mcycle/minstret are actually WARL registers and can be written with any
given value. With SBI PMU extension, it will be used to store a initial
value provided from supervisor OS. The Qemu also need prohibit the counter
increment if mcountinhibit is set.
Support mcycle/minstret through generic counter infrastructure.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-Id: <20220620231603.2547260-8-atishp@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The RISC-V privilege specification provides flexibility to implement
any number of counters from 29 programmable counters. However, the QEMU
implements all the counters.
Make it configurable through pmu config parameter which now will indicate
how many programmable counters should be implemented by the cpu.
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-Id: <20220620231603.2547260-5-atishp@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The PMU counters are supported via cpu config "Counters" which doesn't
indicate the correct purpose of those counters.
Rename the config property to pmu to indicate that these counters
are performance monitoring counters. This aligns with cpu options for
ARM architecture as well.
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-Id: <20220620231603.2547260-4-atishp@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
According to v-spec, tail agnostic behavior can be either kept as
undisturbed or set elements' bits to all 1s. To distinguish the
difference of tail policies, QEMU should be able to simulate the tail
agnostic behavior as "set tail elements' bits to all 1s".
There are multiple possibility for agnostic elements according to
v-spec. The main intent of this patch-set tries to add option that
can distinguish between tail policies. Setting agnostic elements to
all 1s allows QEMU to express this.
This is the first commit regarding the optional tail agnostic
behavior. Follow-up commits will add this optional behavior
for all rvv instructions.
Signed-off-by: eop Chen <eop.chen@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <165449614532.19704.7000832880482980398-5@git.sr.ht>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Whether or not VSEIP is pending isn't reflected in env->mip and must
instead be determined from hstatus.vgein and hgeip. As a result a
CPU in WFI won't wake on a VSEIP, which violates the WFI behavior as
specified in the privileged ISA. Just use riscv_cpu_all_pending()
instead, which already accounts for VSEIP.
Signed-off-by: Andrew Bresticker <abrestic@rivosinc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20220531210544.181322-1-abrestic@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Currently, the [m|s]tval CSRs are set with trapping instruction encoding
only for illegal instruction traps taken at the time of instruction
decoding.
In RISC-V world, a valid instructions might also trap as illegal or
virtual instruction based to trapping bits in various CSRs (such as
mstatus.TVM or hstatus.VTVM).
We improve setting of [m|s]tval CSRs for all types of illegal and
virtual instruction traps.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20220511144528.393530-4-apatel@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Because some operating systems don't correctly parse long ISA extension
string, this commit adds short-isa-string boolean option to disable
generating long ISA extension strings on Device Tree.
For instance, enabling Zfinx and Zdinx extensions and booting Linux (5.17 or
earlier) with FPU support caused a kernel panic.
Operating Systems which short-isa-string might be helpful:
1. Linux (5.17 or earlier)
2. FreeBSD (at least 14.0-CURRENT)
3. OpenBSD (at least current development version)
Signed-off-by: Tsukasa OI <research_trasio@irq.a4lg.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <7c1fe5f06b0a7646a47e9bcdddb1042bb60c69c8.1652181972.git.research_trasio@irq.a4lg.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
RISC-V privilege spec defines that mtime is exposed as a memory-mapped
machine-mode read-write register. However, as QEMU uses host monotonic
timer as timer source, this makes mtime to be read-only in RISC-V
ACLINT.
This patch makes mtime to be writable by recording the time delta value
between the mtime value to be written and the timer value at the time
mtime is written. Time delta value is then added back whenever the timer
value is retrieved.
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20220420080901.14655-4-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The RISC-V specification states that:
"Supervisor-level external interrupts are made pending based on the
logical-OR of the software-writable SEIP bit and the signal from the
external interrupt controller."
We currently only allow either the interrupt controller or software to
set the bit, which is incorrect.
This patch removes the miclaim mask when writing MIP to allow M-mode
software to inject interrupts, even with an interrupt controller.
We then also need to keep track of which source is setting MIP_SEIP. The
final value is a OR of both, so we add two bools and use that to keep
track of the current state. This way either source can change without
losing the correct value.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/904
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220317061817.3856850-3-alistair.francis@opensource.wdc.com>
To allow/disallow the CSR access based on the privilege spec, a new field
in the csr_ops is introduced. It also adds the privileged specification
version (v1.12) for the CSRs introduced in the v1.12. This includes the
new ratified extensions such as Vector, Hypervisor and secconfig CSR.
However, it doesn't enforce the privilege version in this commit.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-Id: <20220303185440.512391-4-atishp@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
ArchCPU is our interface with target-specific code. Use it as
a forward-declared opaque pointer (abstract type), having its
structure defined by each target.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220214183144.27402-15-f4bug@amsat.org>
While CPUState is our interface with generic code, CPUArchState is
our interface with target-specific code. Use CPUArchState as an
abstract type, defined by each target.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220214183144.27402-13-f4bug@amsat.org>
The AIA spec defines programmable 8-bit priority for each local interrupt
at M-level, S-level and VS-level so we extend local interrupt processing
to consider AIA interrupt priorities. The AIA CSRs which help software
configure local interrupt priorities will be added by subsequent patches.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20220204174700.534953-10-anup@brainfault.org
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The machine or device emulation should be able to force set certain
CPU features because:
1) We can have certain CPU features which are in-general optional
but implemented by RISC-V CPUs on the machine.
2) We can have devices which require a certain CPU feature. For example,
AIA IMSIC devices expect AIA CSRs implemented by RISC-V CPUs.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Message-id: 20220204174700.534953-6-anup@brainfault.org
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Current xlen has been used in helper functions and many other places.
The computation of current xlen is not so trivial, so that we should
recompute it as little as possible.
Fortunately, xlen only changes in very seldom cases, such as exception,
misa write, mstatus write, cpu reset, migration load. So that we can only
recompute xlen in this places and cache it into CPURISCVState.
Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20220120122050.41546-6-zhiwei_liu@c-sky.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>