add SimpleNic

src/main/scala/example/Configs.scala

@@ -33,6 +33,14 @@ class WithSimBlockDevice extends Config((site, here, up) => {
   }
 })
 
+class WithSimpleNIC extends Config((site, here, up) => {
+  case BuildTop => (p: Parameters) => {
+    val top = Module(LazyModule(new ExampleTopWithSimpleNIC()(p)).module)
+    top.connectNicLoopback()
+    top
+  }
+})
+
 class BaseExampleConfig extends Config(
   new WithoutTLMonitors ++
   new WithSerialAdapter ++
@@ -52,5 +60,8 @@ class SimBlockDeviceConfig extends Config(
 class BlockDeviceModelConfig extends Config(
   new WithBlockDevice ++ new WithBlockDeviceModel ++ new BaseExampleConfig)
 
+class SimpleNICConfig extends Config(
+  new WithSimpleNIC ++ new BaseExampleConfig)
+
 class WithTwoTrackers extends WithNBlockDeviceTrackers(2)
 class WithFourTrackers extends WithNBlockDeviceTrackers(4)

src/main/scala/example/Top.scala

@@ -41,3 +41,12 @@ class ExampleTopWithBlockDevice(implicit p: Parameters) extends ExampleTop
 class ExampleTopWithBlockDeviceModule(l: ExampleTopWithBlockDevice)
   extends ExampleTopModule(l)
   with HasPeripheryBlockDeviceModuleImp
+
+class ExampleTopWithSimpleNIC(implicit p: Parameters) extends ExampleTop
+    with HasPeripherySimpleNIC {
+  override lazy val module = new ExampleTopWithSimpleNICModule(this)
+}
+
+class ExampleTopWithSimpleNICModule(outer: ExampleTopWithSimpleNIC)
+  extends ExampleTopModule(outer)
+  with HasPeripherySimpleNICModuleImp

testchipip

@@ -1 +1 @@
-Subproject commit 99eb48a02b161c05bef6fdc4eb07f7040bae9390
+Subproject commit af9ce25b097abc807693905314173a80513715c4

tests/Makefile

@@ -3,7 +3,7 @@ OBJDUMP=riscv64-unknown-elf-objdump
 CFLAGS=-mcmodel=medany -std=gnu99 -O2 -fno-common -fno-builtin-printf -Wall
 LDFLAGS=-static -nostdlib -nostartfiles -lgcc
 
-PROGRAMS = pwm blkdev accum charcount
+PROGRAMS = pwm blkdev accum charcount nic-loopback
 
 default: $(addsuffix .riscv,$(PROGRAMS))
 

tests/nic-loopback.c

@@ -0,0 +1,60 @@
+#include "mmio.h"
+#include <stdlib.h>
+#include <stdio.h>
+
+#define SIMPLENIC_BASE 0x10016000L
+#define SIMPLENIC_SEND (SIMPLENIC_BASE + 0)
+#define SIMPLENIC_RECV (SIMPLENIC_BASE + 8)
+
+uint64_t src[200];
+uint64_t dst[201];
+
+void nic_send(void *data, unsigned long len)
+{
+	uintptr_t addr = ((uintptr_t) data) & ((1L << 48) - 1);
+	unsigned long packet = (len << 48) | addr;
+
+	asm volatile ("fence");
+	reg_write64(SIMPLENIC_SEND, packet);
+}
+
+void nic_recv(void *dest)
+{
+	uintptr_t addr = (uintptr_t) dest;
+	volatile uint64_t *words = (volatile uint64_t *) dest;
+
+	reg_write64(SIMPLENIC_RECV, addr);
+
+	// Poll for completion
+	while (!words[200]);
+	asm volatile ("fence");
+}
+
+#define TEST_LEN 128
+
+int main(void)
+{
+	int i;
+
+	for (i = 0; i < TEST_LEN; i++)
+		src[i] = i << 12;
+
+	printf("Sending data on loopback NIC\n");
+
+	nic_send(src, TEST_LEN * sizeof(uint64_t));
+	nic_recv(dst);
+
+	printf("Received data\n");
+
+	for (i = 0; i < TEST_LEN; i++) {
+		if (dst[i] != src[i]) {
+			printf("Data mismatch @ %d: %lx != %lx\n",
+					i, dst[i], src[i]);
+			return 1;
+		}
+	}
+
+	printf("All correct\n");
+
+	return 0;
+}