Commit Graph

32 Commits

Author SHA1 Message Date
Alex Bennée
f654387b81 target/arm: hide all versions of DBGD[RS]AR from gdbstub
This avoids two duplicates being presented to gdbstub. As the
registers are RAZ anyway it is unlikely their value would be of use to
someone using gdbstub anyway.

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231106185112.2755262-5-alex.bennee@linaro.org>
2023-11-08 15:15:23 +00:00
Peter Maydell
5a534314a8 target/arm: Move feature test functions to their own header
The feature test functions isar_feature_*() now take up nearly
a thousand lines in target/arm/cpu.h. This header file is included
by a lot of source files, most of which don't need these functions.
Move the feature test functions to their own header file.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20231024163510.2972081-2-peter.maydell@linaro.org
2023-10-27 11:44:32 +01:00
Peter Maydell
5d78893f39 target/arm: Special case M-profile in debug_helper.c code
A lot of the code called from helper_exception_bkpt_insn() is written
assuming A-profile, but we will also call this helper on M-profile
CPUs when they execute a BKPT insn.  This used to work by accident,
but recent changes mean that we will hit an assert when some of this
code calls down into lower level functions that end up calling
arm_security_space_below_el3(), arm_el_is_aa64(), and other functions
that now explicitly assert that the guest CPU is not M-profile.

Handle M-profile directly to avoid the assertions:
 * in arm_debug_target_el(), M-profile debug exceptions always
   go to EL1
 * in arm_debug_exception_fsr(), M-profile always uses the short
   format FSR (compare commit d7fe699be5, though in this case
   the code in arm_v7m_cpu_do_interrupt() does not need to
   look at the FSR value at all)

Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1775
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230721143239.1753066-1-peter.maydell@linaro.org
2023-07-25 10:56:51 +01:00
Zhuojia Shen
f9ac778898 target/arm: trap DCC access in user mode emulation
Accessing EL0-accessible Debug Communication Channel (DCC) registers in
user mode emulation is currently enabled.  However, it does not match
Linux behavior as Linux sets MDSCR_EL1.TDCC on startup to disable EL0
access to DCC (see __cpu_setup() in arch/arm64/mm/proc.S).

This patch fixes access_tdcc() to check MDSCR_EL1.TDCC for EL0 and sets
MDSCR_EL1.TDCC for user mode emulation to match Linux.

Signed-off-by: Zhuojia Shen <chaosdefinition@hotmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: DS7PR12MB630905198DD8E69F6817544CAC4EA@DS7PR12MB6309.namprd12.prod.outlook.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-06-06 10:19:40 +01:00
Alex Bennée
70a670cadb target/arm: add RAZ/WI handling for DBGDTR[TX|RX]
The commit b3aa2f2128 (target/arm: provide stubs for more external
debug registers) was added to handle HyperV's unconditional usage of
Debug Communications Channel. It turns out that Linux will similarly
break if you enable CONFIG_HVC_DCC "ARM JTAG DCC console".

Extend the registers we RAZ/WI set to avoid this.

Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Evgeny Iakovlev <eiakovlev@linux.microsoft.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230516104420.407912-1-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-05-18 11:09:36 +01:00
Fabiano Rosas
2059ec754f target/arm: Wrap TCG-only code in debug_helper.c
The next few patches will move helpers under CONFIG_TCG. We'd prefer
to keep the debug helpers and debug registers close together, so
rearrange the file a bit to be able to wrap the helpers with a TCG
ifdef.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-02-27 13:27:04 +00:00
Fabiano Rosas
fa05d1abb9 target/arm: Wrap breakpoint/watchpoint updates with tcg_enabled
This is in preparation for restricting compilation of some parts of
debug_helper.c to TCG only.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-02-27 13:27:04 +00:00
Peter Maydell
1748ef03c5 target/arm: Implement MDCR_EL2.TDCC and MDCR_EL3.TDCC traps
FEAT_FGT also implements an extra trap bit in the MDCR_EL2 and
MDCR_EL3 registers: bit TDCC enables trapping of use of the Debug
Comms Channel registers OSDTRRX_EL1, OSDTRTX_EL1, MDCCSR_EL0,
MDCCINT_EL0, DBGDTR_EL0, DBGDTRRX_EL0 and DBGDTRTX_EL0 (and their
AArch32 equivalents).  This trapping is independent of whether
fine-grained traps are enabled or not.

Implement these extra traps.  (We don't implement DBGDTR_EL0,
DBGDTRRX_EL0 and DBGDTRTX_EL0.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Fuad Tabba <tabba@google.com>
Message-id: 20230130182459.3309057-23-peter.maydell@linaro.org
Message-id: 20230127175507.2895013-23-peter.maydell@linaro.org
2023-02-03 12:59:24 +00:00
Peter Maydell
917b1405c1 target/arm: Mark up sysregs for HDFGRTR bits 0..11
Mark up the sysreg definitons for the registers trapped
by HDFGRTR/HDFGWTR bits 0..11. These cover various debug
related registers.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Fuad Tabba <tabba@google.com>
Message-id: 20230130182459.3309057-15-peter.maydell@linaro.org
Message-id: 20230127175507.2895013-15-peter.maydell@linaro.org
2023-02-03 12:59:23 +00:00
Evgeny Iakovlev
b3aa2f2128 target/arm: provide stubs for more external debug registers
Qemu doesn't implement Debug Communication Channel, as well as the rest
of external debug interface. However, Microsoft Hyper-V in tries to
access some of those registers during an EL2 context switch.

Since there is no architectural way to not advertise support for external
debug, provide RAZ/WI stubs for OSDTRRX_EL1, OSDTRTX_EL1 and OSECCR_EL1
registers in the same way the rest of DCM is currently done. Do account
for access traps though with access_tda.

Signed-off-by: Evgeny Iakovlev <eiakovlev@linux.microsoft.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230120155929.32384-3-eiakovlev@linux.microsoft.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-01-23 13:32:38 +00:00
Evgeny Iakovlev
5fc83f1128 target/arm: implement DBGCLAIM registers
The architecture does not define any functionality for the CLAIM tag bits.
So we will just keep the raw bits, as per spec.

Signed-off-by: Evgeny Iakovlev <eiakovlev@linux.microsoft.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230120155929.32384-2-eiakovlev@linux.microsoft.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-01-23 13:32:38 +00:00
Tobias Röhmel
452c67a427 target/arm: Enable TTBCR_EAE for ARMv8-R AArch32
ARMv8-R AArch32 CPUs behave as if TTBCR.EAE is always 1 even
tough they don't have the TTBCR register.
See ARM Architecture Reference Manual Supplement - ARMv8, for the ARMv8-R
AArch32 architecture profile Version:A.c section C1.2.

Signed-off-by: Tobias Röhmel <tobias.roehmel@rwth-aachen.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20221206102504.165775-5-tobias.roehmel@rwth-aachen.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-01-05 11:51:09 +00:00
Peter Maydell
cb4a0a3444 target/arm: Store TCR_EL* registers as uint64_t
Change the representation of the TCR_EL* registers in the CPU state
struct from struct TCR to uint64_t.  This allows us to drop the
custom vmsa_ttbcr_raw_write() function, moving the "enforce RES0"
checks to their more usual location in the writefn
vmsa_ttbcr_write().  We also don't need the resetfn any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220714132303.1287193-7-peter.maydell@linaro.org
2022-07-18 13:20:13 +01:00
Peter Maydell
f94a6df5dd target/arm: Correctly implement Feat_DoubleLock
The architecture defines the OS DoubleLock as a register which
(similarly to the OS Lock) suppresses debug events for use in CPU
powerdown sequences.  This functionality is required in Arm v7 and
v8.0; from v8.2 it becomes optional and in v9 it must not be
implemented.

Currently in QEMU we implement the OSDLR_EL1 register as a NOP.  This
is wrong both for the "feature implemented" and the "feature not
implemented" cases: if the feature is implemented then the DLK bit
should read as written and cause suppression of debug exceptions, and
if it is not implemented then the bit must be RAZ/WI.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-07-07 11:38:36 +01:00
Peter Maydell
09754ca867 target/arm: Implement AArch32 DBGDEVID, DBGDEVID1, DBGDEVID2
Starting with v7 of the debug architecture, there are three extra
ID registers that add information on top of that provided in
DBGDIDR. These are DBGDEVID, DBGDEVID1 and DBGDEVID2. In the
v7 debug architecture, DBGDEVID is optional, present only of
DBGDIDR.DEVID_imp is set. In v7.1 all three must be present.

Implement the missing registers.  Note that we only need to set the
values in the ARMISARegisters struct for the CPUs Cortex-A7, A15,
A53, A57 and A72 (plus the 32-bit 'max' which uses the Cortex-A53
values): earlier CPUs didn't implement v7 of the architecture, and
our other 64-bit CPUs (Cortex-A76, Neoverse-N1 and A64fx) don't have
AArch32 support at EL1.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220630194116.3438513-5-peter.maydell@linaro.org
2022-07-07 11:37:33 +01:00
Peter Maydell
40b200279c target/arm: Suppress debug exceptions when OS Lock set
The "OS Lock" in the Arm debug architecture is a way for software
to suppress debug exceptions while it is trying to power down
a CPU and save the state of the breakpoint and watchpoint
registers. In QEMU we implemented the support for writing
the OS Lock bit via OSLAR_EL1 and reading it via OSLSR_EL1,
but didn't implement the actual behaviour.

The required behaviour with the OS Lock set is:
 * debug exceptions (apart from BKPT insns) are suppressed
 * some MDSCR_EL1 bits allow write access to the corresponding
   EDSCR external debug status register that they shadow
   (we can ignore this because we don't implement external debug)
 * similarly with the OSECCR_EL1 which shadows the EDECCR
   (but we don't implement OSECCR_EL1 anyway)

Implement the missing behaviour of suppressing debug
exceptions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220630194116.3438513-4-peter.maydell@linaro.org
2022-07-07 11:37:33 +01:00
Peter Maydell
f43ee493c2 target/arm: Move define_debug_regs() to debug_helper.c
The target/arm/helper.c file is very long and is a grabbag of all
kinds of functionality.  We have already a debug_helper.c which has
code for implementing architectural debug.  Move the code which
defines the debug-related system registers out to this file also.
This affects the define_debug_regs() function and the various
functions and arrays which are used only by it.

The functions raw_write() and arm_mdcr_el2_eff() and
define_debug_regs() now need to be global rather than local to
helper.c; everything else is pure code movement.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220630194116.3438513-3-peter.maydell@linaro.org
2022-07-07 11:37:33 +01:00
Richard Henderson
38e8a13c11 target/arm: Move arm_debug_target_el to debug_helper.c
This function is no longer used outside debug_helper.c.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220609202901.1177572-23-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-06-10 14:32:35 +01:00
Richard Henderson
04eacf6e79 target/arm: Create raise_exception_debug
Handle the debug vs current el exception test in one place.
Leave EXCP_BKPT alone, since that treats debug < current differently.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220609202901.1177572-22-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-06-10 14:32:34 +01:00
Richard Henderson
f0d7c2054a target/arm: Create helper_exception_swstep
Move the computation from gen_swstep_exception into a helper.

This fixes a bug when:
  - MDSCR_EL1.KDE == 1 to enable debug exceptions within EL_D itself
  - we singlestep an ERET from EL_D to some lower EL

Previously we were computing 'same el' based on the EL which
executed the ERET instruction, whereas it ought to be computed
based on the EL to which ERET returned.  This happens naturally
with the new helper, which runs after EL has been changed.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220609202901.1177572-14-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-06-10 14:32:32 +01:00
Richard Henderson
a853e3ae55 target/arm: Move arm_debug_exception_fsr to debug_helper.c
This function now now only used in debug_helper.c, so there is
no reason to have a declaration in a header.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220609202901.1177572-9-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-06-10 14:32:31 +01:00
Richard Henderson
16f9d5f693 target/arm: Move exception_bkpt_insn to debug_helper.c
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220609202901.1177572-8-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-06-10 14:32:31 +01:00
Richard Henderson
831c1b1087 target/arm: Use is_a64 in arm_generate_debug_exceptions
Use the accessor rather than the raw structure member.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220609202901.1177572-7-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-06-10 14:32:31 +01:00
Richard Henderson
31c8df53ee target/arm: Move arm_generate_debug_exceptions out of line
Move arm_generate_debug_exceptions and its two subroutines,
{aa32,aa64}_generate_debug_exceptions into debug_helper.c,
and the one interface declaration to internals.h.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220609202901.1177572-6-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-06-10 14:32:31 +01:00
Richard Henderson
55ba15b737 target/arm: Move arm_singlestep_active out of line
Move the function to debug_helper.c, and the
declaration to internals.h.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220609202901.1177572-5-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-06-10 14:32:30 +01:00
Richard Henderson
8b7a5bbecf target/arm: Use field names for accessing DBGWCRn
While defining these names, use the correct field width of 5 not 4 for
DBGWCR.MASK.  This typo prevented setting a watchpoint larger than 32k.

Reported-by: Chris Howard <cvz185@web.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20220427051926.295223-1-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-04-28 13:40:16 +01:00
Richard Henderson
8dc89f1faa target/arm: Suppress bp for exceptions with more priority
Both single-step and pc alignment faults have priority over
breakpoint exceptions.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-12-15 10:35:26 +00:00
Richard Henderson
b5cf742841 accel/tcg: Remove TranslatorOps.breakpoint_check
The hook is now unused, with breakpoints checked outside translation.

Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-07-21 07:47:05 -10:00
Richard Henderson
b00d86bc8b target/arm: Implement debug_check_breakpoint
Reuse the code at the bottom of helper_check_breakpoints,
which is what we currently call from *_tr_breakpoint_check.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-07-21 07:47:04 -10:00
Peter Maydell
88ce6c6ee8 target/arm: Stop assuming DBGDIDR always exists
The AArch32 DBGDIDR defines properties like the number of
breakpoints, watchpoints and context-matching comparators.  On an
AArch64 CPU, the register may not even exist if AArch32 is not
supported at EL1.

Currently we hard-code use of DBGDIDR to identify the number of
breakpoints etc; this works for all our TCG CPUs, but will break if
we ever add an AArch64-only CPU.  We also have an assert() that the
AArch32 and AArch64 registers match, which currently works only by
luck for KVM because we don't populate either of these ID registers
from the KVM vCPU and so they are both zero.

Clean this up so we have functions for finding the number
of breakpoints, watchpoints and context comparators which look
in the appropriate ID register.

This allows us to drop the "check that AArch64 and AArch32 agree
on the number of breakpoints etc" asserts:
 * we no longer look at the AArch32 versions unless that's the
   right place to be looking
 * it's valid to have a CPU (eg AArch64-only) where they don't match
 * we shouldn't have been asserting the validity of ID registers
   in a codepath used with KVM anyway

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200214175116.9164-11-peter.maydell@linaro.org
2020-02-21 16:07:01 +00:00
Richard Henderson
e2a1a4616c target/arm: Add CONTEXTIDR_EL2
Not all of the breakpoint types are supported, but those that
only examine contextidr are extended to support the new register.

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200206105448.4726-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-02-07 14:04:21 +00:00
Philippe Mathieu-Daudé
9dd5cca424 target/arm: Move debug routines to debug_helper.c
These routines are TCG specific.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190701194942.10092-2-philmd@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-07-04 17:14:43 +01:00