Changeset 1011 for branches/reconfiguration/modules/vci_mem_cache/include

Timestamp:

Aug 15, 2015, 9:02:55 PM (9 years ago)

Author:

cfuguet

Message:

reconf: introduce a scratchpad mode in the memory cache.

• Initialize the memory cache directory with all slots valid. The cache lines correspond to the lowest local memory segment (i.e. the first 256 Kbytes).

• If there is a read or write miss while in scratchpad mode, the request is dropped (black-hole behavior).

• In scratchpad mode, when a broadcast invalidate is triggered by a write, the line is not invalidated. The Read FSM needs to check in the IVT if there is a pending invalidate during a read. The same for the Cleanup FSM. This additional IVT check is only performed when in scratchpad mode.

• TODO: Support of the scratchpad mode on the CAS FSM. But probably not needed because the distributed bootloader initializes the Local, Remote and Dirty flags to 1 before enabling the MMU.

File:

• branches/reconfiguration/modules/vci_mem_cache/include/soclib/mem_cache.h (modified) (1 diff)

branches/reconfiguration/modules/vci_mem_cache/include/soclib/mem_cache.h

@@ -42 +42 @@
     MEMC_ADDR_HI,
     MEMC_BUF_LENGTH,
-    MEMC_CMD_TYPE
+    MEMC_CMD_TYPE,
+    MEMC_SCRATCHPAD
 };