1 // SPDX-License-Identifier: GPL-2.0 2 3 //! Rust PCI driver sample (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::{bindings, c_str, device::Core, devres::Devres, pci, prelude::*, types::ARef}; 8 9 struct Regs; 10 11 impl Regs { 12 const TEST: usize = 0x0; 13 const OFFSET: usize = 0x4; 14 const DATA: usize = 0x8; 15 const COUNT: usize = 0xC; 16 const END: usize = 0x10; 17 } 18 19 type Bar0 = pci::Bar<{ Regs::END }>; 20 21 #[derive(Copy, Clone, Debug)] 22 struct TestIndex(u8); 23 24 impl TestIndex { 25 const NO_EVENTFD: Self = Self(0); 26 } 27 28 #[pin_data(PinnedDrop)] 29 struct SampleDriver { 30 pdev: ARef<pci::Device>, 31 #[pin] 32 bar: Devres<Bar0>, 33 index: TestIndex, 34 } 35 36 kernel::pci_device_table!( 37 PCI_TABLE, 38 MODULE_PCI_TABLE, 39 <SampleDriver as pci::Driver>::IdInfo, 40 [( 41 pci::DeviceId::from_id(bindings::PCI_VENDOR_ID_REDHAT, 0x5), 42 TestIndex::NO_EVENTFD 43 )] 44 ); 45 46 impl SampleDriver { testdev(index: &TestIndex, bar: &Bar0) -> Result<u32>47 fn testdev(index: &TestIndex, bar: &Bar0) -> Result<u32> { 48 // Select the test. 49 bar.write8(index.0, Regs::TEST); 50 51 let offset = u32::from_le(bar.read32(Regs::OFFSET)) as usize; 52 let data = bar.read8(Regs::DATA); 53 54 // Write `data` to `offset` to increase `count` by one. 55 // 56 // Note that we need `try_write8`, since `offset` can't be checked at compile-time. 57 bar.try_write8(data, offset)?; 58 59 Ok(bar.read32(Regs::COUNT)) 60 } 61 } 62 63 impl pci::Driver for SampleDriver { 64 type IdInfo = TestIndex; 65 66 const ID_TABLE: pci::IdTable<Self::IdInfo> = &PCI_TABLE; 67 probe(pdev: &pci::Device<Core>, info: &Self::IdInfo) -> Result<Pin<KBox<Self>>>68 fn probe(pdev: &pci::Device<Core>, info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> { 69 dev_dbg!( 70 pdev.as_ref(), 71 "Probe Rust PCI driver sample (PCI ID: 0x{:x}, 0x{:x}).\n", 72 pdev.vendor_id(), 73 pdev.device_id() 74 ); 75 76 pdev.enable_device_mem()?; 77 pdev.set_master(); 78 79 let drvdata = KBox::pin_init( 80 try_pin_init!(Self { 81 pdev: pdev.into(), 82 bar <- pdev.iomap_region_sized::<{ Regs::END }>(0, c_str!("rust_driver_pci")), 83 index: *info, 84 }), 85 GFP_KERNEL, 86 )?; 87 88 let bar = drvdata.bar.access(pdev.as_ref())?; 89 dev_info!( 90 pdev.as_ref(), 91 "pci-testdev data-match count: {}\n", 92 Self::testdev(info, bar)? 93 ); 94 95 Ok(drvdata) 96 } 97 unbind(pdev: &pci::Device<Core>, this: Pin<&Self>)98 fn unbind(pdev: &pci::Device<Core>, this: Pin<&Self>) { 99 if let Ok(bar) = this.bar.access(pdev.as_ref()) { 100 // Reset pci-testdev by writing a new test index. 101 bar.write8(this.index.0, Regs::TEST); 102 } 103 } 104 } 105 106 #[pinned_drop] 107 impl PinnedDrop for SampleDriver { drop(self: Pin<&mut Self>)108 fn drop(self: Pin<&mut Self>) { 109 dev_dbg!(self.pdev.as_ref(), "Remove Rust PCI driver sample.\n"); 110 } 111 } 112 113 kernel::module_pci_driver! { 114 type: SampleDriver, 115 name: "rust_driver_pci", 116 authors: ["Danilo Krummrich"], 117 description: "Rust PCI driver", 118 license: "GPL v2", 119 } 120