Commit Graph

7 Commits

Author SHA1 Message Date
liguang.zhang
8633951530 target/riscv: Clear CSR values at reset and sync MPSTATE with host
This patch fixes guest reboot errors when using KVM.

There are two issues when rebooting a guest using KVM
1. When the guest initiates a reboot the host is unable to stop the vcpu
2. When running a SMP guest the qemu monitor system_reset causes a vcpu crash

This can be fixed by clearing the CSR values at reset and syncing the
MPSTATE with the host.

Signed-off-by: liguang.zhang <liguang.zhang@hexintek.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20230913091332.17355-1-18622748025@163.com>
[ Changes by AF
 - Fixup commit message
 - Fixup patch style
]
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2023-10-12 11:52:43 +10:00
Daniel Henrique Barboza
68aba1f2af target/riscv/cpu.c: split kvm prop handling to its own helper
Future patches will split the existing Property arrays even further, and
the existing code in riscv_cpu_add_user_properties() will start to scale
bad with it because it's dealing with KVM constraints mixed in with TCG
constraints. We're going to pay a high price to share a couple of common
lines of code between the two.

Create a new kvm_riscv_cpu_add_kvm_properties() helper that will be
forked from riscv_cpu_add_user_properties() if we're running KVM. The
helper includes all properties that a KVM CPU will add. The rest of
riscv_cpu_add_user_properties() body will then be relieved from having
to deal with KVM constraints.

The helper was declared in kvm_stubs.h, while being implemented in
cpu.c, to allow '--enable-debug' builds to work. The compiler won't
remove the kvm_riscv_cpu_add_kvm_properties() reference when
'kvm_enabled()' is false if we end up with an unused function. Even
though being a KVM only helper we can't implement it in kvm.c due to its
many dependencies inside cpu.c, so make it public in kvm_riscv.h and
keep its implementation in cpu.c for now. We'll move it to kvm.c in the
near future.

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230912132423.268494-4-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2023-10-12 11:31:38 +10:00
Daniel Henrique Barboza
b815664091 hw/intc/riscv_aplic.c fix non-KVM --enable-debug build
Commit 6df0b37e2ab breaks a --enable-debug build in a non-KVM
environment with the following error:

/usr/bin/ld: libqemu-riscv64-softmmu.fa.p/hw_intc_riscv_aplic.c.o: in function `riscv_kvm_aplic_request':
./qemu/build/../hw/intc/riscv_aplic.c:486: undefined reference to `kvm_set_irq'
collect2: error: ld returned 1 exit status

This happens because the debug build will poke into the
'if (is_kvm_aia(aplic->msimode))' block and fail to find a reference to
the KVM only function riscv_kvm_aplic_request().

There are multiple solutions to fix this. We'll go with the same
solution from the previous patch, i.e. add a kvm_enabled() conditional
to filter out the block. But there's a catch: riscv_kvm_aplic_request()
is a local function that would end up being used if the compiler crops
the block, and this won't work. Quoting Richard Henderson's explanation
in [1]:

"(...) the compiler won't eliminate entire unused functions with -O0"

We'll solve it by moving riscv_kvm_aplic_request() to kvm.c and add its
declaration in kvm_riscv.h, where all other KVM specific public
functions are already declared. Other archs handles KVM specific code in
this manner and we expect to do the same from now on.

[1] https://lore.kernel.org/qemu-riscv/d2f1ad02-eb03-138f-9d08-db676deeed05@linaro.org/

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20230830133503.711138-3-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2023-09-11 11:45:55 +10:00
Yong-Xuan Wang
9634ef7eda target/riscv: Create an KVM AIA irqchip
We create a vAIA chip by using the KVM_DEV_TYPE_RISCV_AIA and then set up
the chip with the KVM_DEV_RISCV_AIA_GRP_* APIs.
We also extend KVM accelerator to specify the KVM AIA mode. The "riscv-aia"
parameter is passed along with --accel in QEMU command-line.
1) "riscv-aia=emul": IMSIC is emulated by hypervisor
2) "riscv-aia=hwaccel": use hardware guest IMSIC
3) "riscv-aia=auto": use the hardware guest IMSICs whenever available
                     otherwise we fallback to software emulation.

Signed-off-by: Yong-Xuan Wang <yongxuan.wang@sifive.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Message-ID: <20230727102439.22554-4-yongxuan.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2023-09-11 11:45:55 +10:00
Daniel Henrique Barboza
492265ae8b target/riscv: use KVM scratch CPUs to init KVM properties
Certain validations, such as the validations done for the machine IDs
(mvendorid/marchid/mimpid), are done before starting the CPU.
Non-dynamic (named) CPUs tries to match user input with a preset
default. As it is today we can't prefetch a KVM default for these cases
because we're only able to read/write KVM regs after the vcpu is
spinning.

Our target/arm friends use a concept called "scratch CPU", which
consists of creating a vcpu for doing queries and validations and so on,
which is discarded shortly after use [1]. This is a suitable solution
for what we need so let's implement it in target/riscv as well.

kvm_riscv_init_machine_ids() will be used to do any pre-launch setup for
KVM CPUs, via riscv_cpu_add_user_properties(). The function will create
a KVM scratch CPU, fetch KVM regs that work as default values for user
properties, and then discard the scratch CPU afterwards.

We're starting by initializing 'mvendorid'. This concept will be used to
init other KVM specific properties in the next patches as well.

[1] target/arm/kvm.c, kvm_arm_create_scratch_host_vcpu()

Suggested-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230706101738.460804-7-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2023-07-10 22:29:15 +10:00
Yifei Jiang
2b650fbbcc target/riscv: Support setting external interrupt by KVM
When KVM is enabled, set the S-mode external interrupt through
kvm_riscv_set_irq function.

Signed-off-by: Yifei Jiang <jiangyifei@huawei.com>
Signed-off-by: Mingwang Li <limingwang@huawei.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Message-id: 20220112081329.1835-8-jiangyifei@huawei.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2022-01-21 15:52:56 +10:00
Yifei Jiang
ad40be2708 target/riscv: Support start kernel directly by KVM
Get kernel and fdt start address in virt.c, and pass them to KVM
when cpu reset. Add kvm_riscv.h to place riscv specific interface.

In addition, PLIC is created without M-mode PLIC contexts when KVM
is enabled.

Signed-off-by: Yifei Jiang <jiangyifei@huawei.com>
Signed-off-by: Mingwang Li <limingwang@huawei.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Message-id: 20220112081329.1835-7-jiangyifei@huawei.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2022-01-21 15:52:56 +10:00