xref: /linux/drivers/gpu/nova-core/driver.rs (revision 797385890759d6a011ccd7a028eed6c43142450b)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 use kernel::{
4     auxiliary,
5     device::Core,
6     devres::Devres,
7     dma::Device,
8     dma::DmaMask,
9     pci,
10     pci::{
11         Class,
12         ClassMask,
13         Vendor, //
14     },
15     prelude::*,
16     sizes::SZ_16M,
17     sync::{
18         atomic::{
19             Atomic,
20             Relaxed, //
21         },
22         Arc,
23     },
24 };
25 
26 use crate::gpu::Gpu;
27 
28 /// Counter for generating unique auxiliary device IDs.
29 static AUXILIARY_ID_COUNTER: Atomic<u32> = Atomic::new(0);
30 
31 #[pin_data]
32 pub(crate) struct NovaCore {
33     #[pin]
34     pub(crate) gpu: Gpu,
35     #[pin]
36     _reg: Devres<auxiliary::Registration>,
37 }
38 
39 const BAR0_SIZE: usize = SZ_16M;
40 
41 // For now we only support Ampere which can use up to 47-bit DMA addresses.
42 //
43 // TODO: Add an abstraction for this to support newer GPUs which may support
44 // larger DMA addresses. Limiting these GPUs to smaller address widths won't
45 // have any adverse affects, unless installed on systems which require larger
46 // DMA addresses. These systems should be quite rare.
47 const GPU_DMA_BITS: u32 = 47;
48 
49 pub(crate) type Bar0 = pci::Bar<BAR0_SIZE>;
50 
51 kernel::pci_device_table!(
52     PCI_TABLE,
53     MODULE_PCI_TABLE,
54     <NovaCore as pci::Driver>::IdInfo,
55     [
56         // Modern NVIDIA GPUs will show up as either VGA or 3D controllers.
57         (
58             pci::DeviceId::from_class_and_vendor(
59                 Class::DISPLAY_VGA,
60                 ClassMask::ClassSubclass,
61                 Vendor::NVIDIA
62             ),
63             ()
64         ),
65         (
66             pci::DeviceId::from_class_and_vendor(
67                 Class::DISPLAY_3D,
68                 ClassMask::ClassSubclass,
69                 Vendor::NVIDIA
70             ),
71             ()
72         ),
73     ]
74 );
75 
76 impl pci::Driver for NovaCore {
77     type IdInfo = ();
78     const ID_TABLE: pci::IdTable<Self::IdInfo> = &PCI_TABLE;
79 
80     fn probe(pdev: &pci::Device<Core>, _info: &Self::IdInfo) -> impl PinInit<Self, Error> {
81         pin_init::pin_init_scope(move || {
82             dev_dbg!(pdev, "Probe Nova Core GPU driver.\n");
83 
84             pdev.enable_device_mem()?;
85             pdev.set_master();
86 
87             // SAFETY: No concurrent DMA allocations or mappings can be made because
88             // the device is still being probed and therefore isn't being used by
89             // other threads of execution.
90             unsafe { pdev.dma_set_mask_and_coherent(DmaMask::new::<GPU_DMA_BITS>())? };
91 
92             let bar = Arc::pin_init(
93                 pdev.iomap_region_sized::<BAR0_SIZE>(0, c"nova-core/bar0"),
94                 GFP_KERNEL,
95             )?;
96 
97             Ok(try_pin_init!(Self {
98                 gpu <- Gpu::new(pdev, bar.clone(), bar.access(pdev.as_ref())?),
99                 _reg <- auxiliary::Registration::new(
100                     pdev.as_ref(),
101                     c"nova-drm",
102                     // TODO[XARR]: Use XArray or perhaps IDA for proper ID allocation/recycling. For
103                     // now, use a simple atomic counter that never recycles IDs.
104                     AUXILIARY_ID_COUNTER.fetch_add(1, Relaxed),
105                     crate::MODULE_NAME
106                 ),
107             }))
108         })
109     }
110 
111     fn unbind(pdev: &pci::Device<Core>, this: Pin<&Self>) {
112         this.gpu.unbind(pdev.as_ref());
113     }
114 }
115