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>
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>
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>
Daniel Henrique Barboza <dbarboza@ventanamicro.com> says:
The RISCV_FEATURES_* enum and the CPUArchState::features attribute were
introduced 4+ years ago, as a way to retrieve the enabled hart features
that aren't represented via MISA CSR bits. Time passed on, and
RISCVCPUConfig was introduced. With it, we now have a centralized way of
reading all hart features that are enabled/disabled by the user and the
board. All recent features are reading their correspondent cpu->cfg.X
flag.
All but the 5 features in the RISCV_FEATURE_* enum. These features are
still operating in the same way: set it during riscv_cpu_realize() using
their cpu->cfg value, read it using riscv_feature() when needed. There
is nothing special about them in comparison with all the other features
and extensions to justify this special handling.
This series then is doing two things: first we're actually allowing
users to write the MISA CSR if they so choose. Then we're deprecate each
RISC_FEATURE_* usage until, in patch 11, we remove everything related to
it. All 5 existing RISCV_FEATURE_* features will be handled as everyone
else.
* b4-shazam-merge:
target/riscv/cpu: remove CPUArchState::features and friends
target/riscv: remove RISCV_FEATURE_MMU
hw/riscv/virt.c: do not use RISCV_FEATURE_MMU in create_fdt_socket_cpus()
target/riscv: remove RISCV_FEATURE_PMP
target/riscv: remove RISCV_FEATURE_EPMP
target/riscv/cpu.c: error out if EPMP is enabled without PMP
target/riscv: remove RISCV_FEATURE_DEBUG
target/riscv: allow MISA writes as experimental
target/riscv: do not mask unsupported QEMU extensions in write_misa()
target/riscv: introduce riscv_cpu_cfg()
Message-ID: <20230222185205.355361-1-dbarboza@ventanamicro.com>
[Palmer: use the text from the v1]
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>
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>
The auto completion does not work in some cases.
Case 1.
1. (qemu) info reg
2. Press 'Tab'.
3. It does not auto complete.
Case 2.
1. (qemu) block_resize flo
2. Press 'Tab'.
3. It does not auto complete 'floppy0'.
Since the readline_add_completion_of() may add any completion when
strlen(pfx) is zero, we remove the check with (name[0] == '\0') because
strlen() always returns zero in that case.
Fixes: 52f50b1e9f ("readline: Extract readline_add_completion_of() from monitor")
Cc: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Message-Id: <20230207045241.8843-1-dongli.zhang@oracle.com>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
do_freebsd_sysctlbyname needs to translate the 'name' back down to a OID
so we can intercept the special ones. Do that and call the common wrapper
do_freebsd_sysctl_oid.
Signed-off-by: Kyle Evans <kevans@FreeBSD.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Intercept some syscalls that we need to translate (like the archiecture
we're running on) and translate them. These are only the simplest ones
so far.
Signed-off-by: Juergen Lock <nox@jelal.kn-bremen.de>
Co-Authored-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Stacey Son <sson@FreeBSD.org>
Co-Authored-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Palmer Dabbelt