xref: /linux/drivers/gpu/nova-core/gsp.rs (revision 75f6b1de8133ea337b72901464989dc811d3305d)
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::LibosMemoryRegionInitArgument,
28     num, //
29 };
30 
31 pub(crate) const GSP_PAGE_SHIFT: usize = 12;
32 pub(crate) const GSP_PAGE_SIZE: usize = 1 << GSP_PAGE_SHIFT;
33 
34 /// Number of GSP pages to use in a RM log buffer.
35 const RM_LOG_BUFFER_NUM_PAGES: usize = 0x10;
36 
37 /// Array of page table entries, as understood by the GSP bootloader.
38 #[repr(C)]
39 struct PteArray<const NUM_ENTRIES: usize>([u64; NUM_ENTRIES]);
40 
41 /// SAFETY: arrays of `u64` implement `AsBytes` and we are but a wrapper around one.
42 unsafe impl<const NUM_ENTRIES: usize> AsBytes for PteArray<NUM_ENTRIES> {}
43 
44 impl<const NUM_PAGES: usize> PteArray<NUM_PAGES> {
45     /// Creates a new page table array mapping `NUM_PAGES` GSP pages starting at address `start`.
46     fn new(start: DmaAddress) -> Result<Self> {
47         let mut ptes = [0u64; NUM_PAGES];
48         for (i, pte) in ptes.iter_mut().enumerate() {
49             *pte = start
50                 .checked_add(num::usize_as_u64(i) << GSP_PAGE_SHIFT)
51                 .ok_or(EOVERFLOW)?;
52         }
53 
54         Ok(Self(ptes))
55     }
56 }
57 
58 /// The logging buffers are byte queues that contain encoded printf-like
59 /// messages from GSP-RM.  They need to be decoded by a special application
60 /// that can parse the buffers.
61 ///
62 /// The 'loginit' buffer contains logs from early GSP-RM init and
63 /// exception dumps.  The 'logrm' buffer contains the subsequent logs. Both are
64 /// written to directly by GSP-RM and can be any multiple of GSP_PAGE_SIZE.
65 ///
66 /// The physical address map for the log buffer is stored in the buffer
67 /// itself, starting with offset 1. Offset 0 contains the "put" pointer (pp).
68 /// Initially, pp is equal to 0. If the buffer has valid logging data in it,
69 /// then pp points to index into the buffer where the next logging entry will
70 /// be written. Therefore, the logging data is valid if:
71 ///   1 <= pp < sizeof(buffer)/sizeof(u64)
72 struct LogBuffer(CoherentAllocation<u8>);
73 
74 impl LogBuffer {
75     /// Creates a new `LogBuffer` mapped on `dev`.
76     fn new(dev: &device::Device<device::Bound>) -> Result<Self> {
77         const NUM_PAGES: usize = RM_LOG_BUFFER_NUM_PAGES;
78 
79         let mut obj = Self(CoherentAllocation::<u8>::alloc_coherent(
80             dev,
81             NUM_PAGES * GSP_PAGE_SIZE,
82             GFP_KERNEL | __GFP_ZERO,
83         )?);
84         let ptes = PteArray::<NUM_PAGES>::new(obj.0.dma_handle())?;
85 
86         // SAFETY: `obj` has just been created and we are its sole user.
87         unsafe {
88             // Copy the self-mapping PTE at the expected location.
89             obj.0
90                 .as_slice_mut(size_of::<u64>(), size_of_val(&ptes))?
91                 .copy_from_slice(ptes.as_bytes())
92         };
93 
94         Ok(obj)
95     }
96 }
97 
98 /// GSP runtime data.
99 #[pin_data]
100 pub(crate) struct Gsp {
101     /// Libos arguments.
102     pub(crate) libos: CoherentAllocation<LibosMemoryRegionInitArgument>,
103     /// Init log buffer.
104     loginit: LogBuffer,
105     /// Interrupts log buffer.
106     logintr: LogBuffer,
107     /// RM log buffer.
108     logrm: LogBuffer,
109     /// Command queue.
110     pub(crate) cmdq: Cmdq,
111 }
112 
113 impl Gsp {
114     // Creates an in-place initializer for a `Gsp` manager for `pdev`.
115     pub(crate) fn new(pdev: &pci::Device<device::Bound>) -> Result<impl PinInit<Self, Error>> {
116         let dev = pdev.as_ref();
117         let libos = CoherentAllocation::<LibosMemoryRegionInitArgument>::alloc_coherent(
118             dev,
119             GSP_PAGE_SIZE / size_of::<LibosMemoryRegionInitArgument>(),
120             GFP_KERNEL | __GFP_ZERO,
121         )?;
122 
123         // Initialise the logging structures. The OpenRM equivalents are in:
124         // _kgspInitLibosLoggingStructures (allocates memory for buffers)
125         // kgspSetupLibosInitArgs_IMPL (creates pLibosInitArgs[] array)
126         let loginit = LogBuffer::new(dev)?;
127         dma_write!(libos[0] = LibosMemoryRegionInitArgument::new("LOGINIT", &loginit.0))?;
128 
129         let logintr = LogBuffer::new(dev)?;
130         dma_write!(libos[1] = LibosMemoryRegionInitArgument::new("LOGINTR", &logintr.0))?;
131 
132         let logrm = LogBuffer::new(dev)?;
133         dma_write!(libos[2] = LibosMemoryRegionInitArgument::new("LOGRM", &logrm.0))?;
134 
135         let cmdq = Cmdq::new(dev)?;
136 
137         Ok(try_pin_init!(Self {
138             libos,
139             loginit,
140             logintr,
141             logrm,
142             cmdq,
143         }))
144     }
145 }
146