xref: /DragonOS/kernel/src/driver/pci/pci.rs (revision 79a452ce8f27ad9c7283ac0bcf4078ed6fa018d7)
1 #![allow(dead_code)]
2 // 目前仅支持单主桥单Segment
3 
4 use crate::arch::{PciArch, TraitPciArch};
5 use crate::include::bindings::bindings::{
6     initial_mm, mm_map, mm_struct, PAGE_2M_SIZE, VM_DONTCOPY, VM_IO,
7 };
8 use crate::libs::rwlock::{RwLock, RwLockReadGuard, RwLockWriteGuard};
9 use crate::mm::mmio_buddy::MMIO_POOL;
10 use crate::{kdebug, kerror, kinfo, kwarn};
11 use alloc::vec::Vec;
12 use alloc::{boxed::Box, collections::LinkedList};
13 use bitflags::bitflags;
14 use core::{
15     convert::TryFrom,
16     fmt::{self, Display, Formatter},
17 };
18 // PCI_DEVICE_LINKEDLIST 添加了读写锁的全局链表,里面存储了检索到的PCI设备结构体
19 // PCI_ROOT_0 Segment为0的全局PciRoot
20 lazy_static! {
21     pub static ref PCI_DEVICE_LINKEDLIST: PciDeviceLinkedList = PciDeviceLinkedList::new();
22     pub static ref PCI_ROOT_0: Option<PciRoot> = {
23         match PciRoot::new(0) {
24             Ok(root) => Some(root),
25             Err(err) => {
26                 kerror!("Pci_root init failed because of error: {}", err);
27                 None
28             }
29         }
30     };
31 }
32 
33 /// 添加了读写锁的链表,存储PCI设备结构体
34 pub struct PciDeviceLinkedList {
35     list: RwLock<LinkedList<Box<dyn PciDeviceStructure>>>,
36 }
37 
38 impl PciDeviceLinkedList {
39     /// @brief 初始化结构体
40     fn new() -> Self {
41         PciDeviceLinkedList {
42             list: RwLock::new(LinkedList::new()),
43         }
44     }
45     /// @brief 获取可读的linkedlist(读锁守卫)
46     /// @return RwLockReadGuard<LinkedList<Box<dyn PciDeviceStructure>>>  读锁守卫
47     pub fn read(&self) -> RwLockReadGuard<LinkedList<Box<dyn PciDeviceStructure>>> {
48         self.list.read()
49     }
50     /// @brief 获取可写的linkedlist(写锁守卫)
51     /// @return RwLockWriteGuard<LinkedList<Box<dyn PciDeviceStructure>>>  写锁守卫
52     pub fn write(&self) -> RwLockWriteGuard<LinkedList<Box<dyn PciDeviceStructure>>> {
53         self.list.write()
54     }
55     /// @brief 获取链表中PCI结构体数目
56     /// @return usize 链表中PCI结构体数目
57     pub fn num(&self) -> usize {
58         let list = self.list.read();
59         list.len()
60     }
61     /// @brief 添加Pci设备结构体到链表中
62     pub fn add(&self, device: Box<dyn PciDeviceStructure>) {
63         let mut list = self.list.write();
64         list.push_back(device);
65     }
66 }
67 
68 /// @brief 在链表中寻找满足条件的PCI设备结构体并返回其可变引用
69 /// @param list 链表的写锁守卫
70 /// @param class_code 寄存器值
71 /// @param subclass 寄存器值,与class_code一起确定设备类型
72 /// @return Vec<&'a mut Box<(dyn PciDeviceStructure)  包含链表中所有满足条件的PCI结构体的可变引用的容器
73 pub fn get_pci_device_structure_mut<'a>(
74     list: &'a mut RwLockWriteGuard<'_, LinkedList<Box<dyn PciDeviceStructure>>>,
75     class_code: u8,
76     subclass: u8,
77 ) -> Vec<&'a mut Box<(dyn PciDeviceStructure)>> {
78     let mut result = Vec::new();
79     for box_pci_device_structure in list.iter_mut() {
80         let common_header = (*box_pci_device_structure).common_header();
81         if (common_header.class_code == class_code) && (common_header.subclass == subclass) {
82             result.push(box_pci_device_structure);
83         }
84     }
85     result
86 }
87 /// @brief 在链表中寻找满足条件的PCI设备结构体并返回其不可变引用
88 /// @param list 链表的读锁守卫
89 /// @param class_code 寄存器值
90 /// @param subclass 寄存器值,与class_code一起确定设备类型
91 /// @return Vec<&'a Box<(dyn PciDeviceStructure)  包含链表中所有满足条件的PCI结构体的不可变引用的容器
92 pub fn get_pci_device_structure<'a>(
93     list: &'a mut RwLockReadGuard<'_, LinkedList<Box<dyn PciDeviceStructure>>>,
94     class_code: u8,
95     subclass: u8,
96 ) -> Vec<&'a Box<(dyn PciDeviceStructure)>> {
97     let mut result = Vec::new();
98     for box_pci_device_structure in list.iter() {
99         let common_header = (*box_pci_device_structure).common_header();
100         if (common_header.class_code == class_code) && (common_header.subclass == subclass) {
101             result.push(box_pci_device_structure);
102         }
103     }
104     result
105 }
106 
107 //Bar0寄存器的offset
108 const BAR0_OFFSET: u8 = 0x10;
109 //Status、Command寄存器的offset
110 const STATUS_COMMAND_OFFSET: u8 = 0x04;
111 /// ID for vendor-specific PCI capabilities.(Virtio Capabilities)
112 pub const PCI_CAP_ID_VNDR: u8 = 0x09;
113 pub const PORT_PCI_CONFIG_ADDRESS: u16 = 0xcf8;
114 pub const PORT_PCI_CONFIG_DATA: u16 = 0xcfc;
115 // pci设备分组的id
116 pub type SegmentGroupNumber = u16; //理论上最多支持65535个Segment_Group
117 
118 bitflags! {
119     /// The status register in PCI configuration space.
120     pub struct Status: u16 {
121         // Bits 0-2 are reserved.
122         /// The state of the device's INTx# signal.
123         const INTERRUPT_STATUS = 1 << 3;
124         /// The device has a linked list of capabilities.
125         const CAPABILITIES_LIST = 1 << 4;
126         /// The device is capabile of running at 66 MHz rather than 33 MHz.
127         const MHZ_66_CAPABLE = 1 << 5;
128         // Bit 6 is reserved.
129         /// The device can accept fast back-to-back transactions not from the same agent.
130         const FAST_BACK_TO_BACK_CAPABLE = 1 << 7;
131         /// The bus agent observed a parity error (if parity error handling is enabled).
132         const MASTER_DATA_PARITY_ERROR = 1 << 8;
133         // Bits 9-10 are DEVSEL timing.
134         /// A target device terminated a transaction with target-abort.
135         const SIGNALED_TARGET_ABORT = 1 << 11;
136         /// A master device transaction was terminated with target-abort.
137         const RECEIVED_TARGET_ABORT = 1 << 12;
138         /// A master device transaction was terminated with master-abort.
139         const RECEIVED_MASTER_ABORT = 1 << 13;
140         /// A device asserts SERR#.
141         const SIGNALED_SYSTEM_ERROR = 1 << 14;
142         /// The device detects a parity error, even if parity error handling is disabled.
143         const DETECTED_PARITY_ERROR = 1 << 15;
144     }
145 }
146 
147 bitflags! {
148     /// The command register in PCI configuration space.
149     pub struct Command: u16 {
150         /// The device can respond to I/O Space accesses.
151         const IO_SPACE = 1 << 0;
152         /// The device can respond to Memory Space accesses.
153         const MEMORY_SPACE = 1 << 1;
154         /// The device can behave as a bus master.
155         const BUS_MASTER = 1 << 2;
156         /// The device can monitor Special Cycle operations.
157         const SPECIAL_CYCLES = 1 << 3;
158         /// The device can generate the Memory Write and Invalidate command.
159         const MEMORY_WRITE_AND_INVALIDATE_ENABLE = 1 << 4;
160         /// The device will snoop palette register data.
161         const VGA_PALETTE_SNOOP = 1 << 5;
162         /// The device should take its normal action when a parity error is detected.
163         const PARITY_ERROR_RESPONSE = 1 << 6;
164         // Bit 7 is reserved.
165         /// The SERR# driver is enabled.
166         const SERR_ENABLE = 1 << 8;
167         /// The device is allowed to generate fast back-to-back transactions.
168         const FAST_BACK_TO_BACK_ENABLE = 1 << 9;
169         /// Assertion of the device's INTx# signal is disabled.
170         const INTERRUPT_DISABLE = 1 << 10;
171     }
172 }
173 
174 /// The type of a PCI device function header.
175 /// 标头类型/设备类型
176 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
177 pub enum HeaderType {
178     /// A normal PCI device.
179     Standard,
180     /// A PCI to PCI bridge.
181     PciPciBridge,
182     /// A PCI to CardBus bridge.
183     PciCardbusBridge,
184     /// Unrecognised header type.
185     Unrecognised(u8),
186 }
187 /// u8到HeaderType的转换
188 impl From<u8> for HeaderType {
189     fn from(value: u8) -> Self {
190         match value {
191             0x00 => Self::Standard,
192             0x01 => Self::PciPciBridge,
193             0x02 => Self::PciCardbusBridge,
194             _ => Self::Unrecognised(value),
195         }
196     }
197 }
198 /// Pci可能触发的各种错误
199 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
200 pub enum PciError {
201     /// The device reported an invalid BAR type.
202     InvalidBarType,
203     CreateMmioError,
204     InvalidBusDeviceFunction,
205     SegmentNotFound,
206     GetWrongHeader,
207     UnrecognisedHeaderType,
208     PciDeviceStructureTransformError,
209 }
210 ///实现PciError的Display trait,使其可以直接输出
211 impl Display for PciError {
212     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
213         match self {
214             Self::InvalidBarType => write!(f, "Invalid PCI BAR type."),
215             Self::CreateMmioError => write!(f, "Error occurred while creating mmio."),
216             Self::InvalidBusDeviceFunction => write!(f, "Found invalid BusDeviceFunction."),
217             Self::SegmentNotFound => write!(f, "Target segment not found"),
218             Self::GetWrongHeader => write!(f, "GetWrongHeader with vendor id 0xffff"),
219             Self::UnrecognisedHeaderType => write!(f, "Found device with unrecognised header type"),
220             Self::PciDeviceStructureTransformError => {
221                 write!(f, "Found None When transform Pci device structure")
222             }
223         }
224     }
225 }
226 
227 /// trait类型Pci_Device_Structure表示pci设备,动态绑定三种具体设备类型:Pci_Device_Structure_General_Device、Pci_Device_Structure_Pci_to_Pci_Bridge、Pci_Device_Structure_Pci_to_Cardbus_Bridge
228 pub trait PciDeviceStructure: Send + Sync {
229     /// @brief 获取设备类型
230     /// @return HeaderType 设备类型
231     fn header_type(&self) -> HeaderType;
232     /// @brief 当其为standard设备时返回&Pci_Device_Structure_General_Device,其余情况返回None
233     fn as_standard_device(&self) -> Option<&PciDeviceStructureGeneralDevice> {
234         None
235     }
236     /// @brief 当其为pci to pci bridge设备时返回&Pci_Device_Structure_Pci_to_Pci_Bridge,其余情况返回None
237     fn as_pci_to_pci_bridge_device(&self) -> Option<&PciDeviceStructurePciToPciBridge> {
238         None
239     }
240     /// @brief 当其为pci to cardbus bridge设备时返回&Pci_Device_Structure_Pci_to_Cardbus_Bridge,其余情况返回None
241     fn as_pci_to_carbus_bridge_device(&self) -> Option<&PciDeviceStructurePciToCardbusBridge> {
242         None
243     }
244     /// @brief 获取Pci设备共有的common_header
245     /// @return 返回其不可变引用
246     fn common_header(&self) -> &PciDeviceStructureHeader;
247     /// @brief 当其为standard设备时返回&mut Pci_Device_Structure_General_Device,其余情况返回None
248     fn as_standard_device_mut(&mut self) -> Option<&mut PciDeviceStructureGeneralDevice> {
249         None
250     }
251     /// @brief 当其为pci to pci bridge设备时返回&mut Pci_Device_Structure_Pci_to_Pci_Bridge,其余情况返回None
252     fn as_pci_to_pci_bridge_device_mut(&mut self) -> Option<&mut PciDeviceStructurePciToPciBridge> {
253         None
254     }
255     /// @brief 当其为pci to cardbus bridge设备时返回&mut Pci_Device_Structure_Pci_to_Cardbus_Bridge,其余情况返回None
256     fn as_pci_to_carbus_bridge_device_mut(
257         &mut self,
258     ) -> Option<&mut PciDeviceStructurePciToCardbusBridge> {
259         None
260     }
261     /// @brief 返回迭代器,遍历capabilities
262     fn capabilities(&self) -> Option<CapabilityIterator> {
263         None
264     }
265     /// @brief 获取Status、Command寄存器的值
266     fn status_command(&self) -> (Status, Command) {
267         let common_header = self.common_header();
268         let status = Status::from_bits_truncate(common_header.status);
269         let command = Command::from_bits_truncate(common_header.command);
270         (status, command)
271     }
272     /// @brief 设置Command寄存器的值
273     fn set_command(&mut self, command: Command) {
274         let common_header = self.common_header_mut();
275         let command = command.bits();
276         common_header.command = command;
277         PciArch::write_config(
278             &common_header.bus_device_function,
279             STATUS_COMMAND_OFFSET,
280             command as u32,
281         );
282     }
283     /// @brief 获取Pci设备共有的common_header
284     /// @return 返回其可变引用
285     fn common_header_mut(&mut self) -> &mut PciDeviceStructureHeader;
286     /// @brief 读取standard设备的bar寄存器,映射后将结果加入结构体的standard_device_bar变量
287     /// @return 只有standard设备才返回成功或者错误,其余返回None
288     fn bar_init(&mut self) -> Option<Result<u8, PciError>> {
289         None
290     }
291     /// todo
292     fn msix_init(&mut self) -> Option<Result<u8, PciError>> {
293         None
294     }
295     fn enable_master(&mut self) {
296         self.set_command(Command::IO_SPACE | Command::MEMORY_SPACE | Command::BUS_MASTER);
297     }
298 }
299 
300 /// Pci_Device_Structure_Header PCI设备结构体共有的头部
301 #[derive(Clone, Debug)]
302 pub struct PciDeviceStructureHeader {
303     // 包含msix table地址的bar的mmio基地址 todo:以下四个作为一个结构体统一管理
304     pub msix_mmio_vaddr: u64,
305     pub msix_mmio_size: u64,  // msix映射长度
306     pub msix_offset: u32,     // msix表的offset
307     pub msix_table_size: u16, // msix表的表项数量
308     // ==== busdevicefunction变量表示该结构体所处的位置
309     pub bus_device_function: BusDeviceFunction,
310     pub vendor_id: u16, // 供应商ID 0xffff是一个无效值,在读取访问不存在的设备的配置空间寄存器时返回
311     pub device_id: u16, // 设备ID,标志特定设备
312     pub command: u16, // 提供对设备生成和响应pci周期的能力的控制 向该寄存器写入0时,设备与pci总线断开除配置空间访问以外的所有连接
313     pub status: u16,  // 用于记录pci总线相关时间的状态信息寄存器
314     pub revision_id: u8, // 修订ID,指定特定设备的修订标志符
315     pub prog_if: u8, // 编程接口字节,一个只读寄存器,指定设备具有的寄存器级别的编程接口(如果有的话)
316     pub subclass: u8, // 子类。指定设备执行的特定功能的只读寄存器
317     pub class_code: u8, // 类代码,一个只读寄存器,指定设备执行的功能类型
318     pub cache_line_size: u8, // 缓存线大小:以 32 位为单位指定系统缓存线大小。设备可以限制它可以支持的缓存线大小的数量,如果不支持的值写入该字段,设备将表现得好像写入了 0 值
319     pub latency_timer: u8,   // 延迟计时器:以 PCI 总线时钟为单位指定延迟计时器。
320     pub header_type: u8, // 标头类型 a value of 0x0 specifies a general device, a value of 0x1 specifies a PCI-to-PCI bridge, and a value of 0x2 specifies a CardBus bridge. If bit 7 of this register is set, the device has multiple functions; otherwise, it is a single function device.
321     pub bist: u8, // Represents that status and allows control of a devices BIST (built-in self test).
322                   // Here is the layout of the BIST register:
323                   // |     bit7     |    bit6    | Bits 5-4 |     Bits 3-0    |
324                   // | BIST Capable | Start BIST | Reserved | Completion Code |
325                   // for more details, please visit https://wiki.osdev.org/PCI
326 }
327 
328 /// Pci_Device_Structure_General_Device PCI标准设备结构体
329 #[derive(Clone, Debug)]
330 pub struct PciDeviceStructureGeneralDevice {
331     pub common_header: PciDeviceStructureHeader,
332     pub standard_device_bar: PciStandardDeviceBar,
333     pub cardbus_cis_pointer: u32, // 指向卡信息结构,供在 CardBus 和 PCI 之间共享芯片的设备使用。
334     pub subsystem_vendor_id: u16,
335     pub subsystem_id: u16,
336     pub expansion_rom_base_address: u32,
337     pub capabilities_pointer: u8,
338     pub reserved0: u8,
339     pub reserved1: u16,
340     pub reserved2: u32,
341     pub interrupt_line: u8, // 指定设备的中断引脚连接到系统中断控制器的哪个输入,并由任何使用中断引脚的设备实现。对于 x86 架构,此寄存器对应于 PIC IRQ 编号 0-15(而不是 I/O APIC IRQ 编号),并且值0xFF定义为无连接。
342     pub interrupt_pin: u8, // 指定设备使用的中断引脚。其中值为0x1INTA#、0x2INTB#、0x3INTC#、0x4INTD#,0x0表示设备不使用中断引脚。
343     pub min_grant: u8, // 一个只读寄存器,用于指定设备所需的突发周期长度(以 1/4 微秒为单位)(假设时钟速率为 33 MHz)
344     pub max_latency: u8, // 一个只读寄存器,指定设备需要多长时间访问一次 PCI 总线(以 1/4 微秒为单位)。
345 }
346 impl PciDeviceStructure for PciDeviceStructureGeneralDevice {
347     fn header_type(&self) -> HeaderType {
348         HeaderType::Standard
349     }
350     fn as_standard_device(&self) -> Option<&PciDeviceStructureGeneralDevice> {
351         Some(self)
352     }
353     fn as_standard_device_mut(&mut self) -> Option<&mut PciDeviceStructureGeneralDevice> {
354         Some(self)
355     }
356     fn common_header(&self) -> &PciDeviceStructureHeader {
357         &self.common_header
358     }
359 
360     fn common_header_mut(&mut self) -> &mut PciDeviceStructureHeader {
361         &mut self.common_header
362     }
363     fn capabilities(&self) -> Option<CapabilityIterator> {
364         Some(CapabilityIterator {
365             bus_device_function: self.common_header.bus_device_function,
366             next_capability_offset: Some(self.capabilities_pointer),
367         })
368     }
369     fn bar_init(&mut self) -> Option<Result<u8, PciError>> {
370         let common_header = &self.common_header;
371         match pci_bar_init(common_header.bus_device_function) {
372             Ok(bar) => {
373                 self.standard_device_bar = bar;
374                 Some(Ok(0))
375             }
376             Err(e) => Some(Err(e)),
377         }
378     }
379 }
380 /// Pci_Device_Structure_Pci_to_Pci_Bridge pci-to-pci桥设备结构体
381 #[derive(Clone, Debug)]
382 pub struct PciDeviceStructurePciToPciBridge {
383     pub common_header: PciDeviceStructureHeader,
384     pub bar0: u32,
385     pub bar1: u32,
386     pub primary_bus_number: u8,
387     pub secondary_bus_number: u8,
388     pub subordinate_bus_number: u8,
389     pub secondary_latency_timer: u8,
390     pub io_base: u8,
391     pub io_limit: u8,
392     pub secondary_status: u16,
393     pub memory_base: u16,
394     pub memory_limit: u16,
395     pub prefetchable_memory_base: u16,
396     pub prefetchable_memory_limit: u16,
397     pub prefetchable_base_upper_32_bits: u32,
398     pub prefetchable_limit_upper_32_bits: u32,
399     pub io_base_upper_16_bits: u16,
400     pub io_limit_upper_16_bits: u16,
401     pub capability_pointer: u8,
402     pub reserved0: u8,
403     pub reserved1: u16,
404     pub expansion_rom_base_address: u32,
405     pub interrupt_line: u8,
406     pub interrupt_pin: u8,
407     pub bridge_control: u16,
408 }
409 impl PciDeviceStructure for PciDeviceStructurePciToPciBridge {
410     fn header_type(&self) -> HeaderType {
411         HeaderType::PciPciBridge
412     }
413     fn as_pci_to_pci_bridge_device(&self) -> Option<&PciDeviceStructurePciToPciBridge> {
414         Some(self)
415     }
416     fn as_pci_to_pci_bridge_device_mut(&mut self) -> Option<&mut PciDeviceStructurePciToPciBridge> {
417         Some(self)
418     }
419     fn common_header(&self) -> &PciDeviceStructureHeader {
420         &self.common_header
421     }
422 
423     fn common_header_mut(&mut self) -> &mut PciDeviceStructureHeader {
424         &mut self.common_header
425     }
426 }
427 /// Pci_Device_Structure_Pci_to_Cardbus_Bridge Pci_to_Cardbus桥设备结构体
428 #[derive(Clone, Debug)]
429 pub struct PciDeviceStructurePciToCardbusBridge {
430     pub common_header: PciDeviceStructureHeader,
431     pub cardbus_socket_ex_ca_base_address: u32,
432     pub offset_of_capabilities_list: u8,
433     pub reserved: u8,
434     pub secondary_status: u16,
435     pub pci_bus_number: u8,
436     pub card_bus_bus_number: u8,
437     pub subordinate_bus_number: u8,
438     pub card_bus_latency_timer: u8,
439     pub memory_base_address0: u32,
440     pub memory_limit0: u32,
441     pub memory_base_address1: u32,
442     pub memory_limit1: u32,
443     pub io_base_address0: u32,
444     pub io_limit0: u32,
445     pub io_base_address1: u32,
446     pub io_limit1: u32,
447     pub interrupt_line: u8,
448     pub interrupt_pin: u8,
449     pub bridge_control: u16,
450     pub subsystem_device_id: u16,
451     pub subsystem_vendor_id: u16,
452     pub pc_card_legacy_mode_base_address_16_bit: u32,
453 }
454 impl PciDeviceStructure for PciDeviceStructurePciToCardbusBridge {
455     fn header_type(&self) -> HeaderType {
456         HeaderType::PciCardbusBridge
457     }
458     fn as_pci_to_carbus_bridge_device(&self) -> Option<&PciDeviceStructurePciToCardbusBridge> {
459         Some(&self)
460     }
461     fn as_pci_to_carbus_bridge_device_mut(
462         &mut self,
463     ) -> Option<&mut PciDeviceStructurePciToCardbusBridge> {
464         Some(self)
465     }
466     fn common_header(&self) -> &PciDeviceStructureHeader {
467         &self.common_header
468     }
469 
470     fn common_header_mut(&mut self) -> &mut PciDeviceStructureHeader {
471         &mut self.common_header
472     }
473 }
474 
475 /// 代表一个PCI segement greoup.
476 #[derive(Copy, Clone, Debug, PartialEq)]
477 pub struct PciRoot {
478     pub physical_address_base: u64,                //物理地址,acpi获取
479     pub mmio_base: Option<*mut u32>,               //映射后的虚拟地址,为方便访问数据这里转化成指针
480     pub segement_group_number: SegmentGroupNumber, //segement greoup的id
481     pub bus_begin: u8,                             //该分组中的最小bus
482     pub bus_end: u8,                               //该分组中的最大bus
483 }
484 ///线程间共享需要,该结构体只需要在初始化时写入数据,无需读写锁保证线程安全
485 unsafe impl Send for PciRoot {}
486 unsafe impl Sync for PciRoot {}
487 ///实现PciRoot的Display trait,自定义输出
488 impl Display for PciRoot {
489     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
490         write!(
491                 f,
492                 "PCI Root with segement:{}, bus begin at {}, bus end at {}, physical address at {},mapped at {:#x}",
493                 self.segement_group_number, self.bus_begin, self.bus_end, self.physical_address_base, self.mmio_base.unwrap() as usize
494             )
495     }
496 }
497 
498 impl PciRoot {
499     /// @brief 初始化结构体,获取ecam root所在物理地址后map到虚拟地址,再将该虚拟地址加入mmio_base变量
500     /// @return 成功返回结果,错误返回错误类型
501     pub fn new(segment_group_number: SegmentGroupNumber) -> Result<Self, PciError> {
502         let mut pci_root = PciArch::ecam_root(segment_group_number)?;
503         pci_root.map()?;
504         Ok(pci_root)
505     }
506     /// @brief  完成物理地址到虚拟地址的映射,并将虚拟地址加入mmio_base变量
507     /// @return 返回错误或Ok(0)
508     fn map(&mut self) -> Result<u8, PciError> {
509         let bus_number = self.bus_end - self.bus_begin + 1;
510         let bus_number_double = (bus_number + 1) / 2;
511         let mut virtaddress: u64 = 0;
512         let vaddr_ptr = &mut virtaddress as *mut u64;
513         let mut virtsize: u64 = 0;
514         let virtsize_ptr = &mut virtsize as *mut u64;
515         let size = bus_number_double as u32 * PAGE_2M_SIZE;
516         unsafe {
517             let initial_mm_ptr = &mut initial_mm as *mut mm_struct;
518             if let Err(_) =
519                 MMIO_POOL.create_mmio(size, (VM_IO | VM_DONTCOPY) as u64, vaddr_ptr, virtsize_ptr)
520             {
521                 kerror!("Create mmio failed when initing ecam");
522                 return Err(PciError::CreateMmioError);
523             };
524             //kdebug!("virtaddress={:#x},virtsize={:#x}",virtaddress,virtsize);
525             mm_map(
526                 initial_mm_ptr,
527                 virtaddress,
528                 size as u64,
529                 self.physical_address_base,
530             );
531         }
532         self.mmio_base = Some(virtaddress as *mut u32);
533         Ok(0)
534     }
535     /// @brief 获得要操作的寄存器相对于mmio_offset的偏移量
536     /// @param bus_device_function 在同一个group中pci设备的唯一标识符
537     /// @param register_offset 寄存器在设备中的offset
538     /// @return u32 要操作的寄存器相对于mmio_offset的偏移量
539     fn cam_offset(&self, bus_device_function: BusDeviceFunction, register_offset: u16) -> u32 {
540         assert!(bus_device_function.valid());
541         let bdf = ((bus_device_function.bus - self.bus_begin) as u32) << 8
542             | (bus_device_function.device as u32) << 3
543             | bus_device_function.function as u32;
544         let address = bdf << 12 | register_offset as u32;
545         // Ensure that address is word-aligned.
546         assert!(address & 0x3 == 0);
547         address
548     }
549     /// @brief 通过bus_device_function和offset读取相应位置寄存器的值(32位)
550     /// @param bus_device_function 在同一个group中pci设备的唯一标识符
551     /// @param register_offset 寄存器在设备中的offset
552     /// @return u32 寄存器读值结果
553     pub fn read_config(&self, bus_device_function: BusDeviceFunction, register_offset: u16) -> u32 {
554         let address = self.cam_offset(bus_device_function, register_offset);
555         unsafe {
556             // Right shift to convert from byte offset to word offset.
557             (self.mmio_base.unwrap().add((address >> 2) as usize)).read_volatile()
558         }
559     }
560 
561     /// @brief 通过bus_device_function和offset写入相应位置寄存器值(32位)
562     /// @param bus_device_function 在同一个group中pci设备的唯一标识符
563     /// @param register_offset 寄存器在设备中的offset
564     /// @param data 要写入的值
565     pub fn write_config(
566         &mut self,
567         bus_device_function: BusDeviceFunction,
568         register_offset: u16,
569         data: u32,
570     ) {
571         let address = self.cam_offset(bus_device_function, register_offset);
572         // Safe because both the `mmio_base` and the address offset are properly aligned, and the
573         // resulting pointer is within the MMIO range of the CAM.
574         unsafe {
575             // Right shift to convert from byte offset to word offset.
576             (self.mmio_base.unwrap().add((address >> 2) as usize)).write_volatile(data)
577         }
578     }
579     /// @brief 返回迭代器,遍历pcie设备的external_capabilities
580     pub fn external_capabilities(
581         &self,
582         bus_device_function: BusDeviceFunction,
583     ) -> ExternalCapabilityIterator {
584         ExternalCapabilityIterator {
585             root: self,
586             bus_device_function,
587             next_capability_offset: Some(0x100),
588         }
589     }
590 }
591 /// Gets the capabilities 'pointer' for the device function, if any.
592 /// @brief 获取第一个capability 的offset
593 /// @param bus_device_function PCI设备的唯一标识
594 /// @return Option<u8> offset
595 pub fn capabilities_offset(bus_device_function: BusDeviceFunction) -> Option<u8> {
596     let result = PciArch::read_config(&bus_device_function, STATUS_COMMAND_OFFSET);
597     let status: Status = Status::from_bits_truncate((result >> 16) as u16);
598     if status.contains(Status::CAPABILITIES_LIST) {
599         let cap_pointer = PciArch::read_config(&bus_device_function, 0x34) as u8 & 0xFC;
600         Some(cap_pointer)
601     } else {
602         None
603     }
604 }
605 
606 /// @brief 读取pci设备头部
607 /// @param bus_device_function PCI设备的唯一标识
608 /// @param add_to_list 是否添加到链表
609 /// @return 返回的header(trait 类型)
610 fn pci_read_header(
611     bus_device_function: BusDeviceFunction,
612     add_to_list: bool,
613 ) -> Result<Box<dyn PciDeviceStructure>, PciError> {
614     // 先读取公共header
615     let result = PciArch::read_config(&bus_device_function, 0x00);
616     let vendor_id = result as u16;
617     let device_id = (result >> 16) as u16;
618 
619     let result = PciArch::read_config(&bus_device_function, 0x04);
620     let command = result as u16;
621     let status = (result >> 16) as u16;
622 
623     let result = PciArch::read_config(&bus_device_function, 0x08);
624     let revision_id = result as u8;
625     let prog_if = (result >> 8) as u8;
626     let subclass = (result >> 16) as u8;
627     let class_code = (result >> 24) as u8;
628 
629     let result = PciArch::read_config(&bus_device_function, 0x0c);
630     let cache_line_size = result as u8;
631     let latency_timer = (result >> 8) as u8;
632     let header_type = (result >> 16) as u8;
633     let bist = (result >> 24) as u8;
634     if vendor_id == 0xffff {
635         return Err(PciError::GetWrongHeader);
636     }
637     let header = PciDeviceStructureHeader {
638         msix_mmio_vaddr: 0,
639         msix_mmio_size: 0,
640         msix_offset: 0,
641         msix_table_size: 0,
642         bus_device_function,
643         vendor_id,
644         device_id,
645         command,
646         status,
647         revision_id,
648         prog_if,
649         subclass,
650         class_code,
651         cache_line_size,
652         latency_timer,
653         header_type,
654         bist,
655     };
656     match HeaderType::from(header_type & 0x7f) {
657         HeaderType::Standard => {
658             let general_device = pci_read_general_device_header(header, &bus_device_function);
659             let box_general_device = Box::new(general_device);
660             let box_general_device_clone = box_general_device.clone();
661             if add_to_list {
662                 PCI_DEVICE_LINKEDLIST.add(box_general_device);
663             }
664             Ok(box_general_device_clone)
665         }
666         HeaderType::PciPciBridge => {
667             let pci_to_pci_bridge = pci_read_pci_to_pci_bridge_header(header, &bus_device_function);
668             let box_pci_to_pci_bridge = Box::new(pci_to_pci_bridge);
669             let box_pci_to_pci_bridge_clone = box_pci_to_pci_bridge.clone();
670             if add_to_list {
671                 PCI_DEVICE_LINKEDLIST.add(box_pci_to_pci_bridge);
672             }
673             Ok(box_pci_to_pci_bridge_clone)
674         }
675         HeaderType::PciCardbusBridge => {
676             let pci_cardbus_bridge =
677                 pci_read_pci_to_cardbus_bridge_header(header, &bus_device_function);
678             let box_pci_cardbus_bridge = Box::new(pci_cardbus_bridge);
679             let box_pci_cardbus_bridge_clone = box_pci_cardbus_bridge.clone();
680             if add_to_list {
681                 PCI_DEVICE_LINKEDLIST.add(box_pci_cardbus_bridge);
682             }
683             Ok(box_pci_cardbus_bridge_clone)
684         }
685         HeaderType::Unrecognised(_) => Err(PciError::UnrecognisedHeaderType),
686     }
687 }
688 
689 /// @brief 读取type为0x0的pci设备的header
690 /// 本函数只应被 pci_read_header()调用
691 /// @param common_header 共有头部
692 /// @param bus_device_function PCI设备的唯一标识
693 /// @return Pci_Device_Structure_General_Device 标准设备头部
694 fn pci_read_general_device_header(
695     common_header: PciDeviceStructureHeader,
696     bus_device_function: &BusDeviceFunction,
697 ) -> PciDeviceStructureGeneralDevice {
698     let standard_device_bar = PciStandardDeviceBar::default();
699     let cardbus_cis_pointer = PciArch::read_config(bus_device_function, 0x28);
700 
701     let result = PciArch::read_config(bus_device_function, 0x2c);
702     let subsystem_vendor_id = result as u16;
703     let subsystem_id = (result >> 16) as u16;
704 
705     let expansion_rom_base_address = PciArch::read_config(bus_device_function, 0x30);
706 
707     let result = PciArch::read_config(bus_device_function, 0x34);
708     let capabilities_pointer = result as u8;
709     let reserved0 = (result >> 8) as u8;
710     let reserved1 = (result >> 16) as u16;
711 
712     let reserved2 = PciArch::read_config(bus_device_function, 0x38);
713 
714     let result = PciArch::read_config(bus_device_function, 0x3c);
715     let interrupt_line = result as u8;
716     let interrupt_pin = (result >> 8) as u8;
717     let min_grant = (result >> 16) as u8;
718     let max_latency = (result >> 24) as u8;
719     PciDeviceStructureGeneralDevice {
720         common_header,
721         standard_device_bar,
722         cardbus_cis_pointer,
723         subsystem_vendor_id,
724         subsystem_id,
725         expansion_rom_base_address,
726         capabilities_pointer,
727         reserved0,
728         reserved1,
729         reserved2,
730         interrupt_line,
731         interrupt_pin,
732         min_grant,
733         max_latency,
734     }
735 }
736 
737 /// @brief 读取type为0x1的pci设备的header
738 /// 本函数只应被 pci_read_header()调用
739 /// @param common_header 共有头部
740 /// @param bus_device_function PCI设备的唯一标识
741 /// @return Pci_Device_Structure_Pci_to_Pci_Bridge pci-to-pci 桥设备头部
742 fn pci_read_pci_to_pci_bridge_header(
743     common_header: PciDeviceStructureHeader,
744     bus_device_function: &BusDeviceFunction,
745 ) -> PciDeviceStructurePciToPciBridge {
746     let bar0 = PciArch::read_config(bus_device_function, 0x10);
747     let bar1 = PciArch::read_config(bus_device_function, 0x14);
748 
749     let result = PciArch::read_config(bus_device_function, 0x18);
750 
751     let primary_bus_number = result as u8;
752     let secondary_bus_number = (result >> 8) as u8;
753     let subordinate_bus_number = (result >> 16) as u8;
754     let secondary_latency_timer = (result >> 24) as u8;
755 
756     let result = PciArch::read_config(bus_device_function, 0x1c);
757     let io_base = result as u8;
758     let io_limit = (result >> 8) as u8;
759     let secondary_status = (result >> 16) as u16;
760 
761     let result = PciArch::read_config(bus_device_function, 0x20);
762     let memory_base = result as u16;
763     let memory_limit = (result >> 16) as u16;
764 
765     let result = PciArch::read_config(bus_device_function, 0x24);
766     let prefetchable_memory_base = result as u16;
767     let prefetchable_memory_limit = (result >> 16) as u16;
768 
769     let prefetchable_base_upper_32_bits = PciArch::read_config(bus_device_function, 0x28);
770     let prefetchable_limit_upper_32_bits = PciArch::read_config(bus_device_function, 0x2c);
771 
772     let result = PciArch::read_config(bus_device_function, 0x30);
773     let io_base_upper_16_bits = result as u16;
774     let io_limit_upper_16_bits = (result >> 16) as u16;
775 
776     let result = PciArch::read_config(bus_device_function, 0x34);
777     let capability_pointer = result as u8;
778     let reserved0 = (result >> 8) as u8;
779     let reserved1 = (result >> 16) as u16;
780 
781     let expansion_rom_base_address = PciArch::read_config(bus_device_function, 0x38);
782 
783     let result = PciArch::read_config(bus_device_function, 0x3c);
784     let interrupt_line = result as u8;
785     let interrupt_pin = (result >> 8) as u8;
786     let bridge_control = (result >> 16) as u16;
787     PciDeviceStructurePciToPciBridge {
788         common_header,
789         bar0,
790         bar1,
791         primary_bus_number,
792         secondary_bus_number,
793         subordinate_bus_number,
794         secondary_latency_timer,
795         io_base,
796         io_limit,
797         secondary_status,
798         memory_base,
799         memory_limit,
800         prefetchable_memory_base,
801         prefetchable_memory_limit,
802         prefetchable_base_upper_32_bits,
803         prefetchable_limit_upper_32_bits,
804         io_base_upper_16_bits,
805         io_limit_upper_16_bits,
806         capability_pointer,
807         reserved0,
808         reserved1,
809         expansion_rom_base_address,
810         interrupt_line,
811         interrupt_pin,
812         bridge_control,
813     }
814 }
815 
816 /// @brief 读取type为0x2的pci设备的header
817 /// 本函数只应被 pci_read_header()调用
818 /// @param common_header 共有头部
819 /// @param bus_device_function PCI设备的唯一标识
820 /// @return ) -> Pci_Device_Structure_Pci_to_Cardbus_Bridge  pci-to-cardbus 桥设备头部
821 fn pci_read_pci_to_cardbus_bridge_header(
822     common_header: PciDeviceStructureHeader,
823     busdevicefunction: &BusDeviceFunction,
824 ) -> PciDeviceStructurePciToCardbusBridge {
825     let cardbus_socket_ex_ca_base_address = PciArch::read_config(busdevicefunction, 0x10);
826 
827     let result = PciArch::read_config(busdevicefunction, 0x14);
828     let offset_of_capabilities_list = result as u8;
829     let reserved = (result >> 8) as u8;
830     let secondary_status = (result >> 16) as u16;
831 
832     let result = PciArch::read_config(busdevicefunction, 0x18);
833     let pci_bus_number = result as u8;
834     let card_bus_bus_number = (result >> 8) as u8;
835     let subordinate_bus_number = (result >> 16) as u8;
836     let card_bus_latency_timer = (result >> 24) as u8;
837 
838     let memory_base_address0 = PciArch::read_config(busdevicefunction, 0x1c);
839     let memory_limit0 = PciArch::read_config(busdevicefunction, 0x20);
840     let memory_base_address1 = PciArch::read_config(busdevicefunction, 0x24);
841     let memory_limit1 = PciArch::read_config(busdevicefunction, 0x28);
842 
843     let io_base_address0 = PciArch::read_config(busdevicefunction, 0x2c);
844     let io_limit0 = PciArch::read_config(busdevicefunction, 0x30);
845     let io_base_address1 = PciArch::read_config(busdevicefunction, 0x34);
846     let io_limit1 = PciArch::read_config(busdevicefunction, 0x38);
847     let result = PciArch::read_config(busdevicefunction, 0x3c);
848     let interrupt_line = result as u8;
849     let interrupt_pin = (result >> 8) as u8;
850     let bridge_control = (result >> 16) as u16;
851 
852     let result = PciArch::read_config(busdevicefunction, 0x40);
853     let subsystem_device_id = result as u16;
854     let subsystem_vendor_id = (result >> 16) as u16;
855 
856     let pc_card_legacy_mode_base_address_16_bit = PciArch::read_config(busdevicefunction, 0x44);
857     PciDeviceStructurePciToCardbusBridge {
858         common_header,
859         cardbus_socket_ex_ca_base_address,
860         offset_of_capabilities_list,
861         reserved,
862         secondary_status,
863         pci_bus_number,
864         card_bus_bus_number,
865         subordinate_bus_number,
866         card_bus_latency_timer,
867         memory_base_address0,
868         memory_limit0,
869         memory_base_address1,
870         memory_limit1,
871         io_base_address0,
872         io_limit0,
873         io_base_address1,
874         io_limit1,
875         interrupt_line,
876         interrupt_pin,
877         bridge_control,
878         subsystem_device_id,
879         subsystem_vendor_id,
880         pc_card_legacy_mode_base_address_16_bit,
881     }
882 }
883 
884 /// @brief 检查所有bus上的设备并将其加入链表
885 /// @return 成功返回ok(),失败返回失败原因
886 fn pci_check_all_buses() -> Result<u8, PciError> {
887     kinfo!("Checking all devices in PCI bus...");
888     let busdevicefunction = BusDeviceFunction {
889         bus: 0,
890         device: 0,
891         function: 0,
892     };
893     let header = pci_read_header(busdevicefunction, false)?;
894     let common_header = header.common_header();
895     pci_check_bus(0)?;
896     if common_header.header_type & 0x80 != 0 {
897         for function in 1..8 {
898             pci_check_bus(function)?;
899         }
900     }
901     Ok(0)
902 }
903 /// @brief 检查特定设备并将其加入链表
904 /// @return 成功返回ok(),失败返回失败原因
905 fn pci_check_function(busdevicefunction: BusDeviceFunction) -> Result<u8, PciError> {
906     //kdebug!("PCI check function {}", busdevicefunction.function);
907     let header = match pci_read_header(busdevicefunction, true) {
908         Ok(header) => header,
909         Err(PciError::GetWrongHeader) => {
910             return Ok(255);
911         }
912         Err(e) => {
913             return Err(e);
914         }
915     };
916     let common_header = header.common_header();
917     if (common_header.class_code == 0x06)
918         && (common_header.subclass == 0x04 || common_header.subclass == 0x09)
919     {
920         let pci_to_pci_bridge = header
921             .as_pci_to_pci_bridge_device()
922             .ok_or(PciError::PciDeviceStructureTransformError)?;
923         let secondary_bus = pci_to_pci_bridge.secondary_bus_number;
924         pci_check_bus(secondary_bus)?;
925     }
926     Ok(0)
927 }
928 
929 /// @brief 检查device上的设备并将其加入链表
930 /// @return 成功返回ok(),失败返回失败原因
931 fn pci_check_device(bus: u8, device: u8) -> Result<u8, PciError> {
932     //kdebug!("PCI check device {}", device);
933     let busdevicefunction = BusDeviceFunction {
934         bus,
935         device,
936         function: 0,
937     };
938     let header = match pci_read_header(busdevicefunction, false) {
939         Ok(header) => header,
940         Err(PciError::GetWrongHeader) => {
941             //设备不存在,直接返回即可,不用终止遍历
942             return Ok(255);
943         }
944         Err(e) => {
945             return Err(e);
946         }
947     };
948     pci_check_function(busdevicefunction)?;
949     let common_header = header.common_header();
950     if common_header.header_type & 0x80 != 0 {
951         kdebug!(
952             "Detected multi func device in bus{},device{}",
953             busdevicefunction.bus,
954             busdevicefunction.device
955         );
956         // 这是一个多function的设备,因此查询剩余的function
957         for function in 1..8 {
958             let busdevicefunction = BusDeviceFunction {
959                 bus,
960                 device,
961                 function,
962             };
963             pci_check_function(busdevicefunction)?;
964         }
965     }
966     Ok(0)
967 }
968 /// @brief 检查该bus上的设备并将其加入链表
969 /// @return 成功返回ok(),失败返回失败原因
970 fn pci_check_bus(bus: u8) -> Result<u8, PciError> {
971     //kdebug!("PCI check bus {}", bus);
972     for device in 0..32 {
973         pci_check_device(bus, device)?;
974     }
975     Ok(0)
976 }
977 /// @brief pci初始化函数(for c)
978 #[no_mangle]
979 pub extern "C" fn rs_pci_init() {
980     pci_init();
981     //kdebug!("{}",PCI_ROOT_0.unwrap());
982 }
983 /// @brief pci初始化函数
984 pub fn pci_init() {
985     kinfo!("Initializing PCI bus...");
986     if let Err(e) = pci_check_all_buses() {
987         kerror!("pci init failed when checking bus because of error: {}", e);
988         return;
989     }
990     kinfo!(
991         "Total pci device and function num = {}",
992         PCI_DEVICE_LINKEDLIST.num()
993     );
994     let list = PCI_DEVICE_LINKEDLIST.read();
995     for box_pci_device in list.iter() {
996         let common_header = box_pci_device.common_header();
997         match box_pci_device.header_type() {
998             HeaderType::Standard if common_header.status & 0x10 != 0 => {
999                 kinfo!("Found pci standard device with class code ={} subclass={} status={:#x} cap_pointer={:#x}  vendor={:#x}, device id={:#x}", common_header.class_code, common_header.subclass, common_header.status, box_pci_device.as_standard_device().unwrap().capabilities_pointer,common_header.vendor_id, common_header.device_id);
1000             }
1001             HeaderType::Standard => {
1002                 kinfo!(
1003                     "Found pci standard device with class code ={} subclass={} status={:#x} ",
1004                     common_header.class_code,
1005                     common_header.subclass,
1006                     common_header.status
1007                 );
1008             }
1009             HeaderType::PciPciBridge if common_header.status & 0x10 != 0 => {
1010                 kinfo!("Found pci-to-pci bridge device with class code ={} subclass={} status={:#x} cap_pointer={:#x}", common_header.class_code, common_header.subclass, common_header.status, box_pci_device.as_standard_device().unwrap().capabilities_pointer);
1011             }
1012             HeaderType::PciPciBridge => {
1013                 kinfo!(
1014                     "Found pci-to-pci bridge device with class code ={} subclass={} status={:#x} ",
1015                     common_header.class_code,
1016                     common_header.subclass,
1017                     common_header.status
1018                 );
1019             }
1020             HeaderType::PciCardbusBridge => {
1021                 kinfo!(
1022                     "Found pcicardbus bridge device with class code ={} subclass={} status={:#x} ",
1023                     common_header.class_code,
1024                     common_header.subclass,
1025                     common_header.status
1026                 );
1027             }
1028             HeaderType::Unrecognised(_) => {}
1029         }
1030     }
1031     kinfo!("PCI bus initialized.");
1032 }
1033 
1034 /// An identifier for a PCI bus, device and function.
1035 /// PCI设备的唯一标识
1036 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
1037 pub struct BusDeviceFunction {
1038     /// The PCI bus number, between 0 and 255.
1039     pub bus: u8,
1040     /// The device number on the bus, between 0 and 31.
1041     pub device: u8,
1042     /// The function number of the device, between 0 and 7.
1043     pub function: u8,
1044 }
1045 impl BusDeviceFunction {
1046     /// Returns whether the device and function numbers are valid, i.e. the device is between 0 and
1047     ///@brief 检测BusDeviceFunction实例是否有效
1048     ///@param self
1049     ///@return bool 是否有效
1050     #[allow(dead_code)]
1051     pub fn valid(&self) -> bool {
1052         self.device < 32 && self.function < 8
1053     }
1054 }
1055 ///实现BusDeviceFunction的Display trait,使其可以直接输出
1056 impl Display for BusDeviceFunction {
1057     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
1058         write!(f, "{:02x}:{:02x}.{}", self.bus, self.device, self.function)
1059     }
1060 }
1061 /// The location allowed for a memory BAR.
1062 /// memory BAR的三种情况
1063 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
1064 pub enum MemoryBarType {
1065     /// The BAR has a 32-bit address and can be mapped anywhere in 32-bit address space.
1066     Width32,
1067     /// The BAR must be mapped below 1MiB.
1068     Below1MiB,
1069     /// The BAR has a 64-bit address and can be mapped anywhere in 64-bit address space.
1070     Width64,
1071 }
1072 ///实现MemoryBarType与u8的类型转换
1073 impl From<MemoryBarType> for u8 {
1074     fn from(bar_type: MemoryBarType) -> Self {
1075         match bar_type {
1076             MemoryBarType::Width32 => 0,
1077             MemoryBarType::Below1MiB => 1,
1078             MemoryBarType::Width64 => 2,
1079         }
1080     }
1081 }
1082 ///实现MemoryBarType与u8的类型转换
1083 impl TryFrom<u8> for MemoryBarType {
1084     type Error = PciError;
1085     fn try_from(value: u8) -> Result<Self, Self::Error> {
1086         match value {
1087             0 => Ok(Self::Width32),
1088             1 => Ok(Self::Below1MiB),
1089             2 => Ok(Self::Width64),
1090             _ => Err(PciError::InvalidBarType),
1091         }
1092     }
1093 }
1094 
1095 /// Information about a PCI Base Address Register.
1096 /// BAR的三种类型 Memory/IO/Unused
1097 #[derive(Clone, Debug, Eq, PartialEq)]
1098 pub enum BarInfo {
1099     /// The BAR is for a memory region.
1100     Memory {
1101         /// The size of the BAR address and where it can be located.
1102         address_type: MemoryBarType,
1103         /// If true, then reading from the region doesn't have side effects. The CPU may cache reads
1104         /// and merge repeated stores.
1105         prefetchable: bool,
1106         /// The memory address, always 16-byte aligned.
1107         address: u64,
1108         /// The size of the BAR in bytes.
1109         size: u32,
1110         /// The virtaddress for a memory bar(mapped).
1111         virtaddress: u64,
1112     },
1113     /// The BAR is for an I/O region.
1114     IO {
1115         /// The I/O address, always 4-byte aligned.
1116         address: u32,
1117         /// The size of the BAR in bytes.
1118         size: u32,
1119     },
1120     Unused,
1121 }
1122 
1123 impl BarInfo {
1124     /// Returns the address and size of this BAR if it is a memory bar, or `None` if it is an IO
1125     /// BAR.
1126     ///@brief 得到某个bar的memory_address与size(前提是他的类型为Memory Bar)
1127     ///@param self
1128     ///@return Option<(u64, u32) 是Memory Bar返回内存地址与大小,不是则返回None
1129     pub fn memory_address_size(&self) -> Option<(u64, u32)> {
1130         if let Self::Memory { address, size, .. } = self {
1131             Some((*address, *size))
1132         } else {
1133             None
1134         }
1135     }
1136     ///@brief 得到某个bar的virtaddress(前提是他的类型为Memory Bar)
1137     ///@param self
1138     ///@return Option<(u64) 是Memory Bar返回映射的虚拟地址,不是则返回None
1139     pub fn virtual_address(&self) -> Option<u64> {
1140         if let Self::Memory { virtaddress, .. } = self {
1141             Some(*virtaddress)
1142         } else {
1143             None
1144         }
1145     }
1146 }
1147 ///实现BarInfo的Display trait,自定义输出
1148 impl Display for BarInfo {
1149     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1150         match self {
1151             Self::Memory {
1152                 address_type,
1153                 prefetchable,
1154                 address,
1155                 size,
1156                 virtaddress,
1157             } => write!(
1158                 f,
1159                 "Memory space at {:#010x}, size {}, type {:?}, prefetchable {},mapped at {:#x}",
1160                 address, size, address_type, prefetchable, virtaddress
1161             ),
1162             Self::IO { address, size } => {
1163                 write!(f, "I/O space at {:#010x}, size {}", address, size)
1164             }
1165             Self::Unused => {
1166                 write!(f, "Unused bar")
1167             }
1168         }
1169     }
1170 }
1171 ///一个普通PCI设备(非桥)有6个BAR寄存器,PciStandardDeviceBar存储其全部信息
1172 #[derive(Clone, Debug, Eq, PartialEq)]
1173 pub struct PciStandardDeviceBar {
1174     bar0: BarInfo,
1175     bar1: BarInfo,
1176     bar2: BarInfo,
1177     bar3: BarInfo,
1178     bar4: BarInfo,
1179     bar5: BarInfo,
1180 }
1181 
1182 impl PciStandardDeviceBar {
1183     ///@brief 得到某个bar的barinfo
1184     ///@param self ,bar_index(0-5)
1185     ///@return Result<&BarInfo, PciError> bar_index在0-5则返回对应的bar_info结构体,超出范围则返回错误
1186     pub fn get_bar(&self, bar_index: u8) -> Result<&BarInfo, PciError> {
1187         match bar_index {
1188             0 => Ok(&self.bar0),
1189             1 => Ok(&self.bar1),
1190             2 => Ok(&self.bar2),
1191             3 => Ok(&self.bar3),
1192             4 => Ok(&self.bar4),
1193             5 => Ok(&self.bar5),
1194             _ => Err(PciError::InvalidBarType),
1195         }
1196     }
1197 }
1198 ///实现PciStandardDeviceBar的Display trait,使其可以直接输出
1199 impl Display for PciStandardDeviceBar {
1200     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1201         write!(
1202             f,
1203             "\r\nBar0:{}\r\n Bar1:{}\r\n Bar2:{}\r\n Bar3:{}\r\nBar4:{}\r\nBar5:{}",
1204             self.bar0, self.bar1, self.bar2, self.bar3, self.bar4, self.bar5
1205         )
1206     }
1207 }
1208 ///实现PciStandardDeviceBar的Default trait,使其可以简单初始化
1209 impl Default for PciStandardDeviceBar {
1210     fn default() -> Self {
1211         PciStandardDeviceBar {
1212             bar0: BarInfo::Unused,
1213             bar1: BarInfo::Unused,
1214             bar2: BarInfo::Unused,
1215             bar3: BarInfo::Unused,
1216             bar4: BarInfo::Unused,
1217             bar5: BarInfo::Unused,
1218         }
1219     }
1220 }
1221 
1222 ///@brief 将某个pci设备的bar寄存器读取值后映射到虚拟地址
1223 ///@param self ,bus_device_function PCI设备的唯一标识符
1224 ///@return Result<PciStandardDeviceBar, PciError> 成功则返回对应的PciStandardDeviceBar结构体,失败则返回错误类型
1225 pub fn pci_bar_init(
1226     bus_device_function: BusDeviceFunction,
1227 ) -> Result<PciStandardDeviceBar, PciError> {
1228     let mut device_bar: PciStandardDeviceBar = PciStandardDeviceBar::default();
1229     let mut bar_index_ignore: u8 = 255;
1230     for bar_index in 0..6 {
1231         if bar_index == bar_index_ignore {
1232             continue;
1233         }
1234         let bar_info;
1235         let mut virtaddress: u64 = 0;
1236         let bar_orig = PciArch::read_config(&bus_device_function, BAR0_OFFSET + 4 * bar_index);
1237         PciArch::write_config(
1238             &bus_device_function,
1239             BAR0_OFFSET + 4 * bar_index,
1240             0xffffffff,
1241         );
1242         let size_mask = PciArch::read_config(&bus_device_function, BAR0_OFFSET + 4 * bar_index);
1243         // A wrapping add is necessary to correctly handle the case of unused BARs, which read back
1244         // as 0, and should be treated as size 0.
1245         let size = (!(size_mask & 0xfffffff0)).wrapping_add(1);
1246         //kdebug!("bar_orig:{:#x},size: {:#x}", bar_orig,size);
1247         // Restore the original value.
1248         PciArch::write_config(&bus_device_function, BAR0_OFFSET + 4 * bar_index, bar_orig);
1249         if size == 0 {
1250             continue;
1251         }
1252         if bar_orig & 0x00000001 == 0x00000001 {
1253             // I/O space
1254             let address = bar_orig & 0xfffffffc;
1255             bar_info = BarInfo::IO { address, size };
1256         } else {
1257             // Memory space
1258             let mut address = u64::from(bar_orig & 0xfffffff0);
1259             let prefetchable = bar_orig & 0x00000008 != 0;
1260             let address_type = MemoryBarType::try_from(((bar_orig & 0x00000006) >> 1) as u8)?;
1261             if address_type == MemoryBarType::Width64 {
1262                 if bar_index >= 5 {
1263                     return Err(PciError::InvalidBarType);
1264                 }
1265                 let address_top =
1266                     PciArch::read_config(&bus_device_function, BAR0_OFFSET + 4 * (bar_index + 1));
1267                 address |= u64::from(address_top) << 32;
1268                 bar_index_ignore = bar_index + 1; //下个bar跳过,因为64位的memory bar覆盖了两个bar
1269             }
1270             //kdebug!("address={:#x},size={:#x}",address,size);
1271             unsafe {
1272                 let vaddr_ptr = &mut virtaddress as *mut u64;
1273                 let mut virtsize: u64 = 0;
1274                 let virtsize_ptr = &mut virtsize as *mut u64;
1275                 let initial_mm_ptr = &mut initial_mm as *mut mm_struct;
1276                 //kdebug!("size want={:#x}", size);
1277                 if let Err(_) = MMIO_POOL.create_mmio(
1278                     size,
1279                     (VM_IO | VM_DONTCOPY) as u64,
1280                     vaddr_ptr,
1281                     virtsize_ptr,
1282                 ) {
1283                     kerror!("Create mmio failed when initing pci bar");
1284                     return Err(PciError::CreateMmioError);
1285                 };
1286                 //kdebug!("virtaddress={:#x},virtsize={:#x}",virtaddress,virtsize);
1287                 mm_map(initial_mm_ptr, virtaddress, size as u64, address);
1288             }
1289             bar_info = BarInfo::Memory {
1290                 address_type,
1291                 prefetchable,
1292                 address,
1293                 size,
1294                 virtaddress,
1295             };
1296         }
1297         match bar_index {
1298             0 => {
1299                 device_bar.bar0 = bar_info;
1300             }
1301             1 => {
1302                 device_bar.bar1 = bar_info;
1303             }
1304             2 => {
1305                 device_bar.bar2 = bar_info;
1306             }
1307             3 => {
1308                 device_bar.bar3 = bar_info;
1309             }
1310             4 => {
1311                 device_bar.bar4 = bar_info;
1312             }
1313             5 => {
1314                 device_bar.bar5 = bar_info;
1315             }
1316             _ => {}
1317         }
1318     }
1319     kdebug!("pci_device_bar:{}", device_bar);
1320     return Ok(device_bar);
1321 }
1322 
1323 /// Information about a PCI device capability.
1324 /// PCI设备的capability的信息
1325 #[derive(Debug, Copy, Clone, Eq, PartialEq)]
1326 pub struct CapabilityInfo {
1327     /// The offset of the capability in the PCI configuration space of the device function.
1328     pub offset: u8,
1329     /// The ID of the capability.
1330     pub id: u8,
1331     /// The third and fourth bytes of the capability, to save reading them again.
1332     pub private_header: u16,
1333 }
1334 
1335 /// Iterator over capabilities for a device.
1336 /// 创建迭代器以遍历PCI设备的capability
1337 #[derive(Debug)]
1338 pub struct CapabilityIterator {
1339     pub bus_device_function: BusDeviceFunction,
1340     pub next_capability_offset: Option<u8>,
1341 }
1342 
1343 impl Iterator for CapabilityIterator {
1344     type Item = CapabilityInfo;
1345     fn next(&mut self) -> Option<Self::Item> {
1346         let offset = self.next_capability_offset?;
1347 
1348         // Read the first 4 bytes of the capability.
1349         let capability_header = PciArch::read_config(&self.bus_device_function, offset);
1350         let id = capability_header as u8;
1351         let next_offset = (capability_header >> 8) as u8;
1352         let private_header = (capability_header >> 16) as u16;
1353 
1354         self.next_capability_offset = if next_offset == 0 {
1355             None
1356         } else if next_offset < 64 || next_offset & 0x3 != 0 {
1357             kwarn!("Invalid next capability offset {:#04x}", next_offset);
1358             None
1359         } else {
1360             Some(next_offset)
1361         };
1362 
1363         Some(CapabilityInfo {
1364             offset,
1365             id,
1366             private_header,
1367         })
1368     }
1369 }
1370 
1371 /// Information about a PCIe device capability.
1372 /// PCIe设备的external capability的信息
1373 #[derive(Debug, Copy, Clone, Eq, PartialEq)]
1374 pub struct ExternalCapabilityInfo {
1375     /// The offset of the capability in the PCI configuration space of the device function.
1376     pub offset: u16,
1377     /// The ID of the capability.
1378     pub id: u16,
1379     /// The third and fourth bytes of the capability, to save reading them again.
1380     pub capability_version: u8,
1381 }
1382 
1383 /// Iterator over capabilities for a device.
1384 /// 创建迭代器以遍历PCIe设备的external capability
1385 #[derive(Debug)]
1386 pub struct ExternalCapabilityIterator<'a> {
1387     pub root: &'a PciRoot,
1388     pub bus_device_function: BusDeviceFunction,
1389     pub next_capability_offset: Option<u16>,
1390 }
1391 impl<'a> Iterator for ExternalCapabilityIterator<'a> {
1392     type Item = ExternalCapabilityInfo;
1393     fn next(&mut self) -> Option<Self::Item> {
1394         let offset = self.next_capability_offset?;
1395 
1396         // Read the first 4 bytes of the capability.
1397         let capability_header = self.root.read_config(self.bus_device_function, offset);
1398         let id = capability_header as u16;
1399         let next_offset = (capability_header >> 20) as u16;
1400         let capability_version = ((capability_header >> 16) & 0xf) as u8;
1401 
1402         self.next_capability_offset = if next_offset == 0 {
1403             None
1404         } else if next_offset < 0x100 || next_offset & 0x3 != 0 {
1405             kwarn!("Invalid next capability offset {:#04x}", next_offset);
1406             None
1407         } else {
1408             Some(next_offset)
1409         };
1410 
1411         Some(ExternalCapabilityInfo {
1412             offset,
1413             id,
1414             capability_version,
1415         })
1416     }
1417 }
1418