The spec can be found in https://github.com/riscv/riscv-zicond.
Two instructions are added:
- czero.eqz: Moves zero to a register rd, if the condition rs2 is
equal to zero, otherwise moves rs1 to rd.
- czero.nez: Moves zero to a register rd, if the condition rs2 is
nonzero, otherwise moves rs1 to rd.
Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Message-ID: <20230221091009.36545-1-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The XTheadMemPair does not define any restrictions for store-pair
instructions (th.sdd or th.swd). However, the current code enforces
the restrictions that are required for load-pair instructions.
Let's fix this by removing this code.
Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20230220095612.1529031-1-christoph.muellner@vrull.eu>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This bug has a noticeable behavior of falling back to the main loop and
respawning a redundant translation block including a single instruction
when the end address of the compressive instruction is exactly on a page
boundary, and slows down running system performance.
Signed-off-by: Shaobo Song <songshaobo@eswincomputing.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20230220072732.568-1-songshaobo@eswincomputing.com>
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>
Move sstc()/sstc32() to where all predicate() routines live, and
smstateen_acc_ok() to near {read,write}_xenvcfg().
Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Message-ID: <20230228104035.1879882-19-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 seed CSR is not reported in the CSR XML hence gdb cannot
access it.
Fix it by adding a debugger check in its predicate() routine.
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: <20230228104035.1879882-15-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
At present user timer and counter CSRs are not reported in the
CSR XML hence gdb cannot access them.
Fix it by adding a debugger check in their predicate() routine.
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: <20230228104035.1879882-14-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
It's worth noting that the vector CSR predicate() has a similar
run-time check logic to the FPU CSR. With the previous patch our
gdbstub can correctly report these vector CSRs via the CSR xml.
Commit 719d3561b2 ("target/riscv: gdb: support vector registers for rv64 & rv32")
inserted these vector CSRs in an ad-hoc, non-standard way in the
riscv-vector.xml. Now we can treat these CSRs no different from
other CSRs.
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: <20230228104035.1879882-13-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Since commit 94452ac4cf ("target/riscv: remove fflags, frm, and fcsr from riscv-*-fpu.xml")
the 3 FPU CSRs are removed from the XML target decription. The
original intent of that commit was based on the assumption that
the 3 FPU CSRs will show up in the riscv-csr.xml so the ones in
riscv-*-fpu.xml are redundant. But unforuantely that is not true.
As the FPU CSR predicate() has a run-time check on MSTATUS.FS,
at the time when CSR XML is generated MSTATUS.FS is unset, hence
no FPU CSRs will be reported.
The FPU CSR predicate() already considered such a case of being
accessed by a debugger. All we need to do is to turn on debugger
mode before calling predicate().
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: <20230228104035.1879882-12-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>
Use env_archcpu() to get RISCVCPU pointer from env directly.
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: <20230228104035.1879882-10-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Use the register index that has already been calculated in the
pmpcfg_csr_{read,write} call.
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: <20230228104035.1879882-9-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The read_only variable is currently declared as an 'int', but it
should really be a 'bool'.
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: <20230228104035.1879882-8-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
There is no need to generate the CSR XML if the Zicsr extension
is not enabled.
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: <20230228104035.1879882-6-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Use a variable 'base_reg' to represent cs->gdb_num_regs so that
the call to ricsv_gen_dynamic_vector_xml() can be placed in one
single line for better readability.
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: <20230228104035.1879882-5-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
At present riscv_csrrw_check() checks the CSR predicate() against
NULL and throws RISCV_EXCP_ILLEGAL_INST if it is NULL. But this is
a pure software check, and has nothing to do with the emulation of
the hardware behavior, thus it is inappropriate to return illegal
instruction exception when software forgets to install the hook.
Change to use g_assert() instead.
Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Weiwei Li<liweiwei@iscas.ac.cn>
Message-ID: <20230228104035.1879882-4-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The priority policy of riscv_csrrw_check() was once adjusted in
commit eacaf44019 ("target/riscv: Fix priority of csr related check in riscv_csrrw_check")
whose commit message says the CSR existence check should come before
the access control check, but the code changes did not agree with
the commit message, that the predicate() check actually came after
the read / write check.
In fact this was intentional. Add some comments there so that people
won't bother trying to change it without a solid reason.
Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Weiwei Li<liweiwei@iscas.ac.cn>
Message-ID: <20230228104035.1879882-3-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The gdbstub CSR XML is dynamically generated according to the result
of the CSR predicate() result. This has been working fine until
commit 7100fe6c24 ("target/riscv: Enable privileged spec version 1.12")
introduced the privilege spec version check in riscv_csrrw_check().
When debugging the 'sifive_u' machine whose priv spec is at 1.10,
gdbstub reports priv spec 1.12 CSRs like menvcfg in the XML, hence
we see "remote failure reply 'E14'" message when examining all CSRs
via "info register system" from gdb.
Add the priv spec version check in the CSR XML generation logic to
fix this issue.
Fixes: 7100fe6c24 ("target/riscv: Enable privileged spec version 1.12")
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: <20230228104035.1879882-2-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISC-V defines a handful of extensions related to floating point, along
with various relationships between these and other extensions. This
patch set adds support for the Zvfh, Zvhfmin, and Zve64d extensions;
along with a handful of fixes and cleanups related to the other
floating-point extension relationships.
* b4-shazam-merge
target/riscv: Expose properties for Zv* extensions
target/riscv: Simplify check for EEW = 64 in trans_rvv.c.inc
target/riscv: Fix check for vector load/store instructions when EEW=64
target/riscv: Add support for Zvfh/zvfhmin extensions
target/riscv: Remove rebundunt check for zve32f and zve64f
target/riscv: Replace check for F/D to Zve32f/Zve64d in trans_rvv.c.inc
target/riscv: Simplify check for Zve32f and Zve64f
target/riscv: Indent fixes in cpu.c
target/riscv: Add propertie check for Zvfh{min} extensions
target/riscv: Fix relationship between V, Zve*, F and D
target/riscv: Add cfg properties for Zv* extensions
target/riscv: Simplify the check for Zfhmin and Zhinxmin
target/riscv: Fix the relationship between Zhinxmin and Zhinx
target/riscv: Fix the relationship between Zfhmin and Zfh
Message-ID: <20230215020539.4788-1-liweiwei@iscas.ac.cn>
[Palmer: commit text]
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Only V extension supports EEW = 64 in these cases: Zve64* extensions don't
support EEW = 64 in these cases as commented before the check.
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: <20230215020539.4788-14-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The V extension supports all vector load and store instructions except
the V extension does not support EEW=64 for index values when XLEN=32.
(Section 18.3)
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: <20230215020539.4788-13-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Zvfh supports vector float point instructions with SEW = 16
and supports conversions between 8-bit integers and binary16 values.
Zvfhmin supports vfwcvt.f.f.v and vfncvt.f.f.w instructions.
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: <20230215020539.4788-12-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Require_zve32/64f have been overlapped by require_rvf/require_scale_rvf.
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: <20230215020539.4788-11-liweiwei@iscas.ac.cn>
[Palmer: commit text]
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Check for Zve32f/Zve64d can overlap check for F/D.
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: <20230215020539.4788-10-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
V/Zve64f depend on Zve32f, so we can only check Zve32f in these cases.
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: <20230215020539.4788-9-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
We needn't check Zfh and Zhinx in these instructions.
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: <20230215020539.4788-4-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Just like zfh and zfhmin, Zhinxmin is part of Zhinx so Zhinxmin
will be enabled when Zhinx is enabled.
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: <20230215020539.4788-3-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Zfhmin is part of Zfh, so Zfhmin will be enabled when Zfh is enabled.
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: <20230215020539.4788-2-liweiwei@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The attribute is no longer used since we can retrieve all the enabled
features in the hart by using cpu->cfg instead.
Remove env->feature, riscv_feature() and riscv_set_feature(). We also
need to bump vmstate_riscv_cpu version_id and minimal_version_id since
'features' is no longer being migrated.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20230222185205.355361-11-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISCV_FEATURE_MMU is set whether cpu->cfg.mmu is set, so let's just use
the flag directly instead.
With this change the enum is also removed. It is worth noticing that
this enum, and all the RISCV_FEATURES_* that were contained in it,
predates the existence of the cpu->cfg object. Today, using cpu->cfg is
an easier way to retrieve all the features and extensions enabled in the
hart.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20230222185205.355361-10-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISCV_FEATURE_PMP is being set via riscv_set_feature() by mirroring the
cpu->cfg.pmp flag. Use the flag instead.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20230222185205.355361-8-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISCV_FEATURE_EPMP is always set to the same value as the cpu->cfg.epmp
flag. Use the flag directly.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20230222185205.355361-7-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Instead of silently ignoring the EPMP setting if there is no PMP
available, error out informing the user that EPMP depends on PMP
support:
$ ./qemu-system-riscv64 -cpu rv64,pmp=false,x-epmp=true
qemu-system-riscv64: Invalid configuration: EPMP requires PMP support
This will force users to pick saner options in the QEMU command line.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20230222185205.355361-6-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISCV_FEATURE_DEBUG will always follow the value defined by
cpu->cfg.debug flag. Read the flag instead.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20230222185205.355361-5-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
At this moment, and apparently since ever, we have no way of enabling
RISCV_FEATURE_MISA. This means that all the code from write_misa(), all
the nuts and bolts that handles how to properly write this CSR, has
always been a no-op as well because write_misa() will always exit
earlier.
This seems to be benign in the majority of cases. Booting an Ubuntu
'virt' guest and logging all the calls to 'write_misa' shows that no
writes to MISA CSR was attempted. Writing MISA, i.e. enabling/disabling
RISC-V extensions after the machine is powered on, seems to be a niche
use.
After discussions in the mailing list, most notably in [1], we reached
the consensus that this code is not suited to be exposed to users
because it's not well tested, but at the same time removing it is a bit
extreme because we would like to fix it, and it's easier to do so with
the code available to use instead of fetching it from git log.
The approach taken here is to get rid of RISCV_FEATURE_MISA altogether
and use a new experimental flag called x-misa-w. The default value is
false, meaning that we're keeping the existing behavior of doing nothing
if a write_misa() is attempted. As with any existing experimental flag,
x-misa-w is also a temporary flag that we need to remove once we fix
write_misa().
[1] https://lists.gnu.org/archive/html/qemu-devel/2023-02/msg05092.html
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-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: <20230222185205.355361-4-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The masking done using env->misa_ext_mask already filters any extension
that QEMU doesn't support. If the hart supports the extension then QEMU
supports it as well.
If the masking done by env->misa_ext_mask is somehow letting unsupported
QEMU extensions pass by, misa_ext_mask itself needs to be fixed instead.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230222185205.355361-3-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
We're going to do changes that requires accessing the RISCVCPUConfig
struct from the RISCVCPU, having access only to a CPURISCVState 'env'
pointer. Add a helper to make the code easier to read.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20230222185205.355361-2-dbarboza@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20221217172907.8364-7-philmd@linaro.org>
The 'hwaddr' type is only available / meaningful on system emulation.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221216215519.5522-6-philmd@linaro.org>
The 'hwaddr' type is only available / meaningful on system emulation.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221216215519.5522-5-philmd@linaro.org>
vslide1up_##BITWIDTH is used by the vslide1up.vx and vslide1up.vf. So its
scalar input should be uint64_t to hold the 64 bits float register.And the
same for vslide1down_##BITWIDTH.
This bug is caught when run these instructions on qemu-riscv32.
Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Message-ID: <20230213094550.29621-1-zhiwei_liu@linux.alibaba.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
