// cpu/src/x86_64/mod.rs
const ECX_INVALID: u32 = 0u32 << 8;
const ECX_THREAD: u32 = 1u32 << 8;
const ECX_CORE: u32 = 2u32 << 8;
const ECX_DIE: u32 = 5u32 << 8;

impl X86CPUState {
    fn setup_cpuid(&self, vcpu_fd: &Arc<VcpuFd>) -> Result<()> {
        // 计算 topology ID
        let core_offset = 32u32 - (self.nr_threads - 1).leading_zeros();
        let die_offset = (32u32 - (self.nr_cores - 1).leading_zeros()) + core_offset;
        let pkg_offset = (32u32 - (self.nr_dies - 1).leading_zeros()) + die_offset;

        // 获取 KVM 的 fd 和 获取它支持的 CPUID entries

        for entry in entries.iter_mut() {
            match entry.function {
                // ...
                0xb => {
                    // Extended Topology Enumeration Leaf
                    entry.edx = self.apic_id as u32;
                    entry.ecx = entry.index & 0xff;
                    match entry.index {
                        0 => {
                            entry.eax = core_offset;
                            entry.ebx = self.nr_threads;
                            entry.ecx |= ECX_THREAD;
                        }
                        1 => {
                            entry.eax = pkg_offset;
                            entry.ebx = self.nr_threads * self.nr_cores;
                            entry.ecx |= ECX_CORE;
                        }
                        _ => {
                            entry.eax = 0;
                            entry.ebx = 0;
                            entry.ecx |= ECX_INVALID;
                        }
                    }
                }
                // 0x1f 扩展，支持 die 层级
                0x1f => {
                    if self.nr_dies < 2 {
                        entry.eax = 0;
                        entry.ebx = 0;
                        entry.ecx = 0;
                        entry.edx = 0;
                        continue;
                    }

                    entry.edx = self.apic_id as u32;
                    entry.ecx = entry.index & 0xff;

                    match entry.index {
                        0 => {
                            entry.eax = core_offset;
                            entry.ebx = self.nr_threads;
                            entry.ecx |= ECX_THREAD;
                        }
                        1 => {
                            entry.eax = die_offset;
                            entry.ebx = self.nr_cores * self.nr_threads;
                            entry.ecx |= ECX_CORE;
                        }
                        2 => {
                            entry.eax = pkg_offset;
                            entry.ebx = self.nr_dies * self.nr_cores * self.nr_threads;
                            entry.ecx |= ECX_DIE;
                        }
                        _ => {
                            entry.eax = 0;
                            entry.ebx = 0;
                            entry.ecx |= ECX_INVALID;
                        }
                    }
                }
                // ...
            }
        }
}

// machine/src/standard_vm/aarch64/mod.rs
impl AcpiBuilder for StdMachine {
    fn build_pptt_table(
        &self,
        acpi_data: &Arc<Mutex<Vec<u8>>>,
        loader: &mut TableLoader,
    ) -> super::errors::Result<u64> {
        // ...
        // 配置 PPTT 表头

        // 添加 socket 节点
        for socket in 0..self.cpu_topo.sockets {
            // 计算到起始地址的偏移量
            let socket_offset = pptt.table_len() - pptt_start;
            let socket_hierarchy_node = ProcessorHierarchyNode::new(0, 0x2, 0, socket as u32);
            // ...
            for cluster in 0..self.cpu_topo.clusters {
                let cluster_offset = pptt.table_len() - pptt_start;
                let cluster_hierarchy_node =
                    ProcessorHierarchyNode::new(0, 0x0, socket_offset as u32, cluster as u32);
                // ...
                for core in 0..self.cpu_topo.cores {
                    let core_offset = pptt.table_len() - pptt_start;
                    // 判断是否需要添加 thread 节点
                    if self.cpu_topo.threads > 1 {
                        let core_hierarchy_node =
                            ProcessorHierarchyNode::new(0, 0x0, cluster_offset as u32, core as u32);
                        // ...
                        for _thread in 0..self.cpu_topo.threads {
                            let thread_hierarchy_node =
                                ProcessorHierarchyNode::new(0, 0xE, core_offset as u32, uid as u32);
                            // ...
                            uid += 1;
                        }
                    } else {
                        let thread_hierarchy_node =
                            ProcessorHierarchyNode::new(0, 0xA, cluster_offset as u32, uid as u32);
                        // ...
                        uid += 1;
                    }
                }
            }
        }
        // 将 PPTT 表添加到 loader 中
    }
}

impl CompileFDTHelper for LightMachine {
    fn generate_cpu_nodes(&self, fdt: &mut FdtBuilder) -> util::errors::Result<()> {
        // 创建 cpus 节点
        // ...

        // Generate CPU topology
        // 创建 cpu-map 节点
        let cpu_map_node_dep = fdt.begin_node("cpu-map")?;
        // 创建第一层 cluster 节点
        for socket in 0..self.cpu_topo.sockets {
            let sock_name = format!("cluster{}", socket);
            let sock_node_dep = fdt.begin_node(&sock_name)?;
            // 创建第二层 cluster 节点
            for cluster in 0..self.cpu_topo.clusters {
                let clster = format!("cluster{}", cluster);
                let cluster_node_dep = fdt.begin_node(&clster)?;
                // 创建 core 节点
                for core in 0..self.cpu_topo.cores {
                    let core_name = format!("core{}", core);
                    let core_node_dep = fdt.begin_node(&core_name)?;
                    // 创建 thread 节点
                    for thread in 0..self.cpu_topo.threads {
                        let thread_name = format!("thread{}", thread);
                        let thread_node_dep = fdt.begin_node(&thread_name)?;
                        // 计算 cpu 的 id
                        // let vcpuid = ...
                        // 然后添加到节点中
                    }
                    fdt.end_node(core_node_dep)?;
                }
                fdt.end_node(cluster_node_dep)?;
            }
            fdt.end_node(sock_node_dep)?;
        }
        fdt.end_node(cpu_map_node_dep)?;

        Ok(())
    }
}