Update the various GIC ID and feature registers for GICv4:
* PIDR2 [7:4] is the GIC architecture revision
* GICD_TYPER.DVIS is 1 to indicate direct vLPI injection support
* GICR_TYPER.VLPIS is 1 to indicate redistributor support for vLPIs
* GITS_TYPER.VIRTUAL is 1 to indicate vLPI support
* GITS_TYPER.VMOVP is 1 to indicate that our VMOVP implementation
handles cross-ITS synchronization for the guest
* ICH_VTR_EL2.nV4 is 0 to indicate direct vLPI injection support
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-38-peter.maydell@linaro.org
The VINVALL command should cause any cached information in the
ITS or redistributor for the specified vCPU to be dropped or
otherwise made consistent with the in-memory LPI configuration
tables.
Here we implement the command and table parsing, leaving the
redistributor part as a stub for the moment, as usual.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-22-peter.maydell@linaro.org
Implement the GICv4 VMOVI command, which moves the pending state
of a virtual interrupt from one redistributor to another. As with
MOVI, we handle the "parse and validate command arguments and
table lookups" part in the ITS source file, and pass the final
results to a function in the redistributor which will do the
actual operation. As with the "make a VLPI pending" change,
for the moment we leave that redistributor function as a stub,
to be implemented in a later commit.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-21-peter.maydell@linaro.org
Implement the ITS side of the handling of the INV command for
virtual interrupts; as usual this calls into a redistributor
function which we leave as a stub to fill in later.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-20-peter.maydell@linaro.org
We were previously implementing INV (like INVALL) to just blow away
cached highest-priority-pending-LPI information on all connected
redistributors. For GICv4.0, this isn't going to be sufficient,
because the LPI we are invalidating cached information for might be
either physical or virtual, and the required action is different for
those two cases. So we need to do the full process of looking up the
ITE from the devid and eventid. This also means we can do the error
checks that the spec lists for this command.
Split out INV handling into a process_inv() function like our other
command-processing functions. For the moment, stick to handling only
physical LPIs; we will add the vLPI parts later.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-19-peter.maydell@linaro.org
The VSYNC command forces the ITS to synchronize all outstanding ITS
operations for the specified vPEID, so that subsequent writes to
GITS_TRANSLATER honour them. The QEMU implementation is always in
sync, so for us this is a nop, like the existing SYNC command.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-18-peter.maydell@linaro.org
Implement the GICv4 VMOVP command, which updates an entry in the vPE
table to change its rdbase field. This command is unique in the ITS
command set because its effects must be propagated to all the other
ITSes connected to the same GIC as the ITS which executes the VMOVP
command.
The GICv4 spec allows two implementation choices for handling the
propagation to other ITSes:
* If GITS_TYPER.VMOVP is 1, the guest only needs to issue the command
on one ITS, and the implementation handles the propagation to
all ITSes
* If GITS_TYPER.VMOVP is 0, the guest must issue the command on
every ITS, and arrange for the ITSes to synchronize the updates
with each other by setting ITSList and Sequence Number fields
in the command packets
We choose the GITS_TYPER.VMOVP = 1 approach, and synchronously
execute the update on every ITS.
For GICv4.1 this command has extra fields in the command packet and
additional behaviour. We define the 4.1-only fields with the FIELD
macro, but only implement the GICv4.0 version of the command.
Note that we don't update the reported GITS_TYPER value here;
we'll do that later in a commit which updates all the reported
feature bit and ID register values for GICv4.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-17-peter.maydell@linaro.org
[PMM: Moved gicv3_foreach_its() to arm_gicv3_its_common.h,
for consistency with gicv3_add_its()]
The GICv4 ITS VMOVP command's semantics require it to perform the
operation on every ITS connected to the same GIC that the ITS that
received the command is attached to. This means that the GIC object
needs to keep a pointer to every ITS that is connected to it
(previously it was sufficient for the ITS to have a pointer to its
GIC).
Add a glib ptrarray to the GICv3 object which holds pointers to every
connected ITS, and make the ITS add itself to the array for the GIC
it is connected to when it is realized.
Note that currently all QEMU machine types with an ITS have exactly
one ITS in the system, so typically the length of this ptrarray will
be 1. Multiple ITSes are typically used to improve performance on
real hardware, so we wouldn't need to have more than one unless we
were modelling a real machine type that had multile ITSes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[PMM: Moved gicv3_add_its() to arm_gicv3_its_common.h to avoid
compilation error building the KVM ITS]
Message-id: 20220408141550.1271295-16-peter.maydell@linaro.org
For GICv4, interrupt table entries read by process_its_cmd() may
indicate virtual LPIs which are to be directly injected into a VM.
Implement the ITS side of the code for handling this. This is
similar to the existing handling of physical LPIs, but instead of
looking up a collection ID in a collection table, we look up a vPEID
in a vPE table. As with the physical LPIs, we leave the rest of the
work to code in the redistributor device.
The redistributor half will be implemented in a later commit;
for now we just provide a stub function which does nothing.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-15-peter.maydell@linaro.org
Split the part of process_its_cmd() which is specific to physical
interrupts into its own function. This is the part which starts by
taking the ICID and looking it up in the collection table. The
handling of virtual interrupts is significantly different (involving
a lookup in the vPE table) so structuring the code with one
sub-function for the physical interrupt case and one for the virtual
interrupt case will be clearer than putting both cases in one large
function.
The code for handling the "remove mapping from ITE" for the DISCARD
command remains in process_its_cmd() because it is common to both
virtual and physical interrupts.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-14-peter.maydell@linaro.org
Factor out the sequence of looking up a CTE from an ICID including
the validity and error checks.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-13-peter.maydell@linaro.org
The operation of finding an interrupt table entry given a (DeviceID,
EventID) pair is necessary in multiple different ITS commands. The
process requires first using the DeviceID as an index into the device
table to find the DTE, and then useng the EventID as an index into
the interrupt table specified by that DTE to find the ITE. We also
need to handle all the possible error cases: indexes out of range,
table memory not readable, table entries not valid.
Factor this out into a separate lookup_ite() function which we
can then call from the places where we were previously open-coding
this sequence. We'll also need this for some of the new GICv4.0
commands.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-12-peter.maydell@linaro.org
In the ItsCmdResult enum, we currently distinguish only CMD_STALL
(failure, stall processing of the command queue) and CMD_CONTINUE
(keep processing the queue), and we use the latter both for "there
was a parameter error, go on to the next command" and "the command
succeeded, go on to the next command". Sometimes we would like to
distinguish those two cases, so add CMD_CONTINUE_OK to the enum to
represent the success situation, and use it in the relevant places.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-11-peter.maydell@linaro.org
Implement the GICv4 VMAPP command, which writes an entry to the vPE
table.
For GICv4.1 this command has extra fields in the command packet
and additional behaviour. We define the 4.1-only fields with the
FIELD macro, but only implement the GICv4.0 version of the command.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-10-peter.maydell@linaro.org
Implement the GICv4 VMAPI and VMAPTI commands. These write
an interrupt translation table entry that maps (DeviceID,EventID)
to (vPEID,vINTID,doorbell). The only difference between VMAPI
and VMAPTI is that VMAPI assumes vINTID == EventID rather than
both being specified in the command packet.
(This code won't be reachable until we allow the GIC version to be
set to 4. Support for reading this new virtual-interrupt DTE and
handling it correctly will be implemented in a later commit.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-9-peter.maydell@linaro.org
The GICv4 defines a new in-guest-memory table for the ITS: this is
the vPE table. Implement the new GITS_BASER2 register which the
guest uses to tell the ITS where the vPE table is located, including
the decode of the register fields into the TableDesc structure which
we do for the GITS_BASER<n> when the guest enables the ITS.
We guard provision of the new register with the its_feature_virtual()
function, which does a check of the GITS_TYPER.Virtual bit which
indicates presence of ITS support for virtual LPIs. Since this bit
is currently always zero, GICv4-specific features will not be
accessible to the guest yet.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-8-peter.maydell@linaro.org
In process_mapti() we check interrupt IDs to see whether they are
in the valid LPI range. Factor this out into its own utility
function, as we're going to want it elsewhere too for GICv4.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-7-peter.maydell@linaro.org
We use the common function gicv3_idreg() to supply the CoreSight ID
register values for the GICv3 for the copies of these ID registers in
the distributor, redistributor and ITS register frames. This isn't
quite correct, because while most of the register values are the
same, the PIDR0 value should vary to indicate which of these three
frames it is. (You can see this and also the correct values of these
PIDR0 registers by looking at the GIC-600 or GIC-700 TRMs, for
example.)
Make gicv3_idreg() take an extra argument for the PIDR0 value.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-5-peter.maydell@linaro.org
In commit b6f96009ac we split do_process_its_cmd() from
process_its_cmd(), but forgot the usual blank line between function
definitions. Add it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-2-peter.maydell@linaro.org
In commit 84d43d2e82 we rearranged the logging of errors in
process_mapc(), and inadvertently dropped the trailing newlines
from the log messages. Restore them. The same commit also
attempted to switch the ICID printing to hex (which is how we
print ICIDs elsewhere) but only did half the job, adding the
0x prefix but leaving the format string at %d; correct to %x.
Fixes: 84d43d2e82 ("hw/intc/arm_gicv3_its: In MAPC with V=0, don't check rdbase field")
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>
We forgot a space in some log messages, so the output ended
up looking like
gicv3_dist_write: invalid guest write at offset 0000000000008000size 8
with a missing space before "size". Add the missing spaces.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220303202341.2232284-5-peter.maydell@linaro.org
For debugging guest use of the ITS, it can be helpful to trace
when the ITS reads and writes the in-memory tables.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220303202341.2232284-3-peter.maydell@linaro.org
When debugging code that's using the ITS, it's helpful to
see tracing of the ITS commands that the guest executes. Add
suitable trace events.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220303202341.2232284-2-peter.maydell@linaro.org
In most of the ITS command processing, we check different error
possibilities one at a time and log them appropriately. In
process_mapti() and process_mapd() we have code which checks
multiple error cases at once, which means the logging is less
specific than it could be. Split those cases up.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-14-peter.maydell@linaro.org
When handling MAPI/MAPTI, we allow the supplied interrupt ID to be
either 1023 or something in the valid LPI range. This is a mistake:
only a real valid LPI is allowed. (The general behaviour of the ITS
is that most interrupt ID fields require a value in the LPI range;
the exception is that fields specifying a doorbell value, which are
all in GICv4 commands, allow also 1023 to mean "no doorbell".)
Remove the condition that incorrectly allows 1023 here.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-13-peter.maydell@linaro.org
In the MAPC command, if V=0 this is a request to delete a collection
table entry and the rdbase field of the command packet will not be
used. In particular, the specification says that the "UNPREDICTABLE
if rdbase is not valid" only applies for V=1.
We were doing a check-and-log-guest-error on rdbase regardless of
whether the V bit was set, and also (harmlessly but confusingly)
storing the contents of the rdbase field into the updated collection
table entry. Update the code so that if V=0 we don't check or use
the rdbase field value.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-12-peter.maydell@linaro.org
Currently we track in the TableDesc and CmdQDesc structs the state of
the GITS_BASER<n> and GITS_CBASER Valid bits. However we aren't very
consistent abut checking the valid field: we test it in update_cte()
and update_dte(), but not anywhere else we look things up in tables.
The GIC specification says that it is UNPREDICTABLE if a guest fails
to set any of these Valid bits before enabling the ITS via
GITS_CTLR.Enabled. So we can choose to handle Valid == 0 as
equivalent to a zero-length table. This is in fact how we're already
catching this case in most of the table-access paths: when Valid is 0
we leave the num_entries fields in TableDesc or CmdQDesc set to zero,
and then the out-of-bounds check "index >= num_entries" that we have
to do anyway before doing any of these table lookups will always be
true, catching the no-valid-table case without any extra code.
So we can remove the checks on the valid field from update_cte()
and update_dte(): since these happen after the bounds check there
was never any case when the test could fail. That means the valid
fields would be entirely unused, so just remove them.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-11-peter.maydell@linaro.org
Make the update_ite() struct use the new ITEntry struct, so that
callers don't need to assemble the in-memory ITE data themselves, and
only get_ite() and update_ite() need to care about that in-memory
layout. We can then drop the no-longer-used IteEntry struct
definition.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-10-peter.maydell@linaro.org
In get_ite() we currently return the caller some of the fields of an
Interrupt Table Entry via a set of pointer arguments, and validate
some of them internally (interrupt type and valid bit) to return a
simple true/false 'valid' indication. Define a new ITEntry struct
which has all the fields that the in-memory ITE has, and bring the
get_ite() function in to line with get_dte() and get_cte().
This paves the way for handling virtual interrupts, which will want
a different subset of the fields in the ITE. Handling them under
the old "lots of pointer arguments" scheme would have meant a
confusingly large set of arguments for this function.
The new struct ITEntry is obviously confusably similar to the
existing IteEntry struct, whose fields are the raw 12 bytes
of the in-memory ITE. In the next commit we will make update_ite()
use ITEntry instead of IteEntry, which will allow us to delete
the IteEntry struct and remove the confusion.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-9-peter.maydell@linaro.org
The get_ite() code has some awkward nested if statements; clean
them up by returning early if the memory accesses fail.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-8-peter.maydell@linaro.org
In get_ite() and update_ite() we work with a 12-byte in-guest-memory
table entry, which we intend to handle as an 8-byte value followed by
a 4-byte value. Unfortunately the calculation of the address of the
4-byte value is wrong, because we write it as:
table_base_address + (index * entrysize) + 4
(obfuscated by the way the expression has been written)
when it should be + 8. This bug meant that we overwrote the top
bytes of the 8-byte value with the 4-byte value. There are no
guest-visible effects because the top half of the 8-byte value
contains only the doorbell interrupt field, which is used only in
GICv4, and the two bugs in the "write ITE" and "read ITE" codepaths
cancel each other out.
We can't simply change the calculation, because this would break
migration of a (TCG) guest from the old version of QEMU which had
in-guest-memory interrupt tables written using the buggy version of
update_ite(). We must also at the same time change the layout of the
fields within the ITE_L and ITE_H values so that the in-memory
locations of the fields we care about (VALID, INTTYPE, INTID and
ICID) stay the same.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-7-peter.maydell@linaro.org
Make update_cte() take a CTEntry struct rather than all the fields
of the new CTE as separate arguments.
This brings it into line with the update_dte() API.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-6-peter.maydell@linaro.org
In the ITS, a CTE is an entry in the collection table, which contains
multiple fields. Currently the function get_cte() which reads one
entry from the device table returns a success/failure boolean and
passes back the raw 64-bit integer CTE value via a pointer argument.
We then extract fields from the CTE as we need them.
Create a real C struct with the same fields as the CTE, and
populate it in get_cte(), so that that function and update_cte()
are the only ones which need to care about the in-guest-memory
format of the CTE.
This brings get_cte()'s API into line with get_dte().
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-5-peter.maydell@linaro.org
Make update_dte() take a DTEntry struct rather than all the fields of
the new DTE as separate arguments.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-4-peter.maydell@linaro.org
In the ITS, a DTE is an entry in the device table, which contains
multiple fields. Currently the function get_dte() which reads one
entry from the device table returns it as a raw 64-bit integer,
which we then pass around in that form, only extracting fields
from it as we need them.
Create a real C struct with the same fields as the DTE, and
populate it in get_dte(), so that that function and update_dte()
are the only ones that need to care about the in-guest-memory
format of the DTE.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-3-peter.maydell@linaro.org
Currently the ITS accesses each 8-byte doubleword in a 4-doubleword
command packet with a separate address_space_ldq_le() call. This is
awkward because the individual command processing functions have
ended up with code to handle "load more doublewords out of the
packet", which is both unwieldy and also a potential source of bugs
because it's not obvious when looking at a line that pulls a field
out of the 'value' variable which of the 4 doublewords that variable
currently holds.
Switch to using address_space_map() to map the whole command packet
at once and fish the four doublewords out of it. Then each process_*
function can start with a few lines of code that extract the fields
it cares about.
This requires us to split out the guts of process_its_cmd() into a
new do_process_its_cmd(), because we were previously overloading the
value and offset arguments as a backdoor way to directly pass the
devid and eventid from a write to GITS_TRANSLATER. The new
do_process_its_cmd() takes those arguments directly, and
process_its_cmd() is just a wrapper that does the "read fields from
command packet" part.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-2-peter.maydell@linaro.org
Implement the ITS MOVI command. This command specifies a (physical) LPI
by DeviceID and EventID and provides a new ICID for it. The ITS must
find the interrupt translation table entry for the LPI, which will
tell it the old ICID. It then moves the pending state of the LPI from
the old redistributor to the new one and updates the ICID field in
the translation table entry.
This is another GICv3 ITS command that we forgot to implement. Linux
does use this one, but only if the guest powers off one of its CPUs.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220122182444.724087-15-peter.maydell@linaro.org
Implement the ITS MOVALL command, which takes all the pending
interrupts on a source redistributor and makes the not-pending on
that source redistributor and pending on a destination redistributor.
This is a GICv3 ITS command which we forgot to implement. (It is
not used by Linux guests.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220122182444.724087-14-peter.maydell@linaro.org
Currently when we fill in a TableDesc based on the value the guest
has written to the GITS_BASER<n> register, we calculate both:
* num_entries : the number of entries in the table, constrained
by the amount of memory the guest has given it
* num_ids : the number of IDs we support for this table,
constrained by the implementation choices and the architecture
(eg DeviceIDs are 16 bits, so num_ids is 1 << 16)
When validating ITS commands, however, we check only num_ids,
thus allowing a broken guest to specify table entries that
index off the end of it. This will only corrupt guest memory,
but the ITS is supposed to reject such commands as invalid.
Instead of calculating both num_entries and num_ids, set
num_entries to the minimum of the two limits, and check that.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220122182444.724087-13-peter.maydell@linaro.org
The ITS has a bank of 8 GITS_BASER<n> registers, which allow the
guest to specify the base address of various data tables. Each
register has a read-only type field indicating which table it is for
and a read-write field where the guest can write in the base address
(among other things). We currently allow the guest to write the
writeable fields for all eight registers, even if the type field is 0
indicating "Unimplemented". This means the guest can provoke QEMU
into asserting by writing an address into one of these unimplemented
base registers, which bypasses the "if (!value) continue" check in
extract_table_params() and lets us hit the assertion that the type
field is one of the permitted table types.
Prevent the assertion by not allowing the guest to write to the
unimplemented base registers. This means their value will remain 0
and extract_table_params() will ignore them.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220122182444.724087-12-peter.maydell@linaro.org
The MemoryRegionOps gicv3_its_translation_ops currently provides only
a .write_with_attrs function, because the only register in this
region is the write-only GITS_TRANSLATER. However, if you don't
provide a read function and the guest tries reading from this memory
region, QEMU will crash because
memory_region_read_with_attrs_accessor() calls a NULL pointer.
Add a read function which always returns 0, to cover both bogus
attempts to read GITS_TRANSLATER and also reads from the rest of the
region, which is documented to be reserved, RES0.
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: 20220122182444.724087-11-peter.maydell@linaro.org
The ITS specification says that when the guest writes to GITS_CBASER
this causes GITS_CREADR to be cleared. However it does not have an
equivalent clause for GITS_CWRITER. (This is because GITS_CREADR is
read-only, but GITS_CWRITER is writable and the guest can initialize
it.) Remove the code that clears GITS_CWRITER on GITS_CBASER writes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220122182444.724087-6-peter.maydell@linaro.org
The current ITS code clears GITS_CREADR when GITS_CTLR.ENABLED is set.
This is not correct -- guest code can validly clear ENABLED and then
set it again and expect the ITS to continue processing where it left
off. Remove the erroneous assignment.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220122182444.724087-5-peter.maydell@linaro.org
In our implementation, all ITSes connected to a GIC share a single
AddressSpace, which we keep in the GICv3State::dma_as field and
initialized based on the GIC's 'sysmem' property. The right place
to set it up by calling address_space_init() is therefore in the
GIC's realize method, not the ITS's realize.
This fixes a theoretical bug where QEMU hangs on startup if the board
model creates two ITSes connected to the same GIC -- we would call
address_space_init() twice on the same AddressSpace*, which creates
an infinite loop in the QTAILQ that softmmu/memory.c uses to store
its list of AddressSpaces and causes any subsequent attempt to
iterate through that list to loop forever. There aren't any board
models like that in the tree at the moment, though.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220122182444.724087-4-peter.maydell@linaro.org
The ITS currently has no tracepoints; add a minimal set
that allows basic monitoring of guest register accesses and
reading of commands from the command queue.
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: 20220122182444.724087-3-peter.maydell@linaro.org
In process_its_cmd(), we read an ICID out of the interrupt table
entry, and then use it as an index into the collection table. Add a
check that it is within range for the collection table first.
This check is not strictly necessary, because:
* we range check the ICID from the guest before writing it into
the interrupt table entry, so the the only way to get an
out of range ICID in process_its_cmd() is if a badly-behaved
guest is writing directly to the interrupt table memory
* the collection table is in guest memory, so QEMU won't fall
over if we read off the end of it
However, it seems clearer to include the check.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20220111171048.3545974-14-peter.maydell@linaro.org
In a few places in the ITS command handling functions, we were
doing the range-check of an event ID or device ID only after using
it as a table index; move the checks to before the uses.
This misordering wouldn't have very bad effects because the
tables are in guest memory anyway.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20220111171048.3545974-13-peter.maydell@linaro.org
The ITS has several tables which all share a similar format,
described by the TableDesc struct: the guest may configure them
to be a single-level table or a two-level table. Currently we
open-code the process of finding the table entry in all the
functions which read or write the device table or the collection
table. Factor out the "get the address of the table entry"
logic into a new function, so that the code which needs to
read or write a table entry only needs to call table_entry_addr()
and then perform a suitable load or store to that address.
Note that the error handling is slightly complicated because
we want to handle two cases differently:
* failure to read the L1 table entry should end up causing
a command stall, like other kinds of DMA error
* an L1 table entry that says there is no L2 table for this
index (ie whose valid bit is 0) must result in us treating
the table entry as not-valid on read, and discarding
writes (this is mandated by the spec)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20220111171048.3545974-12-peter.maydell@linaro.org
Fix process_mapd() to consistently return CMD_STALL for memory
errors and CMD_CONTINUE for parameter errors, as we claim in the
comments that we do.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220111171048.3545974-11-peter.maydell@linaro.org
Fix process_mapc() to consistently return CMD_STALL for memory
errors and CMD_CONTINUE for parameter errors, as we claim in the
comments that we do.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220111171048.3545974-10-peter.maydell@linaro.org
Peter Maydell