From 8b0aabaf10316020f3a000218d9f89fd5ee8a9cf Mon Sep 17 00:00:00 2001
From: Artemis Tosini <me@artem.ist>
Date: Sat, 20 Jul 2024 01:33:49 +0000
Subject: [PATCH] Set some more registers

---
 src/buffers.rs | 17 +++++++++++++++
 src/main.rs    | 57 +++++++++++++++++++++++++++++++++++++++++++-------
 2 files changed, 67 insertions(+), 7 deletions(-)
 create mode 100644 src/buffers.rs

diff --git a/src/buffers.rs b/src/buffers.rs
new file mode 100644
index 0000000..34c1af1
--- /dev/null
+++ b/src/buffers.rs
@@ -0,0 +1,17 @@
+#[repr(transparent)]
+#[derive(Debug, Copy, Clone, Default)]
+pub struct PhysicalAddress(u64);
+
+/// Device Context Base Address Array
+/// TODO: make more page size independent
+/// Align to a page because it shouldn't cross a page and needs to be
+/// 64-byte aligned anyway
+#[repr(C, align(4096))]
+#[derive(Debug)]
+pub struct DCBAA([PhysicalAddress; 256]);
+
+impl Default for DCBAA {
+    fn default() -> Self {
+        Self([PhysicalAddress::default(); 256])
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index a3979b5..fa445e6 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,7 +1,9 @@
+mod buffers;
 mod pci;
 
 use std::sync::Arc;
 
+use buffers::DCBAA;
 use clap::Parser;
 use pci_driver::{backends::vfio::VfioPciDevice, device::PciDevice};
 
@@ -10,10 +12,6 @@ struct Args {
     /// Path of the PCIe device, e.g. /sys/bus/pci/devices/0000:02:00.0
     #[arg(short = 'd', long)]
     device: std::path::PathBuf,
-
-    /// Attempt to reset the device with sysfs
-    #[arg(short = 'r', long)]
-    reset: bool,
 }
 
 fn main() -> eyre::Result<()> {
@@ -22,16 +20,61 @@ fn main() -> eyre::Result<()> {
 
     let device = Arc::new(VfioPciDevice::open(&args.device)?);
 
-    if args.reset {
-        device.reset()?;
+    device.reset()?;
+
+    if device.iommu().alignment() != 4096 {
+        todo!("Support non-4K page size")
     }
 
-    let registers = crate::pci::load_registers(device)?;
+    let mut registers = crate::pci::load_registers(device.clone())?;
 
     log::info!(
         "xHCI version: {:04x}",
         registers.capability.hciversion.read_volatile().get()
     );
 
+    while registers
+        .operational
+        .usbsts
+        .read_volatile()
+        .controller_not_ready()
+    {
+        std::thread::sleep(std::time::Duration::from_millis(1));
+    }
+
+    let device_slots = registers
+        .capability
+        .hcsparams1
+        .read_volatile()
+        .number_of_device_slots();
+    log::debug!("Controller supports {} device slots", device_slots);
+    registers.operational.config.update_volatile(|reg| {
+        reg.set_max_device_slots_enabled(device_slots);
+    });
+
+    let dcbaa = DCBAA::default();
+
+    log::trace!(
+        "valid_iova_ranges: {:#x?}",
+        device.iommu().valid_iova_ranges()
+    );
+    log::trace!("max_num_mappings: {}", device.iommu().max_num_mappings());
+
+    let dcbaa_physaddr = 0x1000u64;
+    // TODO: Actually deal with valid iova ranges
+    unsafe {
+        device.iommu().map(
+            dcbaa_physaddr,
+            std::mem::size_of::<DCBAA>(),
+            &dcbaa as *const DCBAA as *const u8,
+            pci_driver::regions::Permissions::Read,
+        )?;
+    }
+
+    registers
+        .operational
+        .dcbaap
+        .update_volatile(|reg| reg.set(dcbaa_physaddr));
+
     Ok(())
 }