We're about to allow guests to use the Zicboz extension. KVM
userspace needs to know the cache block size in order to
properly advertise it to the guest. Provide a virtual config
register for userspace to get it with the GET_ONE_REG API, but
setting it cannot be supported, so disallow SET_ONE_REG.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20230224162631.405473-8-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
unsigned long mvendorid;
unsigned long marchid;
unsigned long mimpid;
+ unsigned long zicboz_block_size;
};
/* CORE registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
return -EINVAL;
reg_val = riscv_cbom_block_size;
break;
+ case KVM_REG_RISCV_CONFIG_REG(zicboz_block_size):
+ if (!riscv_isa_extension_available(vcpu->arch.isa, ZICBOZ))
+ return -EINVAL;
+ reg_val = riscv_cboz_block_size;
+ break;
case KVM_REG_RISCV_CONFIG_REG(mvendorid):
reg_val = vcpu->arch.mvendorid;
break;
break;
case KVM_REG_RISCV_CONFIG_REG(zicbom_block_size):
return -EOPNOTSUPP;
+ case KVM_REG_RISCV_CONFIG_REG(zicboz_block_size):
+ return -EOPNOTSUPP;
case KVM_REG_RISCV_CONFIG_REG(mvendorid):
if (!vcpu->arch.ran_atleast_once)
vcpu->arch.mvendorid = reg_val;