Commit Graph

1865 Commits

Author SHA1 Message Date
Rémi Denis-Courmont
6c85f90626 target/arm: add 64-bit S-EL2 to EL exception table
With the ARMv8.4-SEL2 extension, EL2 is a legal exception level in
secure mode, though it can only be AArch64.

This patch adds the target EL for exceptions from 64-bit S-EL2.

It also fixes the target EL to EL2 when HCR.{A,F,I}MO are set in secure
mode. Those values were never used in practice as the effective value of
HCR was always 0 in secure mode.

Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210112104511.36576-7-remi.denis.courmont@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Rémi Denis-Courmont
5ca192dfc5 target/arm: Define isar_feature function to test for presence of SEL2
Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210112104511.36576-6-remi.denis.courmont@huawei.com
[PMM: tweaked commit message to match reduced scope of patch
 following rebase]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Rémi Denis-Courmont
59dd089cf9 target/arm: factor MDCR_EL2 common handling
This adds a common helper to compute the effective value of MDCR_EL2.
That is the actual value if EL2 is enabled in the current security
context, or 0 elsewise.

Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210112104511.36576-5-remi.denis.courmont@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Rémi Denis-Courmont
e04a5752cb target/arm: use arm_hcr_el2_eff() where applicable
This will simplify accessing HCR conditionally in secure state.

Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210112104511.36576-4-remi.denis.courmont@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Rémi Denis-Courmont
e6ef016926 target/arm: use arm_is_el2_enabled() where applicable
Do not assume that EL2 is available in and only in non-secure context.
That equivalence is broken by ARMv8.4-SEL2.

Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210112104511.36576-3-remi.denis.courmont@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Rémi Denis-Courmont
f3ee5160ce target/arm: add arm_is_el2_enabled() helper
This checks if EL2 is enabled (meaning EL2 registers take effects) in
the current security context.

Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210112104511.36576-2-remi.denis.courmont@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Rémi Denis-Courmont
cc974d5cd8 target/arm: remove redundant tests
In this context, the HCR value is the effective value, and thus is
zero in secure mode. The tests for HCR.{F,I}MO are sufficient.

Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210112104511.36576-1-remi.denis.courmont@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Richard Henderson
8073b87187 target/arm: Use object_property_add_bool for "sve" property
The interface for object_property_add_bool is simpler,
making the code easier to understand.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210111235740.462469-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Richard Henderson
eb94284d08 target/arm: Add cpu properties to control pauth
The crypto overhead of emulating pauth can be significant for
some workloads.  Add two boolean properties that allows the
feature to be turned off, on with the architected algorithm,
or on with an implementation defined algorithm.

We need two intermediate booleans to control the state while
parsing properties lest we clobber ID_AA64ISAR1 into an invalid
intermediate state.

Tested-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210111235740.462469-3-richard.henderson@linaro.org
[PMM: fixed docs typo, tweaked text to clarify that the impdef
algorithm is specific to QEMU]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Richard Henderson
283fc52ade target/arm: Implement an IMPDEF pauth algorithm
Without hardware acceleration, a cryptographically strong
algorithm is too expensive for pauth_computepac.

Even with hardware accel, we are not currently expecting
to link the linux-user binaries to any crypto libraries,
and doing so would generally make the --static build fail.

So choose XXH64 as a reasonably quick and decent hash.

Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210111235740.462469-2-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:51 +00:00
Keith Packard
0bb446d8b0 semihosting: Change common-semi API to be architecture-independent
The public API is now defined in
hw/semihosting/common-semi.h. do_common_semihosting takes CPUState *
instead of CPUARMState *. All internal functions have been renamed
common_semi_ instead of arm_semi_ or arm_. Aside from the API change,
there are no functional changes in this patch.

Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20210107170717.2098982-3-keithp@keithp.com>
Message-Id: <20210108224256.2321-14-alex.bennee@linaro.org>
2021-01-18 10:05:06 +00:00
Keith Packard
56b5170c87 semihosting: Move ARM semihosting code to shared directories
This commit renames two files which provide ARM semihosting support so
that they can be shared by other architectures:

 1. target/arm/arm-semi.c     -> hw/semihosting/common-semi.c
 2. linux-user/arm/semihost.c -> linux-user/semihost.c

The build system was modified use a new config variable,
CONFIG_ARM_COMPATIBLE_SEMIHOSTING, which has been added to the ARM
softmmu and linux-user default configs. The contents of the source
files has not been changed in this patch.

Signed-off-by: Keith Packard <keithp@keithp.com>
[AJB: rename arm-compat-semi, select SEMIHOSTING]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210107170717.2098982-2-keithp@keithp.com>
Message-Id: <20210108224256.2321-13-alex.bennee@linaro.org>
2021-01-18 10:05:06 +00:00
Alex Bennée
797920b952 target/arm: use official org.gnu.gdb.aarch64.sve layout for registers
While GDB can work with any XML description given to it there is
special handling for SVE registers on the GDB side which makes the
users life a little better. The changes aren't that major and all the
registers save the $vg reported the same. All that changes is:

  - report org.gnu.gdb.aarch64.sve
  - use gdb nomenclature for names and types
  - minor re-ordering of the types to match reference
  - re-enable ieee_half (as we know gdb supports it now)
  - $vg is now a 64 bit int
  - check $vN and $zN aliasing in test

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Machado <luis.machado@linaro.org>
Message-Id: <20210108224256.2321-11-alex.bennee@linaro.org>
2021-01-18 10:05:06 +00:00
Alex Bennée
ad9dcb207b gdbstub: drop CPUEnv from gdb_exit()
gdb_exit() has never needed anything from env and I doubt we are going
to start now.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210108224256.2321-8-alex.bennee@linaro.org>
2021-01-18 10:05:06 +00:00
Peter Maydell
e4d51ac692 target/arm: Don't decode insns in the XScale/iWMMXt space as cp insns
In commit cd8be50e58 we converted the A32 coprocessor
insns to decodetree. This accidentally broke XScale/iWMMXt insns,
because it moved the handling of "cp insns which are handled
by looking up the cp register in the hashtable" from after the
call to the legacy disas_xscale_insn() decode to before it,
with the result that all XScale/iWMMXt insns now UNDEF.

Update valid_cp() so that it knows that on XScale cp 0 and 1
are not standard coprocessor instructions; this will cause
the decodetree trans_ functions to ignore them, so that
execution will correctly get through to the legacy decode again.

Cc: qemu-stable@nongnu.org
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Message-id: 20210108195157.32067-1-peter.maydell@linaro.org
2021-01-12 21:19:02 +00:00
Leif Lindholm
bd78b6be24 target/arm: add aarch32 ID register fields to cpu.h
Add entries present in ARM DDI 0487F.c (August 2020).

Signed-off-by: Leif Lindholm <leif@nuviainc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20210108185154.8108-7-leif@nuviainc.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-12 10:09:14 +00:00
Leif Lindholm
00a92832f4 target/arm: add aarch64 ID register fields to cpu.h
Add entries present in ARM DDI 0487F.c (August 2020).

Signed-off-by: Leif Lindholm <leif@nuviainc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20210108185154.8108-6-leif@nuviainc.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-12 10:09:14 +00:00
Leif Lindholm
2a14526a6f target/arm: add descriptions of CLIDR_EL1, CCSIDR_EL1, CTR_EL0 to cpu.h
Signed-off-by: Leif Lindholm <leif@nuviainc.com>
Reviewed-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20210108185154.8108-5-leif@nuviainc.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-12 10:09:14 +00:00
Leif Lindholm
a5fd319ae7 target/arm: make ARMCPU.ctr 64-bit
When FEAT_MTE is implemented, the AArch64 view of CTR_EL0 adds the
TminLine field in bits [37:32].
Extend the ctr field to be able to hold this context.

Signed-off-by: Leif Lindholm <leif@nuviainc.com>
Reviewed-by: Hao Wu <wuhaotsh@google.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20210108185154.8108-4-leif@nuviainc.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-12 10:09:14 +00:00
Leif Lindholm
f6450bcb6b target/arm: make ARMCPU.clidr 64-bit
The AArch64 view of CLIDR_EL1 extends the ICB field to include also bit
32, as well as adding a Ttype<n> field when FEAT_MTE is implemented.
Extend the clidr field to be able to hold this context.

Signed-off-by: Leif Lindholm <leif@nuviainc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20210108185154.8108-3-leif@nuviainc.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-12 10:09:13 +00:00
Leif Lindholm
9a286bcdfd target/arm: fix typo in cpu.h ID_AA64PFR1 field name
SBSS -> SSBS

Signed-off-by: Leif Lindholm <leif@nuviainc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20210108185154.8108-2-leif@nuviainc.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-12 10:09:13 +00:00
Rémi Denis-Courmont
078e9fe3cb target/arm: enable Small Translation tables in max CPU
Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-12 10:04:10 +00:00
Rémi Denis-Courmont
c36c65ea3c target/arm: ARMv8.4-TTST extension
This adds for the Small Translation tables extension in AArch64 state.

Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-12 10:03:04 +00:00
Peter Maydell
2d3bf65327 target/arm: Remove timer_del()/timer_deinit() before timer_free()
The Arm CPU finalize function uses a sequence of timer_del(), timer_deinit(),
timer_free() to free the timer. The timer_deinit() step in this was always
unnecessary, and now the timer_del() is implied by timer_free(), so we can
collapse this down to simply calling timer_free().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201215154107.3255-5-peter.maydell@linaro.org
2021-01-08 15:13:38 +00:00
Peter Maydell
590e05d6b4 target/arm: Implement Cortex-M55 model
Now that we have implemented all the features needed by the v8.1M
architecture, we can add the model of the Cortex-M55.  This is the
configuration without MVE support; we'll add MVE later.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201210201433.26262-5-peter.maydell@linaro.org
2021-01-08 15:13:38 +00:00
Peter Maydell
eb20dafdbf target/arm: Implement FPCXT_NS fp system register
Implement the v8.1M FPCXT_NS floating-point system register.  This is
a little more complicated than FPCXT_S, because it has specific
handling for "current FP state is inactive", and it only wants to do
PreserveFPState(), not the full set of actions done by
ExecuteFPCheck() which vfp_access_check() implements.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201210201433.26262-4-peter.maydell@linaro.org
2021-01-08 15:13:38 +00:00
Peter Maydell
7fbf95a037 target/arm: Correct store of FPSCR value via FPCXT_S
In commit 64f863baee we implemented the v8.1M FPCXT_S register,
but we got the write behaviour wrong. On read, this register reads
bits [27:0] of FPSCR plus the CONTROL.SFPA bit. On write, it doesn't
just write back those bits -- it writes a value to the whole FPSCR,
whose upper 4 bits are zeroes.

We also incorrectly implemented the write-to-FPSCR as a simple store
to vfp.xregs; this skips the "update the softfloat flags" part of
the vfp_set_fpscr helper so the value would read back correctly but
not actually take effect.

Fix both of these things by doing a complete write to the FPSCR
using the helper function.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201210201433.26262-3-peter.maydell@linaro.org
2021-01-08 15:13:38 +00:00
Richard Henderson
cc97b0019b target/arm: Fix MTE0_ACTIVE
In 50244cc76a we updated mte_check_fail to match the ARM
pseudocode, using the correct EL to select the TCF field.
But we failed to update MTE0_ACTIVE the same way, which led
to g_assert_not_reached().

Cc: qemu-stable@nongnu.org
Buglink: https://bugs.launchpad.net/bugs/1907137
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201221204426.88514-1-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-08 15:13:38 +00:00
Richard Henderson
04a37d4ca4 tcg: Make tb arg to synchronize_from_tb const
There is nothing within the translators that ought to be
changing the TranslationBlock data, so make it const.

This does not actually use the read-only copy of the
data structure that exists within the rx region.

Reviewed-by: Joelle van Dyne <j@getutm.app>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-01-07 05:09:41 -10:00
Richard Henderson
d997143533 tcg: Make DisasContextBase.tb const
There is nothing within the translators that ought to be
changing the TranslationBlock data, so make it const.

This does not actually use the read-only copy of the
data structure that exists within the rx region.

Reviewed-by: Joelle van Dyne <j@getutm.app>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-01-07 05:09:41 -10:00
Markus Armbruster
3ddba9a9e9 migration: Replace migration's JSON writer by the general one
Commit 8118f0950f "migration: Append JSON description of migration
stream" needs a JSON writer.  The existing qobject_to_json() wasn't a
good fit, because it requires building a QObject to convert.  Instead,
migration got its very own JSON writer, in commit 190c882ce2 "QJSON:
Add JSON writer".  It tacitly limits numbers to int64_t, and strings
contents to characters that don't need escaping, unlike
qobject_to_json().

The previous commit factored the JSON writer out of qobject_to_json().
Replace migration's JSON writer by it.

Cc: Juan Quintela <quintela@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-17-armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-12-19 10:39:16 +01:00
Eric Blake
54aa3de72e qapi: Use QAPI_LIST_PREPEND() where possible
Anywhere we create a list of just one item or by prepending items
(typically because order doesn't matter), we can use
QAPI_LIST_PREPEND().  But places where we must keep the list in order
by appending remain open-coded until later patches.

Note that as a side effect, this also performs a cleanup of two minor
issues in qga/commands-posix.c: the old code was performing
 new = g_malloc0(sizeof(*ret));
which 1) is confusing because you have to verify whether 'new' and
'ret' are variables with the same type, and 2) would conflict with C++
compilation (not an actual problem for this file, but makes
copy-and-paste harder).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201113011340.463563-5-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
[Straightforward conflicts due to commit a8aa94b5f8 "qga: update
schema for guest-get-disks 'dependents' field" and commit a10b453a52
"target/mips: Move mips_cpu_add_definition() from helper.c to cpu.c"
resolved.  Commit message tweaked.]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-12-19 10:20:14 +01:00
Eduardo Habkost
85cc807cbc arm/cpu64: Register "aarch64" as class property
Class properties make QOM introspection simpler and easier, as
they don't require an object to be instantiated.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20201111183823.283752-8-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-12-15 10:02:07 -05:00
Paolo Bonzini
6e504a989d arm: do not use ram_size global
Use the machine properties instead.

Cc: qemu-ppc@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:07 -05:00
Peter Maydell
46f4976f22 target/arm: Implement M-profile "minimal RAS implementation"
For v8.1M the architecture mandates that CPUs must provide at
least the "minimal RAS implementation" from the Reliability,
Availability and Serviceability extension. This consists of:
 * an ESB instruction which is a NOP
   -- since it is in the HINT space we need only add a comment
 * an RFSR register which will RAZ/WI
 * a RAZ/WI AIRCR.IESB bit
   -- the code which handles writes to AIRCR does not allow setting
      of RES0 bits, so we already treat this as RAZ/WI; add a comment
      noting that this is deliberate
 * minimal implementation of the RAS register block at 0xe0005000
   -- this will be in a subsequent commit
 * setting the ID_PFR0.RAS field to 0b0010
   -- we will do this when we add the Cortex-M55 CPU model

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-26-peter.maydell@linaro.org
2020-12-10 11:44:56 +00:00
Peter Maydell
7f48414736 target/arm: Implement CCR_S.TRD behaviour for SG insns
v8.1M introduces a new TRD flag in the CCR register, which enables
checking for stack frame integrity signatures on SG instructions.
Add the code in the SG insn implementation for the new behaviour.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-24-peter.maydell@linaro.org
2020-12-10 11:44:56 +00:00
Peter Maydell
0e83f905fb hw/intc/armv7m_nvic: Support v8.1M CCR.TRD bit
v8.1M introduces a new TRD flag in the CCR register, which enables
checking for stack frame integrity signatures on SG instructions.
This bit is not banked, and is always RAZ/WI to Non-secure code.
Adjust the code for handling CCR reads and writes to handle this.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-23-peter.maydell@linaro.org
2020-12-10 11:44:56 +00:00
Peter Maydell
fe6fa228a7 target/arm: Implement new v8.1M VLLDM and VLSTM encodings
v8.1M adds new encodings of VLLDM and VLSTM (where bit 7 is set).
The only difference is that:
 * the old T1 encodings UNDEF if the implementation implements 32
   Dregs (this is currently architecturally impossible for M-profile)
 * the new T2 encodings have the implementation-defined option to
   read from memory (discarding the data) or write UNKNOWN values to
   memory for the stack slots that would be D16-D31

We choose not to make those accesses, so for us the two
instructions behave identically assuming they don't UNDEF.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-21-peter.maydell@linaro.org
2020-12-10 11:44:56 +00:00
Peter Maydell
3423fbf104 target/arm: Implement new v8.1M NOCP check for exception return
In v8.1M a new exception return check is added which may cause a NOCP
UsageFault (see rule R_XLTP): before we clear s0..s15 and the FPSCR
we must check whether access to CP10 from the Security state of the
returning exception is disabled; if it is then we must take a fault.

(Note that for our implementation CPPWR is always RAZ/WI and so can
never cause CP10 accesses to fail.)

The other v8.1M change to this register-clearing code is that if MVE
is implemented VPR must also be cleared, so add a TODO comment to
that effect.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-20-peter.maydell@linaro.org
2020-12-10 11:44:56 +00:00
Peter Maydell
be9500bb17 target/arm: In v8.1M, don't set HFSR.FORCED on vector table fetch failures
In v8.1M, vector table fetch failures don't set HFSR.FORCED (see rule
R_LLRP).  (In previous versions of the architecture this was either
required or IMPDEF.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-18-peter.maydell@linaro.org
2020-12-10 11:44:56 +00:00
Peter Maydell
a59b1ed618 target/arm: For v8.1M, always clear R0-R3, R12, APSR, EPSR on exception entry
In v8.0M, on exception entry the registers R0-R3, R12, APSR and EPSR
are zeroed for an exception taken to Non-secure state; for an
exception taken to Secure state they become UNKNOWN, and we chose to
leave them at their previous values.

In v8.1M the behaviour is specified more tightly and these registers
are always zeroed regardless of the security state that the exception
targets (see rule R_KPZV).  Implement this.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-17-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell
99c7834fba hw/intc/armv7m_nvic: Update FPDSCR masking for v8.1M
The FPDSCR register has a similar layout to the FPSCR.  In v8.1M it
gains new fields FZ16 (if half-precision floating point is supported)
and LTPSIZE (always reads as 4).  Update the reset value and the code
that handles writes to this register accordingly.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-16-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell
64f863baee target/arm: Implement FPCXT_S fp system register
Implement the new-in-v8.1M FPCXT_S floating point system register.
This is for saving and restoring the secure floating point context,
and it reads and writes bits [27:0] from the FPSCR and the
CONTROL.SFPA bit in bit [31].

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-14-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell
96dfae6866 target/arm: Factor out preserve-fp-state from full_vfp_access_check()
Factor out the code which handles M-profile lazy FP state preservation
from full_vfp_access_check(); accesses to the FPCXT_NS register are
a special case which need to do just this part (corresponding in the
pseudocode to the PreserveFPState() function), and not the full
set of actions matching the pseudocode ExecuteFPCheck() which
normal FP instructions need to do.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20201119215617.29887-13-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell
6a017acdf8 target/arm: Use new FPCR_NZCV_MASK constant
We defined a constant name for the mask of NZCV bits in the FPCR/FPSCR
in the previous commit; use it in a couple of places in existing code,
where we're masking out everything except NZCV for the "load to Rt=15
sets CPSR.NZCV" special case.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-12-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell
9542c30bcf target/arm: Implement M-profile FPSCR_nzcvqc
v8.1M defines a new FP system register FPSCR_nzcvqc; this behaves
like the existing FPSCR, except that it reads and writes only bits
[31:27] of the FPSCR (the N, Z, C, V and QC flag bits).  (Unlike the
FPSCR, the special case for Rt=15 of writing the CPSR.NZCV is not
permitted.)

Implement the register.  Since we don't yet implement MVE, we handle
the QC bit as RES0, with todo comments for where we will need to add
support later.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-11-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell
0bf0dd4dcb target/arm: Implement VLDR/VSTR system register
Implement the new-in-v8.1M VLDR/VSTR variants which directly
read or write FP system registers to memory.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-10-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell
f7ed0c9433 target/arm: Move general-use constant expanders up in translate.c
The constant-expander functions like negate, plus_2, etc, are
generally useful; move them up in translate.c so we can use them in
the VFP/Neon decoders as well as in the A32/T32/T16 decoders.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-9-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell
32a290b8c3 target/arm: Refactor M-profile VMSR/VMRS handling
Currently M-profile borrows the A-profile code for VMSR and VMRS
(access to the FP system registers), because all it needs to support
is the FPSCR.  In v8.1M things become significantly more complicated
in two ways:

 * there are several new FP system registers; some have side effects
   on read, and one (FPCXT_NS) needs to avoid the usual
   vfp_access_check() and the "only if FPU implemented" check

 * all sysregs are now accessible both by VMRS/VMSR (which
   reads/writes a general purpose register) and also by VLDR/VSTR
   (which reads/writes them directly to memory)

Refactor the structure of how we handle VMSR/VMRS to cope with this:

 * keep the M-profile code entirely separate from the A-profile code

 * abstract out the "read or write the general purpose register" part
   of the code into a loadfn or storefn function pointer, so we can
   reuse it for VLDR/VSTR.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-8-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell
ede97c9d71 target/arm: Enforce M-profile VMRS/VMSR register restrictions
For M-profile before v8.1M, the only valid register for VMSR/VMRS is
the FPSCR.  We have a comment that states this, but the actual logic
to forbid accesses for any other register value is missing, so we
would end up with A-profile style behaviour.  Add the missing check.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-7-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00