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PRCI: always use bus width >= XLen

This commit is contained in:
Wesley W. Terpstra 2016-09-15 22:06:39 -07:00
parent 2c53620275
commit e1d7f6d7df
2 changed files with 25 additions and 7 deletions

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@ -12,6 +12,8 @@ import uncore.converters._
import uncore.devices._
import uncore.util._
import rocket.Util._
import rocket.XLen
import scala.math.max
import coreplex._
/** Options for memory bus interface */
@ -282,8 +284,11 @@ trait PeripheryAON extends LazyModule with HasPeripheryParameters {
implicit val p: Parameters
val peripheryBus: TLXbar
val prci = LazyModule(new PRCI()(innerMMIOParams))
prci.node := TLFragmenter(peripheryBus.node, 4, 256)
// PRCI must be at least XLen in size for atomicity
val beatBytes = max(innerMMIOParams(XLen)/8, 4)
val prci = LazyModule(new PRCI(PRCIConfig(beatBytes))(innerMMIOParams))
// The periphery bus is 32-bit, so we may need to adapt PRCI's width
prci.node := TLFragmenter(TLWidthWidget(peripheryBus.node, 4), beatBytes, 256)
// TL1 legacy
val pDevices: ResourceManager[AddrMapEntry]

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@ -8,6 +8,7 @@ import junctions._
import junctions.NastiConstants._
import uncore.tilelink2._
import uncore.util._
import scala.math.{min,max}
import cde.{Parameters, Field}
/** Number of tiles */
@ -32,7 +33,7 @@ object PRCI {
def size = 0xc000
}
case class PRCIConfig(address: BigInt = 0x44000000, beatBytes: Int = 4)
case class PRCIConfig(beatBytes: Int, address: BigInt = 0x44000000)
trait MixPRCIParameters {
val params: (PRCIConfig, Parameters)
@ -49,7 +50,7 @@ trait PRCIModule extends Module with HasRegMap with MixPRCIParameters {
val io: PRCIBundle
val timeWidth = 64
val time = Reg(init=UInt(0, timeWidth))
val time = Reg(init=UInt(0, width = timeWidth))
when (io.rtcTick) { time := time + UInt(1) }
val timecmp = Seq.fill(p(NTiles)) { Reg(UInt(width = timeWidth)) }
@ -71,18 +72,30 @@ trait PRCIModule extends Module with HasRegMap with MixPRCIParameters {
* bffc mtime hi
*/
// laying out IPI fields suck...
// bytes=1 -> pad to 7, step 4, group 1
// bytes=2 -> pad to 15, step 2, group 1
// bytes=4 -> pad to 31, step 1, group 1
// bytes=8 -> pad to 31, step 1, group 2
// bytes=16-> pad to 31, step 1, group 4
val pad = min(c.beatBytes*8,32) - 1
val step = max(1, 4/c.beatBytes)
val group = max(1, c.beatBytes/4)
val ipi_regs = ipi.map { reg => Seq(RegField(1, reg), RegField(pad)) }.flatten.grouped(group*2).
zipWithIndex.map { case (fields, i) => (i*step -> fields) }
// Just split up time fields by bytes
val timecmp_regs = timecmp.zipWithIndex.map { case (reg, i) =>
RegField.bytes(reg, PRCI.timecmp(i)/c.beatBytes, c.beatBytes)
}.flatten
val time_reg = RegField.bytes(time, PRCI.time/c.beatBytes, c.beatBytes)
val ipi_regs = ipi.zipWithIndex.map { case (reg, i) => (i -> Seq(RegField(1, reg))) }
regmap((timecmp_regs ++ time_reg ++ ipi_regs):_*)
}
/** Power, Reset, Clock, Interrupt */
// Magic TL2 Incantation to create a TL2 Slave
class PRCI(c: PRCIConfig = PRCIConfig())(implicit val p: Parameters)
extends TLRegisterRouter(c.address, 0, 0x10000, None, c.beatBytes)(
class PRCI(c: PRCIConfig)(implicit val p: Parameters)
extends TLRegisterRouter(c.address, 0, 0x10000, None, c.beatBytes, false)(
new TLRegBundle((c, p), _) with PRCIBundle)(
new TLRegModule((c, p), _, _) with PRCIModule)