This function is the core of the RISC-V validations for TCG CPUs, and it
has a lot going on.
Functions in cpu.c were made public to allow them to be used by the KVM
accelerator class later on. 'cpu_cfg_ext_get_min_version()' is notably
hard to move it to another file due to its dependency with isa_edata_arr[]
array, thus make it public and use it as is for now.
riscv_cpu_validate_set_extensions() is kept public because it's used by
csr.c in write_misa().
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20230925175709.35696-4-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
As per ISA:
"For CSRRWI, if rd=x0, then the instruction shall not read the CSR and
shall not cause any of the side effects that might occur on a CSR read."
trans_csrrwi() and trans_csrrw() call do_csrw() if rd=x0, do_csrw() calls
riscv_csrrw_do64(), via helper_csrw() passing NULL as *ret_value.
Signed-off-by: Nikita Shubin <n.shubin@yadro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20230808090914.17634-1-nikita.shubin@maquefel.me>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
These are WARL fields - zero out the bits for unavailable counters and
special case the TM bit in mcountinhibit which is hardwired to zero.
This patch achieves this by modifying the value written so that any use
of the field will see the correctly masked bits.
Tested by modifying OpenSBI to write max value to these CSRs and upon
subsequent read the appropriate number of bits for number of PMUs is
enabled and the TM bit is zero in mcountinhibit.
Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20230802124906.24197-1-rbradford@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Pointer mask is also affected by MPRV which means cur_pmbase/pmmask
should also take MPRV into consideration. As pointer mask for instruction
is not supported currently, so we can directly update cur_pmbase/pmmask
based on address related mode and xlen affected by MPRV now.
Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-Id: <20230614032547.35895-3-liweiwei@iscas.ac.cn>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
write_misa() must use as much common logic as possible. We want to open
code just the bits that are exclusive to the CSR write operation and TCG
internals.
Our validation is done with riscv_cpu_validate_set_extensions(), but we
need a small tweak first. When enabling RVG we're doing:
env->misa_ext |= RVI | RVM | RVA | RVF | RVD;
env->misa_ext_mask = env->misa_ext;
This works fine for realize() time but this can potentially overwrite
env->misa_ext_mask if we reutilize the function for write_misa().
Instead of doing misa_ext_mask = misa_ext, sum up the RVG extensions in
misa_ext_mask as well. This won't change realize() time behavior
(misa_ext_mask will be == misa_ext) and will ensure that write_misa()
won't change misa_ext_mask by accident.
After that, rewrite write_misa() to work as follows:
- mask the write using misa_ext_mask to avoid enabling unsupported
extensions;
- suppress RVC if the next insn isn't aligned;
- disable RVG if any of RVG dependencies are being disabled by the user;
- assign env->misa_ext and run riscv_cpu_validate_set_extensions(). On
error, rollback env->misa_ext to its original value, logging a
GUEST_ERROR to inform the user about the failed write;
- handle RVF and MSTATUS_FS and continue as usual.
Let's keep write_misa() as experimental for now until this logic gains
enough mileage.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-Id: <20230517135714.211809-12-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
- Trap satp/hgatp accesses from HS-mode when MSTATUS.TVM is enabled.
- Trap satp accesses from VS-mode when HSTATUS.VTVM is enabled.
- Raise RISCV_EXCP_ILLEGAL_INST when U-mode executes SFENCE.VMA/SINVAL.VMA.
- Raise RISCV_EXCP_VIRT_INSTRUCTION_FAULT when VU-mode executes
SFENCE.VMA/SINVAL.VMA or VS-mode executes SFENCE.VMA/SINVAL.VMA with
HSTATUS.VTVM enabled.
- Raise RISCV_EXCP_VIRT_INSTRUCTION_FAULT when VU-mode executes
HFENCE.GVMA/HFENCE.VVMA/HINVAL.GVMA/HINVAL.VVMA.
Signed-off-by: Yi Chen <chenyi2000@zju.edu.cn>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230406101559.39632-1-chenyi2000@zju.edu.cn>
Signed-off-by: Alistair Francis <alistair.francis@wdc.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>
Daniel Henrique Barboza <dbarboza@ventanamicro.com> says:
These cleanups were suggested by LIU Zhiwei during the review of
d3e6d5762b ("Merge patch series "make write_misa a no-op and FEATURE_*
cleanups"").
* b4-shazam-merge:
target/riscv/csr.c: avoid env_archcpu() usages when reading RISCVCPUConfig
target/riscv/csr.c: use riscv_cpu_cfg() to avoid env_cpu() pointers
target/riscv/csr.c: simplify mctr()
target/riscv/csr.c: use env_archcpu() in ctr()
Message-ID: <20230224174520.92490-1-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Weiwei Li <liweiwei@iscas.ac.cn> says:
This patchset adds support svadu extension. It also fixes some
relationship between *envcfg fields and Svpbmt/Sstc extensions.
Specification for Svadu extension can be found in:
https://github.com/riscv/riscv-svadu
* b4-shazam-merge:
target/riscv: Export Svadu property
target/riscv: Add *envcfg.HADE related check in address translation
target/riscv: Add *envcfg.PBMTE related check in address translation
target/riscv: Add csr support for svadu
target/riscv: Fix the relationship of PBMTE/STCE fields between menvcfg and henvcfg
target/riscv: Fix the relationship between menvcfg.PBMTE/STCE and Svpbmt/Sstc extensions
Message-ID: <20230224040852.37109-1-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Bin Meng <bmeng@tinylab.org> says:
At present gdbstub reports an incorrect / incomplete CSR list in the
target description XML, for example:
- menvcfg is reported in 'sifive_u' machine
- fcsr is missing in a F/D enabled processor
The issue is caused by:
- priv spec version check is missing when reporting CSRs
- CSR predicate() routine is called without turning on the debugger flag
* b4-shazam-merge:
target/riscv: Group all predicate() routines together
target/riscv: Drop priv level check in mseccfg predicate()
target/riscv: Allow debugger to access sstc CSRs
target/riscv: Allow debugger to access {h, s}stateen CSRs
target/riscv: Allow debugger to access seed CSR
target/riscv: Allow debugger to access user timer and counter CSRs
target/riscv: gdbstub: Drop the vector CSRs in riscv-vector.xml
target/riscv: gdbstub: Turn on debugger mode before calling CSR predicate()
target/riscv: Avoid reporting odd-numbered pmpcfgX in the CSR XML for RV64
target/riscv: Simplify getting RISCVCPU pointer from env
target/riscv: Simplify {read, write}_pmpcfg() a little bit
target/riscv: Use 'bool' type for read_only
target/riscv: Coding style fixes in csr.c
target/riscv: gdbstub: Do not generate CSR XML if Zicsr is disabled
target/riscv: gdbstub: Minor change for better readability
target/riscv: Use g_assert() for the predicate() NULL check
target/riscv: Add some comments to clarify the priority policy of riscv_csrrw_check()
target/riscv: gdbstub: Check priv spec version before reporting CSR
Message-ID: <20230228104035.1879882-1-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
riscv_csrrw_check() already does the generic privilege level check
hence there is no need to do the specific M-mode access check in
the mseccfg predicate().
With this change debugger can access the mseccfg CSR anytime.
Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Message-ID: <20230228104035.1879882-18-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
At present with a debugger attached sstc CSRs can only be accssed
when CPU is in M-mode, or configured correctly.
Fix it by adjusting their predicate() routine logic so that the
static config check comes before the run-time check, as well as
adding a debugger check.
Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Message-ID: <20230228104035.1879882-17-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
At present {h,s}stateen CSRs are not reported in the CSR XML
hence gdb cannot access them.
Fix it by adjusting their predicate() routine logic so that the
static config check comes before the run-time check, as well as
adding a debugger check.
Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Message-ID: <20230228104035.1879882-16-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
At present the odd-numbered PMP configuration registers for RV64 are
reported in the CSR XML by QEMU gdbstub. However these registers do
not exist on RV64 so trying to access them from gdb results in 'E14'.
Move the pmpcfgX index check from the actual read/write routine to
the PMP CSR predicate() routine, so that non-existent pmpcfgX won't
be reported in the CSR XML for RV64.
Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20230228104035.1879882-11-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
