target/riscv/kvm: Fix the group bit setting of AIA

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>
Message-ID: <20240821075040.498945-2-ajones@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/target/riscv/kvm/kvm-cpu.c b/target/riscv/kvm/kvm-cpu.c
index f6e3156..341af90 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);