stmmac: move to softirq approach

Cargo.lock

@@ -2770,6 +2770,7 @@ dependencies = [
  "bytemuck",
  "device-api",
  "device-tree",
+ "futures-util",
  "libk",
  "libk-mm",
  "libk-util",

kernel/driver/net/stmmac/Cargo.toml

@@ -15,3 +15,4 @@ ygg_driver_net_core.path = "../core"
 tock-registers.workspace = true
 log.workspace = true
 bytemuck.workspace = true
+futures-util.workspace = true

kernel/driver/net/stmmac/src/lib.rs

@@ -10,9 +10,10 @@ use device_api::{
     interrupt::{FullIrq, InterruptHandler, IrqVector},
 };
 use device_tree::driver::{device_tree_driver, util::read_mac_address, Node, ProbeContext};
-use libk::{device::external_interrupt_controller, dma::DmaBuffer, error::Error};
+use futures_util::task::AtomicWaker;
+use libk::{device::external_interrupt_controller, dma::DmaBuffer, error::Error, task::runtime};
 use libk_mm::{address::PhysicalAddress, device::DeviceMemoryIo};
-use libk_util::{sync::IrqSafeSpinlock, OneTimeInit};
+use libk_util::{event::BitmapEvent, sync::IrqSafeSpinlock, OneTimeInit};
 use regs::{
     dma::{DMACiCR, DMACiIER, DMACiSR, DMACiTXCR, DMAC0RXCR, DMAMR, DMASBMR},
     mac::{
@@ -28,7 +29,7 @@ use ygg_driver_net_core::{
     RxPacket,
 };
 use yggdrasil_abi::net::{
-    link::{EthernetLinkState, LinkState},
+    link::{Duplex, EthernetLinkState, EthernetSpeed, LinkState},
     MacAddress,
 };
 
@@ -51,12 +52,29 @@ struct Stmmac {
     resets: Vec<ResetHandle>,
     clocks: Vec<ClockHandle>,
     irq: FullIrq,
+    softirq_events: BitmapEvent<AtomicWaker>,
 
     inner: OneTimeInit<Inner>,
     iface_id: OneTimeInit<u32>,
 }
 
+impl Inner {
+    fn link_state(&self) -> LinkState {
+        // TODO read the link state properly, i.e., read from PHY's registers, I guess? I didn't
+        //      find a nice way to read the link state from the MAC itself, it only seems to report
+        //      the MAC<->PHY link state (which is always up, obviously)
+        LinkState::Ethernet(EthernetLinkState::Up(
+            EthernetSpeed::Unknown,
+            Duplex::Unknown,
+        ))
+    }
+}
+
 impl Stmmac {
+    const SOFTIRQ_GMII_STATUS: u64 = 1 << 0;
+    const SOFTIRQ_TX_STATUS: u64 = 1 << 1;
+    const SOFTIRQ_RX_STATUS: u64 = 1 << 2;
+
     pub fn start_xmit(&self, frame: DmaBuffer<[u8]>) -> Result<(), Error> {
         let inner = self.inner.get();
         let regs = inner.regs.lock();
@@ -73,6 +91,35 @@ impl Stmmac {
 
         Ok(())
     }
+
+    async fn softirq(&self) {
+        let inner = self.inner.get();
+        let dma = self.dma.get();
+        let iface = *self.iface_id.get();
+
+        loop {
+            let events = self.softirq_events.wait().await;
+
+            if events & Self::SOFTIRQ_GMII_STATUS != 0 {
+                let link_status = inner.link_state();
+                log::info!("stmmac: link is {link_status}");
+            }
+
+            if events & Self::SOFTIRQ_TX_STATUS != 0 {
+                inner.tx_ring.lock().consume().ok();
+            }
+
+            if events & Self::SOFTIRQ_RX_STATUS != 0 {
+                let mut rx_ring = inner.rx_ring.lock();
+                rx_ring
+                    .consume(dma.as_ref(), |packet| {
+                        let packet = RxPacket::new(packet, 0, iface);
+                        ygg_driver_net_core::receive_packet(packet).ok();
+                    })
+                    .ok();
+            }
+        }
+    }
 }
 
 impl InterruptHandler for Stmmac {
@@ -83,36 +130,17 @@ impl InterruptHandler for Stmmac {
         let dma0_sr = regs.DMA.DMAC0SR.extract();
 
         if mac_isr.matches_all(MACISR::RGSMIIIS::SET) {
-            let macphycsr = regs.MAC.MACPHYCSR.extract();
+            let _ = regs.MAC.MACPHYCSR.get();
-            let state = if macphycsr.matches_all(MACPHYCSR::LNKSTS::Up) {
+            self.softirq_events.signal(Self::SOFTIRQ_GMII_STATUS);
-                "up"
-            } else {
-                "down"
-            };
-            let mode = if macphycsr.matches_all(MACPHYCSR::LNKMOD::FullDuplex) {
-                "full-duplex"
-            } else {
-                "half-duplex"
-            };
-            log::info!("RGMII link status update");
-            log::info!("Link state: link={state}, mode={mode}");
         }
 
         if dma0_sr.matches_all(DMACiSR::TI::SET) {
             regs.DMA.DMAC0SR.modify(DMACiSR::TI::SET);
-            inner.tx_ring.lock().consume().ok();
+            self.softirq_events.signal(Self::SOFTIRQ_TX_STATUS);
         }
         if dma0_sr.matches_all(DMACiSR::RI::SET) {
-            let dma = self.dma.get();
             regs.DMA.DMAC0SR.modify(DMACiSR::RI::SET);
-            let iface = *self.iface_id.get();
+            self.softirq_events.signal(Self::SOFTIRQ_RX_STATUS);
-            let mut rx_ring = inner.rx_ring.lock();
-            rx_ring
-                .consume(dma.as_ref(), |packet| {
-                    let packet = RxPacket::new(packet, 0, iface);
-                    ygg_driver_net_core::receive_packet(packet).ok();
-                })
-                .ok();
         }
 
         true
@@ -285,6 +313,9 @@ impl Device for Stmmac {
 
         intc.enable_irq(self.irq.irq)?;
 
+        let p = self.clone();
+        runtime::spawn(async move { p.softirq().await })?;
+
         Ok(())
     }
 
@@ -311,8 +342,7 @@ impl NetworkDevice for Stmmac {
     }
 
     fn link_state(&self) -> LinkState {
-        // TODO
+        self.inner.get().link_state()
-        LinkState::Ethernet(EthernetLinkState::Down)
     }
 }
 
@@ -334,6 +364,8 @@ device_tree_driver! {
                 mac,
                 irq,
 
+                softirq_events: BitmapEvent::new(AtomicWaker::new()),
+
                 dma: OneTimeInit::new(),
                 inner: OneTimeInit::new(),
                 iface_id: OneTimeInit::new(),