Re: [PATCH] target/riscv/kvm: Fix the group bit setting of AIA

[Daniel Henrique Barboza]

On 8/21/24 4:50 AM, Andrew Jones wrote:
> Just as the hart bit setting of the AIA should be calculated as
> ceil(log2(max_hart_id + 1)) the group bit setting should be
> calculated as ceil(log2(max_group_id + 1)). The hart bits are
> implemented by passing max_hart_id to find_last_bit() and adding
> one to the result. Do the same for the group bit setting.
>
> Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
> ---

Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>

>   target/riscv/kvm/kvm-cpu.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/target/riscv/kvm/kvm-cpu.c b/target/riscv/kvm/kvm-cpu.c
> index f6e3156b8d2f..341af901c5b0 100644
> --- a/target/riscv/kvm/kvm-cpu.c
> +++ b/target/riscv/kvm/kvm-cpu.c
> @@ -1695,6 +1695,7 @@ void kvm_riscv_aia_create(MachineState *machine, uint64_t 
> group_shift,
>       uint64_t max_hart_per_socket = 0;
>       uint64_t socket, base_hart, hart_count, socket_imsic_base, imsic_addr;
>       uint64_t socket_bits, hart_bits, guest_bits;
> +    uint64_t max_group_id;
>   
>       aia_fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_RISCV_AIA, false);
>   
> @@ -1742,7 +1743,8 @@ void kvm_riscv_aia_create(MachineState *machine, uint64_t group_shift,
>   
>   
>       if (socket_count > 1) {
> -        socket_bits = find_last_bit(&socket_count, BITS_PER_LONG) + 1;
> +        max_group_id = socket_count - 1;
> +        socket_bits = find_last_bit(&max_group_id, BITS_PER_LONG) + 1;
>           ret = kvm_device_access(aia_fd, KVM_DEV_RISCV_AIA_GRP_CONFIG,
>                                   KVM_DEV_RISCV_AIA_CONFIG_GROUP_BITS,
>                                   &socket_bits, true, NULL);