Changes between Version 42 and Version 43 of InterconnexionNetworks

Timestamp:

Mar 18, 2013, 4:33:36 PM (11 years ago)

Author:

alain

Comment:

--

InterconnexionNetworks

@@ -62 +62 @@
 === 3.1  VCI encoding of the various transaction types on the direct network ===
 
-There are 8 transaction types ('''READ_DATA_UNC''', '''READ_DATA_MISS''', '''READ_INS_UNC''', '''READ_INS_MISS''', '''WRITE''', '''CAS''', '''LL''', '''SC''') on the direct network. These types are encoded through the pair of VCI fields '''CMD''' and '''PKTID'''. The '''PKTID''' field in TSAR is 4 bits long, but the MSB is ignored (reserved for future use). 
+All Hardware components connected to the direct network respect the VCI/OCP communication interface.
+
+|| VCI Field              ||  width  ||
+||                        ||         ||
+||ADDRESS                 || 40 bits ||
+||WDATA , RDATA           || 32 bits ||
+||PLEN                    || 8  bits ||
+||SRCID, RSRCID           || 14 bits ||
+||TRDID, RTRDID           || 4  bits ||
+||PKTID, RPKTID           || 4  bits || 
+||RERROR                  || 1  bit  ||         
+
+The TSAR architecture uses one single bit for the VCI RERROR field, even if the DSPIN infrastructure supports 2 bits for the error field.
+
+There are 8 transaction types on the direct network: '''READ_DATA_UNC''', '''READ_DATA_MISS''', '''READ_INS_UNC''', '''READ_INS_MISS''', '''WRITE''', '''CAS''', '''LL''', '''SC'''. These types are encoded through the VCI fields '''CMD''' and '''PKTID'''. The '''PKTID''' field in TSAR is 4 bits long, but the MSB is ignored (reserved for future use). 
 
 ||TYPE          ||CMD (2 bits)||PKTID (4 bits)|| '''PKTID''' mnemo   || '''CMD''' mnemo ||
@@ -80 +94 @@
  * bit 2 can be used to check for a TYPE_READ (bit 2 = 0)
 
-When a given initiator can send several simultaneous transactions of a given type (such as several simultaneous '''WRITE''' transactions), the VCI '''TRDID''' field is used to discriminate them. The '''TRDID''' field is 4 bits.
+When a given initiator can send several simultaneous transactions of a given type (such as several simultaneous '''WRITE''' transactions), the VCI '''TRDID''' field is used to discriminate them. The '''TRDID''' field is 4 bits, supporting up to 16 simultaneous transactions for a given initiator.
 
 ==== 3.1.1 VCI READ transaction ====
@@ -131 +145 @@
 A VCI '''CAS (Compare & Swap)''' command packet contains 2 flits.
 ('''N.B.''': this request is only sent by a L1 cache and can only target a memory cache)
- * The VCI '''CMD''' field must be set to CMD_NOP.
+ * The VCI '''CMD''' field must be set to CMD_STORE_COND.
  * The VCI '''TRDID''' field is not used by the L1 cache.
  * The VCI '''PKTID''' field must be TYPE_CAS.
@@ -155 +169 @@
 || (5)  || (5)  || (5)  || (5)  ||   (18)    ||(2)||
 
-=== 3.3 VCI parameters ===
-
-All Hardware components connected to the direct network or to the coherence network  respect the VCI/OCP communication interface.
-
-The direct network, and the coherence network being ''time-multiplexed'' on the DSPIN infrastructure, have identical VCI formats :
-
-|| VCI Field              ||  width  ||
-||                        ||         ||
-||ADDRESS                 || 40 bits ||
-||WDATA , RDATA           || 32 bits ||
-||PLEN                    || 8  bits ||
-||SRCID, RSRCID           || 14 bits ||
-||TRDID, RTRDID           || 4  bits ||
-||PKTID, RPKTID           || 4  bits || 
-||RERROR                  || 1  bit  ||         
-
-The TSAR architecture uses one single bit for the VCI RERROR field, even if the DSPIN infrastructure supports 2 bits for the error field.
-
-
-=== 3.3  DSPIN Packet format ===
-
-The VCI command & response packets are translated (actually serialized) to a more convenient DSPIN network format by the VCI/RING wrappers (in platform using the RING local interconnect) or by the VCI/DSPIN wrappers (in platforms using the XBAR local interconnect). These wrappers are located between the VCI initiator and target components and the DSPIN network. The DSPIN command packet width is 40 bits, and the DSPIN response packet width is 33 bits. The DSPIN interconnexion network uses only the following information to route both the DSPIN packets to the proper destination:
+
+=== 3.2  DSPIN encoding of the various transaction types on the direct network ===
+
+The VCI command & response packets are translated (actually serialized) to a more convenient DSPIN network format by the VCI/RING wrappers (in platform using the RING local interconnect) or by the VCI/DSPIN wrappers (in platforms using a XBAR local interconnect). These wrappers are located between the VCI initiator and target components and the DSPIN network. The DSPIN command packet width is 40 bits, and the DSPIN response packet width is 33 bits. The DSPIN interconnexion network uses only the following information to route both the DSPIN packets to the proper destination:
  * The MSB bit is the EOP flag, defining the last flit of a DSPIN packet.
  * The LSB bit of the first flit is the BC flag,  defining a DSPIN broadcast packet.