1 // SPDX-License-Identifier: GPL-2.0 2 3 use kernel::{ 4 device, 5 dma::{ 6 DataDirection, 7 DmaAddress, // 8 }, 9 kvec, 10 prelude::*, 11 scatterlist::{ 12 Owned, 13 SGTable, // 14 }, 15 }; 16 17 use crate::{ 18 dma::DmaObject, 19 firmware::riscv::RiscvFirmware, 20 gpu::{ 21 Architecture, 22 Chipset, // 23 }, 24 gsp::GSP_PAGE_SIZE, 25 num::FromSafeCast, 26 }; 27 28 /// Ad-hoc and temporary module to extract sections from ELF images. 29 /// 30 /// Some firmware images are currently packaged as ELF files, where sections names are used as keys 31 /// to specific and related bits of data. Future firmware versions are scheduled to move away from 32 /// that scheme before nova-core becomes stable, which means this module will eventually be 33 /// removed. 34 mod elf { 35 use kernel::{ 36 bindings, 37 prelude::*, 38 transmute::FromBytes, // 39 }; 40 41 /// Newtype to provide a [`FromBytes`] implementation. 42 #[repr(transparent)] 43 struct Elf64Hdr(bindings::elf64_hdr); 44 // SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability. 45 unsafe impl FromBytes for Elf64Hdr {} 46 47 #[repr(transparent)] 48 struct Elf64SHdr(bindings::elf64_shdr); 49 // SAFETY: all bit patterns are valid for this type, and it doesn't use interior mutability. 50 unsafe impl FromBytes for Elf64SHdr {} 51 52 /// Tries to extract section with name `name` from the ELF64 image `elf`, and returns it. 53 pub(super) fn elf64_section<'a, 'b>(elf: &'a [u8], name: &'b str) -> Option<&'a [u8]> { 54 let hdr = &elf 55 .get(0..size_of::<bindings::elf64_hdr>()) 56 .and_then(Elf64Hdr::from_bytes)? 57 .0; 58 59 // Get all the section headers. 60 let mut shdr = { 61 let shdr_num = usize::from(hdr.e_shnum); 62 let shdr_start = usize::try_from(hdr.e_shoff).ok()?; 63 let shdr_end = shdr_num 64 .checked_mul(size_of::<Elf64SHdr>()) 65 .and_then(|v| v.checked_add(shdr_start))?; 66 67 elf.get(shdr_start..shdr_end) 68 .map(|slice| slice.chunks_exact(size_of::<Elf64SHdr>()))? 69 }; 70 71 // Get the strings table. 72 let strhdr = shdr 73 .clone() 74 .nth(usize::from(hdr.e_shstrndx)) 75 .and_then(Elf64SHdr::from_bytes)?; 76 77 // Find the section which name matches `name` and return it. 78 shdr.find(|&sh| { 79 let Some(hdr) = Elf64SHdr::from_bytes(sh) else { 80 return false; 81 }; 82 83 let Some(name_idx) = strhdr 84 .0 85 .sh_offset 86 .checked_add(u64::from(hdr.0.sh_name)) 87 .and_then(|idx| usize::try_from(idx).ok()) 88 else { 89 return false; 90 }; 91 92 // Get the start of the name. 93 elf.get(name_idx..) 94 // Stop at the first `0`. 95 .and_then(|nstr| nstr.get(0..=nstr.iter().position(|b| *b == 0)?)) 96 // Convert into CStr. This should never fail because of the line above. 97 .and_then(|nstr| CStr::from_bytes_with_nul(nstr).ok()) 98 // Convert into str. 99 .and_then(|c_str| c_str.to_str().ok()) 100 // Check that the name matches. 101 .map(|str| str == name) 102 .unwrap_or(false) 103 }) 104 // Return the slice containing the section. 105 .and_then(|sh| { 106 let hdr = Elf64SHdr::from_bytes(sh)?; 107 let start = usize::try_from(hdr.0.sh_offset).ok()?; 108 let end = usize::try_from(hdr.0.sh_size) 109 .ok() 110 .and_then(|sh_size| start.checked_add(sh_size))?; 111 112 elf.get(start..end) 113 }) 114 } 115 } 116 117 /// GSP firmware with 3-level radix page tables for the GSP bootloader. 118 /// 119 /// The bootloader expects firmware to be mapped starting at address 0 in GSP's virtual address 120 /// space: 121 /// 122 /// ```text 123 /// Level 0: 1 page, 1 entry -> points to first level 1 page 124 /// Level 1: Multiple pages/entries -> each entry points to a level 2 page 125 /// Level 2: Multiple pages/entries -> each entry points to a firmware page 126 /// ``` 127 /// 128 /// Each page is 4KB, each entry is 8 bytes (64-bit DMA address). 129 /// Also known as "Radix3" firmware. 130 #[pin_data] 131 pub(crate) struct GspFirmware { 132 /// The GSP firmware inside a [`VVec`], device-mapped via a SG table. 133 #[pin] 134 fw: SGTable<Owned<VVec<u8>>>, 135 /// Level 2 page table whose entries contain DMA addresses of firmware pages. 136 #[pin] 137 level2: SGTable<Owned<VVec<u8>>>, 138 /// Level 1 page table whose entries contain DMA addresses of level 2 pages. 139 #[pin] 140 level1: SGTable<Owned<VVec<u8>>>, 141 /// Level 0 page table (single 4KB page) with one entry: DMA address of first level 1 page. 142 level0: DmaObject, 143 /// Size in bytes of the firmware contained in [`Self::fw`]. 144 pub(crate) size: usize, 145 /// Device-mapped GSP signatures matching the GPU's [`Chipset`]. 146 pub(crate) signatures: DmaObject, 147 /// GSP bootloader, verifies the GSP firmware before loading and running it. 148 pub(crate) bootloader: RiscvFirmware, 149 } 150 151 impl GspFirmware { 152 /// Loads the GSP firmware binaries, map them into `dev`'s address-space, and creates the page 153 /// tables expected by the GSP bootloader to load it. 154 pub(crate) fn new<'a, 'b>( 155 dev: &'a device::Device<device::Bound>, 156 chipset: Chipset, 157 ver: &'b str, 158 ) -> Result<impl PinInit<Self, Error> + 'a> { 159 let fw = super::request_firmware(dev, chipset, "gsp", ver)?; 160 161 let fw_section = elf::elf64_section(fw.data(), ".fwimage").ok_or(EINVAL)?; 162 163 let sigs_section = match chipset.arch() { 164 Architecture::Ampere => ".fwsignature_ga10x", 165 Architecture::Ada => ".fwsignature_ad10x", 166 _ => return Err(ENOTSUPP), 167 }; 168 let signatures = elf::elf64_section(fw.data(), sigs_section) 169 .ok_or(EINVAL) 170 .and_then(|data| DmaObject::from_data(dev, data))?; 171 172 let size = fw_section.len(); 173 174 // Move the firmware into a vmalloc'd vector and map it into the device address 175 // space. 176 let fw_vvec = VVec::with_capacity(fw_section.len(), GFP_KERNEL) 177 .and_then(|mut v| { 178 v.extend_from_slice(fw_section, GFP_KERNEL)?; 179 Ok(v) 180 }) 181 .map_err(|_| ENOMEM)?; 182 183 let bl = super::request_firmware(dev, chipset, "bootloader", ver)?; 184 let bootloader = RiscvFirmware::new(dev, &bl)?; 185 186 Ok(try_pin_init!(Self { 187 fw <- SGTable::new(dev, fw_vvec, DataDirection::ToDevice, GFP_KERNEL), 188 level2 <- { 189 // Allocate the level 2 page table, map the firmware onto it, and map it into the 190 // device address space. 191 VVec::<u8>::with_capacity( 192 fw.iter().count() * core::mem::size_of::<u64>(), 193 GFP_KERNEL, 194 ) 195 .map_err(|_| ENOMEM) 196 .and_then(|level2| map_into_lvl(&fw, level2)) 197 .map(|level2| SGTable::new(dev, level2, DataDirection::ToDevice, GFP_KERNEL))? 198 }, 199 level1 <- { 200 // Allocate the level 1 page table, map the level 2 page table onto it, and map it 201 // into the device address space. 202 VVec::<u8>::with_capacity( 203 level2.iter().count() * core::mem::size_of::<u64>(), 204 GFP_KERNEL, 205 ) 206 .map_err(|_| ENOMEM) 207 .and_then(|level1| map_into_lvl(&level2, level1)) 208 .map(|level1| SGTable::new(dev, level1, DataDirection::ToDevice, GFP_KERNEL))? 209 }, 210 level0: { 211 // Allocate the level 0 page table as a device-visible DMA object, and map the 212 // level 1 page table onto it. 213 214 // Level 0 page table data. 215 let mut level0_data = kvec![0u8; GSP_PAGE_SIZE]?; 216 217 // Fill level 1 page entry. 218 let level1_entry = level1.iter().next().ok_or(EINVAL)?; 219 let level1_entry_addr = level1_entry.dma_address(); 220 let dst = &mut level0_data[..size_of_val(&level1_entry_addr)]; 221 dst.copy_from_slice(&level1_entry_addr.to_le_bytes()); 222 223 // Turn the level0 page table into a [`DmaObject`]. 224 DmaObject::from_data(dev, &level0_data)? 225 }, 226 size, 227 signatures, 228 bootloader, 229 })) 230 } 231 232 /// Returns the DMA handle of the radix3 level 0 page table. 233 pub(crate) fn radix3_dma_handle(&self) -> DmaAddress { 234 self.level0.dma_handle() 235 } 236 } 237 238 /// Build a page table from a scatter-gather list. 239 /// 240 /// Takes each DMA-mapped region from `sg_table` and writes page table entries 241 /// for all 4KB pages within that region. For example, a 16KB SG entry becomes 242 /// 4 consecutive page table entries. 243 fn map_into_lvl(sg_table: &SGTable<Owned<VVec<u8>>>, mut dst: VVec<u8>) -> Result<VVec<u8>> { 244 for sg_entry in sg_table.iter() { 245 // Number of pages we need to map. 246 let num_pages = usize::from_safe_cast(sg_entry.dma_len()).div_ceil(GSP_PAGE_SIZE); 247 248 for i in 0..num_pages { 249 let entry = sg_entry.dma_address() 250 + (u64::from_safe_cast(i) * u64::from_safe_cast(GSP_PAGE_SIZE)); 251 dst.extend_from_slice(&entry.to_le_bytes(), GFP_KERNEL)?; 252 } 253 } 254 255 Ok(dst) 256 } 257