This patch fixes so that gic_update always updates all the cores with
new pending irq states. If the function returns early it is possible
to get interrupts that has already been acknowledged.
Signed-off-by: Johan Karlsson <johan.karlsson@enea.com>
[PMM: rebased to apply to current master]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Add support to gic_update() for determining the current IRQ
and FIQ status when interrupt grouping is supported. This
simply requires that instead of always raising IRQ we
check the group of the highest priority pending interrupt
and the GICC_CTLR.FIQEn bit to see whether we should raise
IRQ or FIQ.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1430502643-25909-15-git-send-email-peter.maydell@linaro.org
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>
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>
Grouping (GICv2) and Security Extensions change the behaviour of reads
of the highest priority pending interrupt register (ICCHPIR/GICC_HPPIR).
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: 1430502643-25909-12-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-12-git-send-email-greg.bellows@linaro.org
[PMM: make utility fn static; coding style fixes; AckCtl has an effect
for GICv2 without security extensions as well; removed checks on enable
bits because these are done when we set current_pending[cpu]]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
GICs with Security Extensions restrict the non-secure view of the
interrupt priority and priority mask registers.
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: 1430502643-25909-11-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-15-git-send-email-greg.bellows@linaro.org
[PMM: minor code tweaks; fixed missing masking in gic_set_priority_mask
and gic_set_priority]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
For GICs with Security Extensions Non-secure reads have a restricted
view on the current running priority.
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: 1430502643-25909-10-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-11-git-send-email-greg.bellows@linaro.org
[PMM: make function static, minor comment tweak]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
This register is banked in GICs with Security Extensions. Storing the
non-secure copy of BPR in the abpr, which is an alias to the non-secure
copy for secure access. ABPR itself is only accessible from secure state
if the GIC implements Security Extensions.
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: 1430502643-25909-8-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-10-git-send-email-greg.bellows@linaro.org
[PMM: rewrote to fix style issues and correct handling of GICv2
without security extensions]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
The Interrupt Group Registers allow the guest to configure interrupts
into one of two groups, where Group0 are higher priority and may
be routed to IRQ or FIQ, and Group1 are lower priority and always
routed to IRQ. (In a GIC with the security extensions Group0 is
Secure interrupts and Group 1 is NonSecure.)
The GICv2 always supports interrupt grouping; the GICv1 does only
if it implements the security extensions.
This patch implements the ability to read and write the registers;
the actual functionality the bits control will be added in a
subsequent patch.
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: 1430502643-25909-5-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-7-git-send-email-greg.bellows@linaro.org
[PMM: bring GIC_*_GROUP macros into line with the others, ie a
simple SET/CLEAR/TEST rather than GROUP0/GROUP1;
utility gic_has_groups() function;
minor style fixes;
bump vmstate version]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Switch the GIC's MMIO callback functions to the read_with_attrs
and write_with_attrs functions which provide MemTxAttrs. This will
allow the GIC to correctly handle secure and nonsecure register
accesses.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1430502643-25909-4-git-send-email-peter.maydell@linaro.org
Add a QOM property which allows the GIC Security Extensions to be
enabled. These are an optional part of the GICv1 and GICv2 architecture.
This commit just adds the property and some sanity checks that it
is only enabled on GIC revisions that support it.
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: 1430502643-25909-3-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-5-git-send-email-greg.bellows@linaro.org
[PMM: changed property name, added checks that it isn't set for
older GIC revisions or if using the KVM VGIC; reworded commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Create the outbound FIQ lines from the GIC to the CPUs; these are
used if the GIC has security extensions or grouping support.
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: 1430502643-25909-2-git-send-email-peter.maydell@linaro.org
Message-id: 1429113742-8371-2-git-send-email-greg.bellows@linaro.org
[PMM: added FIQ lines to kvm-arm-gic so its interface is the same;
tweaked commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
Take IRQ target mask into account when determining the highest priority
pending interrupt.
Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Message-id: 1407947471-26981-1-git-send-email-serge.fdrv@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Only SGIs must be WI, done by forcing them to their default
(edge-triggered).
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Message-id: 1408372255-12358-4-git-send-email-adam@os.inf.tu-dresden.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Setting the model is only available in pre-v1 GIC models.
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Message-id: 1408372255-12358-3-git-send-email-adam@os.inf.tu-dresden.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The GICD_ICFGR register covers 4 interrupts per byte.
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Message-id: 1408372255-12358-2-git-send-email-adam@os.inf.tu-dresden.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
Commit 40d225009e accidentally changed the behaviour of
gic_acknowledge_irq() for the NVIC. The NVIC doesn't have SGIs,
so this meant we hit an assertion:
gic_acknowledge_irq: Assertion `s->sgi_pending[irq][cpu] != 0' failed.
Return NVIC acknowledge-irq to its previous behaviour, like 11MPCore.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
The GICC_APRn registers are not currently supported by the ARM GIC v2.0
emulation. This patch adds the missing state.
Note that we also change the number of APRs to use a define GIC_NR_APRS
based on the maximum number of preemption levels. This patch also adds
RAZ/WI accessors for the four registers on the emulated CPU interface.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Add a binary_point field to the gic emulation structure and support
setting/getting this register now when we have it. We don't actually
support interrupt grouping yet, oh well.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Right now the arm gic emulation doesn't keep track of the source of an
SGI (which apparently Linux guests don't use, or they're fine with
assuming CPU 0 always).
Add the necessary matrix on the GICState structure and maintain the data
when setting and clearing the pending state of an IRQ and make the state
visible to the guest.
Note that we always choose to present the source as the lowest-numbered
CPU in case multiple cores have signalled the same SGI number to a core
on the system.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The existing implementation of the pending behavior in gic_set_irq,
gic_complete_irq, and the distributor pending set/clear registers does
not follow the semantics of the GICv2.0 specs, but may implement the
11MPCore support. Therefore, maintain the existing semantics for
11MPCore and v7M NVIC and change the behavior to be in accordance with
the GICv2.0 specs for "generic implementations" (s->revision == 1 ||
s->revision == 2).
Generic implementations distinguish between setting a level-triggered
interrupt pending through writes to the GICD_ISPENDR and when hardware
raises the interrupt line. Writing to the GICD_ICPENDR will not cause
the interrupt to become non-pending if the line is still active, and
conversely, if the line is deactivated but the interrupt is marked as
pending through a write to GICD_ISPENDR, the interrupt remains pending.
Handle this situation in the GIC_TEST_PENDING (which now becomes a
static inline named gic_test_pending) and let the 'pending' field
correspond only to the latched state of the D-flip flop in the GICv2.0
specs Figure 4-10.
The following changes are added:
gic_test_pending:
Make this a static inline and split out the 11MPCore from the generic
behavior. For the generic behavior, consider interrupts pending if:
((s->irq_state[irq].pending & (cm) != 0) ||
(!GIC_TEST_EDGE_TRIGGER(irq) && GIC_TEST_LEVEL(irq, cm))
gic_set_irq:
Split out the 11MPCore from the generic behavior. For the generic
behavior, always GIC_SET_LEVEL() on positive level, but only
GIC_SET_PENDING for edge-triggered interrupts and always simply
GIC_CLEAR_LEVEL() on negative level.
gic_complete_irq:
Only resample the line for line-triggered interrupts on an 11MPCore.
Generic implementations will sample the line directly in
gic_test_pending().
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Fix two bugs that would allow changing the state of SGIs through the
ICPENDR and ISPENDRs.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Instead of hardcoding 16 various places in the code, use a define to
make it more clear what is going on.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
* QOM interface fixes and unit test
* Device no_user sanitization and documentation
* Device error reporting improvement
* Conversion of APIC, ICC, IOAPIC to QOM realization model
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Merge remote-tracking branch 'afaerber/tags/qom-devices-for-anthony' into staging
QOM infrastructure fixes and device conversions
* QOM interface fixes and unit test
* Device no_user sanitization and documentation
* Device error reporting improvement
* Conversion of APIC, ICC, IOAPIC to QOM realization model
# gpg: Signature made Tue 24 Dec 2013 09:04:05 AM PST using RSA key ID 3E7E013F
# gpg: Good signature from "Andreas Färber <afaerber@suse.de>"
# gpg: aka "Andreas Färber <afaerber@suse.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 174F 0347 1BCC 221A 6175 6F96 FA2E D12D 3E7E 013F
* afaerber/tags/qom-devices-for-anthony: (24 commits)
qdev-monitor: Improve error message for -device nonexistant
ioapic: QOM'ify ioapic
ioapic: Cleanup for QOM'ification
icc_bus: QOM'ify ICC
apic: QOM'ify APIC
apic: Cleanup for QOM'ification
qdev: Drop misleading qbus_free() function
qom: Detect bad reentrance during object_class_foreach()
tests: Test QOM interface casting
qom: Do not register interface "types" in the type table and fix names
qom: Split out object and class caches
qdev: Document that pointer properties kill device_add
hw: cannot_instantiate_with_device_add_yet due to pointer props
qdev-monitor: Avoid device_add crashing on non-device driver name
qdev: Do not let the user try to device_add when it cannot work
isa: Clean up use of cannot_instantiate_with_device_add_yet
vt82c686: Clean up use of cannot_instantiate_with_device_add_yet
piix3 piix4: Clean up use of cannot_instantiate_with_device_add_yet
ich9: Document why cannot_instantiate_with_device_add_yet
pci-host: Consistently set cannot_instantiate_with_device_add_yet
...
To make the code slightly cleaner to look at and make the save/restore
code easier to understand, introduce this function to set the priority of
interrupts.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Message-id: 1387606179-22709-3-git-send-email-christoffer.dall@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
TRIGGER can really mean mean anything (e.g. was it triggered, is it
level-triggered, is it edge-triggered, etc.). Rename to EDGE_TRIGGER to
make the code comprehensible without looking up the data structure.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Message-id: 1387606179-22709-2-git-send-email-christoffer.dall@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
device_add plugs devices into suitable bus. For "real" buses, that
actually connects the device. For sysbus, the connections need to be
made separately, and device_add can't do that. The device would be
left unconnected, and could not possibly work.
Quite a few, but not all sysbus devices already set
cannot_instantiate_with_device_add_yet in their class init function.
Set it in their abstract base's class init function
sysbus_device_class_init(), and remove the now redundant assignments
from device class init functions.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
In an ideal world, machines can be built by wiring devices together
with configuration, not code. Unfortunately, that's not the world we
live in right now. We still have quite a few devices that need to be
wired up by code. If you try to device_add such a device, it'll fail
in sometimes mysterious ways. If you're lucky, you get an
unmysterious immediate crash.
To protect users from such badness, DeviceClass member no_user used to
make device models unavailable with -device / device_add, but that
regressed in commit 18b6dad. The device model is still omitted from
help, but is available anyway.
Attempts to fix the regression have been rejected with the argument
that the purpose of no_user isn't clear, and it's prone to misuse.
This commit clarifies no_user's purpose. Anthony suggested to rename
it cannot_instantiate_with_device_add_yet_due_to_internal_bugs, which
I shorten somewhat to keep checkpatch happy. While there, make it
bool.
Every use of cannot_instantiate_with_device_add_yet gets a FIXME
comment asking for rationale. The next few commits will clean them
all up, either by providing a rationale, or by getting rid of the use.
With that done, the regression fix is hopefully acceptable.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>