Firing watches on the nodes that still exist is relatively easy; just
walk the tree and look at the nodes with refcount of one.
Firing watches on *deleted* nodes is more fun. We add 'modified_in_tx'
and 'deleted_in_tx' flags to each node. Nodes with those flags cannot
be shared, as they will always be unique to the transaction in which
they were created.
When xs_node_walk would need to *create* a node as scaffolding and it
encounters a deleted_in_tx node, it can resurrect it simply by clearing
its deleted_in_tx flag. If that node originally had any *data*, they're
gone, and the modified_in_tx flag will have been set when it was first
deleted.
We then attempt to send appropriate watches when the transaction is
committed, properly delete the deleted_in_tx nodes, and remove the
modified_in_tx flag from the others.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Given that the whole thing supported copy on write from the beginning,
transactions end up being fairly simple. On starting a transaction, just
take a ref of the existing root; swap it back in on a successful commit.
The main tree has a transaction ID too, and we keep a record of the last
transaction ID given out. if the main tree is ever modified when it isn't
the latest, it gets a new transaction ID.
A commit can only succeed if the main tree hasn't moved on since it was
forked. Strictly speaking, the XenStore protocol allows a transaction to
succeed as long as nothing *it* read or wrote has changed in the interim,
but no implementations do that; *any* change is sufficient to abort a
transaction.
This does not yet fire watches on the changed nodes on a commit. That bit
is more fun and will come in a follow-on commit.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Starts out fairly simple: a hash table of watches based on the path.
Except there can be multiple watches on the same path, so the watch ends
up being a simple linked list, and the head of that list is in the hash
table. Which makes removal a bit of a PITA but it's not so bad; we just
special-case "I had to remove the head of the list and now I have to
replace it in / remove it from the hash table". And if we don't remove
the head, it's a simple linked-list operation.
We do need to fire watches on *deleted* nodes, so instead of just a simple
xs_node_unref() on the topmost victim, we need to recurse down and fire
watches on them all.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
This is a fairly simple implementation of a copy-on-write tree.
The node walk function starts off at the root, with 'inplace == true'.
If it ever encounters a node with a refcount greater than one (including
the root node), then that node is shared with other trees, and cannot
be modified in place, so the inplace flag is cleared and we copy on
write from there on down.
Xenstore write has 'mkdir -p' semantics and will create the intermediate
nodes if they don't already exist, so in that case we flip the inplace
flag back to true as we populate the newly-created nodes.
We put a copy of the absolute path into the buffer in the struct walk_op,
with *two* NUL terminators at the end. As xs_node_walk() goes down the
tree, it replaces the next '/' separator with a NUL so that it can use
the 'child name' in place. The next recursion down then puts the '/'
back and repeats the exercise for the next path element... if it doesn't
hit that *second* NUL termination which indicates the true end of the
path.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
This implements the basic wire protocol for the XenStore commands, punting
all the actual implementation to xs_impl_* functions which all just return
errors for now.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Modified BMC FRU data in yosemite v2 platform.
Tested: Tested and Verified in yosemitev2 platform.
Fixes: 34f73a81e6 ("hw/arm/aspeed: Adding new machine Yosemitev2 in QEMU")
Signed-off-by: Karthikeyan Pasupathi <pkarthikeyan1509@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20230307104833.3587947-1-pkarthikeyan1509@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Added TMP421 type sensor support in tiogapass platform.
Tested: Tested and verified in tiogapass platform.
Signed-off-by: Karthikeyan Pasupathi <pkarthikeyan1509@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20230307103334.3586755-1-pkarthikeyan1509@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Added TMP421 type support in yosemite v2 platform.
Tested: Tested and verified in yosemite V2 platform.
Signed-off-by: Karthikeyan Pasupathi <pkarthikeyan1509@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20230307095239.3583613-1-pkarthikeyan1509@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Commit a4b15a8b introduced a new function blk_pread_nonzeroes(). Instead
of reading directly from the root node of the BlockBackend, it reads
from its 'file' child node. This can happen to mostly work for raw
images (as long as the 'raw' format driver is in use, but not actually
doing anything), but it breaks everything else.
Fix it to read from the root node instead.
Fixes: a4b15a8b9e
Reported-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230307140230.59158-1-kwolf@redhat.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Currently, when a block backend is attached to a m25p80 device and the
associated file size does not match the flash model, QEMU complains
with the error message "failed to read the initial flash content".
This is confusing for the user.
Instead, use helper blk_check_size_and_read_all() introduced by commit
06f1521795 ("pflash: Require backend size to match device, improve
errors").
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Delevoryas <peter@pjd.dev>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20221115151000.2080833-1-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
According to the device DMA logging uAPI, IOVA ranges to be logged by
the device must be provided all at once upon DMA logging start.
As preparation for the following patches which will add device dirty
page tracking, keep a record of all DMA mapped IOVA ranges so later they
can be used for DMA logging start.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-10-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In preparation to be used in device dirty tracking, move the code that
calculate a iova/end range from the container/section. This avoids
duplication on the common checks across listener callbacks.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-9-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The checks are replicated against region_add and region_del
and will be soon added in another memory listener dedicated
for dirty tracking.
Move these into a new helper for avoid duplication.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Avihai Horon <avihaih@nvidia.com>
Link: https://lore.kernel.org/r/20230307125450.62409-8-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In preparation to turn more of the memory listener checks into
common functions, one of the affected places is how we trace when
sections are skipped. Right now there is one for each. Change it
into one single tracepoint `vfio_listener_region_skip` which receives
a name which refers to the callback i.e. region_add and region_del.
Suggested-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-7-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Move the code that finds the container host DMA window against a iova
range. This avoids duplication on the common checks across listener
callbacks.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Avihai Horon <avihaih@nvidia.com>
Link: https://lore.kernel.org/r/20230307125450.62409-6-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There are already two places where dirty page bitmap allocation and
calculations are done in open code.
To avoid code duplication, introduce VFIOBitmap struct and corresponding
alloc function and use them where applicable.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-5-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
If VFIO dirty pages log start/stop/sync fails during migration,
migration should be aborted as pages dirtied by VFIO devices might not
be reported properly.
This is not the case today, where in such scenario only an error is
printed.
Fix it by aborting migration in the above scenario.
Fixes: 758b96b61d ("vfio/migrate: Move switch of dirty tracking into vfio_memory_listener")
Fixes: b6dd6504e3 ("vfio: Add vfio_listener_log_sync to mark dirty pages")
Fixes: 9e7b0442f2 ("vfio: Add ioctl to get dirty pages bitmap during dma unmap")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-4-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There are several places where the %m conversion is used if one of
vfio_dma_map(), vfio_dma_unmap() or vfio_get_dirty_bitmap() fail.
The %m usage in these places is wrong since %m relies on errno value while
the above functions don't report errors via errno.
Fix it by using strerror() with the returned value instead.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-3-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Hardly anybody still uses 32-bit x86 environments for running QEMU with
full system emulation, so let's stop wasting our scarce CI minutes with
this job.
(There are still the 32-bit MinGW and TCI jobs around for having
some compile test coverage on 32-bit)
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Message-Id: <20230306084658.29709-4-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Hardly anybody still uses 32-bit x86 hosts today, so we should start
deprecating them to stop wasting our time and CI minutes here.
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Message-Id: <20230306084658.29709-2-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
nmi.h and notify.h are not needed here, drop them to speed up
the compiling a little bit.
Message-Id: <20230210111438.1114600-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Hexagon's idef-parser machinery uses some bison features that are not
available at older versions. The most preeminent example (as it can
be used as a sentinel) is "%define parse.error verbose". This was
introduced in version 3.0 of the tool, which is able to compile
qemu-hexagon just fine. However, compilation fails with the previous
minor bison release, v2.7. So let's assert the minimum version at
meson.build to give a more comprehensive error message for those trying
to compile QEMU.
[1]: https://www.gnu.org/software/bison/manual/html_node/_0025define-Summary.html#index-_0025define-parse_002eerror
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alessandro Di Federico <ale@rev.ng>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <a6763f9f7b89ea310ab86f9a2b311a05254a1acd.1675779233.git.quic_mathbern@quicinc.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
For long-term distributions that release a new version only very
seldom, we limit the support to five years after the initial release.
Otherwise, we might need to support distros like openSUSE 15 for
up to 7 or even more years in total due to our "two more years
after the next major release" rule, which is just way too much to
handle in a project like QEMU that only has limited human resources.
Message-Id: <20230223193257.1068205-1-thuth@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
* Support for the Zicbiom, ZCicboz, and Zicbop extensions.
* OpenSBI has been updated to version 1.2, see
<https://github.com/riscv-software-src/opensbi/releases/tag/v1.2> for
the release notes.
* Support for setting the virtual address width (ie, sv39/sv48/sv57) on
the command line.
* Support for ACPI on RISC-V.
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Merge tag 'pull-riscv-to-apply-20230306' of https://gitlab.com/palmer-dabbelt/qemu into staging
Sixth RISC-V PR for 8.0
* Support for the Zicbiom, ZCicboz, and Zicbop extensions.
* OpenSBI has been updated to version 1.2, see
<https://github.com/riscv-software-src/opensbi/releases/tag/v1.2> for
the release notes.
* Support for setting the virtual address width (ie, sv39/sv48/sv57) on
the command line.
* Support for ACPI on RISC-V.
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# gpg: Signature made Mon 06 Mar 2023 21:51:36 GMT
# gpg: using RSA key 2B3C3747446843B24A943A7A2E1319F35FBB1889
# gpg: issuer "palmer@dabbelt.com"
# gpg: Good signature from "Palmer Dabbelt <palmer@dabbelt.com>" [unknown]
# gpg: aka "Palmer Dabbelt <palmerdabbelt@google.com>" [unknown]
# 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: 00CE 76D1 8349 60DF CE88 6DF8 EF4C A150 2CCB AB41
# Subkey fingerprint: 2B3C 3747 4468 43B2 4A94 3A7A 2E13 19F3 5FBB 1889
* tag 'pull-riscv-to-apply-20230306' of https://gitlab.com/palmer-dabbelt/qemu: (22 commits)
MAINTAINERS: Add entry for RISC-V ACPI
hw/riscv/virt.c: Initialize the ACPI tables
hw/riscv/virt: virt-acpi-build.c: Add RHCT Table
hw/riscv/virt: virt-acpi-build.c: Add RINTC in MADT
hw/riscv/virt: Enable basic ACPI infrastructure
hw/riscv/virt: Add memmap pointer to RiscVVirtState
hw/riscv/virt: Add a switch to disable ACPI
hw/riscv/virt: Add OEM_ID and OEM_TABLE_ID fields
riscv: Correctly set the device-tree entry 'mmu-type'
riscv: Introduce satp mode hw capabilities
riscv: Allow user to set the satp mode
riscv: Change type of valid_vm_1_10_[32|64] to bool
riscv: Pass Object to register_cpu_props instead of DeviceState
roms/opensbi: Upgrade from v1.1 to v1.2
gitlab/opensbi: Move to docker:stable
hw: intc: Use cpu_by_arch_id to fetch CPU state
target/riscv: cpu: Implement get_arch_id callback
disas/riscv Fix ctzw disassemble
hw/riscv/virt.c: add cbo[mz]-block-size fdt properties
target/riscv: add Zicbop cbo.prefetch{i, r, m} placeholder
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Explain that aio_context_notifier_poll() relies on
aio_notify_accept() to catch all the memory writes that were
done before ctx->notified was set to true.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Ever since commit 8c6b0356b5 ("util/async: make bh_aio_poll() O(1)",
2020-02-22), synchronization between qemu_bh_schedule() and aio_bh_poll()
is happening when the bottom half is enqueued in the bh_list; not
when the flags are set. Update the documentation to match.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
mutex->from_push and mutex->handoff in qemu-coroutine-lock implement
the familiar pattern:
write a write b
smp_mb() smp_mb()
read b read a
The memory barrier is required by the C memory model even after a
SEQ_CST read-modify-write operation such as QSLIST_INSERT_HEAD_ATOMIC.
Add it and avoid the unclear qatomic_mb_read() operation.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The barrier comes after an atomic increment, so it is enough to use
smp_mb__after_rmw(); this avoids a double barrier on x86 systems.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Ensure ordering between clearing the COMPUTING flag and checking
IRQFACT, and between setting the IRQFACT flag and checking
COMPUTING. This ensures that no wakeups are lost.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
QemuEvent is currently broken on ARM due to missing memory barriers
after qatomic_*(). Apart from adding the memory barrier, a closer look
reveals some unpaired memory barriers that are not really needed and
complicated the functions unnecessarily. Also, it is relying on
a memory barrier in ResetEvent(); the barrier _ought_ to be there
but there is really no documentation about it, so make it explicit.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
QemuEvent is currently broken on ARM due to missing memory barriers
after qatomic_*(). Apart from adding the memory barrier, a closer look
reveals some unpaired memory barriers too. Document more clearly what
is going on.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
On ARM, seqcst loads and stores (which QEMU does not use) are compiled
respectively as LDAR and STLR instructions. Even though LDAR is
also used for load-acquire operations, it also waits for all STLRs to
leave the store buffer. Thus, LDAR and STLR alone are load-acquire
and store-release operations, but LDAR also provides store-against-load
ordering as long as the previous store is a STLR.
Compare this to ARMv7, where store-release is DMB+STR and load-acquire
is LDR+DMB, but an additional DMB is needed between store-seqcst and
load-seqcst (e.g. DMB+STR+DMB+LDR+DMB); or with x86, where MOV provides
load-acquire and store-release semantics and the two can be reordered.
Likewise, on ARM sequentially consistent read-modify-write operations only
need to use LDAXR and STLXR respectively for the load and the store, while
on x86 they need to use the stronger LOCK prefix.
In a strange twist of events, however, the _stronger_ semantics
of the ARM instructions can end up causing bugs on ARM, not on x86.
The problems occur when seqcst atomics are mixed with relaxed atomics.
QEMU's atomics try to bridge the Linux API (that most of the developers
are familiar with) and the C11 API, and the two have a substantial
difference:
- in Linux, strongly-ordered atomics such as atomic_add_return() affect
the global ordering of _all_ memory operations, including for example
READ_ONCE()/WRITE_ONCE()
- in C11, sequentially consistent atomics (except for seq-cst fences)
only affect the ordering of sequentially consistent operations.
In particular, since relaxed loads are done with LDR on ARM, they are
not ordered against seqcst stores (which are done with STLR).
QEMU implements high-level synchronization primitives with the idea that
the primitives contain the necessary memory barriers, and the callers can
use relaxed atomics (qatomic_read/qatomic_set) or even regular accesses.
This is very much incompatible with the C11 view that seqcst accesses
are only ordered against other seqcst accesses, and requires using seqcst
fences as in the following example:
qatomic_set(&y, 1); qatomic_set(&x, 1);
smp_mb(); smp_mb();
... qatomic_read(&x) ... ... qatomic_read(&y) ...
When a qatomic_*() read-modify write operation is used instead of one
or both stores, developers that are more familiar with the Linux API may
be tempted to omit the smp_mb(), which will work on x86 but not on ARM.
This nasty difference between Linux and C11 read-modify-write operations
has already caused issues in util/async.c and more are being found.
Provide something similar to Linux smp_mb__before/after_atomic(); this
has the double function of documenting clearly why there is a memory
barrier, and avoiding a double barrier on x86 and s390x systems.
The new macro can already be put to use in qatomic_mb_set().
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
RISC-V ACPI related functionality for virt machine is added in
virt-acpi-build.c. Add the maintainer entry after moving the
ARM ACPI entry under the main ACPI entry.
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230302091212.999767-9-sunilvl@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Initialize the ACPI tables if the acpi option is not
disabled.
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230302091212.999767-8-sunilvl@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISC-V ACPI platforms need to provide RISC-V Hart Capabilities
Table (RHCT). Add this to the ACPI tables.
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230302091212.999767-7-sunilvl@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Add Multiple APIC Description Table (MADT) with the
RINTC structure for each cpu.
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230302091212.999767-6-sunilvl@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Add basic ACPI infrastructure for RISC-V with below tables.
1) DSDT with below basic objects
- CPUs
- fw_cfg
2) FADT revision 6 with HW_REDUCED flag
3) XSDT
4) RSDP
Add this functionality in a new file virt-acpi-build.c and enable
building this infrastructure.
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230302091212.999767-5-sunilvl@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
memmap needs to be exported outside of virt.c so that
modules like acpi can use it. Hence, add a pointer field
in RiscVVirtState structure and initialize it with the
memorymap.
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230302091212.999767-4-sunilvl@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
ACPI will be enabled by default. Add a switch to turn off
for testing and debug purposes.
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230302091212.999767-3-sunilvl@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
ACPI needs OEM_ID and OEM_TABLE_ID for the machine. Add these fields
in the RISCVVirtState structure and initialize with default values.
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230302091212.999767-2-sunilvl@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The 'mmu-type' should reflect what the hardware is capable of so use the
new satp_mode field in RISCVCPUConfig to do that.
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Message-ID: <20230303131252.892893-6-alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Currently, the max satp mode is set with the only constraint that it must be
implemented in QEMU, i.e. set in valid_vm_1_10_[32|64].
But we actually need to add another level of constraint: what the hw is
actually capable of, because currently, a linux booting on a sifive-u54
boots in sv57 mode which is incompatible with the cpu's sv39 max
capability.
So add a new bitmap to RISCVSATPMap which contains this capability and
initialize it in every XXX_cpu_init.
Finally:
- valid_vm_1_10_[32|64] constrains which satp mode the CPU can use
- the CPU hw capabilities constrains what the user may select
- the user's selection then constrains what's available to the guest
OS.
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20230303131252.892893-5-alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISC-V specifies multiple sizes for addressable memory and Linux probes for
the machine's support at startup via the satp CSR register (done in
csr.c:validate_vm).
As per the specification, sv64 must support sv57, which in turn must
support sv48...etc. So we can restrict machine support by simply setting the
"highest" supported mode and the bare mode is always supported.
You can set the satp mode using the new properties "sv32", "sv39", "sv48",
"sv57" and "sv64" as follows:
-cpu rv64,sv57=on # Linux will boot using sv57 scheme
-cpu rv64,sv39=on # Linux will boot using sv39 scheme
-cpu rv64,sv57=off # Linux will boot using sv48 scheme
-cpu rv64 # Linux will boot using sv57 scheme by default
We take the highest level set by the user:
-cpu rv64,sv48=on,sv57=on # Linux will boot using sv57 scheme
We make sure that invalid configurations are rejected:
-cpu rv64,sv39=off,sv48=on # sv39 must be supported if higher modes are
# enabled
We accept "redundant" configurations:
-cpu rv64,sv48=on,sv57=off # Linux will boot using sv48 scheme
And contradictory configurations:
-cpu rv64,sv48=on,sv48=off # Linux will boot using sv39 scheme
Co-Developed-by: Ludovic Henry <ludovic@rivosinc.com>
Signed-off-by: Ludovic Henry <ludovic@rivosinc.com>
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Message-ID: <20230303131252.892893-4-alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
David Woodhouse