Bits 10, 6, 2 and 12 of mideleg are read only 1 when the Hypervisor is
enabled. We currently only set them on accesses to mideleg, but they
aren't correctly set on reset. Let's ensure they are always the correct
value.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1617
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240108001328.280222-4-alistair.francis@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
We have been incorrectly adjusting both the interrupt and exception
cause when using the hypervisor extension and trapping to VS-mode. This
patch changes the conditional to ensure we only adjust the cause for
interrupts and not exceptions.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1708
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240108001328.280222-3-alistair.francis@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The CSRs will always be between either CSR_MHPMCOUNTER3 and
CSR_MHPMCOUNTER31 or CSR_MHPMCOUNTER3H and CSR_MHPMCOUNTER31H.
So although ctr_index can't be negative, Coverity doesn't know this and
it isn't obvious to human readers either. Let's add an assert to ensure
that Coverity knows the values will be within range.
To simplify the code let's also change the RV32 adjustment.
Fixes: Coverity CID 1523910
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240108001328.280222-2-alistair.francis@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This patch changes behavior on writing RW=01 to pmpcfg with MML=0.
RWX filed is form of collective WARL with the combination of
pmpcfg.RW=01 remains reserved for future standard use.
According to definition of WARL writing the CSR has no other side
effect. But current implementation change architectural state and
change system behavior. After writing we will get unreadable-unwriteble
region regardless on the previous state.
On the other side WARL said that we should read legal value and nothing
says about what we should write. Current behavior change system state
regardless of whether we read this register or not.
Fixes: ac66f2f0 ("target/riscv: pmp: Ignore writes when RW=01")
Signed-off-by: Ivan Klokov <ivan.klokov@syntacore.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231220153205.11072-1-ivan.klokov@syntacore.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Add support for RVV and Vector CSR KVM regs vstart, vl and vtype.
Support for vregs[] requires KVM side changes and an extra reg (vlenb)
and will be added later.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218204321.75757-5-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Linux RISC-V vector documentation (Document/arch/riscv/vector.rst)
mandates a prctl() in order to allow an userspace thread to use the
Vector extension from the host.
This is something to be done in realize() time, after init(), when we
already decided whether we're using RVV or not. We don't have a
realize() callback for KVM yet, so add kvm_cpu_realize() and enable RVV
for the thread via PR_RISCV_V_SET_CONTROL.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218204321.75757-4-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The emulated AIA within the Linux kernel restores the HART index
of the IMSICs according to the configured AIA settings. During
this process, the group setting is used only when the machine
partitions harts into groups. It's unnecessary to set the group
configuration if the machine has only one socket, as its address
space might not contain the group shift.
Signed-off-by: Yong-Xuan Wang <yongxuan.wang@sifive.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20231218090543.22353-2-yongxuan.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Add a new profile CPU 'rva22s64' to work as an alias of
-cpu rv64i,rva22s64
Like the existing rva22u64 CPU already does with the RVA22U64 profile.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-27-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The RVA22S64 profile consists of the following:
- all mandatory extensions of RVA22U64;
- priv spec v1.12.0;
- satp mode sv39;
- Ssccptr, a cache related named feature that we're assuming always
enable since we don't implement a cache;
- Other named features already implemented: Sstvecd, Sstvala,
Sscounterenw;
- the new Svade named feature that was recently added.
Most of the work is already done, so this patch is enough to implement
the profile.
After this patch, the 'rva22s64' user flag alone can be used with the
rva64i CPU to boot Linux:
-cpu rv64i,rva22s64=true
This is the /proc/cpuinfo with this profile enabled:
# cat /proc/cpuinfo
processor : 0
hart : 0
isa : rv64imafdc_zicbom_zicbop_zicboz_zicntr_zicsr_zifencei_zihintpause_zihpm_zfhmin_zca_zcd_zba_zbb_zbs_zkt_svinval_svpbmt
mmu : sv39
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-26-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Certain S-mode profiles, like RVA22S64 and RVA23S64, mandate all the
mandatory extensions of their respective U-mode profiles. RVA22S64
includes all mandatory extensions of RVA22U64, and the same happens with
RVA23 profiles.
Add a 'parent' field to allow profiles to enable other profiles. This
will allow us to describe S-mode profiles by specifying their parent
U-mode profile, then adding just the S-mode specific extensions.
We're naming the field 'parent' to consider the possibility of other
uses (e.g. a s-mode profile including a previous s-mode profile) in the
future.
Suggested-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-25-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
'satp_mode' is a requirement for supervisor profiles like RVA22S64.
User-mode/application profiles like RVA22U64 doesn't care.
Add 'satp_mode' to the profile description. If a profile requires it,
set it during cpu_set_profile(). We'll also check it during finalize()
to validate if the running config implements the profile.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-24-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Next patch will need to retrieve if a given RISCVCPU is 32 or 64 bit.
The existing helper riscv_is_32bit() (hw/riscv/boot.c) will always check
the first CPU of a given hart array, not any given CPU.
Create a helper to retrieve the info for any given CPU, not the first
CPU of the hart array. The helper is using the same 32 bit check that
riscv_cpu_satp_mode_finalize() was doing.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-23-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Profiles will need to validate satp_mode during their own finalize
methods. This will occur inside riscv_tcg_cpu_finalize_features() for
TCG. Given that satp_mode does not have any pre-req from the accelerator
finalize() method, it's safe to finalize it earlier.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-22-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Some profiles, like RVA22S64, has a priv_spec requirement.
Make this requirement explicit for all profiles. We'll validate this
requirement finalize() time and, in case the user chooses an
incompatible priv_spec while activating a profile, a warning will be
shown.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-21-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
'svade' is a RVA22S64 profile requirement, a profile we're going to add
shortly. It is a named feature (i.e. not a formal extension, not defined
in riscv,isa DT at this moment) defined in [1] as:
"Page-fault exceptions are raised when a page is accessed when A bit is
clear, or written when D bit is clear.".
As far as the spec goes, 'svade' is one of the two distinct modes of
handling PTE_A and PTE_D. The other way, i.e. update PTE_A/PTE_D when
they're cleared, is defined by the 'svadu' extension. Checking
cpu_helper.c, get_physical_address(), we can verify that QEMU is
compliant with that: we will update PTE_A/PTE_D if 'svadu' is enabled,
or throw a page-fault exception if 'svadu' isn't enabled.
So, as far as we're concerned, 'svade' translates to 'svadu must be
disabled'.
We'll implement it like 'zic64b': an internal flag that profiles can
enable. The flag will not be exposed to users.
[1] https://github.com/riscv/riscv-profiles/blob/main/profiles.adoc
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-20-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This CPU was suggested by Alistair [1] and others during the profile
design discussions. It consists of the bare 'rv64i' CPU with rva22u64
enabled by default, like an alias of '-cpu rv64i,rva22u64=true'.
Users now have an even easier way of consuming this user-mode profile by
doing '-cpu rva22u64'. Extensions can be enabled/disabled at will on top
of it.
We can boot Linux with this "user-mode" CPU by doing:
-cpu rva22u64,sv39=true,s=true,zifencei=true
[1] https://lore.kernel.org/qemu-riscv/CAKmqyKP7xzZ9Sx=-Lbx2Ob0qCfB7Z+JO944FQ2TQ+49mqo0q_Q@mail.gmail.com/
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-19-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Expose all profile flags for all CPUs when executing
query-cpu-model-expansion. This will allow callers to quickly determine
if a certain profile is implemented by a given CPU. This includes vendor
CPUs - the fact that they don't have profile user flags doesn't mean
that they don't implement the profile.
After this change it's possible to quickly determine if our stock CPUs
implement the existing rva22u64 profile. Here's a few examples:
$ ./build/qemu-system-riscv64 -S -M virt -display none
-qmp tcp:localhost:1234,server,wait=off
$ ./scripts/qmp/qmp-shell localhost:1234
Welcome to the QMP low-level shell!
Connected to QEMU 8.1.50
- As expected, the 'max' CPU implements the rva22u64 profile.
(QEMU) query-cpu-model-expansion type=full model={"name":"max"}
{"return": {"model":
{"name": "rv64", "props": {... "rva22u64": true, ...}}}}
- rv64 is missing "zba", "zbb", "zbs", "zkt" and "zfhmin":
query-cpu-model-expansion type=full model={"name":"rv64"}
{"return": {"model":
{"name": "rv64", "props": {... "rva22u64": false, ...}}}}
query-cpu-model-expansion type=full model={"name":"rv64",
"props":{"zba":true,"zbb":true,"zbs":true,"zkt":true,"zfhmin":true}}
{"return": {"model":
{"name": "rv64", "props": {... "rva22u64": true, ...}}}}
We have no vendor CPUs that supports rva22u64 (veyron-v1 is the closest
- it is missing just 'zkt').
In short, aside from the 'max' CPU, we have no CPUs that supports
rva22u64 by default.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-18-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Enabling a profile and then disabling some of its mandatory extensions
is a valid use. It can be useful for debugging and testing. But the
common expected use of enabling a profile is to enable all its mandatory
extensions.
Add an user warning when mandatory extensions from an enabled profile
are disabled in the command line. We're also going to disable the
profile flag in this case since the profile must include all the
mandatory extensions. This flag can be exposed by QMP to indicate the
actual profile state after the CPU is realized.
After this patch, this will throw warnings:
-cpu rv64,rva22u64=true,zihintpause=false,zicbom=false,zicboz=false
qemu-system-riscv64: warning: Profile rva22u64 mandates disabled extension zihintpause
qemu-system-riscv64: warning: Profile rva22u64 mandates disabled extension zicbom
qemu-system-riscv64: warning: Profile rva22u64 mandates disabled extension zicboz
Note that the following will NOT throw warnings because the profile is
being enabled last, hence all its mandatory extensions will be enabled:
-cpu rv64,zihintpause=false,zicbom=false,zicboz=false,rva22u64=true
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-17-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
RVG behaves like a profile: a single flag enables a set of bits. Right
now we're considering user choice when handling RVG and zicsr/zifencei
and ignoring user choice on MISA bits.
We'll add user warnings for profiles when the user disables its
mandatory extensions in the next patch. We'll do the same thing with RVG
now to keep consistency between RVG and profile handling.
First and foremost, create a new RVG only helper to avoid clogging
riscv_cpu_validate_set_extensions(). We do not want to annoy users with
RVG warnings like we did in the past (see 9b9741c38f), thus we'll only
warn if RVG was user set and the user disabled a RVG extension in the
command line.
For every RVG MISA bit (IMAFD), zicsr and zifencei, the logic then
becomes:
- if enabled, do nothing;
- if disabled and not user set, enable it;
- if disabled and user set, throw a warning that it's a RVG mandatory
extension.
This same logic will be used for profiles in the next patch.
Note that this is a behavior change, where we would error out if the
user disabled either zicsr or zifencei. As long as users are explicitly
disabling things in the command line we'll let them have a go at it, at
least in this step. We'll error out later in the validation if needed.
Other notable changes from the previous RVG code:
- use riscv_cpu_write_misa_bit() instead of manually updating both
env->misa_ext and env->misa_ext_mask;
- set zicsr and zifencei directly. We're already checking if they
were user set and priv version will never fail for these
extensions, making cpu_cfg_ext_auto_update() redundant.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-16-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Previous patches added several g_hash_table_insert() patterns. Add two
helpers, one for each user hash, to make the code cleaner.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-15-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The profile support is handling multi-letter extensions only. Let's add
support for MISA bits as well.
We'll go through every known MISA bit. If the profile doesn't declare
the bit as mandatory, ignore it. Otherwise, set the bit in env->misa_ext
and env->misa_ext_mask.
Now that we're setting profile MISA bits, one can use the rv64i CPU to boot
Linux using the following options:
-cpu rv64i,rva22u64=true,rv39=true,s=true,zifencei=true
In the near future, when rva22s64 (where, 's', 'zifencei' and sv39 are
mandatory), is implemented, rv64i will be able to boot Linux loading
rva22s64 and no additional flags.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-14-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
We have two instances of the setting/clearing a MISA bit from
env->misa_ext and env->misa_ext_mask pattern. And the next patch will
end up adding one more.
Create a helper to avoid code repetition.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231218125334.37184-13-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
We already track user choice for multi-letter extensions because we
needed to honor user choice when enabling/disabling extensions during
realize(). We refrained from adding the same mechanism for MISA
extensions since we didn't need it.
Profile support requires tne need to check for user choice for MISA
extensions, so let's add the corresponding hash now. It works like the
existing multi-letter hash (multi_ext_user_opts) but tracking MISA bits
options in the cpu_set_misa_ext_cfg() callback.
Note that we can't re-use the same hash from multi-letter extensions
because that hash uses cpu->cfg offsets as keys, while for MISA
extensions we're using MISA bits as keys.
After adding the user hash in cpu_set_misa_ext_cfg(), setting default
values with object_property_set_bool() in add_misa_properties() will end
up marking the user choice hash with them. Set the default value
manually to avoid it.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231218125334.37184-12-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The TCG emulation implements all the extensions described in the
RVA22U64 profile, both mandatory and optional. The mandatory extensions
will be enabled via the profile flag. We'll leave the optional
extensions to be enabled by hand.
Given that this is the first profile we're implementing in TCG we'll
need some ground work first:
- all profiles declared in riscv_profiles[] will be exposed to users.
TCG is the main accelerator we're considering when adding profile
support in QEMU, so for now it's safe to assume that all profiles in
riscv_profiles[] will be relevant to TCG;
- we'll not support user profile settings for vendor CPUs. The flags
will still be exposed but users won't be able to change them;
- profile support, albeit available for all non-vendor CPUs, will be
based on top of the new 'rv64i' CPU. Setting a profile to 'true' means
enable all mandatory extensions of this profile, setting it to 'false'
will disable all mandatory profile extensions of the CPU, which will
obliterate preset defaults. This is not a problem for a bare CPU like
rv64i but it can allow for silly scenarios when using other CPUs. E.g.
an user can do "-cpu rv64,rva22u64=false" and have a bunch of default
rv64 extensions disabled. The recommended way of using profiles is the
rv64i CPU, but users are free to experiment.
For now we'll handle multi-letter extensions only. MISA extensions need
additional steps that we'll take care later. At this point we can boot a
Linux buildroot using rva22u64 using the following options:
-cpu rv64i,rva22u64=true,sv39=true,g=true,c=true,s=true
Note that being an usermode/application profile we still need to
explicitly set 's=true' to enable Supervisor mode to boot Linux.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-11-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
KVM does not have the means to support enabling the rva22u64 profile.
The main reasons are:
- we're missing support for some mandatory rva22u64 extensions in the
KVM module;
- we can't make promises about enabling a profile since it all depends
on host support in the end.
We'll revisit this decision in the future if needed. For now mark the
'rva22u64' profile as unavailable when running a KVM CPU:
$ qemu-system-riscv64 -machine virt,accel=kvm -cpu rv64,rva22u64=true
qemu-system-riscv64: can't apply global rv64-riscv-cpu.rva22u64=true:
'rva22u64' is not available with KVM
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231218125334.37184-10-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The rva22U64 profile, described in:
https://github.com/riscv/riscv-profiles/blob/main/profiles.adoc#rva22-profiles
Contains a set of CPU extensions aimed for 64-bit userspace
applications. Enabling this set to be enabled via a single user flag
makes it convenient to enable a predictable set of features for the CPU,
giving users more predicability when running/testing their workloads.
QEMU implements all possible extensions of this profile. All the so
called 'synthetic extensions' described in the profile that are cache
related are ignored/assumed enabled (Za64rs, Zic64b, Ziccif, Ziccrse,
Ziccamoa, Zicclsm) since we do not implement a cache model.
An abstraction called RISCVCPUProfile is created to store the profile.
'ext_offsets' contains mandatory extensions that QEMU supports. Same
thing with the 'misa_ext' mask. Optional extensions must be enabled
manually in the command line if desired.
The design here is to use the common target/riscv/cpu.c file to store
the profile declaration and export it to the accelerator files. Each
accelerator is then responsible to expose it (or not) to users and how
to enable the extensions.
Next patches will implement the profile for TCG and KVM.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231218125334.37184-9-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Named features (zic64b the sole example at this moment) aren't expose to
users, thus we need another way to expose them.
Go through each named feature, get its boolean value, do the needed
conversions (bool to qbool, qbool to QObject) and add it to output dict.
Another adjustment is needed: named features are evaluated during
finalize(), so riscv_cpu_finalize_features() needs to be mandatory
regardless of whether we have an input dict or not. Otherwise zic64b
will always return 'false', which is incorrect: the default values of
cache blocksizes ([cbom/cbop/cboz]_blocksize) are set to 64, satisfying
the conditions for zic64b.
Here's an API usage example after this patch:
$ ./build/qemu-system-riscv64 -S -M virt -display none
-qmp tcp:localhost:1234,server,wait=off
$ ./scripts/qmp/qmp-shell localhost:1234
Welcome to the QMP low-level shell!
Connected to QEMU 8.1.50
(QEMU) query-cpu-model-expansion type=full model={"name":"rv64"}
{"return": {"model":
{"name": "rv64", "props": {... "zic64b": true, ...}}}}
zic64b is set to 'true', as expected, since all cache sizes are 64
bytes by default.
If we change one of the cache blocksizes, zic64b is returned as 'false':
(QEMU) query-cpu-model-expansion type=full model={"name":"rv64","props":{"cbom_blocksize":128}}
{"return": {"model":
{"name": "rv64", "props": {... "zic64b": false, ...}}}}
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-8-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
zic64b is defined in the RVA22U64 profile [1] as a named feature for
"Cache blocks must be 64 bytes in size, naturally aligned in the address
space". It's a fantasy name for 64 bytes cache blocks. The RVA22U64
profile mandates this feature, meaning that applications using this
profile expects 64 bytes cache blocks.
To make the upcoming RVA22U64 implementation complete, we'll zic64b as
a 'named feature', not a regular extension. This means that:
- it won't be exposed to users;
- it won't be written in riscv,isa.
This will be extended to other named extensions in the future, so we're
creating some common boilerplate for them as well.
zic64b is default to 'true' since we're already using 64 bytes blocks.
If any cache block size (cbo{m,p,z}_blocksize) is changed to something
different than 64, zic64b is set to 'false'.
Our profile implementation will then be able to check the current state
of zic64b and take the appropriate action (e.g. throw a warning).
[1] https://github.com/riscv/riscv-profiles/releases/download/v1.0/profiles.pdf
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-7-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
QEMU already implements zicbom (Cache Block Management Operations) and
zicboz (Cache Block Zero Operations). Commit 59cb29d6a5 ("target/riscv:
add Zicbop cbo.prefetch{i, r, m} placeholder") added placeholders for
what would be the instructions for zicbop (Cache Block Prefetch
Operations), which are now no-ops.
The RVA22U64 profile mandates zicbop, which means that applications that
run with this profile might expect zicbop to be present in the riscv,isa
DT and might behave badly if it's absent.
Adding zicbop as an extension will make our future RVA22U64
implementation more in line with what userspace expects and, if/when
cache block prefetch operations became relevant to QEMU, we already have
the extension flag to turn then on/off as needed.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-6-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
We don't have any form of a 'bare bones' CPU. rv64, our default CPUs,
comes with a lot of defaults. This is fine for most regular uses but
it's not suitable when more control of what is actually loaded in the
CPU is required.
A bare-bones CPU would be annoying to deal with if not by profile
support, a way to load a multitude of extensions with a single flag.
Profile support is going to be implemented shortly, so let's add a CPU
for it.
The new 'rv64i' CPU will have only RVI loaded. It is inspired in the
profile specification that dictates, for RVA22U64 [1]:
"RVA22U64 Mandatory Base
RV64I is the mandatory base ISA for RVA22U64"
And so it seems that RV64I is the mandatory base ISA for all profiles
listed in [1], making it an ideal CPU to use with profile support.
rv64i is a CPU of type TYPE_RISCV_BARE_CPU. It has a mix of features
from pre-existent CPUs:
- it allows extensions to be enabled, like generic CPUs;
- it will not inherit extension defaults, like vendor CPUs.
This is the minimum extension set to boot OpenSBI and buildroot using
rv64i:
./build/qemu-system-riscv64 -nographic -M virt \
-cpu rv64i,sv39=true,g=true,c=true,s=true,u=true
Our minimal riscv,isa in this case will be:
# cat /proc/device-tree/cpus/cpu@0/riscv,isa
rv64imafdc_zicntr_zicsr_zifencei_zihpm_zca_zcd#
[1] https://github.com/riscv/riscv-profiles/blob/main/profiles.adoc
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-5-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
We'll add a new bare CPU type that won't have any default priv_ver. This
means that the CPU will default to priv_ver = 0, i.e. 1.10.0.
At the same we'll allow these CPUs to enable extensions at will, but
then, if the extension has a priv_ver newer than 1.10, we'll end up
disabling it. Users will then need to manually set priv_ver to something
other than 1.10 to enable the extensions they want, which is not ideal.
Change the setter() of extensions to allow user enabled extensions to
bump the priv_ver of the CPU. This will make it convenient for users to
enable extensions for CPUs that doesn't set a default priv_ver.
This change does not affect any existing CPU: vendor CPUs does not allow
extensions to be enabled, and generic CPUs are already set to priv_ver
LATEST.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-4-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Our current logic in get/setters of MISA and multi-letter extensions
works because we have only 2 CPU types, generic and vendor, and by using
"!generic" we're implying that we're talking about vendor CPUs. When adding
a third CPU type this logic will break so let's handle it beforehand.
In set_misa_ext_cfg() and set_multi_ext_cfg(), check for "vendor" cpu instead
of "not generic". The "generic CPU" checks remaining are from
riscv_cpu_add_misa_properties() and cpu_add_multi_ext_prop() before
applying default values for the extensions.
This leaves us with:
- vendor CPUs will not allow extension enablement, all other CPUs will;
- generic CPUs will inherit default values for extensions, all others
won't.
And now we can add a new, third CPU type, that will allow extensions to
be enabled and will not inherit defaults, without changing the existing
logic.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-3-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
We want to add a new CPU type for bare CPUs that will inherit specific
traits of the 2 existing types:
- it will allow for extensions to be enabled/disabled, like generic
CPUs;
- it will NOT inherit defaults, like vendor CPUs.
We can make this conditions met by adding an explicit type for the
existing vendor CPUs and change the existing logic to not imply that
"not generic" means vendor CPUs.
Let's add the "vendor" CPU type first.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231218125334.37184-2-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Add support for amocas.w/d/q instructions which are part of the ratified
Zacas extension: https://github.com/riscv/riscv-zacas
Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20231207153842.32401-2-rbradford@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
kvm_riscv_reg_id() returns an id encoded with an ulong size, i.e. an u32
size when running TARGET_RISCV32 and u64 when running TARGET_RISCV64.
Rename it to kvm_riscv_reg_id_ulong() to enhance code readability. It'll
be in line with the existing kvm_riscv_reg_id_<size>() helpers.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231208183835.2411523-6-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Create a RISCV_CONFIG_REG() macro, similar to what other regs use, to
hide away some of the boilerplate.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231208183835.2411523-5-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
KVM_REG_RISCV_TIMER regs are always u64 according to the KVM API, but at
this moment we'll return u32 regs if we're running a RISCV32 target.
Use the kvm_riscv_reg_id_u64() helper in RISCV_TIMER_REG() to fix it.
Reported-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231208183835.2411523-4-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
KVM_REG_RISCV_FP_D regs are always u64 size. Using kvm_riscv_reg_id() in
RISCV_FP_D_REG() ends up encoding the wrong size if we're running with
TARGET_RISCV32.
Create a new helper that returns a KVM ID with u64 size and use it with
RISCV_FP_D_REG().
Reported-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231208183835.2411523-3-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
KVM_REG_RISCV_FP_F regs have u32 size according to the API, but by using
kvm_riscv_reg_id() in RISCV_FP_F_REG() we're returning u64 sizes when
running with TARGET_RISCV64. The most likely reason why no one noticed
this is because we're not implementing kvm_cpu_synchronize_state() in
RISC-V yet.
Create a new helper that returns a KVM ID with u32 size and use it in
RISCV_FP_F_REG().
Reported-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20231208183835.2411523-2-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
mvendorid is an uint32 property, mimpid/marchid are uint64 properties.
But their getters are returning bools. The reason this went under the
radar for this long is because we have no code using the getters.
The problem can be seem via the 'qom-get' API though. Launching QEMU
with the 'veyron-v1' CPU, a model with:
VEYRON_V1_MVENDORID: 0x61f (1567)
VEYRON_V1_MIMPID: 0x111 (273)
VEYRON_V1_MARCHID: 0x8000000000010000 (9223372036854841344)
This is what the API returns when retrieving these properties:
(qemu) qom-get /machine/soc0/harts[0] mvendorid
true
(qemu) qom-get /machine/soc0/harts[0] mimpid
true
(qemu) qom-get /machine/soc0/harts[0] marchid
true
After this patch:
(qemu) qom-get /machine/soc0/harts[0] mvendorid
1567
(qemu) qom-get /machine/soc0/harts[0] mimpid
273
(qemu) qom-get /machine/soc0/harts[0] marchid
9223372036854841344
Fixes: 1e34150045 ("target/riscv/cpu.c: restrict 'mvendorid' value")
Fixes: a1863ad368 ("target/riscv/cpu.c: restrict 'mimpid' value")
Fixes: d6a427e2c0 ("target/riscv/cpu.c: restrict 'marchid' value")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231211170732.2541368-1-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The Sv32 page-based virtual-memory scheme described in RISCV privileged
spec Section 5.3 supports 34-bit physical addresses for RV32, so the
PMP scheme must support addresses wider than XLEN for RV32. However,
PMP address register format is still 32 bit wide.
Signed-off-by: Ivan Klokov <ivan.klokov@syntacore.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231123091214.20312-1-ivan.klokov@syntacore.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
If CPU does not implement the Vector extension, it usually means
mstatus vs hardwire to zero. So we should not allow write a
non-zero value to this field.
Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231215023313.1708-1-zhiwei_liu@linux.alibaba.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
According to the specification, the th.dcache.cvall1 can be executed
under all priviledges.
The specification about xtheadcmo located in,
https://github.com/T-head-Semi/thead-extension-spec/blob/master/xtheadcmo/dcache_cval1.adoc
Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Christoph Muellner <christoph.muellner@vrull.eu>
Message-ID: <20231208094315.177-1-zhiwei_liu@linux.alibaba.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The RISC-V v spec 16.6 section says that the whole vector register move
instructions operate as if EEW=SEW. So it should depends on the vsew
field of vtype register.
Signed-off-by: Max Chou <max.chou@sifive.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20231129170400.21251-3-max.chou@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The ratified version of RISC-V V spec section 16.6 says that
`The instructions operate as if EEW=SEW`.
So the whole vector register move instructions depend on the vtype
register that means the whole vector register move instructions should
raise an illegal-instruction exception when vtype.vill=1.
Signed-off-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20231129170400.21251-2-max.chou@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The name "iothread" is overloaded. Use the term Big QEMU Lock (BQL)
instead, it is already widely used and unambiguous.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20240102153529.486531-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The mcycle/minstret counter's stop flag is mistakenly updated on a copy
on stack. Thus the counter increments even when the CY/IR bit in the
mcountinhibit register is set. This commit corrects its behavior.
Fixes: 3780e33732 (target/riscv: Support mcycle/minstret write operation)
Signed-off-by: Xu Lu <luxu.kernel@bytedance.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Use generic cpu_model_from_type() when the CPU model name needs to
be extracted from the CPU type name.
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20231114235628.534334-23-gshan@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
For all targets, the CPU class returned from CPUClass::class_by_name()
and object_class_dynamic_cast(oc, CPU_RESOLVING_TYPE) need to be
compatible. Lets apply the check in cpu_class_by_name() for once,
instead of having the check in CPUClass::class_by_name() for individual
target.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Gavin Shan <gshan@redhat.com>
Message-ID: <20231114235628.534334-4-gshan@redhat.com>
