xref: /linux/drivers/gpu/nova-core/gsp.rs (revision 6dfafbd0299a60bfb5d5e277fdf100037c7ded07)
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 pub(crate) mod commands;
19 mod fw;
20 mod sequencer;
21 
22 pub(crate) use fw::{
23     GspFwWprMeta,
24     LibosParams, //
25 };
26 
27 use crate::{
28     gsp::cmdq::Cmdq,
29     gsp::fw::{
30         GspArgumentsCached,
31         LibosMemoryRegionInitArgument, //
32     },
33     num,
34 };
35 
36 pub(crate) const GSP_PAGE_SHIFT: usize = 12;
37 pub(crate) const GSP_PAGE_SIZE: usize = 1 << GSP_PAGE_SHIFT;
38 
39 /// Number of GSP pages to use in a RM log buffer.
40 const RM_LOG_BUFFER_NUM_PAGES: usize = 0x10;
41 
42 /// Array of page table entries, as understood by the GSP bootloader.
43 #[repr(C)]
44 struct PteArray<const NUM_ENTRIES: usize>([u64; NUM_ENTRIES]);
45 
46 /// SAFETY: arrays of `u64` implement `AsBytes` and we are but a wrapper around one.
47 unsafe impl<const NUM_ENTRIES: usize> AsBytes for PteArray<NUM_ENTRIES> {}
48 
49 impl<const NUM_PAGES: usize> PteArray<NUM_PAGES> {
50     /// Creates a new page table array mapping `NUM_PAGES` GSP pages starting at address `start`.
51     fn new(start: DmaAddress) -> Result<Self> {
52         let mut ptes = [0u64; NUM_PAGES];
53         for (i, pte) in ptes.iter_mut().enumerate() {
54             *pte = start
55                 .checked_add(num::usize_as_u64(i) << GSP_PAGE_SHIFT)
56                 .ok_or(EOVERFLOW)?;
57         }
58 
59         Ok(Self(ptes))
60     }
61 }
62 
63 /// The logging buffers are byte queues that contain encoded printf-like
64 /// messages from GSP-RM.  They need to be decoded by a special application
65 /// that can parse the buffers.
66 ///
67 /// The 'loginit' buffer contains logs from early GSP-RM init and
68 /// exception dumps.  The 'logrm' buffer contains the subsequent logs. Both are
69 /// written to directly by GSP-RM and can be any multiple of GSP_PAGE_SIZE.
70 ///
71 /// The physical address map for the log buffer is stored in the buffer
72 /// itself, starting with offset 1. Offset 0 contains the "put" pointer (pp).
73 /// Initially, pp is equal to 0. If the buffer has valid logging data in it,
74 /// then pp points to index into the buffer where the next logging entry will
75 /// be written. Therefore, the logging data is valid if:
76 ///   1 <= pp < sizeof(buffer)/sizeof(u64)
77 struct LogBuffer(CoherentAllocation<u8>);
78 
79 impl LogBuffer {
80     /// Creates a new `LogBuffer` mapped on `dev`.
81     fn new(dev: &device::Device<device::Bound>) -> Result<Self> {
82         const NUM_PAGES: usize = RM_LOG_BUFFER_NUM_PAGES;
83 
84         let mut obj = Self(CoherentAllocation::<u8>::alloc_coherent(
85             dev,
86             NUM_PAGES * GSP_PAGE_SIZE,
87             GFP_KERNEL | __GFP_ZERO,
88         )?);
89         let ptes = PteArray::<NUM_PAGES>::new(obj.0.dma_handle())?;
90 
91         // SAFETY: `obj` has just been created and we are its sole user.
92         unsafe {
93             // Copy the self-mapping PTE at the expected location.
94             obj.0
95                 .as_slice_mut(size_of::<u64>(), size_of_val(&ptes))?
96                 .copy_from_slice(ptes.as_bytes())
97         };
98 
99         Ok(obj)
100     }
101 }
102 
103 /// GSP runtime data.
104 #[pin_data]
105 pub(crate) struct Gsp {
106     /// Libos arguments.
107     pub(crate) libos: CoherentAllocation<LibosMemoryRegionInitArgument>,
108     /// Init log buffer.
109     loginit: LogBuffer,
110     /// Interrupts log buffer.
111     logintr: LogBuffer,
112     /// RM log buffer.
113     logrm: LogBuffer,
114     /// Command queue.
115     pub(crate) cmdq: Cmdq,
116     /// RM arguments.
117     rmargs: CoherentAllocation<GspArgumentsCached>,
118 }
119 
120 impl Gsp {
121     // Creates an in-place initializer for a `Gsp` manager for `pdev`.
122     pub(crate) fn new(pdev: &pci::Device<device::Bound>) -> Result<impl PinInit<Self, Error>> {
123         let dev = pdev.as_ref();
124         let libos = CoherentAllocation::<LibosMemoryRegionInitArgument>::alloc_coherent(
125             dev,
126             GSP_PAGE_SIZE / size_of::<LibosMemoryRegionInitArgument>(),
127             GFP_KERNEL | __GFP_ZERO,
128         )?;
129 
130         // Initialise the logging structures. The OpenRM equivalents are in:
131         // _kgspInitLibosLoggingStructures (allocates memory for buffers)
132         // kgspSetupLibosInitArgs_IMPL (creates pLibosInitArgs[] array)
133         let loginit = LogBuffer::new(dev)?;
134         dma_write!(libos[0] = LibosMemoryRegionInitArgument::new("LOGINIT", &loginit.0))?;
135 
136         let logintr = LogBuffer::new(dev)?;
137         dma_write!(libos[1] = LibosMemoryRegionInitArgument::new("LOGINTR", &logintr.0))?;
138 
139         let logrm = LogBuffer::new(dev)?;
140         dma_write!(libos[2] = LibosMemoryRegionInitArgument::new("LOGRM", &logrm.0))?;
141 
142         let cmdq = Cmdq::new(dev)?;
143 
144         let rmargs = CoherentAllocation::<GspArgumentsCached>::alloc_coherent(
145             dev,
146             1,
147             GFP_KERNEL | __GFP_ZERO,
148         )?;
149         dma_write!(rmargs[0] = fw::GspArgumentsCached::new(&cmdq))?;
150         dma_write!(libos[3] = LibosMemoryRegionInitArgument::new("RMARGS", &rmargs))?;
151 
152         Ok(try_pin_init!(Self {
153             libos,
154             loginit,
155             logintr,
156             logrm,
157             rmargs,
158             cmdq,
159         }))
160     }
161 }
162