Commit Graph

1661 Commits

Author SHA1 Message Date
Peter Maydell
4f7b1ecba8 target: Set TCGCPUOps::cpu_exec_halt to target's has_work implementation
Currently the TCGCPUOps::cpu_exec_halt method is optional, and if it
is not set then the default is to call the CPUClass::has_work
method (which has an identical function signature).

We would like to make the cpu_exec_halt method mandatory so we can
remove the runtime check and fallback handling.  In preparation for
that, make all the targets which don't need special handling in their
cpu_exec_halt set it to their cpu_has_work implementation instead of
leaving it unset.  (This is every target except for arm and i386.)

In the riscv case this requires us to make the function not
be local to the source file it's defined in.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2024-07-11 11:41:34 +01:00
Alvin Chang
2f5a2315b8 target/riscv: Apply modularized matching conditions for icount trigger
We have implemented trigger_common_match(), which checks if the enabled
privilege levels of the trigger match CPU's current privilege level. We
can invoke trigger_common_match() to check the privilege levels of the
type 3 triggers.

Signed-off-by: Alvin Chang <alvinga@andestech.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240626132247.2761286-4-alvinga@andestech.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-27 13:09:16 +10:00
Alvin Chang
72dec1666f target/riscv: Apply modularized matching conditions for watchpoint
We have implemented trigger_common_match(), which checks if the enabled
privilege levels of the trigger match CPU's current privilege level.
Remove the related code in riscv_cpu_debug_check_watchpoint() and invoke
trigger_common_match() to check the privilege levels of the type 2 and
type 6 triggers for the watchpoints.

This commit also changes the behavior of looping the triggers. In
previous implementation, if we have a type 2 trigger and
env->virt_enabled is true, we directly return false to stop the loop.
Now we keep looping all the triggers until we find a matched trigger.

Only load/store bits and loaded/stored address should be further checked
in riscv_cpu_debug_check_watchpoint().

Signed-off-by: Alvin Chang <alvinga@andestech.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240626132247.2761286-3-alvinga@andestech.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-27 12:25:09 +10:00
Alvin Chang
5e20b88953 target/riscv: Add functions for common matching conditions of trigger
According to RISC-V Debug specification version 0.13 [1] (also applied
to version 1.0 [2] but it has not been ratified yet), there are several
common matching conditions before firing a trigger, including the
enabled privilege levels of the trigger.

This commit adds trigger_common_match() to prepare the common matching
conditions for the type 2/3/6 triggers. For now, we just implement
trigger_priv_match() to check if the enabled privilege levels of the
trigger match CPU's current privilege level.

Remove the related code in riscv_cpu_debug_check_breakpoint() and invoke
trigger_common_match() to check the privilege levels of the type 2 and
type 6 triggers for the breakpoints.

This commit also changes the behavior of looping the triggers. In
previous implementation, if we have a type 2 trigger and
env->virt_enabled is true, we directly return false to stop the loop.
Now we keep looping all the triggers until we find a matched trigger.

Only the execution bit and the executed PC should be futher checked in
riscv_cpu_debug_check_breakpoint().

[1]: https://github.com/riscv/riscv-debug-spec/releases/tag/task_group_vote
[2]: https://github.com/riscv/riscv-debug-spec/releases/tag/1.0.0-rc1-asciidoc

Signed-off-by: Alvin Chang <alvinga@andestech.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240626132247.2761286-2-alvinga@andestech.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-27 12:23:33 +10:00
Frank Chang
cb5b50d91d target/riscv: Remove extension auto-update check statements
Remove the old-fashioned extension auto-update check statements as
they are replaced by the extension implied rules.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jerry Zhang Jian <jerry.zhangjian@sifive.com>
Tested-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240625114629.27793-7-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 23:15:33 +10:00
Frank Chang
3dd2168c33 target/riscv: Add Zc extension implied rule
Zc extension has special implied rules that need to be handled separately.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jerry Zhang Jian <jerry.zhangjian@sifive.com>
Tested-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240625114629.27793-6-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 23:12:21 +10:00
Frank Chang
340c3ca5f2 target/riscv: Add multi extension implied rules
Add multi extension implied rules to enable the implied extensions of
the multi extension recursively.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jerry Zhang Jian <jerry.zhangjian@sifive.com>
Tested-by: Max Chou <max.chou@sifive.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240625114629.27793-5-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 23:10:47 +10:00
Frank Chang
171773391a target/riscv: Add MISA extension implied rules
Add MISA extension implied rules to enable the implied extensions
of MISA recursively.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jerry Zhang Jian <jerry.zhangjian@sifive.com>
Tested-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240625114629.27793-4-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 23:09:12 +10:00
Frank Chang
047da861f9 target/riscv: Introduce extension implied rule helpers
Introduce helpers to enable the extensions based on the implied rules.
The implied extensions are enabled recursively, so we don't have to
expand all of them manually. This also eliminates the old-fashioned
ordering requirement. For example, Zvksg implies Zvks, Zvks implies
Zvksed, etc., removing the need to check the implied rules of Zvksg
before Zvks.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jerry Zhang Jian <jerry.zhangjian@sifive.com>
Tested-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240625114629.27793-3-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 23:07:35 +10:00
Frank Chang
f04f770920 target/riscv: Introduce extension implied rules definition
RISCVCPUImpliedExtsRule is created to store the implied rules.
'is_misa' flag is used to distinguish whether the rule is derived
from the MISA or other extensions.
'ext' stores the MISA bit if 'is_misa' is true. Otherwise, it stores
the offset of the extension defined in RISCVCPUConfig. 'ext' will also
serve as the key of the hash tables to look up the rule in the following
commit.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jerry Zhang Jian <jerry.zhangjian@sifive.com>
Tested-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240625114629.27793-2-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 23:06:00 +10:00
Clément Léger
c165408779 target/riscv: fix instructions count handling in icount mode
When icount is enabled, rather than returning the virtual CPU time, we
should return the instruction count itself. Add an instructions bool
parameter to get_ticks() to correctly return icount_get_raw() when
icount_enabled() == 1 and instruction count is queried. This will modify
the existing behavior which was returning an instructions count close to
the number of cycles (CPI ~= 1).

Signed-off-by: Clément Léger <cleger@rivosinc.com>

Reviewed-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20240618112649.76683-1-cleger@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 23:04:11 +10:00
Branislav Brzak
209b7c2935 target/riscv: Fix froundnx.h nanbox check
helper_froundnx_h function mistakenly uses single percision nanbox
check instead of the half percision one. This patch fixes the issue.

Signed-off-by: Branislav Brzak <brzakbranislav@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20240608214546.226963-1-brzakbranislav@gmail.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 23:02:35 +10:00
Fea.Wang
3adf4def19 target/riscv: Support the version for ss1p13
Add RISC-V privilege 1.13 support.

Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Weiwei Li <liwei1518@gmail.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20240606135454.119186-7-fea.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:59:25 +10:00
Fea.Wang
8392a7c148 target/riscv: Reserve exception codes for sw-check and hw-err
Based on the priv-1.13.0, add the exception codes for Software-check and
Hardware-error.

Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240606135454.119186-6-fea.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:57:49 +10:00
Fea.Wang
27796989ac target/riscv: Add MEDELEGH, HEDELEGH csrs for RV32
Based on privileged spec 1.13, the RV32 needs to implement MEDELEGH
and HEDELEGH for exception codes 32-47 for reserving and exception codes
48-63 for custom use. Add the CSR number though the implementation is
just reading zero and writing ignore. Besides, for accessing HEDELEGH, it
should be controlled by mstateen0 'P1P13' bit.

Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240606135454.119186-5-fea.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:56:01 +10:00
Fea.Wang
7750e10656 target/riscv: Add 'P1P13' bit in SMSTATEEN0
Based on privilege 1.13 spec, there should be a bit56 for 'P1P13' in
mstateen0 that controls access to the hedeleg.

Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Weiwei Li <liwei1518@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240606135454.119186-4-fea.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:54:13 +10:00
Fea.Wang
0c2d5f7396 target/riscv: Define macros and variables for ss1p13
Add macros and variables for RISC-V privilege 1.13 support.

Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Weiwei Li <liwei1518@gmail.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240606135454.119186-3-fea.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:52:24 +10:00
Jim Shu
a1a8e7768f target/riscv: Reuse the conversion function of priv_spec
Public the conversion function of priv_spec in cpu.h, so that tcg-cpu.c
could also use it.

Signed-off-by: Jim Shu <jim.shu@sifive.com>
Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240606135454.119186-2-fea.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:50:37 +10:00
Chao Du
b60520392d target/riscv/kvm: handle the exit with debug reason
If the breakpoint belongs to the userspace then set the ret value.

Signed-off-by: Chao Du <duchao@eswincomputing.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240606014501.20763-3-duchao@eswincomputing.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:46:48 +10:00
Chao Du
80b605056d target/riscv/kvm: add software breakpoints support
This patch implements insert/remove software breakpoint process.

For RISC-V, GDB treats single-step similarly to breakpoint: add a
breakpoint at the next step address, then continue. So this also
works for single-step debugging.

Implement kvm_arch_update_guest_debug(): Set the control flag
when there are active breakpoints. This will help KVM to know
the status in the userspace.

Add some stubs which are necessary for building, and will be
implemented later.

Signed-off-by: Chao Du <duchao@eswincomputing.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240606014501.20763-2-duchao@eswincomputing.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:45:14 +10:00
Jerry Zhang Jian
15b8ddb18a target/riscv: zvbb implies zvkb
According to RISC-V crypto spec, Zvkb extension is a
subset of the Zvbb extension [1].

1: 1769c2609b/doc/vector/riscv-crypto-vector-zvkb.adoc (L10)

Signed-off-by: Jerry Zhang Jian <jerry.zhangjian@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240528130349.20193-1-jerry.zhangjian@sifive.com>
[ Changes by AF:
 - Tidy up commit message
 - Rebase
]
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:30:52 +10:00
Rajnesh Kanwal
92c82a126e target/riscv: Move Guest irqs out of the core local irqs range.
Qemu maps IRQs 0:15 for core interrupts and 16 onward for
guest interrupts which are later translated to hgiep in
`riscv_cpu_set_irq()` function.

With virtual IRQ support added, software now can fully
use the whole local interrupt range without any actual
hardware attached.

This change moves the guest interrupt range after the
core local interrupt range to avoid clash.

Fixes: 1697837ed9 ("target/riscv: Add M-mode virtual interrupt and IRQ filtering support.")
Fixes: 40336d5b1d ("target/riscv: Add HS-mode virtual interrupt and IRQ filtering support.")

Signed-off-by: Rajnesh Kanwal <rkanwal@rivosinc.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240520125157.311503-3-rkanwal@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:29:17 +10:00
Rajnesh Kanwal
87088fadb3 target/riscv: Extend virtual irq csrs masks to be 64 bit wide.
AIA extends the width of all IRQ CSRs to 64bit even
in 32bit systems by adding missing half CSRs.

This seems to be missed while adding support for
virtual IRQs. The whole logic seems to be correct
except the width of the masks.

Fixes: 1697837ed9 ("target/riscv: Add M-mode virtual interrupt and IRQ filtering support.")
Fixes: 40336d5b1d ("target/riscv: Add HS-mode virtual interrupt and IRQ filtering support.")

Signed-off-by: Rajnesh Kanwal <rkanwal@rivosinc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240520125157.311503-2-rkanwal@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-26 22:27:37 +10:00
Richard Henderson
d16cab541a Misc HW & accelerators patch queue
- Use async exit in debugexit model (Thomas)
 - Fixed bug reading xlnx_dpdma descriptor (Peter)
 - Initialise plugin state before vCPU/thread creation (Alex)
 - Few sprintf() calls removed (Richard & Philippe)
 - Few deprecated QMP events removed (Philippe)
 - Housekeeping in Xen (Edgar & Philippe)
 - Split USB HID/HUB & update MAINTAINERS (Gerd)
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Merge tag 'hw-misc-accel-20240604' of https://github.com/philmd/qemu into staging

Misc HW & accelerators patch queue

- Use async exit in debugexit model (Thomas)
- Fixed bug reading xlnx_dpdma descriptor (Peter)
- Initialise plugin state before vCPU/thread creation (Alex)
- Few sprintf() calls removed (Richard & Philippe)
- Few deprecated QMP events removed (Philippe)
- Housekeeping in Xen (Edgar & Philippe)
- Split USB HID/HUB & update MAINTAINERS (Gerd)

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# gpg: Signature made Tue 04 Jun 2024 04:54:27 AM CDT
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* tag 'hw-misc-accel-20240604' of https://github.com/philmd/qemu: (32 commits)
  usb: add config options for the hub and hid devices
  qga: Remove deprecated 'blacklist' argument / config key
  trace: Remove deprecated 'vcpu' field from QMP trace events
  hw/acpi: Remove the deprecated QAPI MEM_UNPLUG_ERROR event
  hw/dma/xlnx_dpdma: Read descriptor into buffer, not into pointer-to-buffer
  hw/misc/debugexit: use runstate API instead of plain exit()
  hw/xen: Register framebuffer backend via xen_backend_init()
  hw/xen: Make XenDevOps structures const
  hw/xen: Constify xenstore_be::XenDevOps
  hw/xen: Constify XenLegacyDevice::XenDevOps
  physmem: Replace check for RAMBlock offset 0 with xen_mr_is_memory
  physmem: Always pass offset + addr to xen_map_cache
  xen: Add xen_mr_is_memory()
  core/cpu-common: initialise plugin state before thread creation
  plugins: remove special casing for cpu->realized
  cpu-target: don't set cpu->thread_id to bogus value
  cpu: move Qemu[Thread|Cond] setup into common code
  hw/core: expand on the alignment of CPUState
  accel/kvm: Fix two lines with hard-coded tabs
  accel/tcg: Move common declarations to 'internal-common.h'
  ...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-06-04 14:53:05 -05:00
Philippe Mathieu-Daudé
2dd3174990 target/riscv: Restrict riscv_cpu_do_interrupt() to sysemu
riscv_cpu_do_interrupt() is not reachable on user emulation.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230626232007.8933-7-philmd@linaro.org>
2024-06-04 10:02:39 +02:00
Philippe Mathieu-Daudé
14482b1360 target/riscv: Restrict 'rv128' machine to TCG accelerator
We only build for 32/64-bit hosts, so TCG is required for
128-bit targets.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230626232007.8933-5-philmd@linaro.org>
2024-06-04 10:02:39 +02:00
Philippe Mathieu-Daudé
7106121d26 target/riscv: Remove unused 'instmap.h' header in translate.c
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230626232007.8933-2-philmd@linaro.org>
2024-06-04 10:02:39 +02:00
Daniel Henrique Barboza
583edc4efb riscv, gdbstub.c: fix reg_width in ricsv_gen_dynamic_vector_feature()
Commit 33a24910ae changed 'reg_width' to use 'vlenb', i.e. vector length
in bytes, when in this context we want 'reg_width' as the length in
bits.

Fix 'reg_width' back to the value in bits like 7cb59921c0
("target/riscv/gdbstub.c: use 'vlenb' instead of shifting 'vlen'") set
beforehand.

While we're at it, rename 'reg_width' to 'bitsize' to provide a bit more
clarity about what the variable represents. 'bitsize' is also used in
riscv_gen_dynamic_csr_feature() with the same purpose, i.e. as an input to
gdb_feature_builder_append_reg().

Cc: Akihiko Odaki <akihiko.odaki@daynix.com>
Cc: Alex Bennée <alex.bennee@linaro.org>
Reported-by: Robin Dapp <rdapp.gcc@gmail.com>
Fixes: 33a24910ae ("target/riscv: Use GDBFeature for dynamic XML")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-ID: <20240517203054.880861-2-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Yong-Xuan Wang
190b867f28 target/riscv/kvm.c: Fix the hart bit setting of AIA
In AIA spec, each hart (or each hart within a group) has a unique hart
number to locate the memory pages of interrupt files in the address
space. The number of bits required to represent any hart number is equal
to ceil(log2(hmax + 1)), where hmax is the largest hart number among
groups.

However, if the largest hart number among groups is a power of 2, QEMU
will pass an inaccurate hart-index-bit setting to Linux. For example, when
the guest OS has 4 harts, only ceil(log2(3 + 1)) = 2 bits are sufficient
to represent 4 harts, but we passes 3 to Linux. The code needs to be
updated to ensure accurate hart-index-bit settings.

Additionally, a Linux patch[1] is necessary to correctly recover the hart
index when the guest OS has only 1 hart, where the hart-index-bit is 0.

[1] https://lore.kernel.org/lkml/20240415064905.25184-1-yongxuan.wang@sifive.com/t/

Signed-off-by: Yong-Xuan Wang <yongxuan.wang@sifive.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-ID: <20240515091129.28116-1-yongxuan.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Alistair Francis
c5eb8d6336 target/riscv: rvzicbo: Fixup CBO extension register calculation
When running the instruction

```
    cbo.flush 0(x0)
```

QEMU would segfault.

The issue was in cpu_gpr[a->rs1] as QEMU does not have cpu_gpr[0]
allocated.

In order to fix this let's use the existing get_address()
helper. This also has the benefit of performing pointer mask
calculations on the address specified in rs1.

The pointer masking specificiation specifically states:

"""
Cache Management Operations: All instructions in Zicbom, Zicbop and Zicboz
"""

So this is the correct behaviour and we previously have been incorrectly
not masking the address.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reported-by: Fabian Thomas <fabian.thomas@cispa.de>
Fixes: e05da09b7c ("target/riscv: implement Zicbom extension")
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-ID: <20240514023910.301766-1-alistair.francis@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Rob Bradford
73ef14b127 target/riscv: Remove experimental prefix from "B" extension
This extension has now been ratified:
https://jira.riscv.org/browse/RVS-2006 so the "x-" prefix can be
removed.

Since this is now a ratified extension add it to the list of extensions
included in the "max" CPU variant.

Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-ID: <20240514110217.22516-1-rbradford@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Alexei Filippov
6c9a344247 target/riscv: do not set mtval2 for non guest-page faults
Previous patch fixed the PMP priority in raise_mmu_exception() but we're still
setting mtval2 incorrectly. In riscv_cpu_tlb_fill(), after pmp check in 2 stage
translation part, mtval2 will be set in case of successes 2 stage translation but
failed pmp check.

In this case we gonna set mtval2 via env->guest_phys_fault_addr in context of
riscv_cpu_tlb_fill(), as this was a guest-page-fault, but it didn't and mtval2
should be zero, according to RISCV privileged spec sect. 9.4.4: When a guest
page-fault is taken into M-mode, mtval2 is written with either zero or guest
physical address that faulted, shifted by 2 bits. *For other traps, mtval2
is set to zero...*

Signed-off-by: Alexei Filippov <alexei.filippov@syntacore.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240503103052.6819-1-alexei.filippov@syntacore.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Daniel Henrique Barboza
68e7c86927 target/riscv: prioritize pmp errors in raise_mmu_exception()
raise_mmu_exception(), as is today, is prioritizing guest page faults by
checking first if virt_enabled && !first_stage, and then considering the
regular inst/load/store faults.

There's no mention in the spec about guest page fault being a higher
priority that PMP faults. In fact, privileged spec section 3.7.1 says:

"Attempting to fetch an instruction from a PMP region that does not have
execute permissions raises an instruction access-fault exception.
Attempting to execute a load or load-reserved instruction which accesses
a physical address within a PMP region without read permissions raises a
load access-fault exception. Attempting to execute a store,
store-conditional, or AMO instruction which accesses a physical address
within a PMP region without write permissions raises a store
access-fault exception."

So, in fact, we're doing it wrong - PMP faults should always be thrown,
regardless of also being a first or second stage fault.

The way riscv_cpu_tlb_fill() and get_physical_address() work is
adequate: a TRANSLATE_PMP_FAIL error is immediately reported and
reflected in the 'pmp_violation' flag. What we need is to change
raise_mmu_exception() to prioritize it.

Reported-by: Joseph Chan <jchan@ventanamicro.com>
Fixes: 82d53adfbb ("target/riscv/cpu_helper.c: Invalid exception on MMU translation stage")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240413105929.7030-1-alexei.filippov@syntacore.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Max Chou
93cb52b7a3 target/riscv: rvv: Remove redudant SEW checking for vector fp narrow/widen instructions
If the checking functions check both the single and double width
operators at the same time, then the single width operator checking
functions (require_rvf[min]) will check whether the SEW is 8.

Signed-off-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-ID: <20240322092600.1198921-5-max.chou@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Max Chou
692f33a3ab target/riscv: rvv: Check single width operator for vfncvt.rod.f.f.w
The opfv_narrow_check needs to check the single width float operator by
require_rvf.

Signed-off-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-ID: <20240322092600.1198921-4-max.chou@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Max Chou
7a999d4dd7 target/riscv: rvv: Check single width operator for vector fp widen instructions
The require_scale_rvf function only checks the double width operator for
the vector floating point widen instructions, so most of the widen
checking functions need to add require_rvf for single width operator.

The vfwcvt.f.x.v and vfwcvt.f.xu.v instructions convert single width
integer to double width float, so the opfxv_widen_check function doesn’t
need require_rvf for the single width operator(integer).

Signed-off-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-ID: <20240322092600.1198921-3-max.chou@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Max Chou
17b713c080 target/riscv: rvv: Fix Zvfhmin checking for vfwcvt.f.f.v and vfncvt.f.f.w instructions
According v spec 18.4, only the vfwcvt.f.f.v and vfncvt.f.f.w
instructions will be affected by Zvfhmin extension.
And the vfwcvt.f.f.v and vfncvt.f.f.w instructions only support the
conversions of

* From 1*SEW(16/32) to 2*SEW(32/64)
* From 2*SEW(32/64) to 1*SEW(16/32)

Signed-off-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-ID: <20240322092600.1198921-2-max.chou@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Christoph Müllner
fd53ee268d riscv: thead: Add th.sxstatus CSR emulation
The th.sxstatus CSR can be used to identify available custom extension
on T-Head CPUs. The CSR is documented here:
  https://github.com/T-head-Semi/thead-extension-spec/blob/master/xtheadsxstatus.adoc

An important property of this patch is, that the th.sxstatus MAEE field
is not set (indicating that XTheadMae is not available).
XTheadMae is a memory attribute extension (similar to Svpbmt) which is
implemented in many T-Head CPUs (C906, C910, etc.) and utilizes bits
in PTEs that are marked as reserved. QEMU maintainers prefer to not
implement XTheadMae, so we need give kernels a mechanism to identify
if XTheadMae is available in a system or not. And this patch introduces
this mechanism in QEMU in a way that's compatible with real HW
(i.e., probing the th.sxstatus.MAEE bit).

Further context can be found on the list:
https://lists.gnu.org/archive/html/qemu-devel/2024-02/msg00775.html

Reviewed-by: LIU Zhiwei <zhiwe_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>
Message-ID: <20240429073656.2486732-1-christoph.muellner@vrull.eu>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Huang Tao
8c8a7cd647 target/riscv: Implement dynamic establishment of custom decoder
In this patch, we modify the decoder to be a freely composable data
structure instead of a hardcoded one. It can be dynamically builded up
according to the extensions.
This approach has several benefits:
1. Provides support for heterogeneous cpu architectures. As we add decoder in
   RISCVCPU, each cpu can have their own decoder, and the decoders can be
   different due to cpu's features.
2. Improve the decoding efficiency. We run the guard_func to see if the decoder
   can be added to the dynamic_decoder when building up the decoder. Therefore,
   there is no need to run the guard_func when decoding each instruction. It can
   improve the decoding efficiency
3. For vendor or dynamic cpus, it allows them to customize their own decoder
   functions to improve decoding efficiency, especially when vendor-defined
   instruction sets increase. Because of dynamic building up, it can skip the other
   decoder guard functions when decoding.
4. Pre patch for allowing adding a vendor decoder before decode_insn32() with minimal
   overhead for users that don't need this particular vendor decoder.

Signed-off-by: Huang Tao <eric.huang@linux.alibaba.com>
Suggested-by: Christoph Muellner <christoph.muellner@vrull.eu>
Co-authored-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240506023607.29544-1-eric.huang@linux.alibaba.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Yangyu Chen
ff33b7a969 target/riscv/cpu.c: fix Zvkb extension config
This code has a typo that writes zvkb to zvkg, causing users can't
enable zvkb through the config. This patch gets this fixed.

Signed-off-by: Yangyu Chen <cyy@cyyself.name>
Fixes: ea61ef7097 ("target/riscv: Move vector crypto extensions to riscv_cpu_extensions")
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Max Chou <max.chou@sifive.com>
Reviewed-by:  Weiwei Li <liwei1518@gmail.com>
Message-ID: <tencent_7E34EEF0F90B9A68BF38BEE09EC6D4877C0A@qq.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Huang Tao
75115d880c target/riscv: Fix the element agnostic function problem
In RVV and vcrypto instructions, the masked and tail elements are set to 1s
using vext_set_elems_1s function if the vma/vta bit is set. It is the element
agnostic policy.

However, this function can't deal the big endian situation. This patch fixes
the problem by adding handling of such case.

Signed-off-by: Huang Tao <eric.huang@linux.alibaba.com>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-ID: <20240325021654.6594-1-eric.huang@linux.alibaba.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Jason Chien
4a90991234 target/riscv: Relax vector register check in RISCV gdbstub
In current implementation, the gdbstub allows reading vector registers
only if V extension is supported. However, all vector extensions and
vector crypto extensions have the vector registers and they all depend
on Zve32x. The gdbstub should check for Zve32x instead.

Signed-off-by: Jason Chien <jason.chien@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Max Chou <max.chou@sifive.com>
Message-ID: <20240328022343.6871-4-jason.chien@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Jason Chien
e7dc5e160f target/riscv: Add support for Zve64x extension
Add support for Zve64x extension. Enabling Zve64f enables Zve64x and
enabling Zve64x enables Zve32x according to their dependency.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2107
Signed-off-by: Jason Chien <jason.chien@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240328022343.6871-3-jason.chien@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Jason Chien
9fb41a4418 target/riscv: Add support for Zve32x extension
Add support for Zve32x extension and replace some checks for Zve32f with
Zve32x, since Zve32f depends on Zve32x.

Signed-off-by: Jason Chien <jason.chien@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Max Chou <max.chou@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240328022343.6871-2-jason.chien@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Daniel Henrique Barboza
f15af01740 trans_privileged.c.inc: set (m|s)tval on ebreak breakpoint
Privileged spec section 4.1.9 mentions:

"When a trap is taken into S-mode, stval is written with
exception-specific information to assist software in handling the trap.
(...)

If stval is written with a nonzero value when a breakpoint,
address-misaligned, access-fault, or page-fault exception occurs on an
instruction fetch, load, or store, then stval will contain the faulting
virtual address."

A similar text is found for mtval in section 3.1.16.

Setting mtval/stval in this scenario is optional, but some softwares read
these regs when handling ebreaks.

Write 'badaddr' in all ebreak breakpoints to write the appropriate
'tval' during riscv_do_cpu_interrrupt().

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: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20240416230437.1869024-3-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Daniel Henrique Barboza
0099f60534 target/riscv/debug: set tval=pc in breakpoint exceptions
We're not setting (s/m)tval when triggering breakpoints of type 2
(mcontrol) and 6 (mcontrol6). According to the debug spec section
5.7.12, "Match Control Type 6":

"The Privileged Spec says that breakpoint exceptions that occur on
instruction fetches, loads, or stores update the tval CSR with either
zero or the faulting virtual address. The faulting virtual address for
an mcontrol6 trigger with action = 0 is the address being accessed and
which caused that trigger to fire."

A similar text is also found in the Debug spec section 5.7.11 w.r.t.
mcontrol.

Note that what we're doing ATM is not violating the spec, but it's
simple enough to set mtval/stval and it makes life easier for any
software that relies on this info.

Given that we always use action = 0, save the faulting address for the
mcontrol and mcontrol6 trigger breakpoints into env->badaddr, which is
used as as scratch area for traps with address information. 'tval' is
then set during riscv_cpu_do_interrupt().

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>
Message-ID: <20240416230437.1869024-2-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Daniel Henrique Barboza
1215d45b2a target/riscv/kvm: tolerate KVM disable ext errors
Running a KVM guest using a 6.9-rc3 kernel, in a 6.8 host that has zkr
enabled, will fail with a kernel oops SIGILL right at the start. The
reason is that we can't expose zkr without implementing the SEED CSR.
Disabling zkr in the guest would be a workaround, but if the KVM doesn't
allow it we'll error out and never boot.

In hindsight this is too strict. If we keep proceeding, despite not
disabling the extension in the KVM vcpu, we'll not add the extension in
the riscv,isa. The guest kernel will be unaware of the extension, i.e.
it doesn't matter if the KVM vcpu has it enabled underneath or not. So
it's ok to keep booting in this case.

Change our current logic to not error out if we fail to disable an
extension in kvm_set_one_reg(), but show a warning and keep booting. It
is important to throw a warning because we must make the user aware that
the extension is still available in the vcpu, meaning that an
ill-behaved guest can ignore the riscv,isa settings and  use the
extension.

The case we're handling happens with an EINVAL error code. If we fail to
disable the extension in KVM for any other reason, error out.

We'll also keep erroring out when we fail to enable an extension in KVM,
since adding the extension in riscv,isa at this point will cause a guest
malfunction because the extension isn't enabled in the vcpu.

Suggested-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-ID: <20240422171425.333037-2-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:12 +10:00
Clément Léger
ba7a1c5297 target/riscv: change RISCV_EXCP_SEMIHOST exception number to 63
The current semihost exception number (16) is a reserved number (range
[16-17]). The upcoming double trap specification uses that number for
the double trap exception. Since the privileged spec (Table 22) defines
ranges for custom uses change the semihosting exception number to 63
which belongs to the range [48-63] in order to avoid any future
collisions with reserved exception.

Signed-off-by: Clément Léger <cleger@rivosinc.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240422135840.1959967-1-cleger@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:11 +10:00
Daniel Henrique Barboza
a6b53378f5 target/riscv/kvm: implement SBI debug console (DBCN) calls
SBI defines a Debug Console extension "DBCN" that will, in time, replace
the legacy console putchar and getchar SBI extensions.

The appeal of the DBCN extension is that it allows multiple bytes to be
read/written in the SBI console in a single SBI call.

As far as KVM goes, the DBCN calls are forwarded by an in-kernel KVM
module to userspace. But this will only happens if the KVM module
actually supports this SBI extension and we activate it.

We'll check for DBCN support during init time, checking if get-reg-list
is advertising KVM_RISCV_SBI_EXT_DBCN. In that case, we'll enable it via
kvm_set_one_reg() during kvm_arch_init_vcpu().

Finally, change kvm_riscv_handle_sbi() to handle the incoming calls for
SBI_EXT_DBCN, reading and writing as required.

A simple KVM guest with 'earlycon=sbi', running in an emulated RISC-V
host, takes around 20 seconds to boot without using DBCN. With this
patch we're taking around 14 seconds to boot due to the speed-up in the
terminal output.  There's no change in boot time if the guest isn't
using earlycon.

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20240425155012.581366-1-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:11 +10:00
Andrew Jones
b62e0ce760 target/riscv: Raise exceptions on wrs.nto
Implementing wrs.nto to always just return is consistent with the
specification, as the instruction is permitted to terminate the
stall for any reason, but it's not useful for virtualization, where
we'd like the guest to trap to the hypervisor in order to allow
scheduling of the lock holding VCPU. Change to always immediately
raise exceptions when the appropriate conditions are present,
otherwise continue to just return. Note, immediately raising
exceptions is also consistent with the specification since the
time limit that should expire prior to the exception is
implementation-specific.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Christoph Müllner <christoph.muellner@vrull.eu>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240424142808.62936-2-ajones@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-06-03 11:12:11 +10:00