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, devres::Devres, pci, prelude::*}; 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(Debug)] 22 struct TestIndex(u8); 23 24 impl TestIndex { 25 const NO_EVENTFD: Self = Self(0); 26 } 27 28 struct SampleDriver { 29 pdev: pci::Device, 30 bar: Devres<Bar0>, 31 } 32 33 kernel::pci_device_table!( 34 PCI_TABLE, 35 MODULE_PCI_TABLE, 36 <SampleDriver as pci::Driver>::IdInfo, 37 [( 38 pci::DeviceId::from_id(bindings::PCI_VENDOR_ID_REDHAT, 0x5), 39 TestIndex::NO_EVENTFD 40 )] 41 ); 42 43 impl SampleDriver { 44 fn testdev(index: &TestIndex, bar: &Bar0) -> Result<u32> { 45 // Select the test. 46 bar.writeb(index.0, Regs::TEST); 47 48 let offset = u32::from_le(bar.readl(Regs::OFFSET)) as usize; 49 let data = bar.readb(Regs::DATA); 50 51 // Write `data` to `offset` to increase `count` by one. 52 // 53 // Note that we need `try_writeb`, since `offset` can't be checked at compile-time. 54 bar.try_writeb(data, offset)?; 55 56 Ok(bar.readl(Regs::COUNT)) 57 } 58 } 59 60 impl pci::Driver for SampleDriver { 61 type IdInfo = TestIndex; 62 63 const ID_TABLE: pci::IdTable<Self::IdInfo> = &PCI_TABLE; 64 65 fn probe(pdev: &mut pci::Device, info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> { 66 dev_dbg!( 67 pdev.as_ref(), 68 "Probe Rust PCI driver sample (PCI ID: 0x{:x}, 0x{:x}).\n", 69 pdev.vendor_id(), 70 pdev.device_id() 71 ); 72 73 pdev.enable_device_mem()?; 74 pdev.set_master(); 75 76 let bar = pdev.iomap_region_sized::<{ Regs::END }>(0, c_str!("rust_driver_pci"))?; 77 78 let drvdata = KBox::new( 79 Self { 80 pdev: pdev.clone(), 81 bar, 82 }, 83 GFP_KERNEL, 84 )?; 85 86 let bar = drvdata.bar.try_access().ok_or(ENXIO)?; 87 88 dev_info!( 89 pdev.as_ref(), 90 "pci-testdev data-match count: {}\n", 91 Self::testdev(info, &bar)? 92 ); 93 94 Ok(drvdata.into()) 95 } 96 } 97 98 impl Drop for SampleDriver { 99 fn drop(&mut self) { 100 dev_dbg!(self.pdev.as_ref(), "Remove Rust PCI driver sample.\n"); 101 } 102 } 103 104 kernel::module_pci_driver! { 105 type: SampleDriver, 106 name: "rust_driver_pci", 107 author: "Danilo Krummrich", 108 description: "Rust PCI driver", 109 license: "GPL v2", 110 } 111