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target/riscv: Add target/riscv/kvm.c to place the public kvm interface

Add target/riscv/kvm.c to place kvm_arch_* function needed by
kvm/kvm-all.c.

Signed-off-by: Yifei Jiang <jiangyifei@huawei.com>
Signed-off-by: Mingwang Li <limingwang@huawei.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Message-id: 20220112081329.1835-3-jiangyifei@huawei.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

update-linux-headers: Add asm-riscv/kvm.h

Add asm-riscv/kvm.h for RISC-V KVM.

Signed-off-by: Yifei Jiang <jiangyifei@huawei.com>
Signed-off-by: Mingwang Li <limingwang@huawei.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Message-id: 20220112081329.1835-2-jiangyifei@huawei.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

hw: timer: ibex_timer: update/add reg address

The following changes:
1. Fixes the incorrectly set CTRL register address. As
per [1] https://docs.opentitan.org/hw/ip/rv_timer/doc/#register-table

The CTRL register is @ 0x04.

This was found when attempting to fixup a bug where a timer_interrupt
was not serviced on TockOS-OpenTitan.

2. Adds ALERT_TEST register as documented on [1], adding repective
switch cases to error handle and later implement functionality.

Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Tested-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Message-id: 20220111071025.4169189-2-alistair.francis@opensource.wdc.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

riscv: opentitan: fixup plic stride len

The following change was made to rectify incorrectly set stride length
on the PLIC [1]. Where it should be 32bit and not 24bit (0x18). This was
discovered whilst attempting to fix a bug where a timer_interrupt was
not serviced on TockOS-OpenTitan.

[1] https://docs.opentitan.org/hw/top_earlgrey/ip_autogen/rv_plic/doc/

Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Tested-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Message-id: 20220111071025.4169189-1-alistair.francis@opensource.wdc.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

hw: timer: ibex_timer: Fixup reading w/o register

This change fixes a bug where a write only register is read.
As per https://docs.opentitan.org/hw/ip/rv_timer/doc/#register-table
the 'INTR_TEST0' register is write only.

Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20220110051606.4031241-1-alistair.francis@opensource.wdc.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target-arm:
* hw/intc/arm_gicv3_its: Fix various minor bugs
* hw/arm/aspeed: Add the i3c device to the AST2600 SoC
* hw/arm: kudo: add lm75s behind bus 1 switch at 75
* hw/arm/virt: Fix support for running guests on hosts
with restricted IPA ranges
* hw/intc/arm_gic: Allow reset of the running priority
* hw/intc/arm_gic: Implement read of GICC_IIDR
* hw/arm/virt: Support for virtio-mem-pci
* hw/arm/virt: Support CPU cluster on ARM virt machine
* docs/can: convert to restructuredText
* hw/net: Move MV88W8618 network device out of hw/arm/ directory
* hw/arm/virt: KVM: Enable PAuth when supported by the host
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Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20220120-1' into staging

target-arm:
* hw/intc/arm_gicv3_its: Fix various minor bugs
* hw/arm/aspeed: Add the i3c device to the AST2600 SoC
* hw/arm: kudo: add lm75s behind bus 1 switch at 75
* hw/arm/virt: Fix support for running guests on hosts
with restricted IPA ranges
* hw/intc/arm_gic: Allow reset of the running priority
* hw/intc/arm_gic: Implement read of GICC_IIDR
* hw/arm/virt: Support for virtio-mem-pci
* hw/arm/virt: Support CPU cluster on ARM virt machine
* docs/can: convert to restructuredText
* hw/net: Move MV88W8618 network device out of hw/arm/ directory
* hw/arm/virt: KVM: Enable PAuth when supported by the host

# gpg: Signature made Thu 20 Jan 2022 16:12:12 GMT
# gpg: using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE
# gpg: issuer "peter.maydell@linaro.org"
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [ultimate]
# gpg: aka "Peter Maydell <pmaydell@gmail.com>" [ultimate]
# gpg: aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [ultimate]
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83 15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20220120-1: (38 commits)
hw/intc/arm_gicv3: Check for !MEMTX_OK instead of MEMTX_ERROR
hw/intc/arm_gicv3_its: Range-check ICID before indexing into collection table
hw/intc/arm_gicv3_its: Check indexes before use, not after
hw/intc/arm_gicv3_its: Factor out "find address of table entry" code
hw/intc/arm_gicv3_its: Fix return codes in process_mapd()
hw/intc/arm_gicv3_its: Fix return codes in process_mapc()
hw/intc/arm_gicv3_its: Fix return codes in process_mapti()
hw/intc/arm_gicv3_its: Refactor process_its_cmd() to reduce nesting
hw/intc/arm_gicv3_its: Fix return codes in process_its_cmd()
hw/intc/arm_gicv3_its: Use enum for return value of process_* functions
hw/intc/arm_gicv3_its: Don't use data if reading command failed
hw/intc/arm_gicv3_its: Fix handling of process_its_cmd() return value
hw/intc/arm_gicv3_its: Convert int ID check to num_intids convention
hw/intc/arm_gicv3_its: Fix event ID bounds checks
hw/arm/aspeed: Add the i3c device to the AST2600 SoC
hw/misc/aspeed_i3c.c: Introduce a dummy AST2600 I3C model.
hw/arm: kudo add lm75s behind bus 1 switch at 75
hw/arm/virt: Drop superfluous checks against highmem
hw/arm/virt: Disable highmem devices that don't fit in the PA range
hw/arm/virt: Use the PA range to compute the memory map
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/intc/arm_gicv3: Check for !MEMTX_OK instead of MEMTX_ERROR

Quoting Peter Maydell:

"These MEMTX_* aren't from the memory transaction
API functions; they're just being used by gicd_readl() and
friends as a way to indicate a success/failure so that the
actual MemoryRegionOps read/write fns like gicv3_dist_read()
can log a guest error."

We are going to introduce more MemTxResult bits, so it is
safer to check for !MEMTX_OK rather than MEMTX_ERROR.

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/intc/arm_gicv3_its: Range-check ICID before indexing into collection table

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

hw/intc/arm_gicv3_its: Check indexes before use, not after

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

hw/intc/arm_gicv3_its: Factor out "find address of table entry" code

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

hw/intc/arm_gicv3_its: Fix return codes in process_mapd()

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

hw/intc/arm_gicv3_its: Fix return codes in process_mapc()

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

hw/intc/arm_gicv3_its: Fix return codes in process_mapti()

Fix process_mapti() 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: 20220111171048.3545974-9-peter.maydell@linaro.org

hw/intc/arm_gicv3_its: Refactor process_its_cmd() to reduce nesting

Refactor process_its_cmd() so that it consistently uses
the structure
do thing;
if (error condition) {
return early;
}
do next thing;

rather than doing some of the work nested inside if (not error)
code blocks.

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: 20220111171048.3545974-8-peter.maydell@linaro.org

hw/intc/arm_gicv3_its: Fix return codes in process_its_cmd()

Fix process_its_cmd() 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: 20220111171048.3545974-7-peter.maydell@linaro.org

hw/intc/arm_gicv3_its: Use enum for return value of process_* functions

When an ITS detects an error in a command, it has an
implementation-defined (CONSTRAINED UNPREDICTABLE) choice of whether
to ignore the command, proceeding to the next one in the queue, or to
stall the ITS command queue, processing nothing further. The
behaviour required when the read of the command packet from memory
fails is less clearly documented, but the same set of choices as for
command errors seem reasonable.

The intention of the QEMU implementation, as documented in the
comments, is that if we encounter a memory error reading the command
packet or one of the various data tables then we should stall, but
for command parameter errors we should ignore the queue and continue.
However, we don't actually do this. To get the desired behaviour,
the various process_* functions need to return true to cause
process_cmdq() to advance to the next command and keep processing,
and false to stall command processing. What they mostly do is return
false for any kind of error.

To make the code clearer, replace the 'bool' return from the process_
functions with an enum which may be either CMD_STALL or CMD_CONTINUE.
In this commit no behaviour changes; in subsequent commits we will
adjust the error-return paths for the process_ functions one by one.

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>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20220111171048.3545974-6-peter.maydell@linaro.org

hw/intc/arm_gicv3_its: Don't use data if reading command failed

In process_cmdq(), we read 64 bits of the command packet, which
contain the command identifier, which we then switch() on to dispatch
to an appropriate sub-function. However, if address_space_ldq_le()
reports a memory transaction failure, we still read the command
identifier out of the data and switch() on it. Restructure the code
so that we stop immediately (stalling the command queue) in this
case.

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: 20220111171048.3545974-5-peter.maydell@linaro.org

hw/intc/arm_gicv3_its: Fix handling of process_its_cmd() return value

process_its_cmd() returns a bool, like all the other process_ functions.
However we were putting its return value into 'res', not 'result',
which meant we would ignore it when deciding whether to continue
or stall the command queue. Fix the typo.

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>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20220111171048.3545974-4-peter.maydell@linaro.org

hw/intc/arm_gicv3_its: Convert int ID check to num_intids convention

The bounds check on the number of interrupt IDs is correct, but
doesn't match our convention; change the variable name, initialize it
to the 2^n value rather than (2^n)-1, and use >= instead of > in the
comparison.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20220111171048.3545974-3-peter.maydell@linaro.org

hw/intc/arm_gicv3_its: Fix event ID bounds checks

In process_its_cmd() and process_mapti() we must check the
event ID against a limit defined by the size field in the DTE,
which specifies the number of ID bits minus one. Convert
this code to our num_foo convention:
* change the variable names
* use uint64_t and 1ULL when calculating the number
of valid event IDs, because DTE.SIZE is 5 bits and
so num_eventids may be up to 2^32
* fix the off-by-one error in the comparison

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20220111171048.3545974-2-peter.maydell@linaro.org

hw/arm/aspeed: Add the i3c device to the AST2600 SoC

Add the new i3c device to the AST2600 SoC.

Signed-off-by: Troy Lee <troy_lee@aspeedtech.com>
Reviewed-by: Graeme Gregory <quic_ggregory@quicinc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Graeme Gregory <quic_ggregory@quicinc.com>
Message-id: 20220111084546.4145785-3-troy_lee@aspeedtech.com
[PMM: tidied commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/misc/aspeed_i3c.c: Introduce a dummy AST2600 I3C model.

Aspeed 2600 SDK enables I3C support by default. The I3C driver will try
to reset the device controller and set it up through device address table
register. This dummy model responds to these registers with default values
as listed in the ast2600v10 datasheet chapter 54.2.

This avoids a guest machine kernel panic due to referencing an
invalid kernel address if the device address table register isn't
set correctly.

Signed-off-by: Troy Lee <troy_lee@aspeedtech.com>
Reviewed-by: Graeme Gregory <quic_ggregory@quicinc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Graeme Gregory <quic_ggregory@quicinc.com>
Message-id: 20220111084546.4145785-2-troy_lee@aspeedtech.com
[PMM: tidied commit message; fixed format strings]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/arm: kudo add lm75s behind bus 1 switch at 75

Reviewed-by: Hao Wu <wuhaotsh@google.com>
Signed-off-by: Patrick Venture <venture@google.com>
Message-id: 20220111172338.1525587-1-venture@google.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/arm/virt: Drop superfluous checks against highmem

Now that the devices present in the extended memory map are checked
against the available PA space and disabled when they don't fit,
there is no need to keep the same checks against highmem, as
highmem really is a shortcut for the PA space being 32bit.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Message-id: 20220114140741.1358263-7-maz@kernel.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/arm/virt: Disable highmem devices that don't fit in the PA range

In order to only keep the highmem devices that actually fit in
the PA range, check their location against the range and update
highest_gpa if they fit. If they don't, mark them as disabled.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20220114140741.1358263-6-maz@kernel.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/arm/virt: Use the PA range to compute the memory map

The highmem attribute is nothing but another way to express the
PA range of a VM. To support HW that has a smaller PA range then
what QEMU assumes, pass this PA range to the virt_set_memmap()
function, allowing it to correctly exclude highmem devices
if they are outside of the PA range.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20220114140741.1358263-5-maz@kernel.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/arm/virt: Honor highmem setting when computing the memory map

Even when the VM is configured with highmem=off, the highest_gpa
field includes devices that are above the 4GiB limit.
Similarily, nothing seem to check that the memory is within
the limit set by the highmem=off option.

This leads to failures in virt_kvm_type() on systems that have
a crippled IPA range, as the reported IPA space is larger than
what it should be.

Instead, honor the user-specified limit to only use the devices
at the lowest end of the spectrum, and fail if we have memory
crossing the 4GiB limit.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Message-id: 20220114140741.1358263-4-maz@kernel.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/arm/virt: Add a control for the the highmem redistributors

Just like we can control the enablement of the highmem PCIe region
using highmem_ecam, let's add a control for the highmem GICv3
redistributor region.

Similarily to highmem_ecam, these redistributors are disabled when
highmem is off.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20220114140741.1358263-3-maz@kernel.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/arm/virt: Add a control for the the highmem PCIe MMIO

Just like we can control the enablement of the highmem PCIe ECAM
region using highmem_ecam, let's add a control for the highmem
PCIe MMIO region.

Similarily to highmem_ecam, this region is disabled when highmem
is off.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20220114140741.1358263-2-maz@kernel.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/intc/arm_gic: Allow reset of the running priority

When running Linux on a machine with GICv2, the kernel can crash while
processing an interrupt and can subsequently start a kdump kernel from
the active interrupt handler. In such a case, the crashed kernel might
not gracefully signal the end of interrupt to the GICv2 hardware. The
kdump kernel will however try to reset the GIC state on startup to get
the controller into a sane state, in particular the kernel writes ones
to GICD_ICACTIVERn and wipes out GICC_APRn to make sure that no
interrupt is active.

The patch adds a logic to recalculate the running priority when
GICC_APRn/GICC_NSAPRn is written which makes sure that the mentioned
reset works with the GICv2 emulation in QEMU too and the kdump kernel
starts receiving interrupts.

The described scenario can be reproduced on an AArch64 QEMU virt machine
with a kdump-enabled Linux system by using the softdog module. The kdump
kernel will hang at some point because QEMU still thinks the running
priority is that of the timer interrupt and asserts no new interrupts to
the system:
$ modprobe softdog soft_margin=10 soft_panic=1
$ cat > /dev/watchdog
[Press Enter to start the watchdog, wait for its timeout and observe
that the kdump kernel hangs on startup.]

Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Message-id: 20220113151916.17978-3-ppavlu@suse.cz
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>