1 // SPDX-License-Identifier: GPL-2.0 2 3 //! Rust DMA api test (based on QEMU's `pci-testdev`). 4 //! 5 //! To make this driver probe, QEMU must be run with `-device pci-testdev`. 6 7 use kernel::{ 8 bindings, 9 device::Core, 10 dma::{CoherentAllocation, Device, DmaMask}, 11 pci, 12 prelude::*, 13 types::ARef, 14 }; 15 16 struct DmaSampleDriver { 17 pdev: ARef<pci::Device>, 18 ca: CoherentAllocation<MyStruct>, 19 } 20 21 const TEST_VALUES: [(u32, u32); 5] = [ 22 (0xa, 0xb), 23 (0xc, 0xd), 24 (0xe, 0xf), 25 (0xab, 0xba), 26 (0xcd, 0xef), 27 ]; 28 29 struct MyStruct { 30 h: u32, 31 b: u32, 32 } 33 34 impl MyStruct { 35 fn new(h: u32, b: u32) -> Self { 36 Self { h, b } 37 } 38 } 39 // SAFETY: All bit patterns are acceptable values for `MyStruct`. 40 unsafe impl kernel::transmute::AsBytes for MyStruct {} 41 // SAFETY: Instances of `MyStruct` have no uninitialized portions. 42 unsafe impl kernel::transmute::FromBytes for MyStruct {} 43 44 kernel::pci_device_table!( 45 PCI_TABLE, 46 MODULE_PCI_TABLE, 47 <DmaSampleDriver as pci::Driver>::IdInfo, 48 [( 49 pci::DeviceId::from_id(bindings::PCI_VENDOR_ID_REDHAT, 0x5), 50 () 51 )] 52 ); 53 54 impl pci::Driver for DmaSampleDriver { 55 type IdInfo = (); 56 const ID_TABLE: pci::IdTable<Self::IdInfo> = &PCI_TABLE; 57 58 fn probe(pdev: &pci::Device<Core>, _info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> { 59 dev_info!(pdev.as_ref(), "Probe DMA test driver.\n"); 60 61 let mask = DmaMask::new::<64>(); 62 63 // SAFETY: There are no concurrent calls to DMA allocation and mapping primitives. 64 unsafe { pdev.dma_set_mask_and_coherent(mask)? }; 65 66 let ca: CoherentAllocation<MyStruct> = 67 CoherentAllocation::alloc_coherent(pdev.as_ref(), TEST_VALUES.len(), GFP_KERNEL)?; 68 69 || -> Result { 70 for (i, value) in TEST_VALUES.into_iter().enumerate() { 71 kernel::dma_write!(ca[i] = MyStruct::new(value.0, value.1)); 72 } 73 74 Ok(()) 75 }()?; 76 77 let drvdata = KBox::new( 78 Self { 79 pdev: pdev.into(), 80 ca, 81 }, 82 GFP_KERNEL, 83 )?; 84 85 Ok(drvdata.into()) 86 } 87 } 88 89 impl Drop for DmaSampleDriver { 90 fn drop(&mut self) { 91 dev_info!(self.pdev.as_ref(), "Unload DMA test driver.\n"); 92 93 let _ = || -> Result { 94 for (i, value) in TEST_VALUES.into_iter().enumerate() { 95 assert_eq!(kernel::dma_read!(self.ca[i].h), value.0); 96 assert_eq!(kernel::dma_read!(self.ca[i].b), value.1); 97 } 98 Ok(()) 99 }(); 100 } 101 } 102 103 kernel::module_pci_driver! { 104 type: DmaSampleDriver, 105 name: "rust_dma", 106 authors: ["Abdiel Janulgue"], 107 description: "Rust DMA test", 108 license: "GPL v2", 109 } 110