Commit Graph

158 Commits

Author SHA1 Message Date
Peter Maydell
514b4f361b nvic: Expose NMI line
On real v7M hardware, the NMI line is an externally visible signal
that an SoC or board can toggle to assert an NMI. Expose it in
our QEMU NVIC and armv7m container objects so that a board model
can wire it up if it needs to.

In particular, the MPS2 watchdog is wired to NMI.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2018-08-20 11:24:33 +01:00
Julia Suvorova
c4379b4874 nvic: Change NVIC to support ARMv6-M
The differences from ARMv7-M NVIC are:
  * ARMv6-M only supports up to 32 external interrupts
   (configurable feature already). The ICTR is reserved.
  * Active Bit Register is reserved.
  * ARMv6-M supports 4 priority levels against 256 in ARMv7-M.

Signed-off-by: Julia Suvorova <jusual@mail.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-08-14 17:17:19 +01:00
Julia Suvorova
22ab346001 arm: Add ARMv6-M programmer's model support
Forbid stack alignment change. (CCR)
Reserve FAULTMASK, BASEPRI registers.
Report any fault as a HardFault. Disable MemManage, BusFault and
UsageFault, so they always escalated to HardFault. (SHCSR)

Signed-off-by: Julia Suvorova <jusual@mail.ru>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20180718095628.26442-1-jusual@mail.ru
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-08-14 17:17:19 +01:00
Julia Suvorova
7c9140afd5 nvic: Handle ARMv6-M SCS reserved registers
Handle SCS reserved registers listed in ARMv6-M ARM D3.6.1.
All reserved registers are RAZ/WI. ARM_FEATURE_M_MAIN is used for the
checks, because these registers are reserved in ARMv8-M Baseline too.

Signed-off-by: Julia Suvorova <jusual@mail.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-08-14 17:17:19 +01:00
Peter Maydell
942566ffc1 armv7m_nvic: Fix m-security subsection name
The vmstate save/load code insists that subsections of a VMState must
have names which include their parent VMState's name as a leading
substring.  Unfortunately it neither documents this nor checks it on
device init or state save, but instead fails state load with a
confusing error message ("Missing section footer for armv7m_nvic").

Fix the name of the m-security subsection of the NVIC, so that
state save/load works correctly for the security-enabled NVIC.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180727113854.20283-2-peter.maydell@linaro.org
2018-07-30 14:51:40 +01:00
Peter Maydell
1a5182c0d2 target/arm: Escalate to correct HardFault when AIRCR.BFHFNMINS is set
When we escalate a v8M exception to HardFault, if AIRCR.BFHFNMINNS is
set then we need to decide whether it should become a secure HardFault
or a nonsecure HardFault. We should always escalate to the same
target security state as the original exception. The current code
tries to test this using the 'secure' bool, which is not right because
that flag indicates whether the target security state only for
banked exceptions; the effect was that we were incorrectly escalating
always-secure exceptions like SecureFault to a nonsecure HardFault.

Fix this by defining, logging and using a new 'targets_secure' bool
which tracks the condition we actually want.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180723123457.2038-1-peter.maydell@linaro.org
2018-07-24 11:43:08 +01:00
Thomas Huth
955cbc6b17 hw/arm/armv7: Fix crash when introspecting the "iotkit" device
QEMU currently crashes when introspecting the "iotkit" device and
runnint "info qtree" afterwards, e.g. when running QEMU like this:

echo "{'execute':'qmp_capabilities'} {'execute':'device-list-properties'," \
 "'arguments':{'typename':'iotkit'}}" "{'execute': 'human-monitor-command', " \
 "'arguments': {'command-line': 'info qtree'}}" | \
 aarch64-softmmu/qemu-system-aarch64 -M none,accel=qtest -qmp stdio

Use the new functions object_initialize_child() and sysbus_init_child_obj()
to make sure that all objects get cleaned up correctly when the instances
are destroyed.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 1531745974-17187-5-git-send-email-thuth@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-07-17 13:12:49 +01:00
Peter Maydell
95f875654a arm: Don't crash if user tries to use a Cortex-M CPU without an NVIC
The Cortex-M CPU and its NVIC are two intimately intertwined parts of
the same hardware; it is not possible to use one without the other.
Unfortunately a lot of our board models don't do any sanity checking
on the CPU type the user asks for, so a command line like
    qemu-system-arm -M versatilepb -cpu cortex-m3
will create an M3 without an NVIC, and coredump immediately.
In the other direction, trying a non-M-profile CPU in an M-profile
board won't blow up, but doesn't do anything useful either:
    qemu-system-arm -M lm3s6965evb -cpu arm926

Add some checking in the NVIC and CPU realize functions that the
user isn't trying to use an NVIC without an M-profile CPU or
an M-profile CPU without an NVIC, so we can produce a helpful
error message rather than a core dump.

Fixes: https://bugs.launchpad.net/qemu/+bug/1766896
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180601160355.15393-1-peter.maydell@linaro.org
2018-06-15 15:23:34 +01:00
Peter Maydell
12fbf1a163 hw/intc/armv7m_nvic: Fix byte-to-interrupt number conversions
In many of the NVIC registers relating to interrupts, we
have to convert from a byte offset within a register set
into the number of the first interrupt which is affected.
We were getting this wrong for:
 * reads of NVIC_ISPR<n>, NVIC_ISER<n>, NVIC_ICPR<n>, NVIC_ICER<n>,
   NVIC_IABR<n> -- in all these cases we were missing the "* 8"
   needed to convert from the byte offset to the interrupt number
   (since all these registers use one bit per interrupt)
 * writes of NVIC_IPR<n> had the opposite problem of a spurious
   "* 8" (since these registers use one byte per interrupt)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180209165810.6668-9-peter.maydell@linaro.org
2018-02-15 18:29:49 +00:00
Peter Maydell
24ac0fb129 hw/intc/armv7m_nvic: Implement SCR
We were previously making the system control register (SCR)
just RAZ/WI. Although we don't implement the functionality
this register controls, we should at least provide the state,
including the banked state for v8M.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180209165810.6668-7-peter.maydell@linaro.org
2018-02-15 18:29:49 +00:00
Peter Maydell
43bbce7fbe hw/intc/armv7m_nvic: Implement cache ID registers
M profile cores have a similar setup for cache ID registers
to A profile:
 * Cache Level ID Register (CLIDR) is a fixed value
 * Cache Type Register (CTR) is a fixed value
 * Cache Size ID Registers (CCSIDR) are a bank of registers;
   which one you see is selected by the Cache Size Selection
   Register (CSSELR)

The only difference is that they're in the NVIC memory mapped
register space rather than being coprocessor registers.
Implement the M profile view of them.

Since neither Cortex-M3 nor Cortex-M4 implement caches,
we don't need to update their init functions and can leave
the ctr/clidr/ccsidr[] fields in their ARMCPU structs at zero.
Newer cores (like the Cortex-M33) will want to be able to
set these ID registers to non-zero values, though.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180209165810.6668-6-peter.maydell@linaro.org
2018-02-15 18:29:49 +00:00
Peter Maydell
ae7c5c855b hw/intc/armv7m_nvic: Implement v8M CPPWR register
The Coprocessor Power Control Register (CPPWR) is new in v8M.
It allows software to control whether coprocessors are allowed
to power down and lose their state. QEMU doesn't have any
notion of power control, so we choose the IMPDEF option of
making the whole register RAZ/WI (indicating that no coprocessors
can ever power down and lose state).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180209165810.6668-5-peter.maydell@linaro.org
2018-02-15 18:29:49 +00:00
Peter Maydell
e8ab26c484 hw/intc/armv7m_nvic: Implement M profile cache maintenance ops
For M profile cores, cache maintenance operations are done by
writing to special registers in the system register space.
For QEMU, cache operations are always NOPs, since we don't
implement the cache. Implementing these explicitly avoids
a spurious LOG_GUEST_ERROR when the guest uses them.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180209165810.6668-4-peter.maydell@linaro.org
2018-02-15 18:29:49 +00:00
Peter Maydell
4f2eff36ad hw/intc/armv7m_nvic: Fix ICSR PENDNMISET/CLR handling
The PENDNMISET/CLR bits in the ICSR should be RAZ/WI from
NonSecure state if the AIRCR.BFHFNMINS bit is zero. We had
misimplemented this as making the bits RAZ/WI from both
Secure and NonSecure states. Fix this bug by checking
attrs.secure so that Secure code can pend and unpend NMIs.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180209165810.6668-3-peter.maydell@linaro.org
2018-02-15 18:29:49 +00:00
Peter Maydell
5a53e2c1dc hw/intc/armv7m_nvic: Don't hardcode M profile ID registers in NVIC
Instead of hardcoding the values of M profile ID registers in the
NVIC, use the fields in the CPU struct. This will allow us to
give different M profile CPU types different ID register values.

This commit includes the addition of the missing ID_ISAR5,
which exists as RES0 in both v7M and v8M.

(The values of the ID registers might be wrong for the M4 --
this commit leaves the behaviour there unchanged.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180209165810.6668-2-peter.maydell@linaro.org
2018-02-15 18:29:49 +00:00
Peter Maydell
6c94851881 target/arm: Split "get pending exception info" from "acknowledge it"
Currently armv7m_nvic_acknowledge_irq() does three things:
 * make the current highest priority pending interrupt active
 * return a bool indicating whether that interrupt is targeting
   Secure or NonSecure state
 * implicitly tell the caller which is the highest priority
   pending interrupt by setting env->v7m.exception

We need to split these jobs, because v7m_exception_taken()
needs to know whether the pending interrupt targets Secure so
it can choose to stack callee-saves registers or not, but it
must not make the interrupt active until after it has done
that stacking, in case the stacking causes a derived exception.
Similarly, it needs to know the number of the pending interrupt
so it can read the correct vector table entry before the
interrupt is made active, because vector table reads might
also cause a derived exception.

Create a new armv7m_nvic_get_pending_irq_info() function which simply
returns information about the highest priority pending interrupt, and
use it to rearrange the v7m_exception_taken() code so we don't
acknowledge the exception until we've done all the things which could
possibly cause a derived exception.

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: 1517324542-6607-3-git-send-email-peter.maydell@linaro.org
2018-02-09 10:40:27 +00:00
Peter Maydell
5ede82b8cc target/arm: Add armv7m_nvic_set_pending_derived()
In order to support derived exceptions (exceptions generated in
the course of trying to take an exception), we need to be able
to handle prioritizing whether to take the original exception
or the derived exception.

We do this by introducing a new function
armv7m_nvic_set_pending_derived() which the exception-taking code in
helper.c will call when a derived exception occurs.  Derived
exceptions are dealt with mostly like normal pending exceptions, so
we share the implementation with the armv7m_nvic_set_pending()
function.

Note that the way we structure this is significantly different
from the v8M Arm ARM pseudocode: that does all the prioritization
logic in the DerivedLateArrival() function, whereas we choose to
let the existing "identify highest priority exception" logic
do the prioritization for us. The effect is the same, though.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1517324542-6607-2-git-send-email-peter.maydell@linaro.org
2018-02-09 10:40:27 +00:00
Peter Maydell
4b9774ef48 hw/intc/armv7m: Support byte and halfword accesses to CFSR
The Configurable Fault Status Register for ARMv7M and v8M is
supposed to be byte and halfword accessible, but we were only
implementing word accesses. Add support for the other access
sizes, which are used by the Zephyr RTOS.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reported-by: Andy Gross <andy.gross@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1512742372-31517-1-git-send-email-peter.maydell@linaro.org
2018-01-16 13:28:09 +00:00
Peter Maydell
27f26bfed9 nvic: Make systick banked
For the v8M security extension, there should be two systick
devices, which use separate banked systick exceptions. The
register interface is banked in the same way as for other
banked registers, including the existence of an NS alias
region for secure code to access the nonsecure timer.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1512154296-5652-3-git-send-email-peter.maydell@linaro.org
2017-12-13 17:59:26 +00:00
Peter Maydell
62f018482c nvic: Make nvic_sysreg_ns_ops work with any MemoryRegion
Generalize nvic_sysreg_ns_ops so that we can pass it an
arbitrary MemoryRegion which it will use as the underlying
register implementation to apply the NS-alias behaviour
to. We'll want this so we can do the same with systick.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1512154296-5652-2-git-send-email-peter.maydell@linaro.org
2017-12-13 17:59:26 +00:00
Peter Maydell
2b75ef01ca nvic: Fix ARMv7M MPU_RBAR reads
Fix an incorrect mask expression in the handling of v7M MPU_RBAR
reads that meant that we would always report the ADDR field as zero.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1509732813-22957-1-git-send-email-peter.maydell@linaro.org
2017-11-20 13:39:48 +00:00
Peter Maydell
cf5f7937b0 nvic: Fix miscalculation of offsets into ITNS array
This calculation of the first exception vector in
the ITNS<n> register being accessed:
        int startvec = 32 * (offset - 0x380) + NVIC_FIRST_IRQ;

is incorrect, because offset is in bytes, so we only want
to multiply by 8.

Spotted by Coverity (CID 1381484, CID 1381488), though it is
not correct that it actually overflows the buffer, because
we have a 'startvec + i < s->num_irq' guard.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507650856-11718-1-git-send-email-peter.maydell@linaro.org
2017-10-12 16:33:16 +01:00
Peter Maydell
a94bb9cd58 nvic: Add missing 'break'
Coverity points out that we forgot the 'break' for
the SAU_CTRL write case (CID1381683). This has
no actual visible consequences because it happens
that the following case is effectively a no-op.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1507742676-9908-1-git-send-email-peter.maydell@linaro.org
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-12 13:24:39 +01:00
Peter Maydell
04829ce334 nvic: Add missing code for writing SHCSR.HARDFAULTPENDED bit
When we added support for the new SHCSR bits in v8M in commit
437d59c17e the code to support writing to the new HARDFAULTPENDED
bit was accidentally only added for non-secure writes; the
secure banked version of the bit should also be writable.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1506092407-26985-21-git-send-email-peter.maydell@linaro.org
2017-10-06 16:46:49 +01:00
Peter Maydell
9901c576f6 nvic: Implement Security Attribution Unit registers
Implement the register interface for the SAU: SAU_CTRL,
SAU_TYPE, SAU_RNR, SAU_RBAR and SAU_RLAR. None of the
actual behaviour is implemented here; registers just
read back as written.

When the CPU definition for Cortex-M33 is eventually
added, its initfn will set cpu->sau_sregion, in the same
way that we currently set cpu->pmsav7_dregion for the
M3 and M4.

Number of SAU regions is typically a configurable
CPU parameter, but this patch doesn't provide a
QEMU CPU property for it. We can easily add one when
we have a board that requires it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1506092407-26985-14-git-send-email-peter.maydell@linaro.org
2017-10-06 16:46:49 +01:00
Peter Maydell
bed079da04 target/arm: Add new-in-v8M SFSR and SFAR
Add the new M profile Secure Fault Status Register
and Secure Fault Address Register.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1506092407-26985-10-git-send-email-peter.maydell@linaro.org
2017-10-06 16:46:48 +01:00
Peter Maydell
de2db7ec89 target/arm: Prepare for CONTROL.SPSEL being nonzero in Handler mode
In the v7M architecture, there is an invariant that if the CPU is
in Handler mode then the CONTROL.SPSEL bit cannot be nonzero.
This in turn means that the current stack pointer is always
indicated by CONTROL.SPSEL, even though Handler mode always uses
the Main stack pointer.

In v8M, this invariant is removed, and CONTROL.SPSEL may now
be nonzero in Handler mode (though Handler mode still always
uses the Main stack pointer). In preparation for this change,
change how we handle this bit: rename switch_v7m_sp() to
the now more accurate write_v7m_control_spsel(), and make it
check both the handler mode state and the SPSEL bit.

Note that this implicitly changes the point at which we switch
active SP on exception exit from before we pop the exception
frame to after it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1506092407-26985-4-git-send-email-peter.maydell@linaro.org
2017-10-06 16:46:47 +01:00
Peter Maydell
8ff26a3344 nvic: Clear the vector arrays and prigroup on reset
Reset for devices does not include an automatic clear of the
device state (unlike CPU state, where most of the state
structure is cleared to zero). Add some missing initialization
of NVIC state that meant that the device was left in the wrong
state if the guest did a warm reset.

(In particular, since we were resetting the computed state like
s->exception_prio but not all the state it was computed
from like s->vectors[x].active, the NVIC wound up in an
inconsistent state that could later trigger assertion failures.)

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: 1506092407-26985-2-git-send-email-peter.maydell@linaro.org
2017-10-06 16:46:47 +01:00
Peter Maydell
5cb18069d7 nvic: Support banked exceptions in acknowledge and complete
Update armv7m_nvic_acknowledge_irq() and armv7m_nvic_complete_irq()
to handle banked exceptions:
 * acknowledge needs to use the correct vector, which may be
   in sec_vectors[]
 * acknowledge needs to return to its caller whether the
   exception should be taken to secure or non-secure state
 * complete needs its caller to tell it whether the exception
   being completed is a secure one or not

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-20-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
437d59c17e nvic: Make SHCSR banked for v8M
Handle banking of SHCSR: some register bits are banked between
Secure and Non-Secure, and some are only accessible to Secure.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-19-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
3f1e0eb7c3 nvic: Make ICSR banked for v8M
The ICSR NVIC register is banked for v8M. This doesn't
require any new state, but it does mean that some bits
are controlled by BFHNFNMINS and some bits must work
with the correct banked exception. There is also a new
in v8M PENDNMICLR bit.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-18-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
5d4791991d target/arm: Handle banking in negative-execution-priority check in cpu_mmu_index()
Now that we have a banked FAULTMASK register and banked exceptions,
we can implement the correct check in cpu_mmu_index() for whether
the MPU_CTRL.HFNMIENA bit's effect should apply. This bit causes
handlers which have requested a negative execution priority to run
with the MPU disabled. In v8M the test has to check this for the
current security state and so takes account of banking.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-17-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
49c80c380d nvic: Handle v8M changes in nvic_exec_prio()
Update nvic_exec_prio() to support the v8M changes:
 * BASEPRI, FAULTMASK and PRIMASK are all banked
 * AIRCR.PRIS can affect NS priorities
 * AIRCR.BFHFNMINS affects FAULTMASK behaviour

These changes mean that it's no longer possible to
definitely say that if FAULTMASK is set it overrides
PRIMASK, and if PRIMASK is set it overrides BASEPRI
(since if PRIMASK_NS is set and AIRCR.PRIS is set then
whether that 0x80 priority should take effect or the
priority in BASEPRI_S depends on the value of BASEPRI_S,
for instance). So we switch to the same approach used
by the pseudocode of working through BASEPRI, PRIMASK
and FAULTMASK and overriding the previous values if
needed.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-16-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
7208b426c7 nvic: Disable the non-secure HardFault if AIRCR.BFHFNMINS is clear
If AIRCR.BFHFNMINS is clear, then although NonSecure HardFault
can still be pended via SHCSR.HARDFAULTPENDED it mustn't actually
preempt execution. The simple way to achieve this is to clear the
enable bit for it, since the enable bit isn't guest visible.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-15-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
331f4bae6c nvic: Implement v8M changes to fixed priority exceptions
In v7M, the fixed-priority exceptions are:
 Reset: -3
 NMI: -2
 HardFault: -1

In v8M, this changes because Secure HardFault may need
to be prioritised above NMI:
 Reset: -4
 Secure HardFault if AIRCR.BFHFNMINS == 1: -3
 NMI: -2
 Secure HardFault if AIRCR.BFHFNMINS == 0: -1
 NonSecure HardFault: -1

Make these changes, including support for changing the
priority of Secure HardFault as AIRCR.BFHFNMINS changes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-14-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
94a34abe32 nvic: In escalation to HardFault, support HF not being priority -1
When escalating to HardFault, we must go into Lockup if we
can't take the synchronous HardFault because the current
execution priority is already at or below the priority of
HardFault. In v7M HF is always priority -1 so a simple < 0
comparison sufficed; in v8M the priority of HardFault can
vary depending on whether it is a Secure or NonSecure
HardFault, so we must check against the priority of the
HardFault exception vector we're about to use.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-13-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
80ac239035 nvic: Compare group priority for escalation to HF
In armv7m_nvic_set_pending() we have to compare the
priority of an exception against the execution priority
to decide whether it needs to be escalated to HardFault.
In the specification this is a comparison against the
exception's group priority; for v7M we implemented it
as a comparison against the raw exception priority
because the two comparisons will always give the
same answer. For v8M the existence of AIRCR.PRIS and
the possibility of different PRIGROUP values for secure
and nonsecure exceptions means we need to explicitly
calculate the vector's group priority for this check.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-12-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
e6a0d3500d nvic: Make SHPR registers banked
Make the set_prio() function take a bool indicating
whether to pend the secure or non-secure version of a banked
interrupt, and use this to implement the correct banking
semantics for the SHPR registers.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-11-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
2fb50a3340 nvic: Make set_pending and clear_pending take a secure parameter
Make the armv7m_nvic_set_pending() and armv7m_nvic_clear_pending()
functions take a bool indicating whether to pend the secure
or non-secure version of a banked interrupt, and update the
callsites accordingly.

In most callsites we can simply pass the correct security
state in; in a couple of cases we use TODO comments to indicate
that we will return the code in a subsequent commit.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-10-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
ff96c64aec nvic: Handle banked exceptions in nvic_recompute_state()
Update the nvic_recompute_state() code to handle the security
extension and its associated banked registers.

Code that uses the resulting cached state (ie the irq
acknowledge and complete code) will be updated in a later
commit.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-9-git-send-email-peter.maydell@linaro.org
2017-09-21 16:31:09 +01:00
Peter Maydell
e1be0a576b nvic: Implement NVIC_ITNS<n> registers
For v8M, the NVIC has a new set of registers per interrupt,
NVIC_ITNS<n>. These determine whether the interrupt targets Secure
or Non-secure state. Implement the register read/write code for
these, and make them cause NVIC_IABR, NVIC_ICER, NVIC_ISER,
NVIC_ICPR, NVIC_IPR and NVIC_ISPR to RAZ/WI for non-secure
accesses to fields corresponding to interrupts which are
configured to target secure state.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-8-git-send-email-peter.maydell@linaro.org
2017-09-21 16:29:27 +01:00
Peter Maydell
028b0da424 nvic: Make ICSR.RETTOBASE handle banked exceptions
Update the code in nvic_rettobase() so that it checks the
sec_vectors[] array as well as the vectors[] array if needed.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-7-git-send-email-peter.maydell@linaro.org
2017-09-21 16:29:27 +01:00
Peter Maydell
3b2e934463 nvic: Implement AIRCR changes for v8M
The Application Interrupt and Reset Control Register has some changes
for v8M:
 * new bits SYSRESETREQS, BFHFNMINS and PRIS: these all have
   real state if the security extension is implemented and otherwise
   are constant
 * the PRIGROUP field is banked between security states
 * non-secure code can be blocked from using the SYSRESET bit
   to reset the system if SYSRESETREQS is set

Implement the new state and the changes to register read and write.
For the moment we ignore the effects of the secure PRIGROUP.
We will implement the effects of PRIS and BFHFNMIS later.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-6-git-send-email-peter.maydell@linaro.org
2017-09-21 16:29:27 +01:00
Peter Maydell
5255fcf8e4 nvic: Add cached vectpending_prio state
Instead of looking up the pending priority
in nvic_pending_prio(), cache it in a new state struct
field. The calculation of the pending priority given
the interrupt number is more complicated in v8M with
the security extension, so the caching will be worthwhile.

This changes nvic_pending_prio() from returning a full
(group + subpriority) priority value to returning a group
priority. This doesn't require changes to its callsites
because we use it only in comparisons of the form
  execution_prio > nvic_pending_prio()
and execution priority is always a group priority, so
a test (exec prio > full prio) is true if and only if
(execprio > group_prio).

(Architecturally the expected comparison is with the
group priority for this sort of "would we preempt" test;
we were only doing a test with a full priority as an
optimisation to avoid the mask, which is possible
precisely because the two comparisons always give the
same answer.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-5-git-send-email-peter.maydell@linaro.org
2017-09-21 16:29:27 +01:00
Peter Maydell
e93bc2ac11 nvic: Add cached vectpending_is_s_banked state
With banked exceptions, just the exception number in
s->vectpending is no longer sufficient to uniquely identify
the pending exception. Add a vectpending_is_s_banked bool
which is true if the exception is using the sec_vectors[]
array.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1505240046-11454-4-git-send-email-peter.maydell@linaro.org
2017-09-21 16:29:23 +01:00
Peter Maydell
17906a162a nvic: Add banked exception states
For the v8M security extension, some exceptions must be banked
between security states. Add the new vecinfo array which holds
the state for the banked exceptions and migrate it if the
CPU the NVIC is attached to implements the security extension.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-21 16:28:59 +01:00
Peter Maydell
22a9c26af6 nvic: Don't apply group priority mask to negative priorities
In several places we were unconditionally applying the
nvic_gprio_mask() to a priority value. This is incorrect
if the priority is one of the fixed negative priority
values (for NMI and HardFault), so don't do it.

This bug would have caused both NMI and HardFault to be
considered as the same priority and so NMI wouldn't
correctly preempt HardFault.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505137930-13255-5-git-send-email-peter.maydell@linaro.org
2017-09-14 18:43:17 +01:00
Peter Maydell
334e8dad7a target/arm: Make CFSR register banked for v8M
Make the CFSR register banked if v8M security extensions are enabled.

Not all the bits in this register are banked: the BFSR
bits [15:8] are shared between S and NS, and we store them
in the NS copy of the register.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-19-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:54 +01:00
Peter Maydell
c51a5cfc9f target/arm: Make MMFAR banked for v8M
Make the MMFAR register banked if v8M security extensions are
enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-18-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:54 +01:00
Peter Maydell
9d40cd8a68 target/arm: Make CCR register banked for v8M
Make the CCR register banked if v8M security extensions are enabled.

This is slightly more complicated than the other "add banking"
patches because there is one bit in the register which is not
banked. We keep the live data in the NS copy of the register,
and adjust it on register reads and writes. (Since we don't
currently implement the behaviour that the bit controls, there
is nowhere else that needs to care.)

This patch includes the enforcement of the bits which are newly
RES1 in ARMv8M.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1503414539-28762-17-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:54 +01:00
Peter Maydell
ecf5e8eae8 target/arm: Make MPU_CTRL register banked for v8M
Make the MPU_CTRL register banked if v8M security extensions are
enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-16-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:53 +01:00
Peter Maydell
1bc04a8880 target/arm: Make MPU_RNR register banked for v8M
Make the MPU_RNR register banked if v8M security extensions are
enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-15-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:53 +01:00
Peter Maydell
62c58ee0b2 target/arm: Make MPU_RBAR, MPU_RLAR banked for v8M
Make the MPU registers MPU_MAIR0 and MPU_MAIR1 banked if v8M security
extensions are enabled.

We can freely add more items to vmstate_m_security without
breaking migration compatibility, because no CPU currently
has the ARM_FEATURE_M_SECURITY bit enabled and so this
subsection is not yet used by anything.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-14-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:53 +01:00
Peter Maydell
4125e6feb7 target/arm: Make MPU_MAIR0, MPU_MAIR1 registers banked for v8M
Make the MPU registers MPU_MAIR0 and MPU_MAIR1 banked if v8M security
extensions are enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-13-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:53 +01:00
Peter Maydell
45db7ba681 target/arm: Make VTOR register banked for v8M
Make the VTOR register banked if v8M security extensions are enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-12-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:53 +01:00
Peter Maydell
f104919d15 nvic: Add NS alias SCS region
For v8M the range 0xe002e000..0xe002efff is an alias region which
for secure accesses behaves like a NonSecure access to the main
SCS region. (For nonsecure accesses including when the security
extension is not implemented, it is RAZ/WI.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1503414539-28762-11-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:53 +01:00
Peter Maydell
42a6686b2f target/arm: Make FAULTMASK register banked for v8M
Make the FAULTMASK register banked if v8M security extensions are enabled.

Note that we do not yet implement the functionality of the new
AIRCR.PRIS bit (which allows the effect of the NS copy of FAULTMASK to
be restricted).

This patch includes the code to determine for v8M which copy
of FAULTMASK should be updated on exception exit; further
changes will be required to the exception exit code in general
to support v8M, so this is just a small piece of that.

The v8M ARM ARM introduces a notation where individual paragraphs
are labelled with R (for rule) or I (for information) followed
by a random group of subscript letters. In comments where we want
to refer to a particular part of the manual we use this convention,
which should be more stable across document revisions than using
section or page numbers.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-9-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:52 +01:00
Peter Maydell
6d80483419 target/arm: Make PRIMASK register banked for v8M
Make the PRIMASK register banked if v8M security extensions are enabled.

Note that we do not yet implement the functionality of the new
AIRCR.PRIS bit (which allows the effect of the NS copy of PRIMASK to
be restricted).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-8-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:52 +01:00
Peter Maydell
acf949411f target/arm: Make BASEPRI register banked for v8M
Make the BASEPRI register banked if v8M security extensions are enabled.

Note that we do not yet implement the functionality of the new
AIRCR.PRIS bit (which allows the effect of the NS copy of BASEPRI to
be restricted).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-7-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:52 +01:00
Peter Maydell
0e1a46bbd2 target/arm: Implement ARMv8M's PMSAv8 registers
As part of ARMv8M, we need to add support for the PMSAv8 MPU
architecture.

PMSAv8 differs from PMSAv7 both in register/data layout (for instance
using base and limit registers rather than base and size) and also in
behaviour (for example it does not have subregions); rather than
trying to wedge it into the existing PMSAv7 code and data structures,
we define separate ones.

This commit adds the data structures which hold the state for a
PMSAv8 MPU and the register interface to it.  The implementation of
the MPU behaviour will be added in a subsequent commit.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-2-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:51 +01:00
Peter Maydell
eb578a2394 nvic: Implement "user accesses BusFault" SCS region behaviour
The ARMv7M architecture specifies that most of the addresses in the
PPB region (which includes the NVIC, systick and system registers)
are not accessible to unprivileged accesses, which should
BusFault with a few exceptions:
 * the STIR is configurably user-accessible
 * the ITM (which we don't implement at all) is always
   user-accessible

Implement this by switching the register access functions
to the _with_attrs scheme that lets us distinguish user
mode accesses.

This allows us to pull the handling of the CCR.USERSETMPEND
flag up to the level where we can make it generate a BusFault
as it should for non-permitted accesses.

Note that until the core ARM CPU code implements turning
MEMTX_ERROR into a BusFault the registers will continue to
act as RAZ/WI to user accesses.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1501692241-23310-16-git-send-email-peter.maydell@linaro.org
2017-09-04 15:21:53 +01:00
Peter Maydell
d2db1de6ff armv7m_nvic.h: Move from include/hw/arm to include/hw/intc
The armv7m_nvic.h header file was accidentally placed in
include/hw/arm; move it to include/hw/intc to match where
its corresponding .c file lives.

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>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1501692241-23310-15-git-send-email-peter.maydell@linaro.org
2017-09-04 15:21:53 +01:00
Peter Maydell
e6ae5981ea target/arm: Don't store M profile PRIMASK and FAULTMASK in daif
We currently store the M profile CPU register state PRIMASK and
FAULTMASK in the daif field of the CPU state in its I and F
bits. This is a legacy from the original implementation, which
tried to share the cpu_exec_interrupt code between A profile
and M profile. We've since separated out the two cases because
they are significantly different, so now there is no common
code between M and A profile which looks at env->daif: all the
uses are either in A-only or M-only code paths. Sharing the state
fields now is just confusing, and will make things awkward
when we implement v8M, where the PRIMASK and FAULTMASK
registers are banked between security states.

Switch M profile over to using v7m.faultmask and v7m.primask
fields for these registers.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1501692241-23310-10-git-send-email-peter.maydell@linaro.org
2017-09-04 15:21:52 +01:00
Peter Maydell
79c857a35f hw/intc/armv7m_nvic.c: Remove out of date comment
Remove an out of date comment which says there's only one
item in the NVIC container region -- we put systick into its
own device object a while back and so now there are two
things in the container.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1501692241-23310-6-git-send-email-peter.maydell@linaro.org
2017-09-04 15:21:52 +01:00
Peter Maydell
8531eb4f61 target/arm: Rename cp15.c6_rgnr to pmsav7.rnr
Almost all of the PMSAv7 state is in the pmsav7 substruct of
the ARM CPU state structure. The exception is the region
number register, which is in cp15.c6_rgnr. This exception
is a bit odd for M profile, which otherwise generally does
not store state in the cp15 substruct.

Rename cp15.c6_rgnr to pmsav7.rnr accordingly.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1501153150-19984-4-git-send-email-peter.maydell@linaro.org
2017-07-31 13:09:52 +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
Peter Maydell
ff68dacbc7 armv7m: Split systick out from NVIC
The SysTick timer isn't really part of the NVIC proper;
we just modelled it that way back when we couldn't
easily have devices that only occupied a small chunk
of a memory region. Split it out into its own device.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1487604965-23220-10-git-send-email-peter.maydell@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 16:18:49 +00:00
Peter Maydell
98957a94ef armv7m: Make NVIC expose a memory region rather than mapping itself
Make the NVIC device expose a memory region for its users
to map, rather than mapping itself into the system memory
space on realize, and get the one user (the ARMv7M object)
to do this.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1487604965-23220-7-git-send-email-peter.maydell@linaro.org
2017-02-28 16:18:49 +00:00
Peter Maydell
6bf436cf9d armv7m: Move NVICState struct definition into header
Move the NVICState struct definition into a header, so we can
embed it into other QOM objects like SoCs.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1487604965-23220-3-git-send-email-peter.maydell@linaro.org
2017-02-28 16:18:49 +00:00
Peter Maydell
5db53e353d armv7m: Allow SHCSR writes to change pending and active bits
Implement the NVIC SHCSR write behaviour which allows pending and
active status of some exceptions to be changed.

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
Michael Davidsaver
14790f730a armv7m: VECTCLRACTIVE and VECTRESET are UNPREDICTABLE
The VECTCLRACTIVE and VECTRESET bits in the AIRCR are both
documented as UNPREDICTABLE if you write a 1 to them when
the processor is not halted in Debug state (ie stopped
and under the control of an external JTAG debugger).
Since we don't implement Debug state or emulated JTAG
these bits are always UNPREDICTABLE for us. Instead of
logging them as unimplemented we can simply log writes
as guest errors and ignore them.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
[PMM: change extracted from another patch; commit message
 constructed from scratch]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:18 +00:00
Peter Maydell
a5d8235545 armv7m: Remove unused armv7m_nvic_acknowledge_irq() return value
Having armv7m_nvic_acknowledge_irq() return the new value of
env->v7m.exception and its one caller assign the return value
back to env->v7m.exception is pointless. Just make the return
type void instead.

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
Michael Davidsaver
a73c98e159 armv7m: Escalate exceptions to HardFault if necessary
The v7M exception architecture requires that if a synchronous
exception cannot be taken immediately (because it is disabled
or at too low a priority) then it should be escalated to
HardFault (and the HardFault exception is then taken).
Implement this escalation logic.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
[PMM: extracted from another patch]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:17 +00:00
Peter Maydell
7ecdaa4a96 armv7m: Fix condition check for taking exceptions
The M profile condition for when we can take a pending exception or
interrupt is not the same as that for A/R profile.  The code
originally copied from the A/R profile version of the
cpu_exec_interrupt function only worked by chance for the
very simple case of exceptions being masked by PRIMASK.
Replace it with a call to a function in the NVIC code that
correctly compares the priority of the pending exception
against the current execution priority of the CPU.

[Michael Davidsaver's patchset had a patch to do something
similar but the implementation ended up being a rewrite.]

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:17 +00:00
Michael Davidsaver
da6d674e50 armv7m: Rewrite NVIC to not use any GIC code
Despite some superficial similarities of register layout, the
M-profile NVIC is really very different from the A-profile GIC.
Our current attempt to reuse the GIC code means that we have
significant bugs in our NVIC.

Implement the NVIC as an entirely separate device, to give
us somewhere we can get the behaviour correct.

This initial commit does not attempt to implement exception
priority escalation, since the GIC-based code didn't either.
It does fix a few bugs in passing:
 * ICSR.RETTOBASE polarity was wrong and didn't account for
   internal exceptions
 * ICSR.VECTPENDING was 16 too high if the pending exception
   was for an external interrupt
 * UsageFault, BusFault and MemFault were not disabled on reset
   as they are supposed to be

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
[PMM: reworked, various bugs and stylistic cleanups]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:17 +00:00
Peter Maydell
1004102a77 armv7m: Implement reading and writing of PRIGROUP
Add a state field for the v7M PRIGROUP register and implent
reading and writing it. The current NVIC doesn't honour
the values written, but the new version will.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:16 +00:00
Peter Maydell
f797c07507 armv7m: Rename nvic_state to NVICState
Rename the nvic_state struct to NVICState, to match
our naming conventions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:16 +00:00
Michael Davidsaver
bdd04fc76a armv7m: Honour CCR.USERSETMPEND
The CCR.USERSETMPEND bit has to be set to permit unprivileged code to
write to the Software Triggered Interrupt register; honour this bit
rather than letting any code write to the register.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1485285380-10565-9-git-send-email-peter.maydell@linaro.org
[PMM: Tweak commit message, comment, phrasing of condition]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-01-27 15:29:08 +00:00
Michael Davidsaver
e6b332097d armv7m: implement CCR, CFSR, HFSR, DFSR, BFAR, and MMFAR
Implement the v7M system registers CCR, CFSR, HFSR, DFSR, BFAR and
MMFAR.  For the moment these simply read as written (with some basic
handling of RAZ/WI bits and W1C semantics).

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1485285380-10565-5-git-send-email-peter.maydell@linaro.org
[PMM: drop warning about setting unimplemented CCR bits;
 tweak commit message; add DFSR]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-01-27 15:29:08 +00:00
Michael Davidsaver
d713ea6c46 armv7m_nvic: keep a pointer to the CPU
Many NVIC operations access the CPU state, so store a pointer in
struct nvic_state rather than fetching it via qemu_get_cpu() every
time we need it.

As with the arm_gicv3_common code, we currently just call
qemu_get_cpu() in the NVIC's realize method, but in future we might
want to use a QOM property to pass the CPU to the NVIC.

This imposes an ordering requirement that the CPU is
realized before the NVIC, but that is always true since
both are dealt with in armv7m_init().

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1485285380-10565-3-git-send-email-peter.maydell@linaro.org
[PMM: Use qemu_get_cpu(0) rather than first_cpu; expand
 commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-01-27 15:29:08 +00:00
Andrey Smirnov
a19861666b armv7m_nvic: Use qemu_get_cpu(0) instead of current_cpu
Starting QEMU with -S results in current_cpu containing its initial
value of NULL. It is however possible to connect to such QEMU instance
and query various CPU registers, one example being CPUID, and doing that
results in QEMU segfaulting.

Using qemu_get_cpu(0) seem reasonable enough given that ARMv7M
architecture is a single core architecture.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-07-04 13:15:22 +01:00
Paolo Bonzini
03dd024ff5 hw: explicitly include qemu/log.h
Move the inclusion out of hw/hw.h, most files do not need it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:29 +02:00
Paolo Bonzini
33c11879fd qemu-common: push cpu.h inclusion out of qemu-common.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:29 +02:00
Paolo Bonzini
4771d756f4 hw: explicitly include qemu-common.h and cpu.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Markus Armbruster
da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Peter Maydell
8ef94f0bc9 arm: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-13-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:23 +00:00
Michael Davidsaver
e192becdc7 armv7-m: Implement SYSRESETREQ
Implement the SYSRESETREQ bit of the AIRCR register
for armv7-m (ie. cortex-m3) to trigger a GPIO out.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Reviewed-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-11-03 13:49:41 +00:00
Peter Maydell
b06c262b45 armv7m_nvic: Implement ICSR without using internal GIC state
Change the implementation of the Interrupt Control and State Register
in the v7M NVIC to not use the running_irq and last_active internal
state fields in the GIC. These fields don't correspond to state in
a real GIC and will be removed soon.
The changes to the ICSR are:
 * the VECTACTIVE field is documented as identical to the IPSR[8:0]
   field, so implement it that way
 * implement RETTOBASE via looking at the active state bits

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1438089748-5528-2-git-send-email-peter.maydell@linaro.org
2015-09-08 17:38:42 +01:00
Fabian Aggeler
c5619bf9e8 hw/intc/arm_gic: Change behavior of IAR writes
Grouping (GICv2) and Security Extensions change the behavior of IAR
reads. Acknowledging Group0 interrupts is only allowed from Secure
state and acknowledging Group1 interrupts from Secure state is only
allowed if AckCtl bit is set.

Signed-off-by: Fabian Aggeler <aggelerf@ethz.ch>
Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1430502643-25909-14-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-14-git-send-email-greg.bellows@linaro.org
[PMM: simplify significantly by reusing the existing
 gic_get_current_pending_irq() rather than reimplementing the
 same logic here]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-05-12 11:57:18 +01:00
Fabian Aggeler
f9c6a7f139 hw/intc/arm_gic: Change behavior of EOIR writes
Grouping (GICv2) and Security Extensions change the behavior of EOIR
writes. Completing Group0 interrupts is only allowed from Secure state.

Signed-off-by: Fabian Aggeler <aggelerf@ethz.ch>
Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1430502643-25909-13-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-13-git-send-email-greg.bellows@linaro.org
[PMM: Rather than go to great lengths to ignore the UNPREDICTABLE case
 of a Secure EOI of a Group1 (NS) irq with AckCtl == 0, we just let
 it fall through; add a comment about it.]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-05-12 11:57:18 +01:00
Fabian Aggeler
3295186083 hw/intc/arm_gic: Make ICCICR/GICC_CTLR banked
ICCICR/GICC_CTLR is banked in GICv1 implementations with Security
Extensions or in GICv2 in independent from Security Extensions.
This makes it possible to enable forwarding of interrupts from
the CPU interfaces to the connected processors for Group0 and Group1.

We also allow to set additional bits like AckCtl and FIQEn by changing
the type from bool to uint32. Since the field does not only store the
enable bit anymore and since we are touching the vmstate, we use the
opportunity to rename the field to cpu_ctlr.

Signed-off-by: Fabian Aggeler <aggelerf@ethz.ch>
Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1430502643-25909-9-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-9-git-send-email-greg.bellows@linaro.org
[PMM: rewrote to store state in a single uint32_t rather than
 keeping the NS and S banked variants separate; this considerably
 simplifies the get/set functions]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-05-12 11:57:17 +01:00
Fabian Aggeler
679aa175e8 hw/intc/arm_gic: Make ICDDCR/GICD_CTLR banked
ICDDCR/GICD_CTLR is banked if the GIC has the security extensions,
and the S (or only) copy has separate enable bits for Group0 and
Group1 enable if the GIC implements interrupt groups.

EnableGroup0 (Bit [1]) in GICv1 is architecturally IMPDEF. Since this
bit (Enable Non-secure) is present in the integrated GIC of the Cortex-A9
MPCore, we support this bit in our GICv1 implementation too.

Signed-off-by: Fabian Aggeler <aggelerf@ethz.ch>
Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1430502643-25909-7-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-8-git-send-email-greg.bellows@linaro.org
[PMM: rewritten to store the state in a single s->ctlr uint32,
 with the NS register handled as an alias of bit 1 in that value;
 added vmstate version bump]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-05-12 11:57:17 +01:00
Adrian Huang
165cdaf857 armv7m_nvic: systick: Reload the RELOAD value and count down only if ENABLE bit is set
Consider the following pseudo code to configure SYSTICK (The
recommended programming sequence from "the definitive guide to the
arm cortex-m3"):
    SYSTICK Reload Value Register = 0xffff
    SYSTICK Current Value Register = 0
    SYSTICK Control and Status Register = 0x7

The pseudo code "SYSTICK Current Value Register = 0" leads to invoking
systick_reload(). As a consequence, the systick.tick member is updated
and the systick timer starts to count down when the ENABLE bit of
SYSTICK Control and Status Register is cleared.

The worst case is that: during the system initialization, the reset
value of the SYSTICK Control and Status Register is 0x00000000.
When the code "SYSTICK Current Value Register = 0" is executed, the
systick.tick member is accumulated with "(s->systick.reload + 1) *
systick_scale(s)". The systick_scale() gets the external_ref_clock
scale because the CLKSOURCE bit of the SYSTICK Control and Status
Register is cleared. This is the incorrect behavior because of the
code "SYSTICK Control and Status Register = 0x7". Actually, we want
the processor clock instead of the external reference clock.

This incorrect behavior defers the generation of the first interrupt.

The patch fixes the above-mentioned issue by setting the systick.tick
member and modifying the systick timer only if the ENABLE bit of
the SYSTICK Control and Status Register is set.

In addition, the Cortex-M3 Devices Generic User Guide mentioned that
"When ENABLE is set to 1, the counter loads the RELOAD value from the
SYST RVR register and then counts down". This patch adheres to the
statement of the user guide.

Signed-off-by: Adrian Huang <adrianhuang0701@gmail.com>
Reviewed-by: Jim Huang <jserv.tw@gmail.com>
[PMM: minor tweak to comment text]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-05-12 11:57:16 +01:00
Paolo Bonzini
e720677e32 vmstate: accept QEMUTimer in VMSTATE_TIMER*, add VMSTATE_TIMER_PTR*
Old users of VMSTATE_TIMER* are mechanically changed to VMSTATE_TIMER_PTR
variants.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-26 12:22:44 +01:00
KONRAD Frederic
7b95a50858 arm_gic: remove unused parameter.
This removes num_irq parameter from gic_init_irqs_and_distributor as it is not
used.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1412859651-15060-1-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-10-24 12:19:11 +01:00
Oran Avraham
b6fb3a89e3 armv7m_nvic: fix AIRCR implementation
The returned reset value was wrong (off by one zero nibble), and
qemu didn't log unimplemented writes to the PRIGROUP field.

Signed-off-by: Oran Avraham <oranav@gmail.com>
Message-id: 1403010447-4627-1-git-send-email-oranav@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-06-19 18:33:05 +01:00
Juan Quintela
8f1e884b38 savevm: Remove all the unneeded version_minimum_id_old (arm)
After commit 767adce2d, they are redundant.  This way we don't assign them
except when needed.  Once there, there were lots of cases where the ".fields"
indentation was wrong:

     .fields = (VMStateField []) {
and
     .fields =      (VMStateField []) {

Change all the combinations to:

     .fields = (VMStateField[]){

The biggest problem (apart from aesthetics) was that checkpatch complained
when we copy&pasted the code from one place to another.

Signed-off-by: Juan Quintela <quintela@redhat.com>
[PMM: fixed minor conflict, corrected commit message typos]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-05-13 16:09:35 +01:00
Markus Armbruster
0175ba109e arm: Clean up fragile use of error_is_set() in realize() methods
Using error_is_set(ERRP) to find out whether a function failed is
either wrong, fragile, or unnecessarily opaque.  It's wrong when ERRP
may be null, because errors go undetected when it is.  It's fragile
when proving ERRP non-null involves a non-local argument.  Else, it's
unnecessarily opaque (see commit 84d18f0).

I guess the error_is_set(errp) in the DeviceClass realize() methods
are merely fragile right now, because I can't find a call chain that
passes a null errp argument.

Make the code more robust and more obviously correct: receive the
error in a local variable, then propagate it through the parameter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-05-05 19:08:49 +02:00
Rabin Vincent
e3da9921eb armv7m_nvic: fix CPUID Base Register
cp15.c0_cpuid is never initialized for ARMv7-M; take the value directly
from cpu->midr instead.

Signed-off-by: Rabin Vincent <rabin@rab.in>
Message-id: 1398036308-32166-1-git-send-email-rabin@rab.in
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-05-01 15:24:44 +01:00