xref: /DragonOS/kernel/src/driver/firmware/efi/init.rs (revision 338f6903262c5031abad3c8e361813355a27fcdb)
1 use core::{intrinsics::unlikely, mem::size_of};
2 
3 use system_error::SystemError;
4 use uefi_raw::table::boot::{MemoryAttribute, MemoryType};
5 
6 use crate::{
7     arch::MMArch,
8     driver::{firmware::efi::EFIInitFlags, open_firmware::fdt::open_firmware_fdt_driver},
9     libs::align::{page_align_down, page_align_up},
10     mm::{
11         allocator::page_frame::PhysPageFrame, early_ioremap::EarlyIoRemap,
12         memblock::mem_block_manager, MemoryManagementArch, PhysAddr, VirtAddr,
13     },
14 };
15 
16 use super::efi_manager;
17 
18 #[allow(dead_code)]
19 #[inline(never)]
20 pub fn efi_init() {
21     kinfo!("Initializing efi...");
22     let data_from_fdt = efi_manager()
23         .get_fdt_params()
24         .expect("Failed to get fdt params");
25 
26     if data_from_fdt.systable.is_none() {
27         kerror!("Failed to get systable from fdt");
28         return;
29     }
30 
31     // kdebug!("to map memory table");
32 
33     // 映射mmap table
34     if efi_manager().memmap_init_early(&data_from_fdt).is_err() {
35         // 如果我们通过UEFI进行引导,
36         // 那么 UEFI memory map 就是我们拥有的关于内存的唯一描述,
37         // 所以如果我们无法访问它,那么继续进行下去就没有什么意义了
38 
39         kerror!("Failed to initialize early memory map");
40         loop {}
41     }
42     // kdebug!("NNNN");
43     // kwarn!("BBBB, e:{:?}", SystemError::EINVAL);
44 
45     let desc_version = efi_manager().desc_version();
46 
47     if unlikely(desc_version != 1) {
48         kwarn!("Unexpected EFI memory map version: {}", desc_version);
49     }
50 
51     let r = uefi_init(PhysAddr::new(data_from_fdt.systable.unwrap() as usize));
52     if let Err(e) = r {
53         kerror!("Failed to initialize UEFI: {:?}", e);
54         efi_manager().efi_memmap_unmap();
55         return;
56     }
57 
58     reserve_memory_regions();
59     // todo: 由于上面的`uefi_init`里面,按照UEFI的数据,初始化了内存块,
60     // 但是UEFI给的数据可能不全,这里Linux会再次从设备树检测可用内存,从而填补完全相应的内存信息
61 
62     // 并且,Linux还对EFI BootService提供的Mokvar表进行了检测以及空间保留。
63 
64     // todo: 模仿Linux的行为,做好接下来的几步工作:
65     // 参考: https://code.dragonos.org.cn/xref/linux-6.1.9/drivers/firmware/efi/efi-init.c#217
66 
67     // 保留mmap table的内存
68     let base = page_align_down(data_from_fdt.mmap_base.unwrap() as usize);
69     let offset = data_from_fdt.mmap_base.unwrap() as usize - base;
70 
71     mem_block_manager()
72         .reserve_block(
73             PhysAddr::new(base),
74             data_from_fdt.mmap_size.unwrap() as usize + offset,
75         )
76         .expect("Failed to reserve memory for EFI mmap table");
77 
78     // 保留内核的内存
79     if let Some(info) = efi_manager().inner.read().dragonstub_load_info.clone() {
80         mem_block_manager()
81             .reserve_block(
82                 PhysAddr::new(info.paddr as usize),
83                 page_align_up(info.size as usize),
84             )
85             .expect("Failed to reserve kernel itself memory");
86     }
87 
88     // todo: Initialize screen info
89 
90     kinfo!("UEFI init done!");
91 }
92 
93 #[inline(never)]
94 fn uefi_init(system_table: PhysAddr) -> Result<(), SystemError> {
95     // 定义错误处理函数
96 
97     // 错误处理:取消systable的映射
98     let err_unmap_systable = |st_vaddr: VirtAddr| {
99         EarlyIoRemap::unmap(st_vaddr)
100             .map_err(|e| {
101                 kerror!("Failed to unmap system table: {e:?}");
102             })
103             .ok();
104     };
105 
106     // 映射system table
107 
108     let st_size = size_of::<uefi_raw::table::system::SystemTable>();
109 
110     let st_vaddr = EarlyIoRemap::map_not_aligned(system_table, st_size, true).map_err(|e| {
111         kwarn!("Unable to map EFI system table, e:{e:?}");
112         e
113     })?;
114 
115     efi_manager()
116         .inner
117         .write()
118         .init_flags
119         .set(EFIInitFlags::BOOT, true);
120 
121     efi_manager()
122         .inner
123         .write()
124         .init_flags
125         .set(EFIInitFlags::EFI_64BIT, true);
126 
127     if st_vaddr.is_null() {
128         return Err(SystemError::EINVAL);
129     }
130 
131     // 解析system table
132     let st_ptr = st_vaddr.data() as *const uefi_raw::table::system::SystemTable;
133     efi_manager()
134         .check_system_table_header(unsafe { &st_ptr.as_ref().unwrap().header }, 2)
135         .map_err(|e| {
136             err_unmap_systable(st_vaddr);
137             e
138         })?;
139 
140     let st_ref = unsafe { st_ptr.as_ref().unwrap() };
141 
142     let runtime_service_paddr = efi_vaddr_2_paddr(st_ref.runtime_services as usize);
143     let mut inner_write_guard = efi_manager().inner.write();
144     inner_write_guard.runtime_paddr = Some(runtime_service_paddr);
145     inner_write_guard.runtime_service_version = Some(st_ref.header.revision);
146 
147     drop(inner_write_guard);
148     efi_manager().report_systable_header(
149         &st_ref.header,
150         efi_vaddr_2_paddr(st_ref.firmware_vendor as usize),
151     );
152 
153     {
154         // 映射configuration table
155         let table_size = st_ref.number_of_configuration_table_entries
156             * size_of::<uefi_raw::table::configuration::ConfigurationTable>();
157         let config_table_vaddr = EarlyIoRemap::map_not_aligned(
158             efi_vaddr_2_paddr(st_ref.configuration_table as usize),
159             table_size,
160             true,
161         )
162         .map_err(|e| {
163             kwarn!("Unable to map EFI configuration table, e:{e:?}");
164             err_unmap_systable(st_vaddr);
165             e
166         })?;
167         let cfg_tables = unsafe {
168             core::slice::from_raw_parts(
169                 config_table_vaddr.data()
170                     as *const uefi_raw::table::configuration::ConfigurationTable,
171                 st_ref.number_of_configuration_table_entries,
172             )
173         };
174         // 解析configuration table
175         let r = efi_manager().parse_config_tables(cfg_tables);
176 
177         EarlyIoRemap::unmap(config_table_vaddr).expect("Failed to unmap EFI config table");
178         return r;
179     }
180 }
181 
182 /// 把EFI固件提供的虚拟地址转换为物理地址。
183 ///
184 /// 因为在调用SetVirtualAddressMap()之后,`EFI SystemTable` 的一些数据成员会被虚拟重映射
185 ///
186 /// ## 锁
187 ///
188 /// 在进入该函数前,请不要持有`efi_manager().inner`的写锁
189 fn efi_vaddr_2_paddr(efi_vaddr: usize) -> PhysAddr {
190     let guard = efi_manager().inner.read();
191     let mmap = &guard.mmap;
192 
193     let efi_vaddr: u64 = efi_vaddr as u64;
194     for md in mmap.iter() {
195         if !md.att.contains(MemoryAttribute::RUNTIME) {
196             continue;
197         }
198 
199         if md.virt_start == 0 {
200             // no virtual mapping has been installed by the DragonStub
201             break;
202         }
203 
204         if md.virt_start <= efi_vaddr
205             && ((efi_vaddr - md.virt_start) < (md.page_count << (MMArch::PAGE_SHIFT as u64)))
206         {
207             return PhysAddr::new((md.phys_start + (efi_vaddr - md.virt_start)) as usize);
208         }
209     }
210 
211     return PhysAddr::new(efi_vaddr as usize);
212 }
213 
214 /// 根据UEFI提供的内存描述符的信息,填写内存区域信息
215 fn reserve_memory_regions() {
216     // 忽略之前已经发现的任何内存块。因为之前发现的内存块来自平坦设备树,
217     // 但是UEFI有自己的内存映射表,我们以UEFI提供的为准
218     mem_block_manager()
219         .remove_block(PhysAddr::new(0), PhysAddr::MAX.data())
220         .expect("Failed to remove all memblocks!");
221 
222     let inner_guard = efi_manager().inner.read_irqsave();
223     for md in inner_guard.mmap.iter() {
224         let page_count = (PhysPageFrame::new(PhysAddr::new(page_align_up(
225             (md.phys_start + (md.page_count << (MMArch::PAGE_SHIFT as u64))) as usize,
226         )))
227         .ppn()
228             - PhysPageFrame::new(PhysAddr::new(page_align_down(md.phys_start as usize))).ppn())
229             as u64;
230         let phys_start = page_align_down(md.phys_start as usize);
231         let size = (page_count << (MMArch::PAGE_SHIFT as u64)) as usize;
232 
233         // kdebug!("Reserve memory region: {:#x}-{:#x}({:#x}), is_memory: {}, is_usable_memory:{}, type: {:?}, att: {:?}", phys_start, phys_start + size, page_count, md.is_memory(), md.is_usable_memory(), md.ty, md.att);
234         if md.is_memory() {
235             open_firmware_fdt_driver().early_init_dt_add_memory(phys_start as u64, size as u64);
236             if !md.is_usable_memory() {
237                 mem_block_manager()
238                     .mark_nomap(PhysAddr::new(phys_start), size)
239                     .unwrap();
240             }
241 
242             //  keep ACPI reclaim memory intact for kexec etc.
243             if md.ty == MemoryType::ACPI_RECLAIM {
244                 mem_block_manager()
245                     .reserve_block(PhysAddr::new(phys_start), size)
246                     .unwrap();
247             }
248         }
249     }
250 }
251