   *                    *****   *   *   *   *   *   *    *   *   *   *     |
      |     *   *   *   *    *   *   *   *   *   *    +++    ******   *+++*   *   *   *   *   *   *    *   *   *   *     |
   1x +-+---*****---*****----*****---*****---*****---*****---******---*****---*****---*****---*****----*****---*****---+-+
         astar   bzip2      gcc   gobmk h264ref   hmmlibquantum      mcf omnetpperlbench   sjengxalancbmk   hmean
  png: http://imgur.com/vRrdc9j

Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-06-05 09:25:42 -07:00
Emilio G. Cota
e78722368c target/aarch64: optimize cross-page direct jumps in softmmu
Perf numbers in next commit's log.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-06-05 09:25:42 -07:00
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
Luc MICHEL
95e9a242e2 target/arm: add data cache invalidation cp15 instruction to cortex-r5
The cp15, CRn=15, opc1=0, CRm=5, opc2=0 instruction invalidates all the
data cache on the cortex-r5. Implementing it as a NOP.

Signed-off-by: Luc MICHEL <luc.michel@git.antfield.fr>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-06-04 18:42:55 +03:00
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
Michael Davidsaver
29c483a506 arm: add MPU support to M profile CPUs
The M series MPU is almost the same as the already implemented R
profile MPU (v7 PMSA).  So all we need to implement here is the MPU
register interface in the system register space.

This implementation has the same restriction as the R profile MPU
that it doesn't permit regions to be sized down smaller than 1K.

We also do not yet implement support for MPU_CTRL.HFNMIENA; this
bit should if zero disable use of the MPU when running HardFault,
NMI or with FAULTMASK set to 1 (ie at an execution priority of
less than zero) -- if the MPU is enabled we don't treat these
cases any differently.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Message-id: 1493122030-32191-13-git-send-email-peter.maydell@linaro.org
[PMM: Keep all the bits in mpu_ctrl field, rather than
 using SCTLR bits for them; drop broken HFNMIENA support;
 various cleanup]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-06-02 11:51:48 +01:00
Michael Davidsaver
5dd0641d23 armv7m: Classify faults as MemManage or BusFault
General logic is that operations stopped by the MPU are MemManage,
and those which go through the MPU and are caught by the unassigned
handle are BusFault. Distinguish these by looking at the
exception.fsr values, and set the CFSR bits and (if appropriate)
fill in the BFAR or MMFAR with the exception address.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Message-id: 1493122030-32191-12-git-send-email-peter.maydell@linaro.org
[PMM: i-side faults do not set BFAR/MMFAR, only d-side;
 added some CPU_LOG_INT logging]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-06-02 11:51:48 +01:00
Peter Maydell
790a11503c arm: All M profile cores are PMSA
All M profile CPUs are PMSA, so set the feature bit.
(We haven't actually implemented the M profile MPU register
interface yet, but setting this feature bit gives us closer
to correct behaviour for the MPU-disabled case.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1493122030-32191-11-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:48 +01:00
Michael Davidsaver
3a00d560bc armv7m: Implement M profile default memory map
Add support for the M profile default memory map which is used
if the MPU is not present or disabled.

The main differences in behaviour from implementing this
correctly are that we set the PAGE_EXEC attribute on
the right regions of memory, such that device regions
are not executable.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Message-id: 1493122030-32191-10-git-send-email-peter.maydell@linaro.org
[PMM: rephrased comment and commit message; don't mark
 the flash memory region as not-writable; list all
 the cases in the default map explicitly rather than
 using a 'default' case for the non-executable regions]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-06-02 11:51:48 +01:00
Michael Davidsaver
c9f9f1246d armv7m: Improve "-d mmu" tracing for PMSAv7 MPU
Improve the "-d mmu" tracing for the PMSAv7 MPU translation
process as an aid in debugging guest MPU configurations:
 * fix a missing newline for a guest-error log
 * report the region number with guest-error or unimp
   logs of bad region register values
 * add a log message for the overall result of the lookup
 * print "0x" prefix for hex values

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1493122030-32191-9-git-send-email-peter.maydell@linaro.org
[PMM: a little tidyup, report region number in all messages
 rather than just one]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-06-02 11:51:48 +01:00
Peter Maydell
e9235c6983 arm: Remove unnecessary check on cpu->pmsav7_dregion
Now that we enforce both:
 * pmsav7_dregion == 0 implies has_mpu == false
 * PMSA with has_mpu == false means SCTLR.M cannot be set
we can remove a check on pmsav7_dregion from get_phys_addr_pmsav7(),
because we can only reach this code path if the MPU is enabled
(and so region_translation_disabled() returned false).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1493122030-32191-8-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:48 +01:00
Peter Maydell
06312febfb arm: Don't let no-MPU PMSA cores write to SCTLR.M
If the CPU is a PMSA config with no MPU implemented, then the
SCTLR.M bit should be RAZ/WI, so that the guest can never
turn on the non-existent MPU.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1493122030-32191-7-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:48 +01:00
Peter Maydell
f50cd31413 arm: Don't clear ARM_FEATURE_PMSA for no-mpu configs
Fix the handling of QOM properties for PMSA CPUs with no MPU:

Allow no-MPU to be specified by either:
 * has-mpu = false
 * pmsav7_dregion = 0
and make setting one imply the other. Don't clear the PMSA
feature bit in this situation.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1493122030-32191-6-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:47 +01:00
Peter Maydell
452a095526 arm: Clean up handling of no-MPU PMSA CPUs
ARM CPUs come in two flavours:
 * proper MMU ("VMSA")
 * only an MPU ("PMSA")
For PMSA, the MPU may be implemented, or not (in which case there
is default "always acts the same" behaviour, but it isn't guest
programmable).

QEMU is a bit confused about how we indicate this: we have an
ARM_FEATURE_MPU, but it's not clear whether this indicates
"PMSA, not VMSA" or "PMSA and MPU present" , and sometimes we
use it for one purpose and sometimes the other.

Currently trying to implement a PMSA-without-MPU core won't
work correctly because we turn off the ARM_FEATURE_MPU bit
and then a lot of things which should still exist get
turned off too.

As the first step in cleaning this up, rename the feature
bit to ARM_FEATURE_PMSA, which indicates a PMSA CPU (with
or without MPU).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1493122030-32191-5-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:47 +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
e517d95b63 arm: Use the mmu_idx we're passed in arm_cpu_do_unaligned_access()
When identifying the DFSR format for an alignment fault, use
the mmu index that we are passed, rather than calling cpu_mmu_index()
to get the mmu index for the current CPU state. This doesn't actually
make any difference since the only cases where the current MMU index
differs from the index used for the load are the "unprivileged
load/store" instructions, and in that case the mmu index may
differ but the translation regime is the same (apart from the
"use from Hyp mode" case which is UNPREDICTABLE).
However it's the more logical thing to do.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1493122030-32191-2-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:47 +01:00
Wei Huang
2b3ffa9292 target/arm: clear PMUVER field of AA64DFR0 when vPMU=off
The PMUv3 driver of linux kernel (in arch/arm64/kernel/perf_event.c)
relies on the PMUVER field of id_aa64dfr0_el1 to decide if PMU support
is present or not. This patch clears the PMUVER field under TCG mode
when vPMU=off. Without it, PMUv3 will init insider guest VMs even
with vPMU=off. This patch also removes a redundant line inside the
if-statement.

Signed-off-by: Wei Huang <wei@redhat.com>
Message-id: 1495123889-32301-1-git-send-email-wei@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-06-02 11:51:47 +01:00
Eric Blake
cf83f14005 shutdown: Add source information to SHUTDOWN and RESET
Time to wire up all the call sites that request a shutdown or
reset to use the enum added in the previous patch.

It would have been less churn to keep the common case with no
arguments as meaning guest-triggered, and only modified the
host-triggered code paths, via a wrapper function, but then we'd
still have to audit that I didn't miss any host-triggered spots;
changing the signature forces us to double-check that I correctly
categorized all callers.

Since command line options can change whether a guest reset request
causes an actual reset vs. a shutdown, it's easy to also add the
information to reset requests.

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au> [ppc parts]
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> [SPARC part]
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x parts]
Message-Id: <20170515214114.15442-5-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-05-23 13:28:17 +02:00
Igor Mammedov
bd4c1bfe3e virt-arm: add node-id property to CPU
it will allow switching from cpu_index to property based
numa mapping in follow up patches.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Message-Id: <1494415802-227633-5-git-send-email-imammedo@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2017-05-11 16:08:49 -03:00
Igor Mammedov
46de5913b6 hw/arm/virt: extract mp-affinity calculation in separate function
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <1493816238-33120-3-git-send-email-imammedo@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2017-05-11 16:08:48 -03:00
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
Ishani Chugh
dffc58519e arm/kvm: Remove trailing newlines from error_report()
Signed-off-by: Ishani Chugh <chugh.ishani@research.iiit.ac.in>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1491629987-6826-1-git-send-email-chugh.ishani@research.iiit.ac.in
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-04-20 17:39:17 +01:00
Peter Maydell
65ed2ed90d target/arm: Add assertion about FSC format for syndrome registers
In tlb_fill() we construct a syndrome register value from a
fault status register value which is filled in by arm_tlb_fill().
arm_tlb_fill() returns FSR values which might be in the format
used with short-format page descriptors, or the format used
with long-format (LPAE) descriptors. The syndrome register
always uses LPAE-format FSR status codes.

It isn't actually possible to end up delivering a syndrome
register value to the guest for a fault which is reported
with a short-format FSR (that kind of stage 1 fault will only
happen for an AArch32 translation regime which doesn't have
a syndrome register, and can never be redirected to an AArch64
or Hyp exception level). Add an assertion which checks this,
and adjust the code so that we construct a syndrome with
an invalid status code, rather than allowing set bits in
the FSR input to randomly corrupt other fields in the syndrome.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1491486152-24304-1-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
2c4a7cc5af arm: Move excnames[] array into arm_log_exceptions()
The excnames[] array is defined in internals.h because we used
to use it from two different source files for handling logging
of AArch32 and AArch64 exception entry. Refactoring means that
it's now used only in arm_log_exception() in helper.c, so move
the array into that function.

Suggested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1491821097-5647-1-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
32b81e620e target/arm: Add missing entries to excnames[] for log strings
Recent changes have added new EXCP_ values to ARM but forgot
to update the excnames[] array which is used to provide
human-readable strings when printing information about the
exception for debug logging. Add the missing entries, and
add a comment to the list of #defines to help avoid the mistake
being repeated in future.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1491486340-25988-1-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
Andrew Jones
d5affb0d86 target/arm/arm-powerctl: Fix psci info return values
The power state spec section 5.1.5 AFFINITY_INFO defines the
affinity info return values as

  0 ON
  1 OFF
  2 ON_PENDING

I grepped QEMU for power_state to ensure that no assumptions
of OFF=0 were being made.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Message-id: 20170303123232.4967-1-drjones@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-03-14 11:28:54 +00:00
Andrew Baumann
6ecd0b6ba0 target/arm: implement armv8 PMUSERENR (user-mode enable bits)
In armv8, this register implements more than a single bit, with
fine-grained enables for read access to event counters, cycles
counters, and write access to the software increment. This change
implements those checks using custom access functions for the relevant
registers.

Signed-off-by: Andrew Baumann <Andrew.Baumann@microsoft.com>
Message-id: 20170228215801.10472-2-Andrew.Baumann@microsoft.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: move a couple of access functions to be only compiled
 ifndef CONFIG_USER_ONLY to avoid compiler warnings]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-03-14 11:28:54 +00:00
Alex Bennée
6568da459b target/arm/helper: make it clear the EC field is also in hex
..just like the rest of the displayed ESR register. Otherwise people
might scratch their heads if a not obviously hex number is displayed
for the EC field.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: KONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-03-09 10:41:48 +00:00
Paolo Bonzini
2ae41db262 KVM: do not use sigtimedwait to catch SIGBUS
Call kvm_on_sigbus_vcpu asynchronously from the VCPU thread.
Information for the SIGBUS can be stored in thread-local variables
and processed later in kvm_cpu_exec.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-03 16:40:02 +01:00
Paolo Bonzini
4d39892cca KVM: remove kvm_arch_on_sigbus
Build it on kvm_arch_on_sigbus_vcpu instead.  They do the same
for "action optional" SIGBUSes, and the main thread should never get
"action required" SIGBUSes because it blocks the signal.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-03 16:40:02 +01:00
Vijaya Kumar K
d3a3e52962 target-arm: Add GICv3CPUState in CPUARMState struct
Add gicv3state void pointer to CPUARMState struct
to store GICv3CPUState.

In case of usecase like CPU reset, we need to reset
GICv3CPUState of the CPU. In such scenario, this pointer
becomes handy.

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 1487850673-26455-5-git-send-email-vijay.kilari@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 17:10:00 +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
Peter Maydell
aa488fe3bb armv7m: Check exception return consistency
Implement the exception return consistency checks
described in the v7M pseudocode ExceptionReturn().

Inspired by a patch from Michael Davidsaver's series, but
this is a reimplementation from scratch based on the
ARM ARM pseudocode.

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
Peter Maydell
39ae2474e3 armv7m: Extract "exception taken" code into functions
Extract the code from the tail end of arm_v7m_do_interrupt() which
enters the exception handler into a pair of utility functions
v7m_exception_taken() and v7m_push_stack(), which correspond roughly
to the pseudocode PushStack() and ExceptionTaken().

This also requires us to move the arm_v7m_load_vector() utility
routine up so we can call it.

Handling illegal exception returns has some cases where we want to
take a UsageFault either on an existing stack frame or with a new
stack frame but with a specific LR value, so we want to be able to
call these without having to go via arm_v7m_cpu_do_interrupt().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:18 +00:00