xref: /linux/drivers/gpu/nova-core/gsp.rs (revision 4fd4acd973ec6c734e928d19aaa649d4268303a1)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 mod boot;
4 
5 use kernel::{
6     device,
7     dma::{
8         CoherentAllocation,
9         DmaAddress, //
10     },
11     dma_write,
12     pci,
13     prelude::*,
14     transmute::AsBytes, //
15 };
16 
17 pub(crate) mod cmdq;
18 mod fw;
19 
20 pub(crate) use fw::{
21     GspFwWprMeta,
22     LibosParams, //
23 };
24 
25 use crate::{
26     gsp::cmdq::Cmdq,
27     gsp::fw::{
28         GspArgumentsCached,
29         LibosMemoryRegionInitArgument, //
30     },
31     num,
32 };
33 
34 pub(crate) const GSP_PAGE_SHIFT: usize = 12;
35 pub(crate) const GSP_PAGE_SIZE: usize = 1 << GSP_PAGE_SHIFT;
36 
37 /// Number of GSP pages to use in a RM log buffer.
38 const RM_LOG_BUFFER_NUM_PAGES: usize = 0x10;
39 
40 /// Array of page table entries, as understood by the GSP bootloader.
41 #[repr(C)]
42 struct PteArray<const NUM_ENTRIES: usize>([u64; NUM_ENTRIES]);
43 
44 /// SAFETY: arrays of `u64` implement `AsBytes` and we are but a wrapper around one.
45 unsafe impl<const NUM_ENTRIES: usize> AsBytes for PteArray<NUM_ENTRIES> {}
46 
47 impl<const NUM_PAGES: usize> PteArray<NUM_PAGES> {
48     /// Creates a new page table array mapping `NUM_PAGES` GSP pages starting at address `start`.
49     fn new(start: DmaAddress) -> Result<Self> {
50         let mut ptes = [0u64; NUM_PAGES];
51         for (i, pte) in ptes.iter_mut().enumerate() {
52             *pte = start
53                 .checked_add(num::usize_as_u64(i) << GSP_PAGE_SHIFT)
54                 .ok_or(EOVERFLOW)?;
55         }
56 
57         Ok(Self(ptes))
58     }
59 }
60 
61 /// The logging buffers are byte queues that contain encoded printf-like
62 /// messages from GSP-RM.  They need to be decoded by a special application
63 /// that can parse the buffers.
64 ///
65 /// The 'loginit' buffer contains logs from early GSP-RM init and
66 /// exception dumps.  The 'logrm' buffer contains the subsequent logs. Both are
67 /// written to directly by GSP-RM and can be any multiple of GSP_PAGE_SIZE.
68 ///
69 /// The physical address map for the log buffer is stored in the buffer
70 /// itself, starting with offset 1. Offset 0 contains the "put" pointer (pp).
71 /// Initially, pp is equal to 0. If the buffer has valid logging data in it,
72 /// then pp points to index into the buffer where the next logging entry will
73 /// be written. Therefore, the logging data is valid if:
74 ///   1 <= pp < sizeof(buffer)/sizeof(u64)
75 struct LogBuffer(CoherentAllocation<u8>);
76 
77 impl LogBuffer {
78     /// Creates a new `LogBuffer` mapped on `dev`.
79     fn new(dev: &device::Device<device::Bound>) -> Result<Self> {
80         const NUM_PAGES: usize = RM_LOG_BUFFER_NUM_PAGES;
81 
82         let mut obj = Self(CoherentAllocation::<u8>::alloc_coherent(
83             dev,
84             NUM_PAGES * GSP_PAGE_SIZE,
85             GFP_KERNEL | __GFP_ZERO,
86         )?);
87         let ptes = PteArray::<NUM_PAGES>::new(obj.0.dma_handle())?;
88 
89         // SAFETY: `obj` has just been created and we are its sole user.
90         unsafe {
91             // Copy the self-mapping PTE at the expected location.
92             obj.0
93                 .as_slice_mut(size_of::<u64>(), size_of_val(&ptes))?
94                 .copy_from_slice(ptes.as_bytes())
95         };
96 
97         Ok(obj)
98     }
99 }
100 
101 /// GSP runtime data.
102 #[pin_data]
103 pub(crate) struct Gsp {
104     /// Libos arguments.
105     pub(crate) libos: CoherentAllocation<LibosMemoryRegionInitArgument>,
106     /// Init log buffer.
107     loginit: LogBuffer,
108     /// Interrupts log buffer.
109     logintr: LogBuffer,
110     /// RM log buffer.
111     logrm: LogBuffer,
112     /// Command queue.
113     pub(crate) cmdq: Cmdq,
114     /// RM arguments.
115     rmargs: CoherentAllocation<GspArgumentsCached>,
116 }
117 
118 impl Gsp {
119     // Creates an in-place initializer for a `Gsp` manager for `pdev`.
120     pub(crate) fn new(pdev: &pci::Device<device::Bound>) -> Result<impl PinInit<Self, Error>> {
121         let dev = pdev.as_ref();
122         let libos = CoherentAllocation::<LibosMemoryRegionInitArgument>::alloc_coherent(
123             dev,
124             GSP_PAGE_SIZE / size_of::<LibosMemoryRegionInitArgument>(),
125             GFP_KERNEL | __GFP_ZERO,
126         )?;
127 
128         // Initialise the logging structures. The OpenRM equivalents are in:
129         // _kgspInitLibosLoggingStructures (allocates memory for buffers)
130         // kgspSetupLibosInitArgs_IMPL (creates pLibosInitArgs[] array)
131         let loginit = LogBuffer::new(dev)?;
132         dma_write!(libos[0] = LibosMemoryRegionInitArgument::new("LOGINIT", &loginit.0))?;
133 
134         let logintr = LogBuffer::new(dev)?;
135         dma_write!(libos[1] = LibosMemoryRegionInitArgument::new("LOGINTR", &logintr.0))?;
136 
137         let logrm = LogBuffer::new(dev)?;
138         dma_write!(libos[2] = LibosMemoryRegionInitArgument::new("LOGRM", &logrm.0))?;
139 
140         let cmdq = Cmdq::new(dev)?;
141 
142         let rmargs = CoherentAllocation::<GspArgumentsCached>::alloc_coherent(
143             dev,
144             1,
145             GFP_KERNEL | __GFP_ZERO,
146         )?;
147         dma_write!(rmargs[0] = fw::GspArgumentsCached::new(&cmdq))?;
148         dma_write!(libos[3] = LibosMemoryRegionInitArgument::new("RMARGS", &rmargs))?;
149 
150         Ok(try_pin_init!(Self {
151             libos,
152             loginit,
153             logintr,
154             logrm,
155             rmargs,
156             cmdq,
157         }))
158     }
159 }
160