tweak settings on fu540

Also add a file, src/device/sifive/device_fu540.go, which
covers bits not in the fu540.svd.

With these changes, my simple GoSBI is running, though not correctly.

Signed-off-by: Ronald G Minnich <[email protected]>

src/device/sifive/device_fu540.go

@@ -4,6 +4,20 @@
 // as they were in the fe310.
 package sifive
 
+import (
+ "runtime/volatile"
+ "unsafe"
+)
+
+// Coreplex Local Interrupts
+type CLINT_Type struct {
+ MSIP [5]volatile.Register32 // 0x0
+ _ [0x4000 - 5*32]byte
+ MTIMECMP [5]volatile.Register64 // 0x4000
+ _ [0xbff8 - (5*64 - 0x4000 - 5*32)]byte
+ MTIME volatile.Register64 // 0xBFF8
+}
+
 var (
  // Coreplex Local Interrupts
  CLINT = (*CLINT_Type)(unsafe.Pointer(uintptr(0x2000000)))

src/machine/machine_fu540.go

@@ -3,13 +3,67 @@
 package machine
 
 import (
- "device/sifive"
  "errors"
+ "unsafe"
+
+ "device/riscv"
+ "device/sifive"
  "runtime/interrupt"
 )
 
 const deviceName = sifive.Device
 
+// non-SVD-stuff.
+// On the FE310, these are in the SVD. But not on the other
+// parts, which is ... strange.
+
+const (
+ MaxCore = 5
+ CLINTMSIP uintptr = 0x2000000
+ CLINTTimeCmp uintptr = 0x204000
+ CLINTTime uintptr = 0x20bff8
+)
+
+var (
+// Coreplex Local Interrupts
+)
+
+// MSIPn returns the n'th MSIP.
+// It is allowed to be called with a bad value, and will return
+// 0, always.
+func MSIPn(n uintptr) uint32 {
+ if n > MaxCore {
+ return 0
+ }
+ return *(*uint32)(unsafe.Pointer(CLINTMSIP + n*4))
+}
+
+// MSIP returns the MSIP for the current HART.
+func MSIP() uint32 {
+ return MSIPn(riscv.MHARTID.Get())
+}
+
+// MTimeCmpN returns the n'th MTimeCmp.
+// It is allowed to be called with a bad value, and will return
+// 0, always.
+func MTimeCmpN(n uintptr) uint64 {
+ if n > MaxCore {
+ return 0
+ }
+ return *(*uint64)(unsafe.Pointer(CLINTTimeCmp + n*8))
+}
+
+// MTimeCmp returns the MTimeCmp for the current HART.
+func MTimeCmp() uint64 {
+ return MTimeCmpN(riscv.MHARTID.Get())
+}
+
+// MTimer returns the Mtime
+func MTime() uint64 {
+ return *(*uint64)(unsafe.Pointer(CLINTTime))
+}
+
+// End non-SVD-stuff.
 func CPUFrequency() uint32 {
  return 390000000
 }

src/runtime/runtime_fu540.go

@@ -7,7 +7,7 @@ package runtime
 
 import (
  "device/riscv"
- _ "device/sifive"
+ "device/sifive"
  "machine"
  "runtime/volatile"
  "unsafe"
@@ -135,23 +135,13 @@ func buffered() int {
 var timerWakeup volatile.Register8
 
 func ticks() timeUnit {
- panic("ticks")
- // highBits := uint32(sifive.CLINT.MTIME.Get() >> 32)
- // for {
- // lowBits := uint32(sifive.CLINT.MTIME.Get() & 0xffffffff)
- // newHighBits := uint32(sifive.CLINT.MTIME.Get() >> 32)
- // if newHighBits == highBits {
- // return timeUnit(lowBits) | (timeUnit(highBits) << 32)
- // }
- // highBits = newHighBits
- // }
+ return timeUnit(sifive.CLINT.MTIME.Get())
 }
 
 func sleepTicks(d timeUnit) {
-
- panic("no sleep yet")
- //target := uint64(ticks() + d)
- //sifive.CLINT.MTIMECMP[0].Set(target)
+ hartID := riscv.MHARTID.Get()
+ target := uint64(ticks() + d)
+ sifive.CLINT.MTIMECMP[hartID].Set(target >> 32)
  riscv.MIE.SetBits(1 << 7) // MTIE
  for {
  if timerWakeup.Get() != 0 {

targets/unleashed.ld

@@ -1,7 +1,7 @@
 
 MEMORY
 {
- RAM (xrw) : ORIGIN = 0x80000000, LENGTH = 6M
+ RAM (xrw) : ORIGIN = 0x82000000, LENGTH = 6M
 }
 
 _stack_size = 2K;